EPA-453/R-95-017

1995 Protocol for Equipment Leak

Emission Estimates

Emission Standards Division

U.S. ENVIRONMENTAL PROTECTION AGENCY

Office of Air and Radiation

Office of Air Quality Planning and Standards

Research Triangle Park, North Carolina 27711

November 1995
This report has been reviewed by the Emission Standards

Division of the Office of Air Quality Planning and Standards, the

EPA and approved for publication. Mention of trade names or

commercial products is not intended to constitute endorsement or

recommendation for use. Copies of this report are available

through the Library Services Office (MD-35), U.S. Environmental

Protection Agency, Research Triangle Park, North Carolina 27711;

from the Office of Air Quality Planning and Standards Technology

Transfer Network, U.S. Environmental Protection Agency, Research

Triangle Park, North Carolina 27711; or, for a fee, from the

National Technical Information Services, 5285 Port Royal Road,

Springfield, Virginia 22161.

Publication No. EPA-453/R-95-017
FOREWORD

The EPA’s protocol for estimating equipment leak emissions

is the result of detailed information gathering and data

analysis. The protocol was written to provide a thorough

understanding of acceptable approaches to generating process

unit-specific emission estimates. In preparing this document,

the EPA has encouraged knowledgeable individuals in industry and

the regulatory community to provide comments.

The EPA has put forth considerable effort to make this

document as comprehensive as possible. However, it should be

understood that not all details and topics pertaining to

equipment leaks could feasibly be included in this document.

Additionally, it should be understood that the procedures

presented in this document are not necessarily suitable for all

applications. There will be cases where it will be necessary for

the user of the document to make a professional judgement as to

the appropriate technical approach for collecting and analyzing

data used to estimate equipment leak emissions.

Additional data on equipment leak emissions continues to be

collected. It is the intent of the EPA to periodically update

this document after analysis of the data warrants such an

update. For example, data recently collected in the petroleum

industry has been used to revise the existing refinery

correlations, which are based on data collected in the

late 1970s. Furthermore, as new techniques for collecting and

analyzing data are developed, they will be included in updated

versions of this document.

Mention of any manufacturer or company name within this

document does not represent endorsement by the EPA.

i
TABLE OF CONTENTS

Section Page

FOREWORD .......................... i

1.0 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . 1-1

2.0 DEVELOPMENT OF EQUIPMENT LEAK EMISSION ESTIMATES . . . . 2-1

2.1 Introduction . . . . . . . . . . . . . . . . . . . 2-1

2.2 General Information on the Approaches for

Estimating Equipment Leak Emissions . . . . . . . . 2-3

2.2.1 Equipment Leak Emission Estimation

Approaches . . . . . . . . . . . . . . . . . 2-3

2.2.2 Overview of Equipment Leak Data Collection . 2-6

2.3 Approaches for Estimating Equipment Leak

Emissions.................... 2-10

2.3.1 Average Emission Factor Approach..... 2-10

2.3.2 Screening Ranges Approach ........ 2-18

2.3.3 EPA Correlation Approach......... 2-24

2.3.4 Unit-Specific Correlation Approach.... 2-38

2.4 Special Topics ................. 2-44

2.4.1 Speciating Emissions........... 2-45

2.4.2 Using Response Factors.......... 2-46

2.4.3 Monitoring Instrument Type and Calibration

Gas . . . . . . . . . . . . . . . . . . . 2-51

2.4.4 Estimating Emissions for Equipment Not

Screened................. 2-51

2.4.5 Using Screening Data Collected at Several

Different Times ............. 2-52

2.4.6 Estimating VOC Emission Rates from Equipment

Containing Non-VOC’s........... 2-52

2.4.7 Estimating Equipment Leak Emissions of

Inorganic Compounds ........... 2-53

2.5 References ................... 2-54

3.0 SOURCE SCREENING . . . . . . . . . . . . . . . . . . . . 3-1

3.1 Introduction . . . . . . . . . . . . . . . . . . . 3-1

3.2 Monitoring Instruments . . . . . . . . . . . . . . 3-2

3.2.1 Operating Principles and Limitations of

Portable VOC Detection Devices . . . . . . . 3-2

ii
TABLE OF CONTENTS (Continued)

Section Page

3.2.2 Specifications and Performance Criteria of

Portable VOC Detection Devices . . . . . . . 3-4

3.2.3 Use of Monitoring Devices That Do Not Meet

EPA Reference Method 21 Requirements... 3-10

3.3 The Screening Program.............. 3-12

3.3.1 Identification of Equipment to be Screened 3-12

3.3.2 Procedure for Screening ......... 3-15

3.3.3 Data Handling .............. 3-25

3.4 References ................... 3-27

4.0 MASS EMISSION SAMPLING . . . . . . . . . . . . . . . . . 4-1

4.1 Introduction . . . . . . . . . . . . . . . . . . . 4-1

4.2 Sampling Methods . . . . . . . . . . . . . . . . . 4-2

4.2.1 Vacuum Method . . . . . . . . . . . . . . . 4-4

4.2.2 Blow-Through Method . . . . . . . . . . . . 4-8

4.3 Source Enclosure ................ 4-15

4.3.1 Valves.................. 4-15

4.3.2 Pumps and Agitators ........... 4-16

4.3.3 Compressors ............... 4-17

4.3.4 Connectors................ 4-17

4.3.5 Relief Valves .............. 4-18

4.4 Analytical Techniques.............. 4-18

4.4.1 Analytical Instrumentation........ 4-19

4.4.2 Calibration of Analytical Instruments . . 4-19

4.4.3 Analytical Techniques for Condensate... 4-21

4.4.4 Calibration Procedures for the Portable

Monitoring Instrument .......... 4-21

4.5 Quality Control and Quality Assurance Guidelines 4-21

4.5.1 Quality Control Procedures........ 4-22

4.5.2 Quality Assurance Procedures....... 4-25

4.6 References ................... 4-29

5.0 ESTIMATION OF CONTROL EFFICIENCIES FOR EQUIPMENT LEAK

CONTROL TECHNIQUES . . . . . . . . . . . . . . . . . . . 5-1

5.1 Introduction . . . . . . . . . . . . . . . . . . . 5-1

iii
TABLE OF CONTENTS (Continued)

Section Page

5.2 Equipment Modification Control Efficiency . . . . . 5-1

5.2.1 Closed-Vent Systems . . . . . . . . . . . . 5-2

5.2.2 Pumps . . . . . . . . . . . . . . . . . . . 5-2

5.2.3 Compressors . . . . . . . . . . . . . . . . 5-4

5.2.4 Pressure Relief Valves . . . . . . . . . . . 5-4

5.2.5 Valves . . . . . . . . . . . . . . . . . . . 5-5

5.2.6 Connectors . . . . . . . . . . . . . . . . . 5-5

5.2.7 Open-Ended Lines . . . . . . . . . . . . . . 5-6

5.2.8 Sampling Connections . . . . . . . . . . . . 5-6

5.3 Leak Detection and Repair Control Effectiveness . . 5-6

5.3.1 Approach for Estimating LDAR Control

Effectiveness . . . . . . . . . . . . . . . 5-8

5.3.2 Example Application of Approach ..... 5-57

5.4 References ................... 5-61

APPENDICES

A Example Calculations . . . . . . . . . . . . . . . . . . A-1

B Leak Rate Screening Value Correlation Development and

Revision of SOCMI Correlations and Emission Factors . . B-1

C Revision of Petroleum Industry Correlations and Emission

Factor . . . . . . . . . . . . . . . . . . . . . . . . . C-1

D Response Factors . . . . . . . . . . . . . . . . . . . . D-1

E Selection of Sample Size for Screening Connectors . . . E-1

F Reference Method 21 . . . . . . . . . . . . . . . . . . F-1

G Development of Leak Rate Versus Fraction Leaking

Equations and Determination of LDAR Control

Effectiveness . . . . . . . . . . . . . . . . . . . . . G-1

iv
LIST OF TABLES

Table Page

2-1 SOCMI Average Emission Factors ......... 2-12

2-2 Refinery Average Emission Factors........ 2-13

2-3 Marketing Terminal Average Emission Factors... 2-14

2-4 Oil and Gas Production Operations Average Emission

Factors..................... 2-15

2-5 SOCMI Screening Ranges Emission Factors..... 2-19

2-6 Refinery Screening Ranges Emission Factors . . . 2-20

2-7 Marketing Terminal Screening Ranges Emission

Factors..................... 2-21

2-8 Oil and Gas Production Operations Screening Ranges

Emission Factors ................ 2-22

2-9 SOCMI Leak Rate/Screening Value Correlations . . 2-26

2-10 Petroleum Industry Leak Rate/Screening Value

Correlations .................. 2-27

2-11 Default-Zero Values: SOCMI Process Units.... 2-33

2-12 Default-Zero Values: Petroleum Industry .... 2-34

2-13 10,000 and 100,000 ppmv Screening Value Pegged Emission

Rates For SOCMI Process Units.......... 2-36

2-14 10,000 and 100,000 ppmv Screening Value Pegged Emission

Rates For the Petroleum Industry ........ 2-37

3-1 Performance Criteria for Portable VOC Detectors . . 3-6

3-2 Portable VOC Detection Instruments ....... 3-11

3-3 Equipment Leak Emission Sources......... 3-13

3-4 Example Field Sheets For Equipment Screening Data 3-26

4-1 Calculation Procedures For Leak Rate When Using

the Vacuum Method . . . . . . . . . . . . . . . . . 4-9

4-2 Calculation Procedures For Leak Rate When Using

the Blow-Through Method............. 4-13

4-3 Example GC Calibration Data Sheet........ 4-20

v
LIST OF TABLES (Continued)

Table Page

4-4 Example Data Collection Form For Fugitive

Emissions Bagging Test (Blow-Through Method) . . 4-23

4-5 Example Data Collection Form For Fugitive

Emissions Bagging Test (Vacuum Method) ..... 4-24

4-6 Example Drift Test Report Form ......... 4-28

5-1 Summary of Equipment Modifications . . . . . . . . 5-3

5-2 Control Effectiveness For an LDAR Program At a

SOCMI Process Unit . . . . . . . . . . . . . . . . 5-9

5-3 Control Effectiveness For an LDAR Program At a

Refinery Process Unit.............. 5-10

5-4 Equations Relating Average Leak Rate to Fraction

Leaking at SOCMI Units ............. 5-46

5-5 Equations Relating Average Leak Rate to Fraction

Leaking at Refinery Units............ 5-47

5-6 Equations Relating Average Leak Rate to Fraction

Leaking At Marketing Terminal Units....... 5-48

5-7 Equations Relating Average Leak Rate to Fraction

Leaking At Oil and Gas Production Operating

Units...................... 5-50

5-8 Values Used in Example Calculation ....... 5-58

5-9 Example Calculation To Determine the Final Leak

Frequency Of SOCMI Gas Valves In a Monthly

Monitoring LDAR Program With a Leak Definition

of 10,000 ppmv ................. 5-60

vi
LIST OF FIGURES

Figure Page

2-1 Overview of Data Collection and Analysis

Approaches for Developing Equipment Leak

Emissions Inventory . . . . . . . . . . . . . . . . 2-4

2-2 SOCMI Correlations Relating Total Organic Compound

(TOC) Leak Rate to Screening Value:

0 - 1,000 ppmv ................. 2-28

2-3 SOCMI Correlations Relating Total Organic Compound

(TOC) Leak Rate to Screening Value:

1,000 - 1,000,000 ppmv ............. 2-29

2-4 Petroleum Industry Correlations Relating Total Organic

Compound (TOC) Leak Rate to Screening Value:

1,000 - 1,000,000 ppmv ............. 2-30

2-5 Petroleum Industry Correlations Relating Total Organic

Compound (TOC) Leak Rate to Screening Value:

1,000 - 1,000,000 ppmv ............. 2-31

3-1 Gate Valves................... 3-17

3-2 Globe Valves .................. 3-18

3-3 Lubricated Plug Valve.............. 3-19

3-4 Ball Valve and Butterfly Valve ......... 3-20

3-5 Weir-Type Diaphragm Valve and Check Valves . . . 3-21

3-6 Centrifugal Pumps................ 3-23

3-7 Spring-Loaded Relief Valve ........... 3-24

4-1 Sampling Train for Bagging a Source Using the

Vacuum Method . . . . . . . . . . . . . . . . . . . 4-5

4-2 Equipment Required for the Blow-Through Sampling

Technique.................... 4-10

5-1 SOCMI Gas Valve Average Leak Rate Versus Fraction

Leaking at Several Leak Definitions....... 5-11

5-2 SOCMI Light Liquid Valve Average Leak Rate Versus

Fraction Leaking at Several Leak Definitions . . 5-12

5-3 SOCMI Light Liquid Pump Average Leak Rate Versus

Fraction Leaking at Several Leak Definitions . . 5-13

vii
LIST OF FIGURES (Continued)

Figure Page

5-4 SOCMI Connector Average Leak Rate Versus Fraction

Leaking at Several Leak Definitions....... 5-14

5-5 Refinery Gas Valve Average Leak Rate Versus

Fraction Leaking at Several Leak Definitions . . 5-15

5-6 Refinery Light Liquid Valve Average Leak Rate

Versus Fraction Leaking at Several Leak

Definitions................... 5-16

5-7 Refinery Light Liquid Pump Average Leak Rate

Versus Fraction Leaking at Several Leak

Definitions................... 5-17

5-8 Refinery Connector Average Leak Rate Versus

Fraction Leaking at Several Leak Definitions . . 5-18

5-9 Marketing Terminal Gas Fittings Average Leak Rate

Versus Fraction Leaking at Several Leak

Definitions................... 5-19

5-10 Marketing Terminal Light Liquid Fittings Average Leak

Rate Versus Fraction Leaking at Several Leak

Definitions................... 5-20

5-11 Marketing Terminal Gas Others Average Leak Rate Versus

Fraction Leaking at Several Leak Definitions . . 5-21

5-12 Marketing Terminal Light Liquid Others Average Leak

Rate Versus Fraction Leaking at Several Leak

Definitions................... 5-22

5-13 Marketing Terminal Light Liquid Pumps Average Leak Rate

Versus Fraction Leaking at Several Leak

Definitions................... 5-23

5-14 Marketing Terminal Gas Valves Average Leak Rate Versus

Fraction Leaking at Several Leak Definitions . . 5-24

5-15 Marketing Terminal Light Liquid Valves Average Leak

Rate Versus Fraction Leaking at Several Leak

Definitions................... 5-25

5-16 Oil and Gas Production Gas Connectors Average Leak Rate

Versus Fraction Leaking at Several Leak

Definitions................... 5-27

viii
LIST OF FIGURES (Continued)

Figure Page

5-17 Oil and Gas Production Light Oil Connectors Average

Leak Rate Versus Fraction Leaking at Several Leak

Definitions................... 5-28

5-18 Oil and Gas Production Water/Oil Connectors Average

Leak Rate Versus Fraction Leaking at Several Leak

Definitions................... 5-29

5-19 Oil and Gas Production Gas Flanges Average Leak Rate

Versus Fraction Leaking at Several Leak

Definitions................... 5-30

5-20 Oil and Gas Production Light Oil Flanges Average Leak

Rate Versus Fraction Leaking at Several Leak

Definitions................... 5-31

5-21 Oil and Gas Production Gas Open-Ended Lines Average

Leak Rate Versus Fraction Leaking at Several Leak

Definitions................... 5-32

5-22 Oil and Gas Production Heavy Oil Open-Ended Lines

Average Leak Rate Versus Fraction Leaking at Several

Leak Definitions ................ 5-33

5-23 Oil and Gas Production Light Oil Open-Ended Lines

Average Leak Rate Versus Fraction Leaking at Several

Leak Definitions ................ 5-34

5-24 Oil and Gas Production Water/Oil Open-Ended Lines

Average Leak Rate Versus Fraction Leaking at Several

Leak Definitions ................ 5-35

5-25 Oil and Gas Production Gas Other Average Leak Rate

Versus Fraction Leaking at Several Leak

Definitions................... 5-36

5-26 Oil and Gas Production Heavy Oil Other Average Leak

Rate Versus Fraction Leaking at Several Leak

Definitions................... 5-37

5-27 Oil and Gas Production Light Oil Other Average Leak

Rate Versus Fraction Leaking at Several Leak

Definitions................... 5-38

5-28 Oil and Gas Production Water/Oil Other Average Leak

Rate Versus Fraction Leaking at Several Leak

Definitions................... 5-39

ix
LIST OF FIGURES (Continued)

Figure Page

5-29 Oil and Gas Production Gas Pumps Average Leak Rate

Versus Fraction Leaking at Several Leak

Definitions................... 5-40

5-30 Oil and Gas Production Light Oil Pumps Average Leak

Rate Versus Fraction Leaking at Several Leak

Definitions................... 5-41

5-31 Oil and Gas Production Gas Valves Average Leak Rate

Versus Fraction Leaking at Several Leak

Definitions................... 5-42

5-32 Oil and Gas Production Heavy Oil Valves Average Leak

Rate Versus Fraction Leaking at Several Leak

Definitions................... 5-43

5-33 Oil and Gas Production Light Oil Valves Average Leak

Rate Versus Fraction Leaking at Several Leak

Definitions................... 5-44

5-34 Oil and Gas Production Water/Oil Valves Average Leak

Rate Versus Fraction Leaking at Several Leak

Definitions................... 5-45

5-35 Marketing Terminals Light Liquid Pumps Average Leak

Rate Versus Fraction Leaking at Several Leak

Definitions................... 5-55

x
1.0 INTRODUCTION

This document is an update to the EPA equipment leaks

protocol document ("Protocol for Equipment Leak Emission

Estimates," EPA-453/R-93-026, June 1993). The purpose of this

document is the same as the original protocol document and

subsequent revisions- to present standard procedures for

estimating mass emissions from equipment leaks. However, this

document publishes the results of additional data collection and

analysis that has occurred since the original protocol and

subsequent revisions were published, and also expands on some of

the topics that were covered in the original protocol.

Some of the new features of the updated protocol are:

(1) New correlation equations, default zero emission rates,

and pegged emission rates for the petroleum industry that

replace the refinery correlations previously published

are presented. The correlations relate screening values

obtained using a portable monitoring instrument to mass

emissions.

(2) The document has been expanded to include emission

factors for marketing terminals and for oil and gas

production operations. The refinery emission factors

were not revised due to an unavailability of new data.

(3) Pegged emission rates for pegged readings at 10,000 ppmv

have been added for SOCMI process units.

(4) Several of the equations in this version of the protocol

have been revised by simplifying the symbols to more

clearly communicate the concept being conveyed.

(5) An adjustment has been added to the blow-through method

of calculating mass emissions. This adjustment more

accurately accounts for the total flow through the bag.

1-1
As with the original protocol document, this document

presents standard procedures for general use in generating

unit-specific emission estimates for permitting and inventories.

The document describes methodologies the EPA considers

appropriate for development of equipment leak emission estimates.

These methodologies are intended to assist States and industry in

their efforts to estimate equipment leak emissions.

The updated protocol is divided into five chapters and

several appendices. Chapter 2.0 describes how to estimate

equipment leak emissions. Chapter 3.0 describes collecting

screening data that can be used in the emission estimates.

Chapter 4.0 describes collecting unit-specific equipment leak

mass emissions data. Chapter 5.0 describes how to estimate the

control efficiencies of equipment leak control techniques. The

appendices support information contained in the chapters. Each

of these chapters and the appendices are briefly described below.

Chapter 2.0 presents the four approaches for estimating total

organic emissions from equipment leaks. These approaches are:

Average Emission Factor Approach;

Screening Ranges Approach;

EPA Correlation Approach; and

Unit-Specific Correlation Approach.

Additionally, several topics that are relevant to estimating

equipment leak emissions are addressed. These topics include

speciating equipment leak emissions of individual compounds from

an equipment piece containing a mixture, using response factors,

estimating emissions of volatile organic compounds, estimating

emissions of inorganic compounds, and other topics not

specifically related to any one of the four approaches.

Chapter 3.0 explains how to perform a screening survey at a

process unit. Requirements for the use of a portable monitoring

instrument are described. These requirements are based on the

EPA Reference Method 21. Additionally, in chapter 3.0, guidance

is provided on how to set up a screening program and how to

screen different types of equipment.

1-2
Chapter 4.0, explains how to collect equipment leak rate data

(bagging data) by enclosing individual equipment in a "bag" and

measuring mass emissions. These data can be used to develop

unit-specific leak rate/screening value correlations.

Chapter 4.0 details the rigorous steps that need to be followed

when collecting the bagging data to generate unit-specific

correlations. These steps are intended to ensure that the data

are of high quality.

Chapter 5.0, explains how to estimate the control efficiency

of equipment leak emission control techniques. The two primary

control techniques for reducing equipment leak emissions are

(1) equipment modifications (such as replacing a standard valve

with a sealless type) and (2) implementing a leak detection and

repair (LDAR) program. Control efficiencies for different

equipment leak modifications are summarized, and an approach for

estimating the control efficiency of any LDAR program is

provided.

Appendices A through G provide additional information

supporting the material in the chapters. Appendix A contains

detailed example calculations using the approaches described in

chapter 2.0. Appendix B documents how the SOCMI correlations and

emission factors were revised. Appendix B also serves as a

demonstration of how data can be analyzed to develop

unit-specific correlations. Appendix C presents the rationale

for the development of the petroleum industry correlations, as

well as the background for the development of marketing terminal

and oil and gas production operations emission factors.

Appendix D summarizes available data on response factors.

Appendix E provides guidance on how to collect representative

screening data for connectors. Appendix F contains a copy of the

EPA Reference Method 21. Finally, appendix G demonstrates how

LDAR control efficiencies presented in chapter 5.0 were

calculated.

1-3
2.0. DEVELOPMENT OF EQUIPMENT LEAK EMISSION ESTIMATES

2.1 INTRODUCTION

The purpose of this chapter is to describe the methods for

estimating mass emissions from equipment leaks in a chemical

processing unit. Four approaches for estimating equipment leak

emissions are presented:

Approach 1: Average Emission Factor Approach;

Approach 2: Screening Ranges Approach;

Approach 3: EPA Correlation Approach; and

Approach 4: Unit-Specific Correlation Approach.

General information on these approaches is presented in

section 2.2, and detailed information on applying each of the

approaches is presented in section 2.3. Included in section 2.3

are emission factors and leak rate/screening value correlations

for use in estimating emissions from equipment leaks in the

petroleum industry and the synthetic organic chemical

manufacturing industry (SOCMI). The SOCMI emission factors and

correlations were revised and introduced in the 1993 update of

this document. The refinery correlations that have been revised

and expanded to include the entire petroleum industry are

introduced in this document. Additionally, emission factors for

marketing terminals are introduced in this document. Emission

factors for gas plants that have been updated and expanded to

included oil and gas production operations are also introduced in

this document. The procedures in this document estimate

emissions of total organic compounds (TOC’s). However, special

procedures are also described for the purpose of estimating

volatile organic compounds (VOC’s). As defined by the EPA, VOC’s

2-1
include all organic compounds except those specifically excluded

by the EPA due to negligible photochemical activity.

After the four approaches have been discussed, topics that

are not specifically related to any particular approach, but are

relevant to how equipment leak emissions are estimated, are

addressed in section 2.4. These topics include:

Estimating emissions of individual compounds within a

mixture;

Using response factors when estimating emissions;

Considerations regarding the monitoring instrument used;

Estimating emissions of equipment not screened when other

equipment have been screened;

Using screening data collected at different times;

Estimating VOC emissions from equipment containing

organic compounds excluded from the EPA’s classification

of TOC’s; and

Estimating emissions from equipment containing inorganic

compounds.

Appendices A through E contain supporting documentation for

the material presented in this chapter. Appendix A contains

detailed example calculations that demonstrate the four

approaches for estimating equipment leak emissions, as well as

the topics discussed in section 2.4. Appendix B presents details

on how unit-specific correlations can be developed, and also

presents background information on the revision of the SOCMI

correlations and emission factors. Appendix C presents

background information on the development of average emission

factors and correlation equations for the petroleum industry.

Appendix D offers a detailed listing of available response

factors. Appendix E contains information on the minimum number

of connectors in a process unit that must be screened in order to

obtain a representative sample.

2-2
2.2 GENERAL INFORMATION ON THE APPROACHES FOR ESTIMATING

EQUIPMENT LEAK EMISSIONS

This section presents general information on the four

approaches for estimating equipment leak emissions. Each

approach is briefly described, and data requirements for each are

summarized. Additionally, background information is presented to

provide an historical overview of data collection and analysis on

emissions of VOC’s from equipment leaks.

2.2.1 Equipment Leak Emission Estimation Approaches

The four approaches described here can be used by any

chemical-handling facility to develop an inventory of TOC or VOC

emissions from equipment leaks. The approaches, in order of

increasing refinement, are: Average Emission Factor Approach,

Screening Ranges Approach, EPA Correlation Approach, and

Unit-Specific Correlation Approach.

In general, the more refined approaches require more data and

provide more accurate emission estimates for a process unit. In

the Average Emission Factor Approach and the Screening Ranges

Approach, emission factors are combined with equipment counts to

estimate emissions. To estimate emissions with the EPA

Correlation Approach, measured concentrations (screening values)

for all equipment are individually entered into general

correlations developed by the EPA. In the Unit-Specific

Correlation Approach, screening and leak rate data are measured

for a select set of individual equipment components and then used

to develop unit-specific correlations. Screening values for all

components are then entered into these unit-specific correlations

to estimate emissions.

Figure 2-1 is an overview of the data collection and analysis

required to apply each of the approaches. As can be seen from

this figure, all of the approaches require an accurate count of

equipment components by type of equipment (i.e., valves, pumps,

connectors, etc.). Additionally, for some of the equipment

types, the count must be further described by service (i.e.,

heavy liquid, light liquid, and gas).

2-3
2-4

Figure 2-1. Overview of Data Collection and Analysis

Approaches for Developing Equipment Leak

Emissions Inventory
Except for the Average Emission Factor Approach, all of the

approaches require screening data. Screening data are collected

by using a portable monitoring instrument to sample air from

potential leak interfaces on individual pieces of equipment. A

screening value is a measure of the concentration of leaking

compounds in the ambient air that provides an indication of the

leak rate from an equipment piece, and is measured in units of

parts per million by volume (ppmv). The procedures for

collecting screening data are presented in chapter 3.0.

In addition to equipment counts and screening data, the

Unit-Specific Correlation Approach requires bagging data.

Bagging data consist of screening values and their associated

measured leak rates. A leak rate is measured by enclosing an

equipment piece in a bag to determine the actual mass emission

rate of the leak. The screening values and measured leak rates

from several pieces of equipment are used to develop a

unit-specific correlation. The resulting leak rate/screening

value correlation predicts the mass emission rate as a function

of the screening value. Procedures for collecting bagging data

are described in detail in chapter 4.0.

Each of the approaches are applicable to any

chemical-handling facility. However, the EPA has developed more

than one set of emission factors and correlations, and the type

of process unit being considered governs which set must be used

to estimate emissions. Historical data collection on emissions

from equipment leaks in SOCMI, refineries, marketing terminals

and oils and gas production operations have yielded emission

factors and correlations for these source categories. Emission

factors and correlations for other source categories have not

been developed.

For process units in source categories for which emission

factors and/or correlations have not been developed, the factors

and/or correlations already developed can be utilized. However,

appropriate evidence should indicate that the existing emission

factors and correlations are applicable to the source category in

question. Criteria for determining the appropriateness of

2-5
applying existing emission factors and correlations to another

source category may include one or more of the following:

(1) process design, (2) process operation parameters

(i.e., pressure and temperature), (3) types of equipment used,

and (4) types of material handled. For example, in most cases,

SOCMI emission factors and correlations are applicable for

estimating equipment leak emissions from the polymer and resin

manufacturing industry. This is because, in general, these two

industries have comparable process design and comparable process

operation, they use the same types of equipment, and they tend to

use similar feedstock.

2.2.2 Overview of Equipment Leak Data Collection

Data on equipment leak emissions of organic compounds have

been collected from refineries, marketing terminals, oil and gas

production operations, and SOCMI process units. Emission factors

and correlations have been developed for the following equipment

types: valves, pumps, compressors, pressure relief valves,

connectors, flanges, and open-ended lines. An "others" category

has also been developed for the petroleum industry. For sampling

connections, an average emission factor has been developed that

estimates the typical amount of material purged when a sample is

collected. A brief history of the development of these factors

and correlations is presented below.

2.2.2.1 Refinery Assessment Study.1,2 In the late 1970s,

the EPA initiated the Petroleum Refinery Assessment Study, and

equipment leak data from 13 refineries were collected. In this

study, equipment was screened and the majority of sources that

had screening values over 200 ppmv were bagged. Bagged equipment

emission rates were reported as non-methane organic compound

emission rates. Average emission factors and correlations for

each equipment type were developed based on the screening and

bagging data collected in this study.

The Refinery Assessment Study included an investigation of

possible correlations between equipment leaks and process

variables. The only process variables found to correlate with

mass emission rates in a statistically significant manner were

2-6
(1) the phase of the process stream (service), and (2) the

relative volatility of liquid streams. This finding led to the

separation of data for valves, pumps, and pressure relief valves

by type of service. Three service categories were defined:

Gas/vapor - material in a gaseous state at operating

conditions;

Light liquid - material in a liquid state in which the

sum of the concentration of individual constituents with

a vapor pressure over 0.3 kilopascals (kPa) at 20 oC is

greater than or equal to 20 weight percent; and

Heavy liquid - not in gas/vapor service or light liquid

service.

2.2.2.2 Gas Plant Studies.3 A total of six gas plants were

screened in two studies: Four were screened by the EPA and two

by the American Petroleum Institute. Average emission factors

were developed, and information on the percentage of equipment

with screening values equal to or greater than 10,000 ppmv was

presented. The average factors include emissions of ethane and

methane, which are hydrocarbons but are not classified as VOC’s.

2.2.2.3 Revised Petroleum Industry Correlations and Emission

Factors. During the early-1990’s, new petroleum industry

equipment leak bagging data were collected and analyzed. The

Western States Petroleum Association (WSPA) and the American

Petroleum Institute (API) jointly commissioned the 1994 refinery

equipment leak report4 to evaluate fugitive emissions collected

from five petroleum refineries. The API also commissioned the

1993 marketing terminal equipment leak report,5 which included

bagging data from three marketing terminals, and, along with the

Gas Research Institute (GRI), jointly commissioned the 1993 and

1995 oil and gas production operations reports, which included

bagging data from 24 facilities.6,7 In addition to the bagging

data, screening data were also collected from 17 marketing

terminals8 and 24 oil and gas production facilities.6,7 Data

from gas/vapor, light liquid, and/or heavy liquid streams were

collected for these studies from non-flanged connectors, flanges,

open-ended lines, pumps, values, instruments, loading arms,

2-7
pressure relief valves, stuffing boxes, vents, compressors, dump

lever arms, diaphrams, drains, hatches, meters, and polished

rods.

A specific goal of the above studies was to collect high

quality data to enhance or replace the previously published

refinery correlations. As a result of the analyses discussed in

appendix C, the bagging data collected from refineries, marketing

terminals, and oil and gas production facilities during the

early-1990’s were combined to replace the previously published

refinery correlations with correlations applicable to the entire

petroleum industry. In addition, the new correlations apply

across all services for a given equipment type. The previously

published refinery correlations were specific to service and

equipment.

The screening data were used to develop average emission

factors for marketing terminals and for oil and gas production

operations. The average emission factors for oil and gas

production operations replace the gas plant factors published in

previous versions of this document and apply to light crude,

heavy crude, gas plant, gas production and off shore facilities.

No new screening data were available for refineries, therefore

the previously published refinery average emission factors remain

unchanged in this version of the protocol. Appendix C contains

more detailed information on how the new petroleum industry

correlations, marketing terminal emission factors, and oil and

gas production operations emission factors were developed.

2.2.2.4 Original SOCMI Average Emission Factors and

Correlations. In 1980, two studies were coordinated by the EPA

to collect data from SOCMI process units. These studies were the

24-Unit Study,9 and the Six-Unit Maintenance Study.10 In the

24-Unit Study, screening data were obtained from equipment

containing organic compounds at 24 individual chemical process

units representing a cross-section of the SOCMI. In the Six-Unit

Maintenance Study, bagging data were collected from six of the

process units within the 24-Unit Study to determine the effect of

maintenance on equipment leak emissions. Most of the bagging

2-8
data were collected from equipment with screening values above

1,000 ppmv. As part of the Six-Unit Maintenance Study,

correlations were developed for light liquid pumps, gas valves,

and light liquid valves.

The original SOCMI average emission factors were first

presented in the document "Fugitive Emission Sources of Organic

Compounds--Additional Information on Emissions, Emission

Reductions, and Costs."6 This document is referred to as the

Fugitive Emissions Additional Information Document (AID). In the

Fugitive Emissions AID, the data from the Refinery Assessment

Study were further analyzed to develop "leak/no leak" emission

factors. (A "leak" was defined as a screening value greater than

or equal to 10,000 ppmv.) With the exception of the factor for

gas valves, the original SOCMI average emission factors were

developed using (1) the leak/no-leak emission factors developed

from the Refinery Assessment Study data, and (2) the leak

frequencies from the SOCMI 24-Unit Study screening value data

set. This approach was based on statistical comparisons that

indicated that the most significant characteristic that

distinguished equipment in SOCMI facilities from that in

refineries was not the leak rate for a given screening value, but

rather the fraction of equipment that had screening values

greater than or equal to 10,000 ppmv.

Thus, the following equation was used to calculate the

original SOCMI average emission factors:

SOCMI Average Factor = (F × RLF) + (1 - F) × RNLF

where:

F = Fraction of sources from the 24-Unit Study that

screened greater than or equal to 10,000 ppmv;

RLF = Refinery leaking emission factor; and

RNLF = Refinery non-leaking emission factor.

For gas valves, the previously collected data suggested that

for a given screening value the leak rate at a SOCMI facility was

2-9
not statistically equivalent to the leak rate at a refinery.

Therefore, data from the Six-Unit Maintenance Study were used to

develop the gas valve average emission factor.

2.2.2.5 Revised SOCMI Emission Factors and Correlations. In

1987 and 1988, screening data were obtained from 19 ethylene

oxide and butadiene producers, and, in 1990, bagging data were

collected from 16 of these process units. Screening and bagging

data were collected from light liquid pumps, gas valves, light

liquid valves, and connectors. A specific goal of the program

was to bag equipment that had screening values less than

1,000 ppmv. The bagging data were combined with bagging data

previously collected in the Six-Unit Maintenance Study, and this

combined bagging data set was used to revise the SOCMI

correlations. Likewise, the new screening data were combined

with screening data previously collected in the 24-Unit Study,

and this combined screening data set was used with the revised

correlations to generate new SOCMI emission factors.

Appendix B.2 contains more detailed information on how the

revised SOCMI correlations and emission factors were developed.

2.3 APPROACHES FOR ESTIMATING EQUIPMENT LEAK EMISSIONS

In this section, each of the approaches for estimating

equipment leak emissions are discussed. The description of each

approach focuses on the basic method for estimating TOC

emissions. Each of the approaches are demonstrated in example

calculations contained in appendix A. Special topics at the end

of the chapter have been included to address how to estimate VOC

emissions when some of the organic compounds in the stream are

not classified as VOC’s and also how to speciate emissions for

individual chemicals from equipment containing a mixture.

2.3.1 Average Emission Factor Approach

One accepted approach for estimating emissions allows use of

average emission factors developed by the EPA in combination with

unit-specific data that are relatively simple to obtain. These

data include: (1) the number of each type of component in a unit

(valve, connector, etc.), (2) the service each component is in

(gas, light liquid, or heavy liquid), (3) the TOC concentration

2-10
of the stream (and VOC or HAP concentrations if speciation is to

be performed), and (4) the time period each component was in that

service. The average emission factors for SOCMI process units,

refineries, marketing terminals, and oil and gas production

operations are presented in tables 2-1, 2-2, 2-3, and 2-4

respectively. The SOCMI, marketing terminal, and oil and gas

production operations average emission factors predict total

organic compound emission rates, whereas the refinery average

factors predict non-methane organic compound emission rates.

Note that limited data has been collected on the leak rate of

agitators, and, until additional data are collected for emissions

from agitator seals, the average factor for light liquid pump

seals can be used to estimate emissions from agitators.

Although the average emission factors are in units of

kilogram per hour per individual source, it is important to note

that these factors are most valid for estimating emissions from a

population of equipment. The average factors are not intended to

be used for estimating emissions from an individual piece of

equipment over a short time period (i.e., 1 hour).

To estimate emissions using the Average Emission Factor

Approach, the concentration of TOC in weight fraction within the

equipment is needed because equipment with higher TOC

concentrations tend to have higher TOC leak rates. When using

the Average Emission Factor Approach, equipment should be grouped

into "streams" where all the equipment within the stream have

approximately the same TOC weight fraction.

To apply the average emission factors, use the following

equation to estimate TOC mass emissions from all of the equipment

in a stream of a given equipment type:

ETOC = FA × WFTOC × N

where:

ETOC = Emission rate of TOC from all equipment in

the stream of a given equipment type (kg/hr);

2-11
TABLE 2-1. SOCMI AVERAGE EMISSION FACTORS

Equipment type Service

Emission factora

(kg/hr/source)

Valves Gas

Light liquid

Heavy liquid

0.00597

0.00403

0.00023

Pump sealsb Light liquid

Heavy liquid

0.0199

0.00862

Compressor seals Gas 0.228

Pressure relief valves Gas 0.104

Connectors All 0.00183

Open-ended lines All 0.0017

Sampling connections All 0.0150

aThese factors are for total organic compound emission

rates.

bThe light liquid pump seal factor can be used to estimate the

leak rate from agitator seals.

2-12
TABLE 2-2. REFINERY AVERAGE EMISSION FACTORSa

Equipment type Service

Emission factor

(kg/hr/source)b

Valves Gas

Light liquid

Heavy liquid

0.0268

0.0109

0.00023

Pump sealsc Light liquid

Heavy liquid

0.114

0.021

Compressor seals Gas 0.636

Pressure relief valves Gas 0.16

Connectors All 0.00025

Open-ended lines All 0.0023

Sampling connections All 0.0150

aSource: Reference 2.

bThese factors are for non-methane organic compound

emission rates.

cThe light liquid pump seal factor can be used to estimate the

leak rate from agitator seals.

2-13
TABLE 2-3. MARKETING TERMINAL AVERAGE EMISSION FACTORS

Equipment type Service

Emission factor

(kg/hr/source)a

Valves Gas

Light Liquid

1.3E-05

4.3E-05

Pump seals Gas

Light Liquid

6.5E-05

5.4E-04

Others (compressors

and others)b

Gas

Light Liquid

1.2E-04

1.3E-04

Fittings (connectors

and flanges)c

Gas

Light Liquid

4.2E-05

8.0E-06

aThese factors are for total organic compound emission rates

(including non-VOC’s such as methane and ethane).

bThe "other" equipment type should be applied for any equipment

type other than fittings, pumps, or valves.

c"Fittings" were not identified as flanges or non-flanged

connectors; therefore, the fitting emissions were estimated by

averaging the estimates from the connector and the flange

correlation equations.

2-14
TABLE 2-4. OIL AND GAS PRODUCTION OPERATIONS AVERAGE EMISSION

FACTORS (kg/hr/source)

Equipment Type Servicea

Emission Factor

(kg/hr/source)b

Valves Gas

Heavy Oil

Light Oil

Water/Oil

4.5E-03

8.4E-06

2.5E-03

9.8E-05

Pump seals Gas

Heavy Oil

Light Oil

Water/Oil

2.4E-03

NA

1.3E-02

2.4E-05

Othersc Gas

Heavy Oil

Light Oil

Water/Oil

8.8E-03

3.2E-05

7.5E-03

1.4E-02

Connectors Gas

Heavy Oil

Light Oil

Water/Oil

2.0E-04

7.5E-06

2.1E-04

1.1E-04

Flanges Gas

Heavy Oil

Light Oil

Water/Oil

3.9E-04

3.9E-07

1.1E-04

2.9E-06

Open-ended lines Gas

Heavy Oil

Light Oil

Water/Oil

2.0E-03

1.4E-04

1.4E-03

2.5E-04

aWater/Oil emission factors apply to water streams in oil service

with a water content greater than 50%, from the point of origin

to the point where the water content reaches 99%. For water

streams with a water content greater than 99%, the emission rate

is considered negligible.

bThese factors are for total organic compound emission rates

(including non-VOC’s such as methane and ethane) and apply to

light crude, heavy crude, gas plant, gas production, and

off shore facilities. "NA" indicates that not enough data were

available to develop the indicated emission factor.

cThe "other" equipment type was derived from compressors,

diaphrams, drains, dump arms, hatches, instruments, meters,

pressure relief valves, polished rods, relief valves, and vents.

This "other" equipment type should be applied for any equipment

type other than connectors, flanges, open-ended lines, pumps, or

valves.

2-15
FA = Applicable average emission factor for the

equipment type (kg/hr/source);

FOR REFINERIES ONLY: The emission factor

"FA" must be adjusted to account for all

organic compounds in the stream because the

refinery factors are only valid for

non-methane organic compounds (percents up to

a maximum of 10 percent by weight methane are

permitted):

WFTOC

FA = FA × ;

WFTOC - WFmethane

WFTOC = Average weight fraction of TOC in the stream;

WFmethane = Average weight fraction of methane in the

stream; and

N = Number of pieces of equipment of the

applicable equipment type in the stream.

Note that the emission factor "FA" is defined differently for

refineries than for SOCMI, marketing terminals, or oil and gas

production operations when calculating TOC mass emissions. It is

necessary to adjust the "FA" term when applied to refineries,

because when the refinery factors were developed, the methane was

subtracted out of the organic total. Adjusting the "FA" term for

refineries is a way to correct for this. Two guidelines when

correcting the "FA" term when applied to refineries are as

follows:

The correction should only be applied to equipment

containing a mixture of organics and methane; and

The maximum correction for the methane weight fraction

should not exceed 0.10, even if the equipment contains

greater than 10 weight percent methane. (This reflects

that equipment in the Refinery Assessment Study1,2

typically contained 10 weight percent or less methane).

Thus, at a SOCMI process unit, if there were 100 gas valves

in a stream containing, on average, 90 weight percent TOC and

10 weight percent water vapor, emissions would be calculated as

follows:

2-16
ETOC = FA × WFTOC × N

= 0.00597 kg/hr/gas valve × 0.9 × 100 gas valves

= 0.54 kg/hr of VOC from gas valves in the stream

At a refinery, if there were 100 gas valves in a stream that,

on average, contained 80 weight percent non-methane TOC,

10 weight percent water vapor, and 10 weight percent methane

(thus, the TOC weight percent would be 90), emissions would be

calculated using the above equation as follows:

WFTOC

ETOC = FA × × WFTOC × N

WFTOC - WFmethane

= 0.0268 kg/hr/gas valve × (0.9/0.9-0.1) × 0.9 ×

100 gas valves

= 2.71 kg/hr of VOC from gas valves in the stream

If there are several streams at a process unit, the total TOC

emission rate for an equipment type is the sum of emissions from

each of the streams. The total emission rates for all of the

equipment types are summed to generate the process unit total TOC

emission rate from leaking equipment.

Assuming all of the organic compounds in the stream are

classified as VOC’s, the total VOC emission for each stream is

calculated as the sum of TOC emissions associated with each

specific equipment type in the stream. Section 2.4.6 discusses

an adjustment that can be made to predict the VOC emission rate

if some of the organic compounds in the stream are not classified

as VOC’s (such as methane and ethane).

As mentioned earlier, the average emission factors are not

intended to provide an accurate estimate of the emission rate

from a single piece of equipment. Rather, the average factors

are more appropriately applied to the estimation of emissions

from populations of equipment. Data indicate that the range of

possible leak rates from individual pieces of equipment spans

2-17
several orders of magnitude. As a result, the majority of total

emissions from a population of equipment at any given time will

normally occur from a small percentage of the total equipment.

The average emission factors account for the span of possible

leak rates, but, as a result, they are not necessarily an

accurate indication of the mass emission rate from an individual

piece of equipment.

Furthermore, the average emission factors do not reflect

different site-specific conditions among process units within a

source category. Site-specific factors can have considerable

influence on leak rates from equipment. Nevertheless, in the

absence of screening data, the average emission factors do

provide an indication of equipment leak emission rates from

equipment in a process unit.

2.3.2 Screening Ranges Approach

The Screening Ranges Approach (formerly known as the

leak/no-leak approach) offers some refinement over the Average

Emission Factor Approach, thereby allowing some adjustment for

individual unit conditions and operation. This approach is

included in this section primarily to aid in the analysis of old

datasets which were collected for older regulations that used

10,000 ppmv as the leak definition. This approach and the other

two remaining approaches require that screening data be collected

for the equipment in the process unit. The screening data are an

indication of leak rates. When applying this approach, it is

assumed that components having screening values greater than

10,000 ppmv have a different average emission rate than

components with screening values less than 10,000 ppmv.

This approach may be applied when screening data are

available as either "greater than or equal to 10,000 ppmv" or as

"less than 10,000 ppmv." Emission factors for SOCMI, refineries,

marketing terminals, and oil and gas production operations for

these two ranges of screening values are presented in tables 2-5,

2-6, and 2-7, and 2-8, respectively. As with the average

factors, the SOCMI, marketing terminal, and oil and gas

production operations screening range factors predict total

2-18
TABLE 2-5. SOCMI SCREENING RANGES EMISSION FACTORS

Equipment type Service

≥10,000 ppmv

Emission factor

(kg/hr/source)a

<10,000 ppmv

Emission factor

(kg/hr/source)a

Valves Gas

Light liquid

Heavy liquid

0.0782

0.0892

0.00023

0.000131

0.000165

0.00023

Pump sealsb Light liquid

Heavy liquid

0.243

0.216

0.00187

0.00210

Compressor

seals

Gas 1.608 0.0894

Pressure

relief valves

Gas 1.691 0.0447

Connectors All 0.113 0.0000810

Open-ended

lines

All 0.01195 0.00150

aThese factors are for total organic compound emission rates.

bThe light liquid pump seal factors can be applied to estimate

the leak rate from agitator seals.

2-19
TABLE 2-6. REFINERY SCREENING RANGES EMISSION FACTORSa

Equipment type Service

≥10,000 ppmv

Emission factor

(kg/hr/source)b

<10,000 ppmv

Emission factor

(kg/hr/source)b

Valves Gas 0.2626 0.0006

Light liquid 0.0852 0.0017

Heavy liquid 0.00023 0.00023

Pump sealsc Light liquid 0.437 0.0120

Heavy liquid 0.3885 0.0135

Compressor seals Gas 1.608 0.0894

Pressure relief

valves

Gas 1.691 0.0447

Connectors All 0.0375 0.00006

Open-ended lines All 0.01195 0.00150

aSource: Reference 6.

bThese factors are for non-methane organic compound emission

rates.

cThe light liquid pump seal factors can be applied to estimate

the leak rate from agitator seals.

2-20
TABLE 2-7. MARKETING TERMINAL SCREENING RANGES EMISSION FACTORS

Equipment

type Service

≥10,000 ppmv

Emission factor

(kg/hr/source)a

<10,000 ppmv

Emission factor

(kg/hr/source)a

Valves Gas

Light Liquid

NA

2.3E-02

1.3E-05

1.5E-05

Pump seals Light liquid 7.7E-02 2.4E-04

Other

(compressors

and others)b

Gas

Light liquid

NA

3.4E-02

1.2E-04

2.4E-05

Fittings

(connectors

and flanges)c

Gas

Light liquid

3.4E-02

6.5E-03

5.9E-06

7.2E-06

aThese factors are for total organic compound emission rates

(including non-VOC’s such as methane and ethane). "NA"

indicates that not enough data were available to develop the

indicated emission factor.

bThe "other" equipment type should be applied for any equipment

type other than fittings, pumps, or valves.

c"Fittings" were not identified as flanges or connectors;

therefore, the fitting emissions were estimated by averaging the

estimates from the connector and the flange correlation

equations.

2-21
TABLE 2-8. OIL AND GAS PRODUCTION OPERATIONS SCREENING RANGES

EMISSION FACTORS

Equipment type Serviceb

≥10,000 ppmv

Emission factor

(kg/hr/source)a

<10,000 ppmv

Emission factor

(kg/hr/source)a

Valves Gas

Heavy Oil

Light Oil

Water/Oil

9.8E-02

NA

8.7E-02

6.4E-02

2.5E-05

8.4E-06

1.9E-05

9.7E-06

Pump seals Gas

Heavy Oil

Light Oil

Water/Oil

7.4E-02

NA

1.0E-01

NA

3.5E-04

NA

5.1E-04

2.4E-05

Othersc Gas

Heavy Oil

Light Oil

Water/Oil

8.9E-02

NA

8.3E-02

6.9E-02

1.2E-04

3.2E-05

1.1E-04

5.9E-05

Connectors Gas

Heavy Oil

Light Oil

Water/Oil

2.6E-02

NA

2.6E-02

2.8E-02

1.0E-05

7.5E-06

9.7E-06

1.0E-05

Flanges Gas

Heavy Oil

Light Oil

Water/Oil

8.2E-02

NA

7.3E-02

NA

5.7E-06

3.9E-07

2.4E-06

2.9E-06

Open-ended lines Gas

Heavy Oil

Light Oil

Water/Oil

5.5E-02

3.0E-02

4.4E-02

3.0E-02

1.5E-05

7.2E-06

1.4E-05

3.5E-06

aThese factors are for total organic compound emission rates

(including non-VOC’s such as methane and ethane) and apply to

light crude, heavy crude, gas plant, gas production, and

offshore facilities. "NA" indicates that not enough data were

available to develop the indicated emission factor.

bWater/Oil emission factors apply to water streams in oil service

with a water content greater than 50%, from the point of origin

to the point where the water content reaches 99%. For water

streams with a water content greater than 99%, the emission rate

is considered negligible.

cThe "other" equipment type was derived from compressors,

diaphrams, drains, dump arms, hatches, instruments, meters,

pressure relief valves, polished rods, relief valves, and vents.

This "other" equipment type should be applied for any equipment

type other than connectors, flanges, open-ended lines, pumps, or

valves.

2-22
organic compound emissions, whereas the refinery screening range

factors predict non-methane organic compound emissions. Note

that there are not screening range factors for sampling

connections because emissions from sampling connections occur

when the line is purged, and, thus, are independent of any

screening value. Also, as with the average factors, the

screening range factors for light liquid pumps can be applied to

agitators.

The Screening Ranges Approach is applied in a similar manner

as the Average Emission Factor Approach in that equipment counts

are multiplied by the applicable emission factor. Also, for

refineries, the screening range emission factors must be adjusted

for methane in the equipment because when the refinery factors

were developed, the methane was subtracted out of the organic

total.

To calculate TOC emissions using the Screening Ranges

Approach, the following equation is used:

ETOC = (FG × NG) + (FL × NL)

where:

ETOC = TOC emission rate for an equipment type

(kg/hr);

FG = Applicable emission factor for sources with

screening values greater than or equal to

10,000 ppmv (kg/hr/source);

FOR REFINERIES ONLY: The emission factor "FG"

must be adjusted to account for all organic

compounds in the stream because the refinery

factors are only valid for non-methane

organic compounds (percents up to a maximum

of 10 percent by weight methane are

permitted):

WPTOC

FG = FG × ;

WPTOC - WPmethane

WPTOC = Average weight percent of TOC in the stream;

2-23
WPmethane = Average weight percent of methane in the

stream;

NG = Equipment count (specific equipment type) for

sources with screening values greater than or

equal to 10,000 ppmv;

FL = Applicable emission factor for sources with

screening values less than 10,000 ppmv

(kg/hr/source)

FOR REFINERIES ONLY: The emission factor

"FL" must be adjusted to account for all

organic compounds in the stream because the

refinery factors are only valid for

non-methane organic compounds (percents up to

a maximum of 10 percent by weight methane are

permitted):

WPTOC

FL = FL × ; and

WPTOC - WPmethane

NL = Equipment count (specific equipment type) for

sources with screening values less than

10,000 ppmv.

Assuming all of the organic compounds in the stream are

classified as VOC’s, the total VOC emission for each stream is

calculated as the sum of TOC emissions associated with each

specific equipment type in the stream. Section 2.4.6 discusses

an adjustment that can be made to predict the VOC emission rate

if some of the organic compounds in the stream are not classified

as VOC’s (such as methane and ethane).

The screening range emission factors are a better indication

of the actual leak rate from individual equipment than the

average emission factors. Nevertheless, available data indicate

that measured mass emission rates can vary considerably from the

rates predicted by use of these factors.

2.3.3 EPA Correlation Approach

This approach offers an additional refinement to estimating

emissions from equipment leaks by providing an equation to

predict mass emission rate as a function of screening value for a

particular equipment type. Correlations developed by the EPA

relating screening values to mass emission rates for SOCMI

2-24
process units and for petroleum industry process units are

presented in tables 2-9 and 2-10, respectively. Correlations for

the petroleum industry apply to refineries, marketing terminals

and oil and gas production operations. Figures 2-2 through 2-5

plot the correlations. Both the SOCMI and petroleum industry

correlations predict total organic compound emission rates.

Appendix B.1 contains additional information on the general

development of correlation equations. Additionally, appendix B.2

contains information about the development of the SOCMI

correlations and appendix C contains information about the

development of the petroleum industry correlations.

The EPA Correlation Approach is preferred when actual

screening values are available. Correlations can be used to

estimate emissions for the entire range of non-zero screening

values, from the highest potential screening value to the

screening value that represents the minimum detection limit of

the monitoring device. This approach involves entering the

non-zero, non-pegged screening value into the correlation

equation, which predicts the TOC mass emission rate based on the

screening value. Default zero emission rates are used for

screening values of zero ppmv and pegged emission rates are used

for "pegged" screening values (the screening value is beyond the

upper limit measured by the portable screening device).

Correlations for SOCMI are available for (1) gas valves;

(2) light liquid valves; (3) connectors; and (4) light liquid

pump seals. Correlations for the petroleum industry are

available for (1) valves; (2) connectors; (3) pumps; (4) flanges;

(5) open-ended lines; and (6) "others" (derived from instruments,

loading arms, pressure relief valves, stuffing boxes, and vents).

Limited bagging data for compressors and pressure relief

devices have been obtained at SOCMI plants. However, because

statistical tests performed as part of the Refinery Assessment

Study2 indicated that emissions from light liquid pumps,

compressors, and pressure relief valves could be expressed with a

single correlation, until additional data are collected, the

SOCMI equation for light liquid pump seals can be applied to

2-25
TABLE 2-9. SOCMI LEAK RATE/SCREENING VALUE CORRELATIONS

Equipment type Correlationa,b

Gas valves Leak rate (kg/hr) = 1.87E-06 × (SV)0.873

Light liquid valves Leak rate (kg/hr) = 6.41E-06 × (SV)0.797

Light liquid pumpsc Leak rate (kg/hr) = 1.90E-05 × (SV)0.824

Connectors Leak rate (kg/hr) = 3.05E-06 × (SV)0.885

aSV = Screening value in ppmv.

bThese correlations predict total organic compound emission

rates.

cThe correlation for light liquid pumps can be applied to

compressor seals, pressure relief valves, agitator seals, and

heavy liquid pumps.

2-26
TABLE 2-10. PETROLEUM INDUSTRY LEAK RATE/SCREENING VALUE

CORRELATIONSa

Equipment

type/service Correlationb,c

Valves/all Leak rate (kg/hr) = 2.29E-06 × (SV)0.746

Pump seals/all Leak rate (kg/hr) = 5.03E-05 × (SV)0.610

Othersd Leak rate (kg/hr) = 1.36E-05 × (SV)0.589

Connectors/all Leak rate (kg/hr) = 1.53E-06 × (SV)0.735

Flanges/all Leak rate (kg/hr) = 4.61E-06 × (SV)0.703

Open-ended lines/all Leak rate (kg/hr) = 2.20E-06 × (SV)0.704

aThe correlations presented in this table are revised petroleum

industry correlations.

bSV = Screening value in ppmv.

cThese correlations predict total organic compound emission

rates (including non-VOC’s such as methane and ethane).

dThe "other" equipment type was derived from instruments,

loading arms, pressure relief valves, stuffing boxes, and

vents. This "other" equipment type should be applied to any

equipment type other than connectors, flanges, open-ended

lines, pumps, or valves.

2-27
Figure 2-2. SOCMI Correlations relating total organic compound

(TOC) leak rate to screening value:

0 - 1,000 ppmv

2-28
Figure 2-3. SOCMI Correlations relating total organic compound

(TOC) leak rate to screening value:

1,000 - 1,000,000 ppmv

2-29
Figure 2-4. Petroleum Industry Correlations relating total

organic compound (TOC) leak rate to screening value:

1,000 - 1,000,000 ppmv

2-30
Figure 2-5. Petroleum Industry Correlations relating total

organic compound (TOC)leak rate to screening value:

1,000 - 1,000,000 ppmv

2-31
estimate emissions for compressor seals and pressure relief

valves in SOCMI process units. Because bagging data were limited

and the frequency of occurrence of some equipment types was

small, a correlation for an "other" equipment type was developed

for the petroleum industry correlations to apply to any equipment

type other than connectors, flanges, open-ended lines, pumps, or

valves.

Bagging data for agitator seals at petroleum industry and

SOCMI process units are unavailable at this time. Compared to

those equipment types that have correlations, agitators most

closely resemble light liquid pumps, and, for this reason, the

applicable light liquid pump correlation can be used to estimate

agitator emissions. Similarly, the SOCMI light liquid pump

correlation can be used to estimate emissions from SOCMI heavy

liquid pumps.

The "default-zero" leak rate is the mass emission rate

associated with a screening value of zero. (Note that any

screening value that is less than or equal to ambient

[background] concentration is considered a screening value of

zero.) The correlations mathematically predict zero emissions

for zero screening values. However, data collected by the EPA

show this prediction to be incorrect. Mass emissions have been

measured from equipment having a screening value of zero.

A specific goal when revising the SOCMI and petroleum industry

correlations was to collect mass emissions data from equipment

that had a screening value of zero. These data were used to

determine a default-zero leak rate associated with equipment with

zero screening values.

Table 2-11 lists the SOCMI default-zero leak rates and

table 2-12 presents the petroleum industry default-zero leak

rates for each of the equipment types with correlation equations.

These default-zero leak rates are applicable only when the

minimum detection limit of the portable monitoring instrument is

1 ppmv or less above background.

The portable monitoring device used to collect the

default-zero data was sufficiently sensitive to indicate a

2-32
TABLE 2-11. DEFAULT-ZERO VALUES: SOCMI PROCESS UNITS

Equipment type

Default-zero emission rate

(kg/hr/source)a

Gas valve 6.6E-07

Light liquid valve 4.9E-07

Light liquid pumpb 7.5E-06

Connectors 6.1E-07

aThe default zero emission rates are for total organic compounds

(including non-VOC’s such as methane and ethane).

bThe light liquid pump default zero value can be applied to

compressors, pressure relief valves, agitators, and heavy

liquid pumps.

2-33
TABLE 2-12. DEFAULT-ZERO VALUES: PETROLEUM INDUSTRY

Equipment type/service

Default-zero emission ratesa,b

(kg/hr/source)

Valves/all 7.8E-06

Pump seals/all 2.4E-05

Othersc/all 4.0E-06

Connectors/all 7.5E-06

Flanges/all 3.1E-07

Open-ended lines/all 2.0E-06

aDefault zero emission rates were based on the combined

1993 refinery and marketing terminal data only (default zero

data were not collected from oil and gas production

facilities).

bThese default zero emission rates are for total organic

compounds (including non-VOC’s such as methane and ethane).

cThe "other" equipment type was developed from instruments,

loading arms, pressure relief valves, stuffing boxes, vents,

compressors, and dump lever arms. This "other" equipment type

should be applied to any equipment type other than connectors,

flanges, open-ended lines, pumps, or valves.

2-34
screening value of 1 ppmv or less. In cases where a monitoring

instrument has a minimum detection limit greater than 1 ppmv, the

default-zero leak rates presented in tables 2-11 and 2-12 are not

applicable. For these cases, an alternative approach for

determining a default-zero leak rate is to (1) determine one-half

the minimum screening value of the monitoring instrument, and

(2) enter this screening value into the applicable correlation to

determine the associated default-zero leak rate.

The "pegged" emission rate is the mass emission rate

associated with a screening value that has "pegged" the meter on

the portable screening device (i.e. the screening value is beyond

the upper limit measured by the portable screening device). In

the case of a screening value pegged at 10,000 ppmv, a dilution

probe should be used to extend the upper limit of the portable

screening device to 100,000 ppmv. Thus, screening values can be

reported up to 100,000 ppmv before pegging the instrument and the

correlation equation can be used to estimate the mass emissions.

However, in the case of previously-collected data or in the

absence of a dilution probe, pegged readings of 10,000 ppmv are

sometimes reported. In such cases, the 10,000 ppmv pegged

emission rates can be used to estimate the mass emissions.

Table 2-13 presents the 10,000 ppmv and 100,000 ppmv pegged

emission rates for SOCMI process units and table 2-14 presents

the 10,000 ppmv and 100,000 ppmv pegged emission rates for

petroleum industry process units. These pegged emission rates

are to be used to estimate emissions when instrument readings are

pegged and a dilution probe is not used.

Assuming all of the organic compounds in the equipment are

classified as VOC’s, total VOC emissions for each equipment type

are calculated as the sum of emissions associated with each of

the screening values. Section 2.4.6 discusses a correction that

can be made to the predicted VOC emissions rate if some of the

organic compounds in the equipment are not classified as VOC’s

(such as methane and ethane).

To summarize the correlation approach, each equipment piece

with a screening value of zero is assigned the default-zero leak

2-35
TABLE 2-13. 10,000 PPMV AND 100,000 PPMV SCREENING VALUE PEGGED

EMISSION RATES FOR SOCMI PROCESS UNITS

Equipment type

10,000 ppmv pegged

emission rate

(kg/hr/source)a,b

100,000 ppmv pegged

emission rate

(kg/hr/source)a

Gas valves 0.024 0.11

Light liquid

valves

0.036 0.15

Light liquid pump

sealsb

0.14 0.62

Connectors 0.044 0.22

aThe SOCMI pegged emission rates are for total organic compounds.

bThe 10,000 ppmv pegged emission rate applies only when a

dilution probe cannot be used or in the case of

previously-collected data that contained screening values

reported pegged at 10,000 ppmv.

cThe light liquid pump seal pegged emission rates can be applied

to compressors, pressure relief valves, and agitators.

2-36
TABLE 2-14. 10,000 ppmv and 100,000 PPMV SCREENING VALUE PEGGED

EMISSION RATES FOR THE PETROLEUM INDUSTRY

Equipment

type/service

10,000 ppmv pegged

emission rate

(kg/hr/source)a,b

100,000 ppmv pegged

emission rate

(kg/hr/source)a

Valves/all 0.064 0.140

Pump seals/all 0.074 0.160c

Othersd/all 0.073 0.110

Connectors/all 0.028 0.030

Flanges/all 0.085 0.084

Open-ended lines/all 0.030 0.079

aThe petroleum industry pegged emission rates are for total

organic compounds (including non-VOC’s such as methane and

ethane).

bThe 10,000 ppmv pegged emission rate applies only when a

dilution probe cannot be used or in the case of

previously-collected data that contained screening values

reported pegged at 10,000 ppmv. The 10,000 ppmv pegged emission

rate was based on components screened at greater than or equal

to 10,000 ppmv; however, in some cases, most of the data could

have come from components screened at greater than 100,000 ppmv,

thereby resulting in similar pegged emission rates for both the

10,000 and 100,000 pegged levels (e.g., connector and flanges).

cOnly 2 data points were available for the pump seal

100,000 pegged emission rate; therefore the ratio of the pump

seal 10,000 pegged emission rate to the overall 10,000 ppmv

pegged emission rate was multiplied by the overall 10,000 ppmv

pegged emission rate to approximate the pump 100,000 ppmv pegged

emission rate.

dThe "other" equipment type was developed from instruments,

loading arms, pressure relief valves, stuffing boxes, vents,

compressors, dump lever arms, diaphrams, drains, hatches,

meters, and polished rods. This "other" equipment type should

be applied to any equipment type other than connectors, flanges,

open-ended lines, pumps, and valves.

2-37
rate. For all equipment with a non-zero screening value, the

screening value associated with each individual equipment piece

is entered into the applicable correlation to predict emissions.

It should be noted that each individual screening value must be

entered into the correlation to predict emissions for an

equipment piece. Do not average screening values and then enter

the average value into the correlation to estimate emissions.

Finally, each equipment piece with a screening value reported as

pegged is assigned the appropriate pegged emission rate.

2.3.4 Unit-Specific Correlation Approach

To develop unit-specific correlations screening value and

corresponding mass emissions data (i.e., bagging data) must be

collected from process unit equipment. (See chapter 4.0 for a

detailed discussion on the procedures for bagging equipment.)

The equipment selected for bagging should be screened at the time

of bagging. The mass emissions rate determined by bagging, and

the associated screening value, can then be used to develop a

leak rate/screening value relationship (i.e., correlation) for

that specific equipment type in that process unit. The

correlations must be developed on a process unit basis to

minimize the error associated with differing leak rate

characteristics between units.

If a unit-specific correlation is developed, as long as the

procedures for bagging discussed in chapter 4.0 are followed, it

is not necessary to demonstrate that the correlation is

statistically different from the EPA correlation for it to be

applied. However, before developing unit-specific correlations,

it may be desirable to evaluate the validity of the EPA

correlations to a particular process unit. As few as four leak

rate measurements of a particular equipment type in a particular

service can be adequate for this purpose. The measured emission

rates can be compared with the rates that would be predicted by

the EPA correlations to evaluate whether or not the EPA

correlations provide reasonable mass emission estimates. A

simple method of comparison is to determine if measured emission

rates are consistently less than or greater than what would be

2-38
predicted by the EPA correlation. If there is a consistent

trend, such as all of the measured leak rates being lower than

the rate predicted by the EPA correlation, the EPA correlation

may not provide reasonable emission estimates for the process

unit.

A more formal comparison is the Wilcoxon signed-rank test.

This test can be performed by comparing the logarithm of the

measured mass emission rates to the logarithm of the

corresponding rates predicted by the EPA correlation. The

absolute magnitude of the differences are then ranked (e.g., the

pair with the smallest difference is assigned a rank of 1, the

pair with the next smallest difference a rank of 2, etc.), and

the sum of the ranks associated with positive differences is

computed. For example, if four bags were measured and they each

predicted higher mass emission rates than the EPA correlation,

the value of the sum of the ranks associated with those pairs

with positive differences would equal:

1 + 2 + 3 + 4 = 10

On the other hand, if four bags were measured and three predicted

higher mass emission rates than the EPA correlation, but the one

with the greatest absolute difference predicted a lower rate than

the EPA correlation, then the sum of the positive ranks would

equal:

1 + 2 + 3 = 6. (Note: The sum of the negative ranks would

equal 4).

The value of the sum of the positive ranks can be compared to

given values on statistical tables to evaluate if there are

statistically significant differences between the measured rates

and the rates predicted by the EPA correlation.

However the comparison is performed, in cases where the EPA

correlations provide an adequate estimate of emissions, then the

potential increase in accuracy obtained by developing

2-39
unit-specific correlations may not be worth the effort.

Consideration should also be given to the typical screening value

measured at a process unit. If a process unit normally has very

low screening values, then the difference between the sum of unit

equipment leak emissions predicted by a unit-specific correlation

and the EPA correlation will likely be relatively small.

In developing new correlations, a minimum number of leak rate

measurements and screening value pairs must be obtained according

to the following methodology. First, equipment at the process

unit is screened so that the distribution of screening values at

the unit is known. Then, mass emissions data must be collected

from individual sources that have screening values distributed

over the entire range. The criteria for choosing these sources

is as follows. For each equipment type (i.e., valves, pumps,

etc.) and service (i.e., gas, light liquid, etc.), a random

sample of a minimum of six components should be chosen for

bagging from each of the following screening value ranges:

Screening Value Range (ppmv)

1 - 100

101 - 1,000

1,001 - 10,000

10,001 - 100,000

> 100,000

The requirement of six bags per screening value range is

based on the EPA experience with bagging components. There are

two primary reasons for the above requirement: (1) to be

confident in the representativeness of the data, and (2) to

accurately reflect the range of possible mass emission rates

associated with a given screening value. The importance of the

first reason is self-evident: The more data collected the better

the representativeness. The importance of the second reason is

that a given screening value does not necessarily have a "true"

emissions rate. For a single screening value, the mass emissions

may range over several orders of magnitude depending upon several

2-40
factors, including the equipment type (i.e., gate valve versus

ball valve versus plug valve, etc.) and operating parameters

(i.e., chemical handled, temperature, pressure, etc.). This

range of possible mass emission rates is accounted for when the

correlation is developed (see discussion on the scale bias

correction factor), and it is important to obtain enough data to

accurately reflect the range. If six sources are not available

in a particular screening value range, additional sources from

the nearest range should be tested so that a minimum of

30 emission rate/screening value pairs are obtained for each

source type. If 30 or more bags are collected, the process

unit-specific correlation can be used to estimate emissions

across the entire range of screening values (1 to

1,000,000 ppmv).

In some cases, it may be desirable to develop a correlation

with fewer than 30 bags. This can be accomplished by developing

a correlation that is not valid across the entire range of

screening values. Two alternatives are available: (1) to develop

a correlation valid for screening values ranging from 1 to

100,000 ppmv, or (2) to develop a correlation valid for screening

values ranging from 1 to 10,000 ppmv. These alternatives may be

preferable for process units with equipment that do not normally

have high screening values. An example of this type of process

unit is one that already has a leak detection and repair program

in place to prevent the release of odor-causing chemicals. At

this type of process unit, leaks may be quickly detected and

repaired.

For the first alternative, a minimum of 24 bags are required,

rather than 30, because sources with screening values greater

than 100,000 ppmv do not need to be bagged. Thus, a minimum of

six sources each should be chosen for bagging from each of the

screening ranges presented above except for the greater than

100,000 ppmv range. In the event that a source screens at

100,000 ppmv or greater, emissions can be estimated using

"pegged" emission rates shown in table 2-13 for SOCMI process

units, and in table 2-14 for petroleum industry process units.

2-41
For the second alternative, a minimum of 18 bags are

required, because sources screening greater than 10,000 ppmv do

not need to be bagged. Thus, a minimum of six sources should be

chosen for bagging from the 1 to 100 ppmv range, the 100 to

1000 ppmv range, and the 1,000 to 10,000 ppmv range. In the

event that a source screens at 10,000 ppmv or greater, emissions

can be estimated using the applicable greater than or equal to

10,000 ppmv pegged emission rate presented in table 2-13 for

SOCMI process units, or table 2-14 for petroleum industry process

units. An advantage of using the greater than or equal to

10,000 ppmv pegged emission rates is that several of the

available portable monitoring instruments have a maximum readout

of 10,000 ppmv, and to obtain a screening value from a source

screening at 10,000 ppmv, it is necessary to install a dilution

probe. However, if the greater than or equal to 10,000 ppmv

factor is used, installing a dilution probe is not necessary for

this alternative.

The above groupings and recommended number of sources are

given as guidelines. They are based on experience in measuring

leak rates and developing leak rate/screening value correlations.

Other source selection strategies can be used if an appropriate

rationale is given.

With mass emissions data and screening values, leak

rate/screening value correlations can be generated using the

following methodology. Least-squares regression analyses are

completed for each equipment type/service, regressing the log of

the leak rate on the log of the screening concentration,

according to:

Log10 (leak rate [in kg/hr]) = β0 + β1 × Log10 (SV)

where:

β0, β1 = Regression constants; and

SV = Screening value.

2-42
Note that the results are the same whether the base 10 or natural

logarithm are used (see appendix B). The equations presented

here are written assuming the base 10 logarithm is used. All

analyses should be conducted using logarithms of both the leak

rate and screening value because this type of data has been shown

to be log-normally distributed. A scale bias correction factor

(SBCF) is required in transforming the equation in the log-scale

back to the original units. The transformed equation is the

unit-specific correlation, and is expressed as:

where:

Leak rate = SBCF x 10β0 x SVβ1

Leak rate = Emission rate of TOC’s from the individual

equipment piece (kg/hr);

SBCF = Scale bias correction factor;

β0,β1 = Regression constants; and

SV = Screening value.

The SBCF is a function of the mean square error of the

correlation in log space. The greater the range of possible

emission rates for a given screening value, the greater the SBCF

will be. The purpose of the SBCF is to reflect this range when

transforming the correlation out of log space. When regressed in

log space, in general, approximately half of the data points will

lie above the correlation line and half will lie below it, and,

for a given screening value, the correlation will pass through

the mean log leak rate (i.e., the geometric mean). Thus, one way

of thinking of the correlation in log space is that it predicts

the geometric mean emissions rate across the range of screening

values. However, the geometric mean always underestimates the

arithmetic mean.

A simplified hypothetical example will help demonstrate this

point: For a screening value of 500,000 ppmv, three bagging data

points were obtained with mass emission rates of 0.1 kg/hr,

2-43
1 kg/hr, and 10 kg/hr. In log space, these emission rates

correspond to log10 (0.1) = -1, log10 (1) = 0, and

log10 (10) = 1, respectively. Thus, the geometric mean of these

three points is (-1+0+ 1)/3 = 0. Directly transforming this

geometric mean to normal space predicts an emission rate for a

screening value of 500,000 ppmv of 100 = 1 kg/hr, whereas the

arithmetic mean of the emission rates is

(0.1 + 1 + 10)/3 = 3.7 kg/hr. From this example, it can be seen

that the geometric mean underestimates the arithmetic mean.

Thus, if the correlation was directly transformed, it would

underestimate the true average emission rate associated with a

given screening value, and, for this reason, the SBCF is

necessary to transform the correlation out of log space.

In appendix B, additional details on developing a

process-unit specific correlation are presented. Appendix B also

contains information on development of the revised SOCMI

correlations.

2.4 SPECIAL TOPICS

There are several special topics relevant to estimating

equipment leak emissions that are not specific to any one of the

four approaches that have been described. These special topics

are discussed in this section:

Speciating emissions;

Using response factors;

Monitoring instrument type and calibration gas;

Estimating emissions for equipment not screened (when

other screening data are available);

Using screening data collected at several different

times;

Estimating VOC emission rates from equipment containing

organic compounds not classified as VOC’s (such as

methane and ethane); and

Estimating equipment leak emissions of inorganic

compounds.

2-44
Each of these topics above are addressed in the following

sections.

2.4.1 Speciating Emissions

For each of the four approaches for estimating equipment leak

emissions, the equations presented are used to estimate TOC

emissions for estimating equipment leak emissions. Often, in a

chemical-handling facility, material in equipment is a mixture of

several chemicals, and, in some cases, it may be necessary to

estimate emissions of a specific VOC in the mixture. The

following equation is used to speciate emissions from a single

equipment piece:

Ex = ETOC × (WPx/WPTOC)

where:

Ex = The mass emissions of organic chemical "x" from

the equipment (kg/hr);

ETOC = The TOC mass emissions from the equipment

(kg/hr) calculated from either the Average

Emission Factor, Screening Ranges, Correlation,

or Unit-Specific Correlation approaches;

WPx = The concentration of organic chemical "x" in the

equipment in weight percent; and

WPTOC = The TOC concentration in the equipment in weight

percent.

An assumption in the above equation is that the weight percent of

the chemicals in the mixture contained in the equipment will

equal the weight percent of the chemicals in the leaking

material. In general, this assumption should be accurate for

single-phase streams containing (1) any gas/vapor material, or

(2) liquid mixtures containing constituents of similar

volatilities.

If the material in the equipment piece is a liquid mixture of

constituents with varying volatilities, in certain cases this

assumption may not be correct. Whether or not the assumption is

valid for a liquid mixture of varying volatilities depends on the

physical mechanism of how the leakage occurs from the equipment.

2-45
If the physical mechanism is one in which the liquid "flashes"

before it leaks from the equipment, the leaking vapor may contain

a higher concentration of the more volatile constituents than is

contained in the liquid mixture. On the other hand, if the

mechanism is one in which the liquid material leaks from the

equipment and then evaporates, the assumption that the weight

percent of each constituent in the liquid will equal the weight

percent of each constituent in the vapor is valid. There are no

clear guidelines to determine what mechanism is taking place for

any given piece of equipment; for this reason, unless there is

information to suggest otherwise, it should be assumed that the

leaking vapor has the same concentrations as the liquid.

For those cases where it is suspected the leaking vapor will

have different concentrations than the liquid, engineering

judgement should be used to estimate emissions of individual

chemical species. An example might be equipment containing

material in two phases. Another hypothetical example is a case

where equipment contain a liquid mixture of two constituents with

one of the constituents having a very low vapor pressure and the

other a much higher vapor pressure. Leaks may occur from the

equipment such that the constituent with higher vapor pressure

volatilizes to the atmosphere, but the constituent with lower

vapor pressure is washed to the waste water treatment system

prior to volatilization.

2.4.2 Using Response Factors

A correction factor that can be applied to a screening value

is a response factor (RF) that relates the actual concentration

to the measured concentration of a given compound, using a

specific reference gas. As stated earlier, screening values are

obtained by using a portable monitoring instrument to detect

VOC’s at an equipment piece leak interface. An "ideal" screening

RF value is one that is equal to the actual concentration of

VOC’s at the leak interface. However, portable monitoring

instruments used to detect TOC concentration do not respond to

different TOC’s equally. (This is discussed in more detail in

chapter 3.0). To demonstrate this point, consider a monitoring

2-46
instrument calibrated using a reference gas. If the instrument

is calibrated correctly and is used to measure the concentration

of the gas with which it has been calibrated, it will indicate

the actual concentration. However, when used to measure other

gases for which the monitoring instrument is more or less

sensitive than the calibration gas, it will not indicate the

actual concentration. To correct for this, RF’s have been

developed. The RF is calculated using the equation:

RF = AC/SV

where:

RF = Response factor;

AC = Actual concentration of the organic compound (ppmv);

and

SV = Screening value (ppmv).

The value of the RF is a function of several parameters.

These parameters include the monitoring instrument, the

calibration gas used to calibrate the instrument, the compound(s)

being screened, and the screening value.

The correlations presented in this chapter have been

developed primarily from screening value/mass emission data pairs

collected from equipment containing compounds that had RF’s less

than three. Thus, for cases in which a calibrated instrument is

used to measure concentrations of a compound for which that

instrument has an RF of three or less, reasonably accurate

emission estimates can be obtained directly without adjusting the

screening value. However, for a case in which a compound has an

RF greater than three for the calibrated instrument, the

emissions estimated using the unadjusted screening value will

generally underestimate the actual emissions. The EPA recommends

that if a compound (or mixture) has an RF greater than three,

then the RF should be used to adjust the screening value before

it is used in estimating emissions.

2-47
A detailed listing of published RF’s is contained in

appendix D. These RF’s were developed by injecting a known

concentration of a pure compound into a monitoring instrument and

comparing that actual concentration to the instrument readout

(i.e., screening value).

As an example of applying a RF, consider chloroform. From

table D-2 in appendix D, it can be seen that the RF for

chloroform at an actual concentration of 10,000 ppmv is equal to

4.48 for a Foxboro OVA-108 monitoring instrument calibrated with

methane. Thus, when the actual concentration of chloroform is

10,000 ppmv, the instrument will read 10,000 ppmv divided by

4.48, which equals 2,230 ppmv. If the measured value for

chloroform was directly entered into the correlation, it would

tend to underestimate emissions. (Note that when the RF is less

than 1 the unadjusted screening value will tend to overestimate

actual emissions.)

The RF’s in appendix D are for pure compounds. Those RF’s

can be used to estimate the RF for a mixture using the equation:

where:

RFm = 1

n

i 1

xi/RFi

RFm = Response factor of the mixture;

n = Number of components in the mixture;

xi = Mole fraction of constituent i in the mixture; and

RFi = Response factor of constituent i in the mixture.

This equation is derived in appendix A.

An alternative approach for determining the RF of a pure

compound or a mixture is to perform analysis in a laboratory to

generate the data used to calculate a RF. The approach for

generating these data in the laboratory is described in

chapter 3.0. The approach involves injecting samples of a known

concentration of the material of interest into the actual

portable monitoring instrument used to obtain the screening

values and calculating the RF based on the instrument readout.

2-48
In general, calculating the RF by performing analysis on site

will give the most accurate RF information, since, among other

factors, RF’s have been shown to be a function of the individual

monitoring instrument.

Ideally, when using screening values to estimate equipment

leak emissions, the RF would be equal to 1, and, in this way, the

screening value would be the actual concentration. However,

because RF’s are a function of several parameters, this cannot

normally be achieved. Response factors can be used to correct

all screening values, if so desired. To evaluate whether a RF

correction to a screening value should be made, the following

three steps can be carried out.

(1) For the combination of monitoring instrument and

calibration gas used, determine the RF’s of a given

material at an actual concentration of 500 ppmv and

10,000 ppmv. (See appendix D; in some cases, it may not

be possible to achieve an actual concentration of

10,000 ppmv for a given material. In these cases, the

RF at the highest concentration that can be safely

achieved should be determined.)

(2) If the RF’s at both actual concentrations are below 3,

it is not necessary to adjust the screening values.

(3) If either of the RF’s are greater than 3, then the EPA

recommends an RF be applied for those screening values

for which the RF exceeds 3.

One of the following two approaches can be applied to correct

screening values:

(1) Use the higher of either the 500 ppmv RF or the

10,000 ppmv RF to adjust all screening values.

(2) Generate a response factor curve to adjust the

screening values.

A RF curve can be generated in one of two ways. The simplest

way is to assume that the RF value is a linear function of the

screening value. The first step to generate a line relating

screening value to RF is to convert the RF at the actual

concentration to the RF at the associated screening value. This

is done by dividing the RF by the actual concentration to get the

associated screening value. Thus, if, at an actual concentration

2-49
of 10,000 ppmv, an instrument has a RF of 5, this corresponds to

a screening value of 2,000 ppmv (i.e., 10,000 ppmv divided by 5).

This procedure is implemented at both actual concentrations of

10,000 ppmv and 500 ppmv, and a line is drawn between the RF’s at

each associated screening value. This line can then be used to

estimate the RF at any given screening value. (See appendix A

for a demonstration of this procedure.) The line should not be

extrapolated for screening values beyond the endpoints. For

these screening values, the endpoint RF should be applied.

For some materials, the RF is nonlinear as the screening

value increases. For these materials, RF’s at several screening

values can be estimated by collecting data in a laboratory, as

mentioned earlier. The RF/screening value relationship can then

be generated by fitting a curve through the data pairs.

When an RF is used, the screening value is multiplied by the

RF before mass emissions are estimated. Thus, if a screening

value is 3,000 ppmv and the associated RF is 4, then the

screening value must be adjusted to 12,000 ppmv (i.e., 3,000

multiplied by 4) before mass emissions are predicted.

It should be noted that if it is possible to calibrate the

monitoring instrument with the material contained in the

equipment that is being screened, the RF should equal 1. Thus,

theoretically, the screening values will equal the actual

concentration, and no RF adjustment will be necessary. If it is

necessary to apply RF’s, site personnel should use engineering

judgement to group process equipment into streams containing

similar compounds. All components associated with a given stream

can then be assigned the same RF, as opposed to calculating an RF

for each individual equipment piece.

2.4.3 Monitoring Instrument Type and Calibration Gas

When the correlations presented in section 2.3 were

developed, in general, for each of the source categories, the

data were collected using a specific type of monitoring

instrument calibrated with a specific calibration gas. The

correlations are intended to relate actual concentration to mass

emissions. For this reason, screening values obtained from any

2-50
combination of monitoring instrument and calibration gas can be

entered directly into the correlations as long as the screening

values are an indication of actual concentration. If the

screening values are not an indication of the actual

concentration, the guidelines set forth in the previous section

on RF’s can be applied to correct the screening values

(i.e., screening values should be adjusted if the RF is greater

than 3). Otherwise, it is not necessary to correct screening

values to account for the instrument type and calibration gas

that were used to develop the correlation curves developed by

the EPA.

2.4.4 Estimating Emissions for Equipment Not Screened

Often, screening data cannot be collected for all of the

equipment pieces in a process unit. In some cases, equipment are

difficult or unsafe to screen. Difficult or unsafe to screen

equipment must be included in the equipment counts. For these

equipment pieces, the average emission factors must be used to

estimate emissions.

In other cases, it is not possible to screen every equipment

piece due to cost considerations. This is particularly true for

connectors. Appendix E provides criteria for determining how

many connectors must be screened to constitute a large enough

sample size to identify the screening value distribution for

connectors. If the criteria in appendix E are met, the average

emission rate for connectors that were screened can be applied to

connectors that were not screened. It should be noted that if

connectors must be included in a leak detection and repair

program as part of an equipment leaks standard, then all

connectors must be screened. For equipment types other than

connectors, if they are not monitored, the Average Emission

Factor approach should be used to estimate emissions.

2.4.5 Using Screening Data Collected at Several Different

Times

When screening data is collected and used to estimate

emissions, the emissions estimate represents a "snapshot" of

emissions at the time the screening data were obtained. Over

2-51
time, it is possible that more screening data will be collected,

and that for individual equipment pieces, several screening

values will have been obtained at different time periods. For

example, if quarterly monitoring is performed on a valve, in an

annual period four screening values will be obtained from the

valve. The annual emissions from the valve should be calculated

by determining the emissions for each quarter based on the

operational hours for the quarter, and summing the quarterly

emissions together to arrive at emissions for the entire year.

See appendix A for an example of estimating emissions from an

equipment piece for which more than one screening value has been

obtained.

2.4.6 Estimating VOC Emission Rates from Equipment Containing

Non-VOC’s

Some organic compounds not classified as VOC’s can be

detected by the screening instrument. Because the compounds are

detected, the emissions associated with the screening value will

include emissions of the "non-VOC’s." The two key organic

compounds not classified as VOC’s are methane and ethane, but

other organic compounds not classified as VOC’s include methylene

chloride, 1,1,1-trichloroethane, and several chlorofluorocarbons.

An approach very similar to that outlined in section 2.4.1

(Speciating Emissions) is used to estimate VOC emissions from

equipment containing these non-VOC’s mixed with VOC’s.

Once TOC emissions have been estimated by using either the

Average Emission Factor, the Screening Ranges, the Correlation,

or the Unit-Specific Correlation approaches, the VOC emissions

from a group of equipment containing similar composition can be

calculated using the equation:

EVOC = ETOC × (WPVOC/WPTOC)

where:

EVOC = The VOC mass emissions from the equipment

(kg/hr);

ETOC = The TOC mass emissions from the equipment

(kg/hr) calculated form either the Average

2-52
Emission Factor, Screening Ranges, Correlation,

or Unit-Specific Correlation approaches;

WPVOC = The concentration of VOC in the equipment in

weight percent;

WPTOC = The TOC concentration in the equipment in weight

percent.

2.4.7 Estimating Equipment Leak Emissions of Inorganic

Compounds

The majority of data collected for estimating equipment leak

emissions has been for TOC’s or VOC’s and not for inorganic

compounds. Accordingly, the emission factors and correlations

presented in section 2.3 are not intended to be applied for the

used of estimating emissions of inorganic compounds. However, in

some cases, there may be a need to estimate equipment leak

emissions of inorganic compounds--particularly for those that

exist as a gas/vapor or for those that are volatile. Some

examples of inorganic compounds include sulfur dioxide, ammonia,

and hydrochloric acid.

The best way to estimate equipment leak emissions of

inorganic compounds would be to develop unit-specific

correlations as described in section 2.3.4. To do this, it would

be necessary to obtain a portable monitoring instrument that

could detect the inorganic compounds. If it is not possible to

develop a unit-specific correlation, but a portable monitoring

instrument (or some other approach) can be used to indicate the

actual concentration of the inorganic compound at the equipment

leak interface, then the "screening values" obtained with this

instrument can be entered into the applicable correlations

presented in section 2.3.3 to estimate emissions. Alternatively,

the equal to or greater than 10,000 ppmv, or the less than

10,000 ppmv emission factors could be applied. In the event that

there is no approach that can be used to estimate the

concentration of the inorganic compound at the leak interface,

then in the absence of any other data, the average emission

factors can be used.

2-53
2.5 REFERENCES

1. Radian Corporation. Assessment of Atmospheric Emissions from

Petroleum Refining: Volume 4. Appendices C, D, E. Prepared

for U.S. Environmental Protection Agency. Research Triangle

Park, NC. Publication No. EPA-600/2-80-075d. July 1980.

2. Wetherhold, R.G., L.P. Provost, and C.D. Smith (Radian

Corporation). Assessment of Atmospheric Emissions from

Petroleum Refining: Volume 3. Appendix B. Prepared for

U.S. Environmental Protection Agency. Research Triangle

Park, NC. Publication No. EPA-600/2-80-075c. April 1980.

3. DuBose, D.A., J.I. Steinmetz, and G.E. Harris (Radian

Corporation). Frequency of Leak Occurrence and Emission

Factors for Natural Gas Liquid Plants. Final Report.

Prepared for U.S. Environmental Protection Agency. Research

Triangle Park, NC. EMB Report No. 80-FOL-1. July 1982.

4. 1993 Study of Refinery Fugitive Emissions from Equipment

Leaks, Volumes I, II, and III, Radian DCN No. 93-209-081-02,

Radian Corporation, Prepared for Western States Petroleum

Association, Glendale, CA, and American Petroleum Institute,

Washington, D.C., 1994.

5. Development of Fugitive Emission Factors and Emission

Profiles for Petroleum Marketing Terminals, Volumes I and II,

API 4588, Radian Corporation, Prepared for American Petroleum

Institute, 1993.

6. Fugitive Hydrocarbon Emissions from Oil and Gas Production

Operations, API 4589, Star Environmental, Prepared for

American Petroleum Institute, 1993.

7. Emission Factors for Oil and Gas Production Operations,

API 4615, Star Environmental, Prepared for American Petroleum

Institute, 1995.

8. Letter from Robert Strieter, API, to David Markwordt,

U.S. EPA, regarding the submittal of gasoline distribution

facility fugitive equipment screening data. April 26, 1994.

9. Blacksmith, J.R., et al. (Radian Corporation.)

Problem-Oriented Report: Frequency of Leak Occurrence for

Fittings in Synthetic Organic Chemical Plant Process Units.

Prepared for U.S. Environmental Protection Agency. Research

Triangle Park, NC. Publication No. EPA-600/2-81-003.

September 1980.

10. Langley, G.J. and R.G. Wetherhold. (Radian Corporation.)

Evaluation of Maintenance for Fugitive VOC Emissions Control.

2-54
Prepared for U.S. Environmental Protection Agency. Research

Triangle Park, NC. Publication No. EPA-600/S2-81-080.

May 1981.

11. U.S. Environmental Protection Agency. Fugitive Emission

Sources of Organic Compounds - Additional Information of

Emissions, Emission Reductions, and Costs (section 2).

Research Triangle Park, NC. Publication

No. EPA-450/3 82-010. April 1982.

2-55
3.0 SOURCE SCREENING

3.1 INTRODUCTION

This chapter presents procedures for screening equipment

components with a portable volatile organic compound (VOC)

analyzer. When performing source screening, the portable

analyzer probe opening is placed at the leak interface of the

equipment component to obtain a "screening" value. The screening

value is an indication of the concentration level of any leaking

material at the leak interface. A screening value is not a

direct measure of mass emissions rate, but, as discussed in

chapter 2.0, can be entered into a mass emissions/screening value

correlation equation to estimate mass emissions.

This chapter is divided into two sections. The first section

provides a description of the portable analyzers that can be used

when conducting screening surveys. Operating principles of the

analyzers and performance criteria and specifications in the EPA

Reference Method 21 (the method describing the use of portable

VOC analyzers)1 are described, and the use of monitoring devices

that do not meet the EPA Reference Method 21 requirements is

discussed. The second section presents the protocol for

successfully conducting a screening program. This section

includes methods to identify components to be included in the

screening program, a discussion on the development of a

systematic approach for performing the screening survey, the

protocol for screening each of the equipment types, and

recommendations for collecting and handling data.

3-1
3.2 MONITORING INSTRUMENTS

A number of portable VOC detection devices have the potential

to measure the concentration level at the leak interface of

equipment. Any analyzer can be used, provided it meets the

specifications and performance criteria set forth in the EPA

Reference Method 21, section 3.0.1. Reference Method 21 is

included in this document as appendix F.

In general, portable VOC monitoring instruments are equipped

with a probe that is placed at the leak interface of a piece of

equipment. A pump within the instrument draws a continuous

sample of gas from the leak interface area to the instrument

detector. The instrument response is a screening value--that is,

a relative measure of concentration level. The screening value

is in units of parts per million by volume (ppmv). However, the

screening value does not necessarily indicate the actual total

concentration at the leak interface of the compound(s) being

detected because the sensitivity of instruments vary for

different compounds. As discussed in section 2.4.2, response

factors (RF’s) relate actual concentration of a compound to the

observed concentration from the detector. Before a monitoring

instrument is used, it must first be calibrated using a reference

gas containing a known compound at a known concentration.

Methane and isobutylene are frequently used reference compounds.

3.2.1 Operating Principles and Limitations of Portable VOC

Detection Devices

Monitoring instruments operate on a variety of detection

principles, with the three most common being ionization, infrared

absorption, and combustion. Ionization detectors operate by

ionizing the sample and then measuring the charge (i.e., number

of ions) produced. Two methods of ionization currently used are

flame ionization and photoionization. Each of these detector

types are briefly described below.

A standard flame ionization detector (FID) theoretically

measures the total carbon content of the organic vapor sampled,

but many other factors influence the FID readout. Although

carbon monoxide and carbon dioxide (CO2) do not produce

3-2
interferences, FID’s react to water vapor at a low sensitivity.

Furthermore, erratic readings may result if water condenses in

the sample tube. A filter is used to remove particulate matter

from the sample. Certain portable FID instruments are equipped

with gas chromatograph (GC) options making them capable of

measuring total gaseous non-methane organics or individual

organic components. Certain organic compounds containing

nitrogen, oxygen, or halogen atoms give a reduced response when

sampled with an FID, and the FID may not respond to some organic

compounds.

Photoionization detectors use ultraviolet light (instead of a

flame) to ionize organic vapors. As with FID’s, the detector

response varies with the functional group in the organic

compounds. Photoionization detectors have been used to detect

equipment leaks in process units in the SOCMI, especially for

certain compounds, such as formaldehyde, aldehydes, and other

oxygenated compounds, which will not give a satisfactory response

on a FID or combustion-type detector.

Nondispersive infrared (NDIR) instruments operate on the

principle of light absorption characteristics of certain gases.

These instruments are usually subject to interference because

other gases, such as water vapor and CO2, may also absorb light

at the same wavelength as the compound of interest. These

detectors are generally used only for the detection and

measurement of single components. For this type of detection,

the wavelength at which a certain compound absorbs infrared

radiation is predetermined and the device is preset for that

specific wavelength through the use of optical filters. For

example, if set to a wavelength of 3.4 micrometers, infrared

devices can detect and measure petroleum fractions, including

gasoline and naphtha.

Combustion analyzers are designed either to measure the

thermal conductivity of a gas or to measure the heat produced by

combustion of the gas. The most common method in which portable

VOC detection devices are used involves the measurement of the

heat of combustion. These detection devices are referred to as

3-3
hot wire detectors or catalytic oxidizers. Combustion analyzers,

like most other detectors, are nonspecific for gas mixtures. In

addition, combustion analyzers exhibit reduced response (and, in

some cases, no response) to gases that are not readily combusted,

such as formaldehyde and carbon tetrachloride.

3.2.2 Specifications and Performance Criteria of Portable VOC

Detection Devices

As previously stated, any portable analyzer may be used as a

screening device, provided it meets the specifications and the

performance criteria called for in the EPA Reference Method 21.

(See appendix F.) Reference Method 21 specifies the requirements

that must be met when a facility is collecting screening data to

comply with a regulation. The requirements of the EPA Reference

Method 21 are also applicable when screening data are collected

for the sole purpose of estimating emissions. When the

requirements of Reference Method 21 refer to a "leak definition,"

this is the screening value indicating that a piece of equipment

is leaking as defined in the applicable regulation. If screening

data are collected for the sole purpose of estimating emissions,

the equivalent to the "leak definition" concentration in the text

that follows is the highest screening value (i.e., 10,000 ppmv)

that the monitoring instrument can readout.

Reference Method 21 requires that the analyzer meet the

following specifications:1

• The VOC detector should respond to those organic

compounds being processed (determined by the RF);

• Both the linear response range and the measurable range

of the instrument for the VOC to be measured and the

calibration gas must encompass the leak definition

concentration specified in the regulation;

• The scale of the analyzer meter must be readable to

± 2.5 percent of the specified leak definition

concentration;

• The analyzer must be equipped with an electrically

driven pump so that a continuous sample is provided at a

nominal flow rate of between 0.1 and 3.0 liters per

minute;

3-4
• The analyzer must be intrinsically safe for operation in

explosive atmospheres; and

The analyzer must be equipped with a probe or probe

extension for sampling not to exceed .25 inch in outside

diameter, with a single end opening for admission of

sample.

Note that the suction flow rate span allowed by Reference

Method 21 is intended to accommodate a wide variety of

instruments, and manufacturers guidelines for appropriate suction

flow rate should be followed.

In addition to the above specifications, criteria for the

calibration gases to be used are specified. A minimum of two

calibration gases are required for analyzer performance

evaluation. One is a "zero" gas, which is defined as air with

less than 10 ppmv VOC; the other calibration gas, or reference

gas, uses a specified reference compound in an air mixture. The

concentration of the reference compound must approximately equal

the leak definition specified in the regulation. If cylinder

calibration gas mixtures are used, they must be analyzed and

certified by the manufacturer to be within ± 2 percent accuracy.

The shelf life must also be specified. Calibration gases can

also be prepared by the user as long as they are accurate to

within ± 2 percent.

The instrument performance criteria that each analyzer must

meet are presented in table 3-1 and discussed in greater detail

in the following sections.

3.2.2.1 Response Factor. The sensitivity of an analyzer

varies, depending on the composition of the sample and

concentration of VOC detected. The RF quantifies the sensitivity

of the analyzer to each compound. The RF is defined by:

An RF must be determined for each compound that is to be

RF = Actual Concentration of Compound

Observed Concentration from Detector

measured. Response factors may be determined either by testing

or from referenced sources. (The RF’s for many commonly screened

compounds are presented in appendix D.) The RF tests are

3-5
TABLE 3-1. PERFORMANCE CRITERIA FOR PORTABLE VOC DETECTORSa

Criteria Requirement Time interval

Instrument

response factor

Must be <10 unless

correction curve is

used

One time, before

detector is put in

service.

Instrument

response time

Must be ≤30 seconds One time, before

detector is put in

service. If

modification to sample

pumping or flow

configuration is made,

a new test is required.

Calibration

precision

Must be ≤10 percent

of calibration gas

value

Before detector is put

in service and at

3-month intervals or

next use, whichever is

later.

aSource: Reference 1.

3-6
required before placing the analyzer into service, but do not

need to be repeated. The RF for each compound to be measured

must be less than 10 for an analyzer to be acceptable for use in

a screening program. According to Reference Method 21, the RF

can either be measured in the laboratory using a prepared gas

concentration at 80 percent of the applicable leak definition, or

it can be taken from values published in the literature. When no

instrument is available that meets this criteria when calibrated

with the reference compound specified in the applicable

regulation, the available instrument may be calibrated with one

of the VOC’s to be measured. However, the analyzer RF must still

be less than 10 for each VOC to be measured.

As discussed in section 2.4.2, RF’s depend on several

parameters, including the compound, the screening value, the

monitoring instrument, and the calibration gas. In chapter 2.0,

guidance was provided on when and how to apply RF’s for

estimating emissions. Methods were presented on calculating an

RF for a given chemical at a screening value other than one for

which data were published. Methods were also presented for

calculating RF’s for mixtures.

In this chapter, several additional issues pertaining to RF’s

are discussed. These issues are (1) the consideration of RF’s

when selecting a monitoring instrument, (2) how laboratory

analysis can be performed to generate data to determine an RF for

a given compound, and (3) when laboratory analysis is

recommended.

Response factors contained in appendix D can be used as a

guide for selecting an appropriate monitoring device. If at the

applicable leak definition, the RF of an instrument is greater

than 10, that instrument does not meet Reference Method 21

requirements unless a substitute reference gas is used to

calibrate the instrument. For example, at a concentration of

10,000 ppmv, it can be seen that when screening equipment in a

process unit that contains cumene, an FID can be used (RF = 1.92

at an actual concentration of 10,000 ppmv), while the catalytic

oxidation detector cannot (RF = 12.49). Similarly, at a

3-7
concentration of 10,000 ppmv, neither of these devices respond to

carbon tetrachloride and, therefore, cannot be used unless

calibrated with a substitute VOC such that an RF of under 10 can

be calculated for this compound.

Response factors can be determined by laboratory analysis

using the following method. First, the analyzer is calibrated

using the reference gas. Then, for each organic species that is

to be measured, a known standard in air is obtained or prepared.

The concentration of the organic species should be at

approximately the leak definition value. This mixture is then

injected into the analyzer and the observed meter reading is

recorded. The analyzer is then "zeroed" by injecting zero air

until a stable reading is obtained. The procedure is repeated by

alternating between the mixture and zero air until a total of

three measurements are obtained. An RF is calculated for each

repetition and then averaged over the three measurements. This

procedure can be repeated at several different concentration

values. The data can then be used to generate a curve that

relates RF to screening value. (See appendix A.)

The most accurate method for estimating RF’s is to perform

laboratory analysis. This is particularly true because RF’s

vary, not just for the detector type, but also for each

individual instrument. However, in some cases, time and resource

constraints may require the use of published RF data.

Nevertheless, a limitation of the published data is that it is

typically specific to a pure compound for a single actual

concentration value, detector type, and calibration gas.

Additionally, although an RF for mixtures can be calculated as

described in section 2.4.2 (i.e., if an RF is known for each

individual compound), the most accurate RF for a mixture is

calculated by preparing known standards of air for the mixture

and injecting the standard into the analyzer as described

earlier.

3-8
3.2.2.2 Response Time. The response time of an analyzer is

defined as the time interval from a step change in VOC

concentration at the input of a sampling system, to the time at

which the corresponding concentration value is reached as

displayed on the analyzer readout meter. Response time is

determined by introducing zero air into the instrument sample

probe. When the meter reading has stabilized, the specified

calibration gas is injected. The response time is measured as

the time lapsed between switching to the calibration gas and the

time when 90 percent of the final stable reading is obtained.

This test is performed three times and the response time is

calculated as the average of the three tests. The response time

must be equal to or less than 30 seconds for the analyzer to be

acceptable for screening purposes.

The response time test is required before placing an analyzer

in service. The response time must be determined for the

analyzer configuration that will be used during testing. If a

modification to the sample pumping system or flow configuration

is made that would change the response time (e.g., change in

analyzer probe or probe filter, or the instrument pump), a new

test is required before the screening survey is conducted.

3.2.2.3 Calibration Precision. Calibration precision is the

degree of agreement between measurements of the same known value.

To ensure that the readings obtained are repeatable, a

calibration precision test must be completed before placing the

analyzer in service, and at 3-month intervals, or at the next

use, whichever is later. The calibration precision must be equal

to or less than 10 percent of the calibration gas value.

To perform the calibration precision test, three measurements

are required for each non-zero concentration. Measurements are

made by first introducing zero gas and adjusting the analyzer to

zero. The specified calibration gas (reference) is then

introduced and the meter reading is recorded. This procedure

must be performed three times. The average algebraic difference

between the meter readings and the known value of the calibration

gas is then computed. This average difference is then divided by

3-9
the known calibration value and multiplied by 100 to express the

resulting calibration precision as percent. The calibration

precision of the analyzer must be equal to or less than

10 percent of the calibration gas value.

3.2.2.4 Safety. Portable instruments to detect VOC

emissions from equipment leak sources are required to be used in

potentially hazardous locations such as petroleum refineries and

bulk gasoline terminals. The National Electrical Code requires

that instruments to be used in hazardous locations be certified

to be explosion-proof, intrinsically safe, or purged.

Hazardous locations are divided into three classes: Class I,

Class II, and Class III. Each class is divided into two

divisions (division 1 or 2) according to the probability that a

hazardous atmosphere will be present and also into seven groups,

depending on the type of hazardous material exposure: Groups A

through D are flammable gases or vapors, and groups E, F, and G

apply to combustible or conductive gases. Class I, division 1,

groups A, B, C, and D locations are those in which hazardous

concentrations of flammable gases or vapors may exist under

normal operating conditions. Class I, division 2, groups A, B,

C, and D locations are those in which hazardous concentrations of

flammable gases may exist only under unlikely conditions of

operation.

Any instrument considered for use in potentially hazardous

environments must be classified as intrinsically safe for

Class I, division 1 and class II, division 1 conditions at a

minimum. The instrument must not be operated with any safety

device, such as an exhaust flame arrestor, removed.

Table 3-2 lists several portable VOC detection instruments.

table 3-2 includes manufacturer, model number, pollutants

detected, principle of operation, and range. Note that

additional instruments, not listed here, may be available.

3.2.3 Use of Monitoring Devices That Do Not Meet EPA Reference

Method 21 Requirements

In some cases, a monitoring device may not be available that

meets all of the performance specifications of the EPA Reference

3-10
TABLE 3-2. PORTABLE VOC DETECTION INSTRUMENTS

Manufacturer Model no.

Pollutant(s)

detected

Principle of

operation

Bacharach Instrument Co.,Santa Clara, California

LTLV Sniffer

Combustible gasesCombustible gases

Catalytic combustionCatalytic combustion

0-100% LELa0-1,000 and 

Foxboro,S. Norwalk, Connecticut

OVA-128OVA-108Miran IBX

Most organic compoundsMost organic compoundsCompounds that absorbinfrared radiation

FID/GCFID/GCNDIR

0-1,0000-10,000Compound sp

Health Consultants Detecto -

PAK III

Most organic compounds FID/GC 0-10,000

HNU Systems, Inc.Newton Upper Falls,Massachusetts

HW-101 Chlorinated hydrocarbons,

aromatics, aldehydes,ketones, any substancethat UV light ionizes

Photoionization 0-20, 0-200

Mine Safety Appliances Co.,Pittsburgh, Pennsylvania

40 Combustible gases Catalytic combustion 0-10% and

0-100% LELa

Survey and Analysis, Inc.,Northboro, Massachusetts

On Mark Model 5 Combustible gases Thermal conductivity 0-5 and 0-1

aLEL = Lower explosive limit.

3-11
Method 21. For example, there are several cases (e.g., phosgene)

where the RF at 10,000 ppmv is greater than 10. An instrument

may meet all other requirements, but fail as a Reference

Method 21 instrument because it cannot meet the RF requirement.

If an instrument fails to meet Reference Method 21 requirements,

it can still be used for the purpose of estimating emissions if

its reliability can be documented.

Two primary steps must be taken to document the reliability

of an analyzer that fails to meet the Reference Method 21

requirements. First, a laboratory program must be undertaken to

demonstrate the response of the monitoring instrument to the

compounds being measured; that is, an instrument response curve

must be developed for the entire screening value range and

documented so that screening values taken in the field can be

adjusted to actual concentrations if necessary. Second, the

testing program must be sufficiently well-documented to

demonstrate how the instrument will be used when screening

equipment. For example, if the response time of the candidate

instrument exceeds the Reference Method 21 performance

specification, the test plan should reflect added screening time

at each potential leak point. Once this laboratory demonstration

has been completed and the screening value correction curve has

been established, the instrument may be used in a screening

program.

3.3 THE SCREENING PROGRAM

The goal of the screening program is to measure VOC

concentrations at seals, shafts, and other potential leak points.

All equipment to be included in the screening survey needs to be

identified before the screening program starts. A list of

equipment types that are potential sources of fugitive emissions

is provided in table 3-3.

3.3.1 Identification of Equipment to be Screened

The first step in the screening survey is to precisely define

the process unit boundaries. This is usually straightforward,

but occasionally multiple units may be built on the same pad and

share some common facilities. A process unit can be defined as

3-12
TABLE 3-3. EQUIPMENT LEAK EMISSION SOURCES

Equipment types

Agitator seals

Compressor seals

Connectors

Diaphrams

Drains

Dump lever arms

Flanges

Hatches

Instruments

Loading arms

Meters

Open-ended lines

Polished rods

Pressure relief devices

Pump seals

Stuffing boxes

Valves

Vents

Service

Gas/vapor

Light liquid

Heavy liquid

3-13
the smallest set of process equipment that can operate

independently and includes all operations necessary to achieve

its process objective. The exact basis for the unit definition

should be documented. A plot plan of the unit should be obtained

and marked with the appropriate boundaries.

The next step is to obtain a simplified flow diagram of the

process and note the process streams. The actual screening and

data collection can be done efficiently by systematically

following each stream. For example, a logical starting point

would be where one of the feed lines enters the process boundary.

The screening team would follow that line, screening all sources,

until the line terminates at the connectors of a reactor or

separation step. This approach offers the advantage of screening

groups of equipment with roughly the same composition of material

in the line. Screening would then continue on the outlet side of

the reactor or separation equipment. Minor loops, such as a

bypass around a control valve, pump, or heat exchanger, should be

screened on the initial pass. Larger loops of process equipment,

such as parallel passes and processing alternatives, are more

effectively treated as separate streams.

Each source should be uniquely identified to indicate that it

has been screened. For example, sources can be tagged. Tags can

consist of any form of weatherproof and readily visible

identification. Alternatively, a process unit can be considered

appropriately tagged if the unit has a system of identifying

markings with an associated diagram allowing easy location of

marked sources. Once all the equipment along the major streams

has been screened, the unit should be divided into a grid to

search for fittings missed on the initial survey. Consistent

with equipment leaks standards, equipment that is unsafe to

monitor or very difficult to access does not need to be included

in the survey. Documentation must be provided, however, to

substantiate the unsafe or confined nature of such equipment.

3-14
3.3.2 Procedure for Screening

Once the equipment to be screened has been identified, the

procedures outlined in the EPA Reference Method 21 to screen each

equipment type are followed.1 The probe inlet is placed at the

surface of the potential leak interface where leakage could

occur. (The potential leak interface is the boundary between the

process fluid and the atmosphere.) For equipment with no moving

parts at the leak interface, the probe should be placed directly

on the leak interface; for equipment with moving parts (e.g.,

pumps, compressors, and agitators), the probe should be placed

approximately 1 centimeter off from the leak interface. Care

must be taken to ensure that the probe is held perpendicular, not

tangential, to the leak potential interface; otherwise,

inaccurate readings will result. The probe must then be moved

along the interface periphery while observing the instrument

readout. If an increased meter reading is observed, slowly move

the probe along the interface where concentrations register until

the maximum meter reading is obtained. The probe inlet should be

left at this maximum reading location for approximately two times

the instrument response time. The maximum reading is recorded as

the screening value.

The instrument measurement may exceed the scale of the

instrument. This is referred to as a "pegged" readout. For

example, for several instruments, the highest readout on the

scale is 10,000 ppmv. For the purposes of generating an

emissions estimate, a dilution probe should be employed to

measure concentrations greater than the instrument’s normal range

unless average emission factors for greater than or equal to the

"pegged" readout are applied. It is important to note that

extending the measurement range necessitates the calibration of

the instrument to the higher concentrations.

Care should be taken to avoid fouling the probe with grease,

dust, or liquids. A short piece of Teflon® tubing can be used as

a probe tip extender and then can be snipped off as the tip

fouls. In areas with a noticeable particulate loading, this

tubing can be packed loosely with untreated fiberglass, which

3-15
acts as a filter. (Note that the instrument must also be

calibrated with this filter in place.) If a surface to be

screened is obviously dirty, hold the probe tip just over the

surface to avoid scooping up contaminants. Some fouling is

unavoidable, so it is recommended that the probe tip filter be

cleaned at least daily and any other filters on a weekly basis.

Normally, these filters can be cleaned by just tapping them

lightly on a table top, but if the deposits are wet and caked on,

they should be washed with an aqueous solution of soap and

alcohol. This solution also can be used to wash the probe and

transfer line periodically. Care should be taken to blow the

equipment dry before reuse.

This general procedure can be used to screen equipment such

as valves, connectors and flanges, pumps and compressors,

open-ended lines, and other potential sources of VOC leakage,

such as pressure relief devices, loading arms, stuffing boxes,

instruments, vents, dump lever arms, drains, diaphrams, hatches,

notes, or polished rods. The following sections describe the

location on each type of equipment where screening efforts should

be concentrated.

3.3.2.1 Valves. For valves, the most common source of leaks

is at the seal between the stem and housing. To screen this

source, the probe opening is placed where the stem exits the

packing gland and is moved around the stem circumference. The

maximum reading is recorded as the screening valve. Also, the

probe opening is placed at the packing gland take-up connector

seat, and the probe is moved along the periphery. In addition,

valve housings of multipart assemblies should be screened at the

surface of all points where leaks could occur. Figures 3-1

through 3-5 illustrate screening points for several different

types of valves.

3.3.2.2 Connectors and Flanges. For connectors, the probe

opening is placed at the outer edge of the connector - gasket

interface and the circumference of the connector is sampled. For

screwed connectors, the threaded connection interface must also

be screened. Other types of nonpermanent joints, such as

3-16
Rising Stem Type

 Nonrising Stem Type Packing Nut

Packing Gland

Packing

Disk or Wedge

Screen

Here

Stem

Packing Gland

Packing

Packing Out

Screen

Here

Disk or Wedge

3-17

Figure 3-1. Gate Valves
Manual Globe Valve

Stem

Packing

Gland

Packing

Screen

Here

Packing Nut

Screen

Here

Body

Seat

Disk

Stem

Body

Screen

Here

Packing

Globe Type Control Valve

3-18

Figure 3-2. Globe Valves

 through 
Plug

Screen Here

3-19

Figure 3-3. Lubricated Plug Valve
Ball Valve

Ball

Packing

Screen Here

Disk

Screen Here

Butterfly Valve

3-20

Figure 3-4. Ball Valve and Butterfly Valve
Diaphragm

Stem

Weir

Screen Here

Weir-Type Diaphragm Valve

Check Valves

Swing Check

Lift Check

Screen Here

Screen

Here

3-21

Figure 3-5. Weir-Type Diaphragm Valve and Check Valves
threaded connections, are sampled with a similar traverse.

3.3.2.3 Pumps, Compressors, and Agitators. Pumps,

compressors, and agitators are screened with a circumferential

traverse at the outer surface shaft and seal interface where the

shaft exits the housing. If the source is a rotating shaft, the

probe inlet is positioned within 1 centimeter of the shaft - seal

interface. If the housing configuration prevents a complete

traverse of the shaft periphery, all accessible portions must be

sampled. All other joints on the pump or compressor housing

where leakage could occur should also be sampled. Figure 3-6

illustrates screening points for two types of centrifugal pumps.

3.3.2.4 Pressure Relief Devices. The configuration of most

pressure relief devices prevents sampling at the sealing seat.

Because of their design and function, pressure relief devices

must be approached with extreme caution. These devices should

not be approached during periods of process upsets, or other

times when the device is likely to activate. Similarly, care

must be used in screening pressure relief devices to avoid

interfering with the working parts of the device (e.g., the seal

disk, the spring, etc.) For those devices equipped with an

enclosed extension, or horn, the probe inlet is placed at

approximately the center of the exhaust area to the atmosphere.

It should be noted that personnel conducting the screening should

be careful not to place hands, arms, or any parts of the body in

the horn. Figure 3-7 illustrates the screening points for a

spring-loaded relief valve.

3.3.2.5 Open-Ended Lines. Fugitive leaks from open-ended

lines are emitted through a regularly shaped opening. If that

opening is very small (as in sampling lines of less than 1 inch

in diameter), a single reading in the center is sufficient. For

larger openings it is necessary to traverse the perimeter of the

opening. The concentration at the center must also be read.

3-22
3-23

Figure 3-6. Centrifugal Pumps

Horizontal Centrifugal Pump

Vertical Centrifugal Pump

Screen Here

Stationary Casing

Screen Here

Moving Shaft
3-24

Figure 3-7. Spring-Loaded Relief Valve

Screen Here

Horn

Tension Adjustment

Thimble

Spring

Disk

Nozzle

Alternate Screening

Area if Horn

Inaccessible

To Process
3.3.3 Data Handling

To ensure that data quality is maintained, it is recommended

that data be recorded on prepared data sheets. The data

collected should include the following:

1. Monitoring instrument type and model number.

2. Operator’s name.

3. Date.

4. Component identification number (ID number). (If

permanent ID’s are not in place, assign ID’s as each

source is screened.)

5. Component type (i.e., valve, connector, open-ended line,

etc.)

6. Location/stream. (Provide brief description of where

the screened component is located and the composition of

material in the equipment.)

7. Service (i.e., gas, light liquid, or heavy liquid).

8. Number of hours per year the component is in service.

9. Screening value (ppmv).

10. Background concentration (ppmv).

11. Comments. If any explanation is required, it should be

noted in a "comments" section.

In some cases, it may be necessary or desirable to adjust the

screening values for RF. In these cases, the data sheet should

be designed to accommodate extra columns for RF and corrected

screening values. Table 3-4 provides an example data sheet that

may be used to log measurements taken during a screening program.

3-25
TABLE 3-4. EXAMPLE FIELD SHEETS FOR EQUIPMENT SCREENING DATA

Detector model no.Operator nameDate

Component

ID

Component

Type

Location/

Stream Service

Operating

hrs/yr

Screening

value

(ppmv)

Backgrou

(ppmv) 

3-26
3.4 REFERENCES

1. Code of Federal Regulations, Title 40, Part 60, Appendix A.

Reference Method 21, Determination of Volatile Organic

Compound Leaks. Washington, DC. U.S. Government Printing

Office. Revised June 22, 1990.

3-27
4.0 MASS EMISSION SAMPLING

4.1 INTRODUCTION

This chapter describes the procedures for "bagging"

equipment to measure mass emissions of organic compounds. An

equipment component is bagged by enclosing the component to

collect leaking vapors. Measured emission rates from bagged

equipment coupled with screening values can be used to develop

unit-specific screening value/mass emission rate correlation

equations. Unit-specific correlations can provide precise

estimates of mass emissions from equipment leaks at the process

unit. However, it is recommended that unit-specific correlations

are only developed in cases where the existing EPA correlations

do not give reasonable mass emission estimates for the process

unit. The focus of the chapter is on bagging equipment

containing organic compounds, but similar procedures can be

applied to bag equipment containing inorganic compounds as long

as there are comparable analytical techniques for measuring the

concentration of the inorganic compound.

This chapter is divided into four sections. In section 4.2,

the methods for bagging equipment are discussed. Considerations

for bagging each equipment type are discussed in section 4.3. In

section 4.4, techniques used in the laboratory analysis of bagged

samples are discussed. Section 4.4 also includes a description

of a rigorous calibration procedure for the portable monitoring

device that must be followed. Finally, in section 4.5, quality

assurance and quality control (QA/QC) guidelines are provided.

4-1
4.2 SAMPLING METHODS

The emission rate from an equipment component is measured by

bagging the component--that is, isolating the component from

ambient air to collect any leaking compound(s). A tent

(i.e., bag) made of material impermeable to the compound(s) of

interest is constructed around the leak interface of the piece of

equipment. A known rate of carrier gas is induced through the

bag and a sample of the gas from the bag is collected and

analyzed to determine the concentration (in parts per million by

volume [ppmv]) of leaking material. The concentration is

measured using laboratory instrumentation and procedures. Mass

emissions are calculated based on the measured concentration and

the flow rate of carrier gas through the bag.

In some cases, it may be necessary to collect liquid leaking

from a bagged equipment piece. Liquid can either be dripping

from the equipment piece prior to bagging, and/or be formed as

condensate within the bag. If liquid accumulates in the bag,

then the bag should be configured so that there is a low point to

collect the liquid. The time in which the liquid accumulates

should be recorded. The accumulated liquid should then be taken

to the laboratory and transferred to a graduated cylinder to

measure the volume of organic material. Based on the volume of

organic material in the cylinder (with the volume of water or

nonorganic material subtracted out), the density of the organic

material, and the time in which the liquid accumulated, the

organic liquid leak rate can be calculated. Note that the

density can be assumed to be equivalent to the density of organic

material in the equipment piece, or, if sufficient volume is

collected, can be measured using a hydrometer. It should be

noted that in some cases condensate may form a light coating on

the inside surface of the bag, but will not accumulate. In these

cases, it can be assumed that an equilibrium between condensation

and evaporation has been reached and that the vapor emissions are

equivalent to total emissions from the source.

When bagging an equipment piece, the enclosure should be

kept as small as practical. This has several beneficial effects:

4-2
The time required to reach equilibrium is kept to a

minimum;

The time required to construct the enclosure is

minimized;

A more effective seal results from the reduced seal

area; and

Condensation of heavy organic compounds inside the

enclosure is minimized or prevented due to reduced

residence time and decreased surface area available for

heat transfer.

Two methods are generally employed in sampling source

enclosures: the vacuum method and the blow-through method. Both

methods involve enclosing individual equipment pieces with a bag

and setting up a sampling train to collect two samples of leaking

vapors to be taken to the laboratory for analysis. Both methods

require that a screening value be obtained from the equipment

piece prior to and after the equipment piece is enclosed. The

methods differ in the ways in which the carrier gas is conveyed

through the bag. In the vacuum method, a vacuum pump is used to

pull air through the bag. In the blow-through method, a carrier

gas such as nitrogen (or other inert gas) is blown into the bag.

In general, the blow-through method has advantages over the

vacuum method. These advantages are as follows.

(1) The blow-through method is more conducive to better

mixing in the bag.

(2) The blow-through method minimizes ambient air in the bag

and thus reduces potential error associated with

background organic compound concentrations. (For this

reason the blow-through method is especially preferable

when measuring the leak rate from components with zero

or very low screening values.)

(3) The blow-through method minimizes oxygen concentration

in the bag (assuming air is not used as the carrier gas)

and the risk of creating an explosive environment.

(4) In general, less equipment is required to set up the

blow-through method sampling train.

However, the blow-through method does require a carrier gas

source, and preferably the carrier gas should be inert and free

4-3
of any organic compounds and moisture. The vacuum method does

not require a special carrier gas.

Details of the sampling train of each of these bagging

methods are discussed in sections 4.2.1 and 4.2.2, respectively.

These sections also contain summaries of the steps of the

sampling procedure for each method. For both methods, the

approach described above for collecting and measuring liquid leak

rates can be utilized. In addition to the sampling descriptions

presented in the following sections, the quality control and

assurance guidelines presented in section 4.5 must also be

followed when bagging equipment.

4.2.1 Vacuum Method

The sampling train used in the vacuum method is depicted in

figure 4-1. The train can be mounted on a portable cart, which

can be moved around the process unit from component to component.

The major equipment items in the sampling train are the vacuum

pump used to draw air through the system, and the dry gas meter

used to measure the flow rate of gas through the train. In

previous studies that the EPA conducted, a 4.8-cubic feet per

minute Teflon® ring piston-type vacuum pump equipped with a

3/4-horsepower, air-driven motor was used. Other equipment that

may be used in the train includes valves, copper and stainless

steel tubing, Teflon® tubing and tape, thermometer,

pressure-reading device, liquid collection device, and air-driven

diaphragm sampling pumps. It also may be necessary to use

desiccant preceding the dry gas meter to remove any moisture.

The bag is connected by means of a bulkhead fitting and

Teflon® tubing to the sampling train. A separate line is

connected from the bag to a pressure-reading device to allow

continuous monitoring of the pressure inside the bag. If a

significant vacuum exists inside the bag when air is being pulled

through, a hole is made in the opposite side of the bag from the

outlet to the sampling train. This allows air to enter the bag

more easily and, thus, reduces the vacuum in the enclosure.

However, it is important to maintain a vacuum in the bag, since

VOC could be lost through the hole if the bag became pressurized.

4-4
This line should

be as short

as possible

Tent

Leaking

Valve

Cold Trap in Ice Bath

(Optional)

Dry Gas

Meter

Trap

Hg Manometer

Control

Valve

Filter

Small

Diaphragm

Pump Two-Way Valve

Sample Bag

Vacuum

Pump

Pressure

Reading

Device

4-5

Figure 4-1. Sampling train for bagging a source using the vacuum

method.
In practice, it has been found that only a very slight vacuum

(0.1 inches of water) is present in the bag during most of the

sampling, even in the absence of a hole through the bag wall.

Sufficient air enters around the seals to prevent the development

of a significant vacuum in the bag. A small diaphragm sampling

pump can be used to collect two samples into sample bags or

canisters, which are then transported to the laboratory for

analysis.

The diaphragm pump can also be used to collect a background

sample of the ambient air near the bagged component. The

concentration in the background bag is subtracted from the

average concentration in the sample bags when calculating the

leak rate. Often this correction is insignificant (particularly

for components with high leak rates or in cases where there is no

detectable volatile organic compound (VOC) concentration measured

by the portable monitoring device), and collection of a

background bag is optional. However, in some cases collection of

a background bag is important so that emission rates are not

biased high.

Any liquid that accumulates in the bag should be collected

using the approach described in section 4.2. Note that if there

is a concern that condensation will occur in equipment downstream

from the bag outlet, a cold trap can be placed as close to the

bag outlet as possible to remove water or heavy organic compounds

that may condense downstream. Any organic condensate that

collects in the cold trap must be measured to calculate the total

leak rate.

The flow rate through the system can be varied by throttling

the flow with a control valve immediately upstream of the vacuum

pump. Typical flow rates are approximately 60 liters per minute

( /min) or less. A good flow rate to use is one in which a

balance can be found between reaching equilibrium conditions and

having a high enough concentration of organic compounds in the

bag outlet to accurately measure the concentration in the

laboratory. As the flow rate is decreased, the concentration of

organic compounds increases in the gas flowing through the

4-6
sampling system. The flow rate should be adjusted to avoid any

operations with an explosive mixture of organic compounds in air.

It may also be possible to increase the flow rate in order to

minimize liquid condensation in the bag.

The flow rate should be set to a constant rate and kept at

that rate long enough for the system to reach equilibrium. To

determine if equilibrium conditions have been reached, a portable

monitoring device can be used to indicate if the outlet

concentration has stabilized.

It is not recommended that the vacuum method be used to

measure the leak rate from equipment that have low screening

values (approximately 10 ppmv or less), because considerable

error can be introduced due to the background organic

concentration in the ambient air that is pulled through the bag.

In summary, the vacuum sampling procedure consists of the

following steps.

(1) Determine the composition of material in the designated

equipment component, and the operating conditions of the

component.

(2) Obtain and record a screening value with the portable

monitoring instrument.

(3) Cut a bag from appropriate material (see section 4.3)

that will easily fit over the equipment component.

(4) Connect the bag to the sampling train.

(5) If a cold trap is used, immerse the trap in an ice bath.

(6) Note the initial reading of the dry gas meter.

(7) Start the vacuum pump and a stopwatch simultaneously.

Make sure a vacuum exists within the bag.

(8) Record the temperature and pressure at the dry gas

meter.

(9) Observe the VOC concentration at the vacuum pump exhaust

with the monitoring instrument. Make sure concentration

stays below the lower explosive limit.

(10) Record the temperature, pressure, dry gas meter

reading, outlet VOC concentration and elapsed time

every 2 to 5 minutes (min).

4-7
(11) Collect 2 gas samples from the discharge of the

diaphragm sampling pump when the outlet concentration

stabilizes (i.e., the system is at equilibrium).

(12) Collect a background bag (optional).

(13) Collect any liquid that accumulated in the bag as

well as in the cold trap (if used) in a sealed

container.

(14) Take a final set of readings and stop the vacuum

pump.

(15) Transport all samples to the laboratory, along with

the data sheet.

(16) Remove the bag.

(17) Rescreen the source with the portable monitoring

instrument and record.

Based on the data collected in the steps described above, mass

emissions are calculated using the equation presented in

table 4-1.

4.2.2 Blow-Through Method

The sampling train for the blow-through method is presented

in figure 4-2. The temperature and oxygen concentrations are

measured inside the bag with a thermocouple (or thermometer) and

an oxygen/combustible gas monitor. The carrier gas is metered

into the bag through one or two tubes (two tubes provide for

better mixing) at a steady rate throughout the sampling period.

The flow rate of the carrier gas is monitored in a gas rotameter

calibrated to the gas. Typical flow rates are approximately

60 /min or less. It is preferable to use an inert gas such as

nitrogen for the blow-through method so as to minimize the risk

of creating an explosive environment inside the bag. Also, the

carrier gas should be free of any organic compounds and moisture.

The pressure in the bag should never exceed 1 pound per square

inch gauge (psig).

The flow rate through the bag can be varied by adjusting the

carrier gas regulator. As mentioned in section 4.2.1, a good

flow rate to use is one in which a balance can be found between

reaching equilibrium conditions and having a high enough

4-8
TABLE 4-1. CALCULATION PROCEDURES FOR LEAK RATE WHEN USING THE

VACUUM METHOD

Leak Rate = 9.63 x 10-10 (Q)(MW)(GC)(P) ( + ρ)(VL)

(kg/hr) T + 273.15 16.67(t)

where:

9.63 x 10-10 = A conversion factor using the gas constant:

°K × 106 × kg-mol × min

;

× hour × mmHg

Q = Flow rate out of bag ( /min);

MWa = Molecular weight of organic compound(s) in

the sample bagc or alternatively in the

process stream contained within the equipment

piece being bagged (kg/kg-mol);

GCb = Sample bag organic compound concentration

(ppmv) minus background bag organic compound

concentrationc (ppmv);

P = Absolute pressure at the dry gas meter

(mmHg);

T = Temperature at the dry gas meter (°C);

ρ = Density of organic liquid collected (g/m );

VL = Volume of liquid collected (m );

16.67 = A conversion factor to adjust term to units

of kilograms per hour (g × hr)/(kg × min)

t = Time in which liquid is collected (min); and

aFor mixtures calculate MW as:

n n

= ∑ MWi Xi / ∑ Xi

i=1 i=1

where:

MWi = Molecular weight of organic compound i;

Xi = Mole fraction of organic compound i; and

n = Number of organic compounds in mixture. bFor mixtures, the value of GC is the total concentration of all

the organic compounds in the mixture.

cCollection of a background bag is optional. If a background bag

is not collected, assume the background concentration is zero.

4-9
Carrier

Gas

Source

Pressure

Regulator

Dessicant

Activated

Charcoal

Rotameter

1/4" Insulated

Teflon Tubing

Valve Stem

Tape or Adjustable Metal Band

Sample Port for Collecting Data on

- Temperature

- Hydrocarbon Concentration

- Oxygen Concentration

Foil or Tape or Compressed Foil

Mylar

Enclosure

(if needed)

(if needed)

R

R

4-10

Figure 4-2. Equipment Required for the Blow-Through

Sampling Technique
concentration of organic compounds in the bag outlet to

accurately measure the concentration in the laboratory.

Adjustments to the flow rate may also help minimize liquid

condensation in the bag. Any liquid that does accumulate in the

bag should be collected using the approach described in

section 4.2.

The carrier gas flow rate should be set to a constant rate

and kept at that rate long enough for the system to reach

equilibrium. In addition to the carrier gas flow through the

bag, some ambient air may enter the bag if it is not airtight.

The oxygen measurements are used to determine the flow of ambient

air through the bag. The oxygen measurements are also an

indication of the quality of the bagging procedure (the lower the

oxygen concentration the better). Once oxygen concentration

falls below 5 percent, the portable monitoring instrument is used

to check organic compound concentrations at several locations

within the bag to ensure that the bag contents are at steady

state.

Once the bag contents are at steady state, two gas samples

are drawn out of the bag for laboratory analysis using a portable

sampling pump. It may also be necessary to collect a background

bag sample, particularly if the source had screened at zero and

if there is still a detectable level of oxygen in the bag.

However, collection of a background bag is optional.

In summary, the blow-through method consists of the

following steps, which assume nitrogen is used as the carrier

gas.

(1) Determine the composition of the material in the

designated equipment component, and the operating

conditions of the component.

(2) Screen the component using the portable monitoring

instrument.

(3) Cut a bag that will easily fit over the equipment

component.

4-11
(4) Connect tubing from the nearest nitrogen source to a

rotameter stand.

(5) Run tubing from the rotameter outlet to a "Y" that

splits the nitrogen flow into two pieces of tubing and

insert the tubes into openings located on either side of

the bag.

(6) Turn on the nitrogen flow and regulate it at the

rotameter to a constant rate and record the time.

(7) After the nitrogen is flowing, wrap aluminum foil around

those parts of the component where air could enter the

bag-enclosed volume.

(8) Use duct tape, wire, and/or rope to secure the bag to

the component.

(9) Put a third hole in the bag roughly equidistant from the

two carrier gas-fed holes.

(10) Measure the oxygen concentration in the bag by

inserting the lead from an oxygen meter into the

third hole. Adjust the bag (i.e., modify the seals

at potential leak points) until the oxygen

concentration is less than 5 percent.

(11) Measure the temperature in the bag.

(12) Check the organic compound concentration at several

points in the bag with the portable monitoring

instrument to ensure that carrier gas and VOC are

well mixed throughout the bag.

(13) Collect samples in sample bags or canisters by

drawing a sample out of the bag with a portable

sampling pump.

(14) Collect a background bag (optional).

(15) Remove the bag and collect any liquid that

accumulated in the bag in a sealed container. Note

the time over which the liquid accumulated.

(16) Rescreen the source.

Table 4-2 gives equations used to calculate mass emission rates

when using the blow-through method. An adjustment is provided

for the leak rate equation in table 4-2 to account for the total

flow through the bag. This adjustment is recommended and

represents an improvement over previous versions

4-12
TABLE 4-2. CALCULATION PROCEDURES FOR LEAK RATE

WHEN USING THE BLOW-THROUGH METHOD

where:

Leak Rate

(kg/hr)













1.219 x 10 5 (Q) (MW) (GC)

T 273.15

(ρ) (VL)

16.67 (t)

x 











106ppmv

106ppmv GC

1.219 x 10-5 = A conversion factor taking into account the gas

constant and assuming a pressure in the tent of

1 atmosphere:

oK × 106 × kg-mol

;

m3

Q = flow rate out of tent (m3/hr);

= N2 Flow Rate ( /min) × [0.06 (m3/min)]

1 - [Tent Oxygen Conc. (volume %)/21] ( /hr)

MWa = Molecular weight of organic compounds in the

sample bag or alternatively in the process

stream contained within the equipment piece

being bagged (kg/kg-mol);

GCb = Sample bag organic compound concentration

(ppmv), corrected for background bag organic

compound concentration (ppmv);c

T = Temperature in tent (oC);

ρ = Density of organic liquid collected (g/m );

VL = Volume of liquid collected (m );

16.67 = A conversion factor to adjust term to units of

Kilograms per hour (g × hr)/(kg × min); and

t = Time in which liquid is collected (min).

aFor mixtures calculate MW as:

n n

= ∑ MWi Xi / ∑ Xi

i=1 i=1

where:

MWi = Molecular weight of organic compound i;

4-13
TABLE 4-2. CALCULATION PROCEDURES FOR LEAK RATE

WHEN USING THE BLOW-THROUGH METHOD

(Continued)

Xi = Mole fraction of organic compound i; and

n = Number of organic compounds in mixture.

bFor mixtures, the value of GC is the total concentration of all

the organic compounds in the mixture.

cCollection of a background bag is optional. If a background bag

is not collected, assume the background concentration is zero.

To correct for background concentration, use the following

equation:

where:

GC

(ppmv) SB TENT

21

x BG

SB = Sample bag concentration (ppmv);

TENT = Tent oxygen concentration (volume %); and

BG = Background bag concentration (ppmv)

4-14
of this document for quantifying mass emissions from the blow

through method.

4.3 SOURCE ENCLOSURE

In this section, choosing a bagging material and the

approach for bagging specific equipment types are discussed. An

important criteria when choosing the bagging material is that it

is impermeable to the specific compounds being emitted from the

equipment piece. This criteria is also applicable for sample gas

bags that are used to transport samples to the laboratory. A bag

stability test over time similar to the Flexible Bag Procedure

described in section 5.3.2 of the EPA method 18 is one way to

check the suitability of a bagging material.1 After a bag has

been used, it must be purged. Bags containing residual organic

compounds that cannot be purged should be discarded. Mylar®,

Tedlar®, Teflon®, aluminum foil, or aluminized Mylar® are

recommended potential bagging materials. The thickness of the

bagging material can range from 1.5 to 15 millimeters (mm),

depending on the bagging configuration needed for the type of

equipment being bagged, and the bagging material. Bag

construction for individual sources is discussed in

sections 4.3.1 through 4.3.5. For convenience, Mylar® will be

used as an example of bagging material in the following

discussions.

4.3.1 Valves

When a valve is bagged, only the leak points on the valve

should be enclosed. Do not enclose surrounding flanges. The

most important property of the valve that affects the type of

enclosure selected for use is the metal skin temperature where

the bag will be sealed. At skin temperatures of approximately

200 oC or less, the valve stem and/or stem support can be wrapped

with 1.5- to 2.0-mm Mylar® and sealed with duct tape at each end

and at the seam. The Mylar® bag must be constructed to enclose

the valve stem seal and the packing gland seal.

When skin temperatures are in excess of 200 oC, a different

method of bagging the valve should be utilized. Metal bands,

wires, or foil can be wrapped around all hot points that would be

4-15
in contact with the Mylar® bag material. Seals are then made

against the insulation using duct tape or adjustable metal bands

of stainless steel. At extremely high temperatures, metal foil

can be used as the bagging material and metal bands used to form

seals. At points where the shape of the equipment prevent a

satisfactory seal with metal bands, the foil can be crimped to

make a seal.

4.3.2 Pumps and Agitators

As with valves, a property of concern when preparing to

sample a pump or agitator is the metal skin temperature at areas

or points that are in contact with the bag material. At skin

temperatures below 200 oC, Mylar® plastic and duct tape are

satisfactory materials for constructing a bag around a pump or

agitator seal. If the temperature is too high or the potential

points of contact are too numerous to insulate, an enclosure made

of aluminum foil can be constructed. This enclosure is sealed

around the pump and bearing housing using silicone fabric

insulting tape, adjustable metal bands, or wire.

The configuration of the bag will depend upon the type of

pump. Most centrifugal pumps have a housing or support that

connects the pump drive (or bearing housing) to the pump itself.

The support normally encloses about one-half of the area between

the pump and drive motor, leaving open areas on the sides. The

pump can be bagged by cutting panels to fit these open areas.

These panels can be made using thicker bagging material such as

14-mm Mylar®. In cases where supports are absent or quite

narrow, a cylindrical enclosure around the seal can be made so

that it extends from the pump housing to the motor or bearing

support. As with the panels, this enclosure should be made with

thicker bagging material to provide strength and rigidity.

Reciprocating pumps can present a somewhat more difficult

bagging problem. If supports are present, the same type of

two-panel Mylar® bag can be constructed as that for centrifugal

pumps. In many instances, however, sufficiently large supports

are not provided, or the distance between pump and driver is

relatively long. In these cases, a cylindrical enclosure as

4-16
discussed above can be constructed. If it is impractical to

extend the enclosure all the way from the pump seal to the pump

driver, a seal can be made around the reciprocating shaft. This

can usually be best completed by using heavy aluminum foil and

crimping it to fit closely around the shaft. The foil is

attached to the Mylar® plastic of the enclosure and sealed with

the duct tape.

In cases where liquid is leaking from a pump, the outlet

from the bag to the sampling train should be placed at the top of

the bag and as far away from spraying leaks as practical. A low

point should be formed in the bag to collect the liquid so that

the volume of the liquid can be measured and converted to a mass

rate.

4.3.3 Compressors

In general, the same types of bags that are suitable for

pumps can be directly applied to compressors. However, in some

cases, compressor seals are enclosed and vented to the atmosphere

at a high-point vent. If the seals are vented to a high-point

vent, this vent line can be sampled. A Mylar® bag can be

constructed and sealed around the outlet of the vent and

connected to the sampling train. If the high-point vents are

inaccessible, the vent lines from the compressor seal enclosures

can be disconnected at some convenient point between the

compressor and the normal vent exit. Sampling is then conducted

at this intermediate point. In other cases, enclosed compressor

seals are vented by means of induced draft blowers or fans. In

these cases, if the air flow rate is know or can be determined,

the outlet from the blower/fan can be sampled to determine the

emission rate.

4.3.4 Connectors

In most cases, the physical configurations of connectors

lend themselves well to the determination of leak rates. The

same technique can be used for a connector whether it is a

flanged or a threaded fitting. To bag a connector with a skin

temperature below 200 oC, a narrow section of Mylar® film is

constructed to span the distance between the two flange faces or

4-17
the threaded fitting of the leaking source. The Mylar® is

attached and sealed with duct tape. When testing connectors with

skin temperatures above 200 oC, the outside perimeter of both

sides of the connector are wrapped with heat-resistant insulating

tape. Then, a narrow strip of aluminum foil can be used to span

the distance between the connection. This narrow strip of foil

can be sealed against the insulating tape using adjustable bands

of stainless steel.

4.3.5 Relief Valves

Relief devices in gas/vapor service generally relieve to the

atmosphere through a large-diameter pipe that is normally located

at a high point on the process unit that it serves. The "horns"

can be easily bagged by placing a Mylar® plastic bag over the

opening and sealing it to the horn with duct tape. Because may

of these devices are above grade level, accessibility to the

sampling train may be limited or prevented. It is sometimes

possible to run a long piece of tubing from the outlet connection

on the bag to the sampling train located at grade level or on a

stable platform.

As discussed previously in section 3.0, the purpose of

pressure relief devices makes them inherently dangerous to

sample, especially over a long period of time. If these

equipment are to be sampled for mass emissions, special care and

precautions should be taken to ensure the safety of the personnel

conducting the field sampling.

4.4 ANALYTICAL TECHNIQUES

The techniques used in the laboratory analysis of the bagged

samples will depend on the type of processes sampled. The

following sections describe the analytical instrumentation and

calibration, and analytical techniques for condensate. These are

guidelines and are not meant to be a detailed protocol for the

laboratory personnel. Laboratory personnel should be well-versed

in the analysis of organic compound mixtures and should design

their specific analyses to the samples being examined.

Also discussed is the calibration protocol for the portable

monitoring instrument. When bagging data are collected, it is

4-18
critical that the screening value associated with mass emission

rates is accurate. For this reason, a more rigorous calibration

of the portable monitoring instrument is required than if only

screening data are being collected.

4.4.1 Analytical Instrumentation

The use of analytical instrumentation in a laboratory is

critical to accurately estimate mass emissions. The analytical

instrument of choice depends on the type of sample being

processed. Gas chromatographs (GC’s) equipped with a flame

ionization detector or electron capture detector are commonly

used to identify individual constituents of a sample. Other

considerations besides instrument choice are the type of column

used, and the need for temperature programming to separate

individual constituents in the process stream with sufficient

resolution. For some process streams, total hydrocarbon analyses

may be satisfactory.

4.4.2 Calibration of Analytical Instruments

Gas chromatographs should be calibrated with either gas

standards generated from calibrated permeation tubes containing

individual VOC components, or bottled standards of common gases.

Standards must be in the range of the concentrations to be

measured. If cylinder calibration gas mixtures are used, they

must be analyzed and certified by the manufacturer to be within

± 2 percent accuracy, and a shelf life must be specified.

Cylinder standards beyond the shelf life must either be

reanalyzed or replaced.

Field experience indicates that certified accuracies of

± 2 percent are difficult to obtain for very low-parts per

million (ppm) calibration standards (< 10 ppm). Users of

low-parts per million calibration standards should strive to

obtain calibration standards that are as accurate as possible.

The accuracy must be documented for each concentration standard.

The results of all calibrations should be recorded on

prepared data sheets. Table 4-3 provides an example of a data

collection form for calibrating a GC. If other analytical

instruments are used to detect the organic compounds from liquid

4-19
TABLE 4-3. EXAMPLE GC CALIBRATION DATA SHEET

Plant ID

Instrument ID

Analyst Name

Date Time

Certified

Gas Conc.

(ppmv)

Instrument

Reading

(ppmv) Comments

4-20
samples, they should be calibrated according to standard

calibration procedures for the instrument.

4.4.3 Analytical Techniques for Condensate

Any condensate collected should be brought to the laboratory

sealed in the cold trap flask. This material is transferred to a

graduated cylinder to measure the volume collected. If there is

enough volume to make it feasible, the organic layer should be

separated from the aqueous layer (if present) and weighed to

determine its density. If water-miscible organic compounds are

present, both the aqueous and organic phases should be analyzed

by GC to determine the total volume of organic material.

4.4.4. Calibration Procedures for the Portable Monitoring

Instrument

To generate precise screening values, a rigorous calibration

of the portable monitoring instrument is necessary. Calibrations

must be performed at the start and end of each working day, and

the instrument reading must be within 10 percent of each of the

calibration gas concentrations. A minimum of five calibration

gas standards must be prepared including a zero gas standard, a

standard approaching the maximum readout of the screening

instrument, and three standards between these values. If the

monitoring instrument range is from 0 to 10,000 ppmv, the

following calibration gases are required:

A zero gas (0-0.2 ppm) organic in air standard;

A 9.0 ppm (8-10 ppm) organic in air standard;

A 90 ppm (80-100 ppm) organic in air standard;

A 900 ppm (800-1,000 ppm) organic in air standard; and

A 9,000 ppm (8,000-10,000 ppm) organic in air standard.

The same guidelines for the analysis and certification of the

calibration gases as described for calibrating laboratory

analytical instruments must be followed for calibrating the

portable monitoring instrument.

4.5 QUALITY CONTROL AND QUALITY ASSURANCE GUIDELINES

To ensure that the data collected during the bagging program

is of the highest quality, the following QC/QA procedures must be

followed. Quality control requirements include procedures to be

4-21
followed when performing equipment leak mass emissions sampling.

Quality assurance requirements include accuracy checks of the

instrumentation used to perform mass emissions sampling. Each of

these QC/QA requirements are discussed below.

4.5.1 Quality Control Procedures

A standard data collection form must be prepared and used

when collecting data in the field. Tables 4-4 and 4-5 are

examples of data collection forms for the blow-through and vacuum

methods of mass emissions sampling, respectively.

In addition to completing the data collection forms, the

following guidelines need to be adhered to when performing the

bagging analysis:

Background levels near equipment that is selected for

bagging must not exceed 10 ppmv, as measured with the

portable monitoring device.

Screening values for equipment that is selected for

bagging must be readable within the spanned range of

the monitoring instruments. If a screening value

exceeds the highest reading on the meter (i.e., "pegged

reading"), a dilution probe should be used, or in the

event that this is not possible, the reading should be

identified as pegged.

Only one piece of equipment can be enclosed per bag; a

separate bag must be constructed for each equipment

component.

A separate sample bag must be used for each equipment

component that is bagged. Alternatively, bags should

be purged and checked for contamination prior to reuse.

A GC must be used to measure the concentrations from

gas samples.

Gas chromatography analyses of bagged samples must

follow the analytical procedures outlined in the EPA

method 18.

To ensure adequate mixing within the bag when using the

blow-through method, the dilution gas must be directed

onto the equipment leak interface.

To ensure that steady-state conditions exist within the

bag, wait at least five time constants (volume of bag

dilution/gas flow rate) before withdrawing a sample for

recording the analysis.

4-22
TABLE 4-4. EXAMPLE DATA COLLECTION FORM FOR FUGITIVE EMISSIONS

BAGGING TEST (BLOW-THROUGH METHOD)

Equipment Type Component ID

Equipment Category Plant ID

Line Size Date

Stream Phase (G/V, LL, HL) Analysis Team

Barometric Pressure

Ambient Temperature Instrument ID

Stream Temperature Stream Pressure

Stream Composition (Wt %) ,

, ,

Time Bagging Test Measurement Data

Initial Screening (ppmv) Equipment Piece Bkgd.

Background Bag Organic Compound Conc. (ppmv)a

Dilution Gas Flow Rate ( /min)

Sample Bag 1 Organic Compound Conc. (ppmv)

O2 Concentration (volume %)

Bag Temperature (°C)

Dilution Gas Flow Rate ( /min)

Sample Bag 2 Organic Compound Conc. (ppmv)

O2 Concentration (volume %)

Bag Temperature (°C)

Condensate Accumulation: Starting Time Final Time

Organic Condensate Collected (m )

Density of Organic Condensate (g/m )

Final Screening (ppmv) Equipment Piece Bkgd.

aCollection of a background bag is optional. However, it is

recommended in cases where the screening value is less than

10 ppmv and there is a detectable oxygen level in the bag.

4-23
TABLE 4-5. EXAMPLE DATA COLLECTION FORM FOR FUGITIVE EMISSIONS

BAGGING TEST (VACUUM METHOD)

Equipment Type Component ID

Equipment Category Plant ID

Line Size Date

Stream Phase (G/V, LL, HL) Analysis Team

Barometric Pressure

Ambient Temperature Instrument ID

Stream Temperature Stream Pressure

Stream Composition (Wt %) ,

, ,

Time Bagging Test Measurement Data

Initial Screening (ppmv) Equipment Piecea Bkgd.

Background Bag Organic Compound Conc. (ppmv)b

Dry Gas Meter Reading ( /min)

Sample Bag 1 Organic Compound Conc. (ppmv)

Vacuum Check in Bag (Y/N) (Must be YES to collect sample.)

Dry Gas Meter Temperaturec (°C)

Dry Gas Meter Pressurec (mmHg)

Dry Gas Meter Reading ( /min)

Sample Bag 2 Organic Compound Conc. (ppmv)

Vacuum Check in Bag (Y/N) (Must be YES to collect sample.)

Dry Gas Meter Temperaturec (°C)

Dry Gas Meter Pressurec (mmHg)

Condensate Accumulation: Starting Time Final Time

Organic Condensate Collected (m )

Density of Organic Condensate (g/m )

Final Screening (ppmv) Equip. Piecea Bkgd.

aThe vacuum method is not recommended if the screening value is

approximately 10 ppmv or less.

bCollection of a background bag is optional.

cPressure and temperature are measured at the dry gas meter.

4-24
The carrier gas used in the blow-through method of

bagging should be analyzed by GC before it is used, and

the concentration of organic compounds in the sample

should be documented. For cylinder purge gases, one

gas sample should be analyzed. For plant purge gas

systems, gas samples should be analyzed with each

bagged sample unless plant personnel can demonstrate

that the plant gas remains stable enough over time to

allow a one-time analysis.

The portable monitoring instrument calibration

procedure described in section 4.4.4 should be

performed at the beginning and end of each day.

4.5.2 Quality Assurance Procedures

Accuracy checks on the laboratory instrumentation and

portable monitoring device must be performed to ensure data

quality. These checks include a leak rate check performed in the

laboratory, blind standards to be analyzed by the laboratory

instrumentation, and drift checks on the portable monitoring

device.

4.5.2.1 Leak Rate Check

A leak rate check is normally performed in the laboratory by

sampling an artificially induced leak rate of a known gas. This

can clarify the magnitude of any bias in the combination of

sampling/test method, and defines the variance in emissions

estimation due to the sampling. If the result is outside the

80 to 120 percent recovery range, the problem must be

investigated and corrected before sampling continues. The

problems and associated solutions should be noted in the test

report.

Leak rate checks should be performed at least two times per

week during the program. The leak rate checks should be

conducted at two concentrations: (1) within the range of 10

multiplied by the calculated lower limit of detection for the

laboratory analytical instrument; and (2) within 20 percent of

the maximum concentration that has been or is expected to be

detected in the field during the bagging program.

To perform a leak rate check, first induce a known flow rate

with one of the known gas concentrations into a sampling bag.

4-25
For example, this can be done using a gas permeation tube of a

known organic compound constituent. Next, determine the

concentration of the gas using a laboratory analytical instrument

and compare the results to the known gas concentration.

If the calculated leak rate is not within ± 20 percent of

the induced leak rate, further analysis should be performed to

determine the reason.

Areas that can potentially induce accuracy problems include:

Condensation,

Pluggage,

Seal of bag not tight (leakage),

Adsorption onto bag, and

Permeation of bag.

The results of all accuracy checks should be recorded on prepared

data sheets.

4.5.2.2 Blind Standards Preparation and Performance

Blind standards are analyzed by the laboratory

instrumentation to ensure that the instrument is properly

calibrated. Blind standards must be prepared and submitted at

least two times per week during the program. The blind standards

are prepared by diluting or mixing known gas concentrations in a

prescribed fashion so that the resulting concentrations are

known. The analytical results should be within ± 25 percent of

the blind standard gas concentration. If the results are not

within 25 percent of the blind standard concentration, further

analyses must be performed to determine the reason. Use of blind

standards not only defines the analytical variance component and

analytical accuracy, but it can serve to point out equipment

malfunctions and/or operator error before questionable data are

generated.

4.5.2.3 Drift Checks

Drift checks need to be performed to ensure that the

portable monitoring instrument remains calibrated. At a minimum,

drift checks must be performed before and after a small group of

components (i.e., two or three) are bagged. Preferably, drift

4-26
checks should be performed on the screening instrument

immediately before and after each component is bagged. These

checks should be performed by analyzing one of the calibration

gases used to calibrate the portable monitoring instrument. The

choice of calibration gas concentration should reflect the

anticipated screening value of the next component to be

monitored. For example, if a component had previously screened

at 1,000 ppmv and been identified for bagging, the calibration

standard should be approximately 900 ppmv.

Drift check data must be recorded on data sheets containing

the information shown in the example in table 4-6. If the

observed instrument reading is different from the certified value

by greater than ± 20 percent, then a full multipoint calibration

must be performed (see section 3.2.4.1). Also, all those

components analyzed since the last drift check must be retested.

Drift checks should also be performed if flameout of the

portable monitoring instrument occurs. Using the lowest

calibration gas standard (i.e., approximately 9 ppmv standard),

determine the associated response on the portable monitoring

instrument. If the response is not within ± 10 percent of the

calibration gas concentration, a full multipoint calibration is

required before testing resumes.

4-27
TABLE 4-6. EXAMPLE DRIFT TEST REPORT FORM

Plant ID

Instrument ID

Analyst Name

Date

Standard

Gas Conc.

(ppmv) Time

Measured

Conc.

(ppmv)

%

Errora

ID Number of

Component Bagged

Since Last Test

a% Error = Certified Conc. - Measured Conc. * 100

Certified Conc.

4-28
4.6 REFERENCES

1. Code of Federal Regulations, Title 40, Part 60, Appendix A.

Reference Method 21, Determination of Volatile Organic

Compound Leaks. Washington, DC. U.S. Government Printing

Office. Revised June 22, 1990.

4-29
5.0 ESTIMATION OF CONTROL EFFICIENCIES FOR

EQUIPMENT LEAK CONTROL TECHNIQUES

5.1 INTRODUCTION

In this chapter, control techniques for reducing equipment

leak emissions are described. There are two primary techniques

for reducing equipment leak emissions: (1) modifying or

replacing existing equipment, and (2) implementing a leak

detection and repair (LDAR) program.

Modifying or replacing existing equipment is referred to in

this chapter as an "equipment modification." Examples of

equipment modifications include installing a cap on an open-ended

line, replacing an existing pump with a sealless type, and

installing on a compressor a closed-vent system that collects

potential leaks and routes them to a control device. In

section 5.2, possible equipment modifications for each of the

equipment types are briefly described. Also, the estimated

control efficiency is presented for each equipment modification.

An LDAR program is a structured program to detect and repair

equipment that is identified as leaking. The focus of this

chapter is LDAR programs for which a portable monitoring device

is used to identify equipment leaks from individual pieces of

equipment. In section 5.3, an approach is presented for

estimating the control effectiveness of an LDAR program.

5.2 EQUIPMENT MODIFICATION CONTROL EFFICIENCY

Controlling emissions by modifying existing equipment is

achieved by either installing additional equipment that

eliminates or reduces emissions, or replacing existing equipment

with sealless types. Equipment modifications for each equipment

type are described in the following sections. A separate section

5-1
is included on closed-vent systems, which can be installed on

more than one type of equipment. Equipment modifications that

can be used for each equipment type are summarized in table 5-1.

Table 5-1 also contains an approximate control efficiency for

each modification.

5.2.1 Closed-Vent Systems

A closed-vent system captures leaking vapors and routes them

to a control device. The control efficiency of a closed-vent

system depends on the percentage of leaking vapors that are

routed to the control device and the efficiency of the control

device. A closed-vent system can be installed on a single piece

of equipment or on a group of equipment pieces. For use on

single pieces of equipment, closed-vent systems are primarily

applicable to equipment types with higher potential emission

rates, such as pumps, compressors, and pressure relief devices.

5.2.2 Pumps

Equipment modifications that are control options for pumps

include routing leaking vapors to a closed-vent system

(as discussed in section 5.2.1), installing a dual mechanical

seal containing a barrier fluid, or replacing the existing pump

with a sealless type.

5.2.2.1 Dual Mechanical Seals. A dual mechanical seal

contains two seals between which a barrier fluid is circulated.

Depending on the design of the dual mechanical seal, the barrier

fluid can be maintained at a pressure that is higher than the

pumped fluid or at a pressure that is lower than the pumped

fluid. If the barrier fluid is maintained at a higher pressure

than the pumped fluid, the pumped fluid will not leak to the

atmosphere. The control efficiency of a dual mechanical seal

with a barrier fluid at a higher pressure than the pumped fluid

is essentially 100 percent, assuming both the inner and outer

seal do not fail simultaneously.

If the barrier fluid is maintained at a lower pressure than

the pumped fluid, a leak in the inner seal would result in the

pumped fluid entering the barrier fluid. To prevent emissions of

the pumped fluid to the atmosphere, a barrier fluid reservoir

5-2
TABLE 5-1. SUMMARY OF EQUIPMENT MODIFICATIONS

Equipment type Modification

Approximate

control

efficiency

(%)

Pumps Sealless design

Closed-vent system

Dual mechanical seal with

barrier fluid maintained at a

higher pressure than the pumped

fluid

100a

90b

100

Compressors Closed-vent system

Dual mechanical seal with

barrier fluid maintained at a

higher pressure than the

compressed gas

90b

100

Pressure relief

devices

Closed-vent system

Rupture disk assembly

c

100

Valves Sealless design 100a

Connectors Weld together 100

Open-ended

lines

Blind, cap, plug, or second

valve

100

Sampling

connections

Closed-loop sampling 100

aSealless equipment can be a large source of emissions in the

event of equipment failure.

bActual efficiency of a closed-vent system depends on percentage

of vapors collected and efficiency of control device to which

the vapors are routed.

cControl efficiency of closed vent-systems installed on a

pressure relief device may be lower than other closed-vent

systems, because they must be designed to handle both

potentially large and small volumes of vapor.

5-3
system should be used. At the reservoir, the pumped fluid can

vaporize (i.e., de-gas) and then be collected by a closed-vent

system.

The actual emissions reduction achievable through use of

dual mechanical seals depends on the frequency of seal failure.

Failure of both the inner and outer seals could result in

relatively large releases of the process fluid. Pressure

monitoring of the barrier fluid may be used to detect failure of

the seals, allowing for a quick response to a failure.

5.2.2.2 Sealless Pumps. When operating properly, a

sealless pump will not leak because the process fluid cannot

escape to the atmosphere. Sealless pumps are used primarily in

processes where the pumped fluid is hazardous, highly toxic, or

very expensive, and where every effort must be made to prevent

all possible leakage of the fluid. Under proper operating

conditions, the control efficiency of sealless pumps is

essentially 100 percent; however, if a catastrophic failure of a

sealless pump occurs, there is a potential for a large quantity

of emissions.

5.2.3 Compressors

Emissions from compressors may be reduced by collecting and

controlling the emissions from the seal or by improving seal

performance. Shaft seals for compressors are of several

different types--all of which restrict but do not eliminate

leakage. In some cases, compressors can be equipped with ports

in the seal area to evacuate collected gases using a closed-vent

system. Additionally, for some compressor seal types, emissions

can be controlled by using a barrier fluid in a similar manner as

described for pumps.

5.2.4 Pressure Relief Valves

Equipment leaks from pressure relief valves (PRV’s) occur as

a result of improper reseating of the valve after a release, or

if the process is operating too close to the set pressure of the

PRV and the PRV does not maintain its seal. Emissions occurring

from PRV’s as a result of an overpressure discharge are not

considered to be equipment leak emissions. There are two primary

5-4
alternatives for controlling equipment leaks from pressure relief

devices: use of a rupture disk (RD) in conjunction with the PRV,

or use of a closed-vent system.

5.2.4.1 Rupture Disk/Pressure Relief Valve Combination.

Although they are also pressure relief devices, RD’s can be

installed upstream of a PRV to prevent fugitive emissions through

the PRV seat. Rupture disk/pressure relief valve combinations

require certain design constraints and criteria to avoid

potential safety hazards, which are not covered in this document.

If the RD fails, it must be replaced. The control efficiency of

the RD/PRV combination is assumed to be 100 percent when operated

and maintained properly.

5.2.4.2 Closed-Vent System. A closed-vent system can be

used to transport equipment leaks from a pressure relief device

to a control device such as a flare. The equipment leak control

efficiency for a closed-vent system installed on a pressure

relief device may not be as high as the control efficiency that

can be achieved by installing a closed-vent system on other

equipment types. This is because emissions from pressure relief

devices can be either high flow emissions during an overpressure

incident or low flow emissions associated with equipment leaks,

and it may be difficult to design a control device to efficiently

handle both high and low flow emissions.

5.2.5 Valves

Emissions from process valves can be eliminated if the valve

stem can be isolated from the process fluid. Two types of

sealless valves are available: diaphragm valves and sealed

bellows valves. The control efficiency of both diaphragm and

sealed bellows valves is virtually 100 percent. However, a

failure of these types of valves has the potential to cause

temporary emissions much larger than those from other types of

valves.

5.2.6 Connectors

In cases where connectors are not required for safety,

maintenance, process modification, or periodic equipment removal,

emissions can be eliminated by welding the connectors together.

5-5
5.2.7 Open-Ended Lines

Emissions from open-ended lines can be controlled by

properly installing a cap, plug, or second valve to the open end.

If a second valve is installed, the upstream valve should always

be closed first after use of the valves to prevent the trapping

of fluids between the valves. The control efficiency of these

measures is assumed to be essentially 100 percent.

5.2.8 Sampling Connections

Emissions from sampling connections occur as a result of

purging the sampling line to obtain a representative sample of

the process fluid. Emissions from sampling connections can be

reduced by using a closed-loop sampling system or by collecting

the purged process fluid and transferring it to a control device

or back to the process. The closed-loop sampling system is

designed to return the purged fluid to the process at a point of

lower pressure. A throttle valve or other device is used to

induce the pressure drop across the sample loop. The efficiency

of a closed-loop system is assumed to be 100 percent.

Alternatively, in some cases, sampling connections can be

designed to collect samples without purging the line. If such a

sampling connection is installed and no emissions to the

atmosphere occur when a sample is collected, then the control

efficiency can be assumed to be 100 percent.

5.3 LEAK DETECTION AND REPAIR CONTROL EFFECTIVENESS

An LDAR program is designed to identify pieces of equipment

that are emitting sufficient amounts of material to warrant

reduction of the emissions through repair. These programs are

best applied to equipment types that can be repaired on-line,

resulting in immediate emissions reduction, and/or to equipment

types for which equipment modifications are not feasible. An

LDAR program is best suited to valves and pumps, and can also be

implemented for connectors.

For other equipment types, an LDAR program is not as

applicable. Compressors are repaired in a manner similar to

pumps; however, because compressors ordinarily do not have a

spare for bypass, a process unit shutdown may be required for

5-6
repair. Open-ended lines are most easily controlled by equipment

modifications. Emissions from sampling connections can only be

reduced by changing the method of collecting the sample (since by

definition equipment leak emissions are the material purged from

the line), and cannot be reduced by an LDAR program. Safety

considerations may preclude the use of an LDAR program on

pressure relief valves.

In this section, an approach is presented that can be used

to estimate the control effectiveness of any given LDAR program

for light liquid pumps, gas valves, light liquid valves, and

connectors. The approach is based on the relationship between

the percentage of equipment pieces that are leaking and the

corresponding average leak rate for all of the equipment. In

this approach, the three most important factors in determining

the control effectiveness are: (1) how a "leak" is defined,

(2) the initial leak frequency before the LDAR program is

implemented, and (3) the final leak frequency after the LDAR

program is implemented. The leak definition (or action level) is

the screening value at which a "leak" is indicated if a piece of

equipment screens equal to or greater than that value. The leak

frequency is the fraction of equipment with screening values

equal to or greater than the leak definition.

Once these three factors are determined, a graph that plots

leak frequency versus mass emission rate at several different

leak definitions is used to predict emissions preceding and

subsequent to implementing the LDAR program. In this way the

emissions reduction (i.e., control effectiveness) associated with

the LDAR program can be easily calculated.

A general description of the approach is provided in the

subsections below. This is followed by an example application of

the approach. The approach has been applied to determine the

control effectiveness at Synthetic Organic Chemical Manufacturing

Industry (SOCMI) and refinery process units for the following

LDAR programs: (1) monthly LDAR with a leak definition of 10,000

parts per million by volume (ppmv), (2) quarterly LDAR with a

leak definition of 10,000 ppmv, and (3) LDAR equivalent to that

5-7
specified in the proposed hazardous organic National Emission

Standard for Hazardous Air Pollutants (NESHAP) equipment leaks

negotiated regulation.1 Tables 5-2 and 5-3 summarize the

estimated control effectiveness for the three LDAR programs

mentioned above at SOCMI process units and refineries,

respectively. It should be noted that, to calculate the control

effectiveness values presented in tables 5-2 and 5-3, assumptions

were made that may not necessarily be applicable to specific

process units. For example, the control effectiveness values in

the tables are based on the assumption that the emission rate

prior to implementing the LDAR program is the emission rate that

would be predicted by the average emission factor. The best way

to calculate the effectiveness of an LDAR program is by

collecting and analyzing data at the specific process unit.

5.3.1 Approach for Estimating LDAR Control Effectiveness

As previously stated, the key parameters for estimating the

control effectiveness of an LDAR program are the leak definition,

the initial leak frequency, and the final leak frequency. The

leak definition is a given part of an LDAR program. It can

either be defined by the process unit implementing the program or

by an equipment standard to which the process unit must comply.

After the leak definition is established, the control

effectiveness of an LDAR program can be estimated based on the

average leak rate before the LDAR program is implemented, and the

average leak rate after the program is in place.

Figures 5-1 through 5-4 are graphs presenting mass emission

rate versus leak frequency for SOCMI-type process units at

several leak definitions for gas valves, light liquid valves,

light liquid pumps, and connectors, respectively. Figures 5-5

through 5-8 are graphs presenting mass emission rate versus leak

frequency for refinery process units at several leak definitions

for gas valves, light liquid valves, light liquid pumps, and

connectors, respectively. Figures 5-9 through 5-15 are graphs

presenting mass emission rate versus leak frequency for gas

fittings, light liquid fittings, gas others, light liquid others,

light liquid pumps, gas valves, and light liquid valves, for

5-8
TABLE 5-2. CONTROL EFFECTIVENESS FOR AN LDAR PROGRAM AT A SOCMI PROC

Equipment type and

service

Control effectiveness (%)

Monthly monitoring

10,000 ppmv leak

definition

Quarterly monitoring

10,000 ppmv leak

definition 

Valves - gas 87 67 

Valves - light liquid 84 61 

Pumps - light liquid 69 45 

Connectors - all

b

b 

a Control effectiveness attributable to the requirements of the proposed ha

organic NESHAP equipment leak negotiated regulation are estimated based ospecific leak definitions and performance levels.

b Data are not available to estimate control effectiveness.

5-9
TABLE 5-3. CONTROL EFFECTIVENESS FOR AN LDAR PROGRAM AT A REFINERY PR

Equipment type and

service

Control effectiveness (%)

Monthly monitoring

10,000 ppmv leak

definition

Quarterly monitoring

10,000 ppmv leak

definition 

Valves - gas 88 70 

Valves - light liquid 76 61 

Pumps - light liquid 68 45 

Connectors - all

b

b 

a Control effectiveness attributable to the requirements of the proposed ha

organic NESHAP equipment leak negotiated regulation are estimated based ospecific leak definitions and performance levels.

b Data are not available to estimate control effectiveness.

5-10
Figure 5-1. SOCMI Gas Valve Average Leak Rate Versus Fraction

Leaking at Several Leak Definitions.

5-11
Figure 5-2. SOCMI Light Liquid Valve Average Mass Emission

Rate Versus Fraction Leaking at Several Leak

Definitions

5-12
Figure 5-3. SOCMI Light Liquid Pump Average Leak Rate Versus

Fraction Leaking at Several Leak Definitions

5-13
Figure 5-4. SOCMI Connector Average Leak Rate Versus Fraction

Leaking at Several Leak Definitions.

5-14
Figure 5-5. Refinery Gas Valve Average Leak Rate Versus

Fraction Leaking at Several Leak Definitions

5-15
Figure 5-6. Refinery Light Liquid Valve Average Leak Rate

Versus Fraction Leaking at Several Leak

Definitions

5-16
Figure 5-7. Refinery Light Liquid Pump Average Leak Rate

Versus Fraction Leaking at Several Leak

Definitions

5-17
Figure 5-8. Refinery Connector Average Leak Rate Versus

Fraction Leaking at Several Leak Definitions

5-18
Figure 5-9. Marketing Terminal Gas Fittings Average Leak Rate

Versus Fraction Leaking at Several Leak

Definitions

5-19
Figure 5-10. Marketing Terminal Light Liquid Fittings Average

Leak Rate Versus Fraction Leaking at Several Leak

Definitions

5-20
Figure 5-11. Marketing Terminal Gas Others Average Leak Rate

Versus Fraction Leaking at Several Leak

Definitions

5-21
Figure 5-12. Marketing Terminal Light Liquid Others Average

Leak Rate Versus Fraction Leaking at Several Leak

Definitions

5-22
Figure 5-13. Marketing Terminal Light Liquid Pumps Average Leak

Rate Versus Fraction Leaking at Several Leak

Definitions

5-23
Figure 5-14. Marketing Terminal Gas Valves Average Leak Rate

Versus Fraction Leaking at Several Leak

Definitions

5-24
Figure 5-15. Marketing Terminal Liquid Light Valves Average

Leak Rate Versus Fraction Leaking at Several Leak

Definitions

5-25
marketing terminal process units. Figures 5-16 through 5-34

present mass emission rate as a function of leak frequency for

connectors, flanges, open-ended lines, others, pumps, and valves

at oil and gas production operations. Using these figures, for a

given leak definition, the leak rate before and after the LDAR

program is implemented, along with the corresponding control

effectiveness, can be determined by plotting the initial and

final leak frequency on these graphs. Tables 5-4, 5-5, 5-6, and

5-7 present equations for the lines in each of the SOCMI,

refinery, marketing terminal, and oil and gas production

operations, and graphs, respectively. Appendix G describes the

approach that was used to develop the equations.

Figure 5-35 provides guidance on how to determine the

initial and final leak frequencies. This figure is a simplified

graphical presentation on how the leak frequency will change

after an LDAR program is implemented. When generating the

figure, it was assumed that all equipment pieces are monitored at

the same time. Each occurrence of equipment monitoring is

referred to as a "monitoring cycle," and it is assumed that equal

time periods lapse between monitoring cycles.

From figure 5-35, it can be seen that there is an immediate

reduction in leak frequency after the LDAR program is

implemented, and then the leak frequency will oscillate over

monitoring cycles. This oscillation occurs because between

monitoring cycles a certain percentage of previously non-leaking

equipment will begin to leak. There are four key points on the

graph presented in figure 5-35. These key points are:

Point X - initial leak frequency;

Point Y - leak frequency immediately after monitoring

for and repairing leaking equipment (i.e., immediately

after a monitoring cycle);

Point Z - leak frequency immediately preceding a

monitoring cycle; and

Point F - average leak frequency between monitoring

cycles (final leak frequency).

5-26
Figure 5-16. Oil and Gas Production Gas Connectors Average Leak

Rate Versus Fraction Leaking at Several Leak

Definitions

5-27
Figure 5-17. Oil and Gas Production Light Oil Connectors

Average Leak Rate Versus Fraction Leaking at

Several Leak Definitions

5-28
Figure 5-18. Oil and Gas Production Water/Oil Connectors

Average Leak Rate Versus Fraction Leaking at

Several Leak Definitions

5-29
Figure 5-19. Oil and Gas Production Gas Flanges Average Leak

Rate Versus Fraction Leaking at Several Leak

Definitions

5-30
Figure 5-20. Oil and Gas Production Light Oil Flanges Average

Leak Rate Versus Fraction Leaking at Several Leak

Definitions

5-31
Figure 5-21. Oil and Gas Production Gas Open-Ended Lines

Average Leak Rate Versus Fraction Leaking at

Several Leak Definitions

5-32
Figure 5-22. Oil and Gas Production Heavy Oil Open-Ended Lines

Average Leak Rate Versus Fraction Leaking at

Several Leak Definitions

5-33
Figure 5-23. Oil and Gas Production Light Oil Open-Ended Lines

Average Leak Rate Versus Fraction Leaking at

Several Leak Definitions

5-34
Figure 5-24. Oil and Gas Production Water/Oil Open-Ended Lines

Average Leak Rate Versus Fraction Leaking at

Several Leak Definitions

5-35
Figure 5-25. Oil and Gas Production Gas Other Average Leak Rate

Versus Fraction Leaking at Several Leak

Definitions

5-36
Figure 5-26. Oil and Gas Production Heavy Oil Other Average

Leak Rate Versus Fraction Leaking at Several Leak

Definitions

5-37
Figure 5-27. Oil and Gas Production Light Oil Other Average

Leak Rate Versus Fraction Leaking at Several Leak

Definitions

5-38
Figure 5-28. Oil and Gas Production Water/Oil Other Average

Leak Rate Versus Fraction Leaking at Several Leak

Definitions

5-39
Figure 5-29. Oil and Gas Production Gas Pump Average Leak Rate

Versus Fraction Leaking at Several Leak

Definitions

5-40
Figure 5-30. Oil and Gas Production Light Oil Pumps Average

Leak Rate Versus Fraction Leaking at Several Leak

Definitions

5-41
Figure 5-31. Oil and Gas Production Gas Valves Average Leak

Rate Versus Fraction Leaking at Several Leak

Definitions

5-42
Figure 5-32. Oil and Gas Production Heavy Oil Valves Average

Leak Rate Versus Fraction Leaking at Several Leak

Definitions

5-43
Figure 5-33. Oil and Gas Production Light Oil Valves Average

Leak Rate Versus Fraction Leaking at Several Leak

Definitions

5-44
Figure 5-34. Oil and Gas Production Water/Oil Valves Average

Leak Rate Versus Fraction Leaking at Several Leak

Definitions

5-45
TABLE 5-4. EQUATIONS RELATING AVERAGE LEAK RATE TO FRACTION LEAKING AT 

Equipment type

Leak definition

(ppmv) Equations

a

Gas valve 500 ALR = (0.044 × LKFRAC) + 1

1000 ALR = (0.050 × LKFRAC) + 22000 ALR = (0.057 × LKFRAC) + 45000 ALR = (0.068 × LKFRAC) + 8

10000 ALR = (0.078 × LKFRAC) + 1

Light liquid valve 500 ALR = (0.047 × LKFRAC) + 2

1000 ALR = (0.053 × LKFRAC) + 32000 ALR = (0.061 × LKFRAC) + 55000 ALR = (0.077 × LKFRAC) + 1

10000 ALR = (0.089 × LKFRAC) + 1

Light liquid pump 500 ALR = (0.095 × LKFRAC) + 3

1000 ALR = (0.11 × LKFRAC) + 42000 ALR = (0.13 × LKFRAC) + 65000 ALR = (0.20 × LKFRAC) + 1

10000 ALR = (0.24 × LKFRAC) + 1

Connector 500 ALR = (0.047 × LKFRAC) + 1

1000 ALR = (0.060 × LKFRAC) + 22000 ALR = (0.073 × LKFRAC) + 35000 ALR = (0.092 × LKFRAC) + 5

10000 ALR = (0.11 × LKFRAC) + 8

aALR = Average leak rate (kg/hr per source) and LKFRAC = leak fraction.

5-46
TABLE 5-5. EQUATIONS RELATING AVERAGE LEAK RATE TO FRACTION LEAKING AT R

Equipment type

Leak definition

(ppmv) Equation

a

Gas valve 500 ALR = (0.11 × LKFRAC) + 8.8E-

1000 ALR = (0.13 × LKFRAC) + 1.4E-

10000 ALR = (0.26 × LKFRAC) + 6.0E-

Light liquid valve 500 ALR = (0.038 × LKFRAC) + 2.0E-

1000 ALR = (0.042 × LKFRAC) + 2.8E-

10000 ALR = (0.084 × LKFRAC) + 1.7E-

Light liquid pump 500 ALR = (0.20 × LKFRAC) + 1.3E-

1000 ALR = (0.23 × LKFRAC) + 2.0E-

10000 ALR = (0.43 × LKFRAC) + 1.2E-

Connector 500 ALR = (0.014 × LKFRAC) + 1.3E-

1000 ALR = (0.017 × LKFRAC) + 1.8E-

10000 ALR = (0.037 × LKFRAC) + 6.0E-

aALR = Average leak rate (kg/hr per source) and LKFRAC = leak fraction.

5-47
TABLE 5-6. EQUATIONS RELATING AVERAGE LEAK RATE TO FRACTION

LEAKING AT MARKETING TERMINAL UNITS

Equipment

Type

Leak

Definition

(ppmv) Equationa

Gas

Connector

500 ALR = (0.017 × LKFRAC) + 5.3E-06

1000 ALR = (0.017 × LKFRAC) + 5.3E-06

2000 ALR = (0.034 × LKFRAC) + 5.9E-06

5000 ALR = (0.034 × LKFRAC) + 5.9E-06

10000 ALR = (0.034 × LKFRAC) + 5.9E-06

Light

Liquid

Connector

500 ALR = (0.0021 × LKFRAC) + 7.0E-06

1000 ALR = (0.0028 × LKFRAC) + 7.1E-06

2000 ALR = (0.0042 × LKFRAC) + 7.1E-06

5000 ALR = (0.0058 × LKFRAC) + 7.2E-06

10000 ALR = (0.0065 × LKFRAC) + 7.2E-06

Gas Other 500 ALR = (0.0018 × LKFRAC) + 3.1E-05

1000 ALR = (0.0021 × LKFRAC) + 4.0E-05

2000 ALR = (0.0023 × LKFRAC) + 4.8E-05

5000 ALR = (0.0029 × LKFRAC) + 8.4E-05

10000 ALR = 1.2E-04

Light

Liquid

Other

500 ALR = (0.019 × LKFRAC) + 2.1E-05

1000 ALR = (0.022 × LKFRAC) + 2.2E-05

2000 ALR = (0.025 × LKFRAC) + 2.2E-05

5000 ALR = (0.034 × LKFRAC) + 2.4E-05

10000 ALR = (0.034 × LKFRAC) + 2.4E-05

Light

Liquid Pump

500 ALR = (0.014 × LKFRAC) + 9.6E-05

1000 ALR = (0.018 × LKFRAC) + 1.2E-04

2000 ALR = (0.029 × LKFRAC) + 1.6E-04

5000 ALR = (0.051 × LKFRAC) + 2.1E-04

10000 ALR = (0.077 × LKFRAC) + 2.4E-04

5-48
TABLE 5-6. EQUATIONS RELATING AVERAGE LEAK RATE TO FRACTION

LEAKING AT MARKETING TERMINAL UNITS (CONTINUED)

Equipment

Type

Leak

Definition

(ppmv) Equationa

Gas Valve 500 ALR = (0.0012 × LKFRAC) + 8.9E-06

1000 ALR = (0.0017 × LKFRAC) + 9.2E-06

2000 ALR = (0.0017 × LKFRAC) + 9.2E-06

5000 ALR = (0.0017 × LKFRAC) + 9.2E-06

10000 ALR = 1.3E-05

Light

Liquid

Valve

500 ALR = (0.0045 × LKFRAC) + 9.5E-06

1000 ALR = (0.0052 × LKFRAC) + 9.8E-06

2000 ALR = (0.0077 × LKFRAC) + 1.1E-05

5000 ALR = (0.013 × LKFRAC) + 1.2E-05

10000 ALR = (0.023 × LKFRAC) + 1.5E-05

aALR = Average leak rate (kg/hr per source)

LKFRAC = Leak fraction.

5-49
TABLE 5-7. EQUATIONS RELATING AVERAGE LEAK RATE TO FRACTION

LEAKING AT OIL AND GAS PRODUCTION OPERATION UNITS

Equipment

Type

Leak

Definition

(ppmv) Equationa

Gas

Connector

500 ALR = (0.016 × LKFRAC) + 7.7E-06

1000 ALR = (0.018 × LKFRAC) + 8.0E-06

2000 ALR = (0.020 × LKFRAC) + 8.5E-06

5000 ALR = (0.023 × LKFRAC) + 9.4E-06

10000 ALR = (0.026 × LKFRAC) + 1.0E-05

Light Oil

Connector

500 ALR = (0.016 × LKFRAC) + 7.7E-06

1000 ALR = (0.021 × LKFRAC) + 8.3E-06

2000 ALR = (0.022 × LKFRAC) + 8.6E-06

5000 ALR = (0.025 × LKFRAC) + 9.2E-06

10000 ALR = (0.026 × LKFRAC) + 9.7E-06

Water/Oil

Connector

500 ALR = (0.013 × LKFRAC) + 7.8E-06

1000 ALR = (0.014 × LKFRAC) + 7.9E-06

2000 ALR = (0.016 × LKFRAC) + 8.3E-06

5000 ALR = (0.023 × LKFRAC) + 9.4E-06

10000 ALR = (0.028 × LKFRAC) + 1.0E-05

Gas Flange 500 ALR = (0.043 × LKFRAC) + 1.1E-06

1000 ALR = (0.051 × LKFRAC) + 1.8E-06

2000 ALR = (0.059 × LKFRAC) + 2.6E-06

5000 ALR = (0.075 × LKFRAC) + 4.7E-06

10000 ALR = (0.082 × LKFRAC) + 5.7E-06

Light Oil

Flange

500 ALR = (0.037 × LKFRAC) + 9.4E-07

1000 ALR = (0.046 × LKFRAC) + 1.2E-06

2000 ALR = (0.055 × LKFRAC) + 1.6E-06

5000 ALR = (0.068 × LKFRAC) + 2.1E-06

10000 ALR = (0.073 × LKFRAC) + 2.4E-06

5-50
TABLE 5-7. EQUATIONS RELATING AVERAGE LEAK RATE TO FRACTION

LEAKING AT OIL AND GAS PRODUCTION OPERATION UNITS

(CONTINUED)

Equipment

Type

Leak

Definition

(ppmv) Equationa

Gas

Open-Ended

Line

500 ALR = (0.037 × LKFRAC) + 4.1E-06

1000 ALR = (0.039 × LKFRAC) + 5.0E-06

2000 ALR = (0.045 × LKFRAC) + 7.5E-06

5000 ALR = (0.051 × LKFRAC) + 1.2E-05

10000 ALR = (0.055 × LKFRAC) + 1.5E-05

Heavy Oil

Open-Ended

Line

500 ALR = (0.012 × LKFRAC) + 4.3E-06

1000 ALR = (0.015 × LKFRAC) + 4.9E-06

2000 ALR = (0.020 × LKFRAC) + 6.0E-06

5000 ALR = (0.030 × LKFRAC) + 7.2E-06

10000 ALR = (0.030 × LKFRAC) + 7.2E-06

Light Oil

Open-Ended

Line

500 ALR = (0.030 × LKFRAC) + 3.8E-06

1000 ALR = (0.032 × LKFRAC) + 4.7E-06

2000 ALR = (0.036 × LKFRAC) + 6.7E-06

5000 ALR = (0.040 × LKFRAC) + 9.7E-06

10000 ALR = (0.044 × LKFRAC) + 1.4E-05

Water/Oil

Open-Ended

Line

500 ALR = (0.030 × LKFRAC) + 3.5E-06

1000 ALR = (0.030 × LKFRAC) + 3.5E-06

2000 ALR = (0.030 × LKFRAC) + 3.5E-06

5000 ALR = (0.030 × LKFRAC) + 3.5E-06

10000 ALR = (0.030 × LKFRAC) + 3.5E-06

Gas Other 500 ALR = (0.055 × LKFRAC) + 1.8E-05

1000 ALR = (0.061 × LKFRAC) + 3.1E-05

2000 ALR = (0.066 × LKFRAC) + 4.5E-05

5000 ALR = (0.078 × LKFRAC) + 8.2E-05

10000 ALR = (0.089 × LKFRAC) + 1.2E-04

5-51
TABLE 5-7. EQUATIONS RELATING AVERAGE LEAK RATE TO FRACTION

LEAKING AT OIL AND GAS PRODUCTION OPERATION UNITS

(CONTINUED)

Equipment

Type

Leak

Definition

(ppmv) Equationa

Heavy Oil

Other

500 ALR = (0.0011 × LKFRAC) + 2.1E-05

1000 ALR = (0.0011 × LKFRAC) + 2.1E-05

2000 ALR = 3.2E-05

5000 ALR = 3.2E-05

10000 ALR = 3.2E-05

Light Oil

Other

500 ALR = (0.053 × LKFRAC) + 3.4E-05

1000 ALR = (0.058 × LKFRAC) + 4.4E-05

2000 ALR = (0.067 × LKFRAC) + 6.4E-05

5000 ALR = (0.075 × LKFRAC) + 8.6E-05

10000 ALR = (0.083 × LKFRAC) + 1.4E-04

Water/Oil

Other

500 ALR = (0.066 × LKFRAC) + 2.5E-05

1000 ALR = (0.066 × LKFRAC) + 2.5E-05

2000 ALR = (0.066 × LKFRAC) + 2.5E-05

5000 ALR = (0.066 × LKFRAC) + 2.5E-05

10000 ALR = (0.069 × LKFRAC) + 5.9E-05

Gas Pump 500 ALR = (0.027 × LKFRAC) + 1.1E-04

1000 ALR = (0.052 × LKFRAC) + 2.3E-04

2000 ALR = (0.052 × LKFRAC) + 2.3E-04

5000 ALR = (0.074 × LKFRAC) + 3.5E-04

10000 ALR = (0.074 × LKFRAC) + 3.5E-04

Light Oil

Pump

500 ALR = (0.071 × LKFRAC) + 7.9E-05

1000 ALR = (0.079 × LKFRAC) + 1.5E-04

2000 ALR = (0.082 × LKFRAC) + 1.9E-04

5000 ALR = (0.10 × LKFRAC) + 5.1E-04

10000 ALR = (0.10 × LKFRAC) + 5.1E-04

5-52
TABLE 5-7. EQUATIONS RELATING AVERAGE LEAK RATE TO FRACTION

LEAKING AT OIL AND GAS PRODUCTION OPERATION UNITS

(CONTINUED)

Equipment

Type

Leak

Definition

(ppmv) Equationa

Gas Valve 500 ALR = (0.070 × LKFRAC) + 9.1E-06

1000 ALR = (0.076 × LKFRAC) + 1.1E-05

2000 ALR = (0.083 × LKFRAC) + 1.4E-05

5000 ALR = (0.092 × LKFRAC) + 1.9E-05

10000 ALR = (0.098 × LKFRAC) + 2.5E-05

Heavy Oil

Valve

500 ALR = (0.0013 × LKFRAC) + 7.8E-06

1000 ALR = (0.0013 × LKFRAC) + 7.8E-06

2000 ALR = (0.0013 × LKFRAC) + 7.8E-06

5000 ALR = 8.4E-06

10000 ALR = 8.4E-06

Light Oil

Valve

500 ALR = (0.059 × LKFRAC) + 9.4E-06

1000 ALR = (0.069 × LKFRAC) + 1.2E-05

2000 ALR = (0.075 × LKFRAC) + 1.4E-05

5000 ALR = (0.083 × LKFRAC) + 1.7E-05

10000 ALR = (0.087 × LKFRAC) + 1.9E-05

Water/Light

Oil Valve

500 ALR = (0.022 × LKFRAC) + 8.1E-06

1000 ALR = (0.022 × LKFRAC) + 8.1E-06

2000 ALR = (0.064 × LKFRAC) + 9.7E-06

5000 ALR = (0.064 × LKFRAC) + 9.7E-06

10000 ALR = (0.064 × LKFRAC) + 9.7E-06

aALR = Average leak rate (kg/hr per source)

LKFRAC = Leak fraction.

5-53
The initial leak frequency is the fraction of sources

defined as leaking before the LDAR program is implemented. The

initial leak frequency is point X on figure 5-35. The lower the

leak definition, the higher the initial leak frequency. At a

process unit, the initial leak frequency can be determined based

on collected screening data. If no screening data are available,

the initial leak frequency can be assumed to be equivalent to the

leak frequency associated with the applicable average emission

factor. However, if a process unit already has some type of LDAR

program in place, the average emission factor may overestimate

emissions.

On figures 5-1 through 5-34, the average emission factor for

each equipment type is plotted as a horizontal line. From this

line, an initial leak frequency can be determined for any of the

leak definitions. For example, on figure 5-1, which is for gas

valves, the SOCMI average emission factor equals

0.00597 kilograms per hour (kg/hr). For a leak definition of

500 ppmv, this average emission factor corresponds to a fraction

leaking of approximately 0.136. Similarly, for a leak definition

of 10,000 ppmv, the average emission factor corresponds to a

fraction leaking of 0.075. These points are determined by

finding the intersection of the SOCMI average emission factor

line and the applicable leak definition line and reading off the

corresponding fraction leaking. Alternatively the fraction

leaking associated with the average factor can be calculated

using the equations in tables 5-4, 5-5, 5-6, and 5-7.

The leak frequency immediately after a monitoring cycle is

Point Y on figure 5-35. After an LDAR program is implemented for

a given time period, point Y will reach a "steady-state" value.

As presented in figure 5-35, point Y depends on two key factors:

(1) the percentage of equipment successfully repaired after being

identified as leaking, and (2) the percentage of equipment that

was repaired for which leaks recurred. Two simplifying

assumptions when calculating point Y are: (1) that leaking

equipment is instantaneously repaired, and (2) that the recurring

leaks will occur instantaneously after the equipment is repaired.

5-54
5-55

Figure 5-35. Simplified Graphical Presentation of Changes in

Leak Frequency After Implementation of an LDAR

Program 
Based on these assumptions the value for point Y is calculated

using the following equation:

Yi = Zi - (FR × Zi) + (FR × Zi × R)

where:

Yi = Leak fraction immediately after monitoring cycle i;

Zi = Leak fraction immediately preceding monitoring cycle

i (note that Z1 equals point X.);

R = Fraction of repaired sources for which a leak

immediately recurs; and

FR = Fraction of leaking sources successfully repaired.

Point Z on figure 5-35 is the leak frequency immediately

preceding equipment monitoring. After an LDAR program is

implemented for a given time period, point Z will reach a

"steady-state" value. To go from point Y to point Z on

figure 5-35, the occurrence rate is added to point Y. The

occurrence rate equals the percentage of initially nonleaking

equipment that starts to leak between monitoring cycles. Use the

following equation to go from point Y to point Z:

Zi+1 = Oc × (1 - Yi)+Yi

where:

Zi+1 = Leak fraction immediately preceding monitoring

cycle i + 1;

Oc = Fraction of nonleaking sources which will leak in

the time period between monitoring cycles

(i.e, occurrence rate); and

Yi = Leak fraction immediately after monitoring cycle i.

After several monitoring cycles, the leak frequency will be

found to approximately oscillate between points Y and Z. The

average value of these two "steady-state" values is the final

leak frequency. This is point F on figure 5-35. The final leak

frequency is the average percent of sources that are still

leaking after an LDAR program has been implemented.

Once the initial and final leak frequencies are determined,

they can be entered into the applicable equation from table 5-4

5-56
or table 5-5 to calculate the associated average leak rates at

these leak frequencies. Based on the initial leak rate and the

final leak rate, the control effectiveness for an LDAR program

can be calculated. The control effectiveness is calculated as:

Eff = (ILR-FLR)/ILR × 100

where:

Eff = Control effectiveness (percent);

ILR = Initial leak rate (kg/hr/source); and

FLR = Final leak rate (kg/hr/source).

5.3.2 Example Application of Approach

As previously mentioned, the approach described in

section 5.3.1 was applied to estimate the control effectiveness

for three types of LDAR programs: (1) monthly inspection with a

leak definition of 10,000 ppmv, (2) quarterly inspection with a

leak definition of 10,000 ppmv, and (3) a program complying with

the requirements specified in the proposed hazardous organic

NESHAP equipment leaks negotiated regulation.1 Details of these

calculations are presented in appendix G. As an example of

applying the approach, the control effectiveness for gas valves

at a SOCMI process unit implementing a monthly LDAR program with

a leak definition of 10,000 ppmv is presented in the following

paragraphs.

Table 5-8 presents the SOCMI gas valve occurrence rate,

recurrence rate, unsuccessful repair rate, and initial leak

frequency. (See appendix G for details on how each of these

parameters were determined.) Using the values presented in

table 5-6 and the approach presented in section 5.3.1, the LDAR

control effectiveness can be calculated. Note that figure 5-9 is

also based on monthly monitoring of gas valves in a SOCMI process

unit with a leak definition of 10,000 ppmv, and it is referred to

in this example demonstration.

For gas valves with a leak definition of 10,000 ppmv, the

initial leak frequency is 7.5 percent. This initial leak

frequency value is taken from figure 5-1, by finding the value of

5-57
TABLE 5-8. VALUES USED IN EXAMPLE CALCULATIONa

Source Category: SOCMI

Equipment Type: Gas Valves

LDAR Program: Monthly Monitoring with a Leak Definition

of 10,000 ppmv

Occurrence Rate: 1.00%

Recurrence Rate: 14%

Unsuccessful Repair Rate: 10%

Initial Leak Frequency:b 7.5%

aSee appendix F for information on how the occurrence rate,

recurrence rate, and unsuccessful repair rate were determined.

bBased on the SOCMI average emission factor for gas valves.

5-58
the fraction leaking at the intersection of the SOCMI average

factor line and the 10,000-ppmv leak definition line. The

initial leak rate for this leak frequency is the SOCMI gas valve

average emission factor, which equals 0.00597. After the LDAR

program is implemented and monitoring occurs on a monthly basis,

the steady-state leak frequency immediately after monitoring (see

point Y6 on figure 5-35) equals 0.29 percent. The steady-state

leak frequency prior to monitoring (see point Z6 on figure 5-35)

equals 1.29 percent. This gives an average of 0.79 percent as

the final leak frequency (see point F on figure 5-35). The

calculations performed to determine the final leak frequency are

shown in table 5-9. Once the estimated gas valve final leak

frequency is determined, the associated leak rate can be found

using figure 5-1 or the gas valve equation for a leak definition

of 10,000 ppmv listed on table 5-4. The corresponding leak rate

associated with the final leak frequency of 0.79 percent at a

leak definition of 10,000 ppmv is 0.00075 kg/hr. Thus, the

control effectiveness of a monthly LDAR program with a leak

definition of 10,000 ppmv for gas valves is:

= (0.00597-0.00075)/0.00597 × 100

= 87 percent.

5-59
TABLE 5-9. EXAMPLE CALCULATION TO DETERMINE THE FINAL LEAK FREQUENCY OF SO

IN A MONTHLY MONITORING LDAR PROGRAM WITH A LEAK DEFINITION OF 10,0

Starting parameters Resulting parameters

1. Leak definition:

= 10,000 ppmv

2. Leak occurrence (Oc):

= 1.00 percent

3. Leak recurrence (R):

= 14 percent

4. Successful repair rate (FR):

= 90 percent

5. Initial leak frequency (Point X):

= 7.5 percent

1. Steady-state leak frequency a

monitoring (Point Y

6):

= 0.29 percent

2. Steady-state leak frequency 

prior to monitoring (Point 

= 1.29 percent

3. Final leak frequency (Point 

= 0.79 percent

Calculations

Monitoring cycle

Leak frequency after

monitoring: Point Y

i

(percent)

c

Leak freque

monitoring

(perc

123456

e

1.700.610.360.310.290.29

721111

aRefer to Figure 5-4 for graphical presentation of all points identified in bFinal Leak Frequency equals the average of the prior to monitoring and aft

steady-state leak frequencies.

c

Y

i = Z

i - (FR * Z

i) + (FR * Z

i * R)

d

Z

i + 1 = Oc * (1 - Y

i)+Y

i

eAfter the sixth monitoring cycle, the values for Y

i and Z

i reach steady-st

5-60
5.4 REFERENCES

1. National Emission Standards for Hazardous Air Pollutants for

Source Categories; Organic Hazardous Air Pollutants from the

Synthetic Organic Chemical Manufacturing Industry and Seven

Other Processes. Subpart H--Equipment Leaks. Federal

Register. Vol. 57, No. 252, pp 62765-62785. Washington,

DC. Office of the Federal Register. December 31, 1992.

5-61
APPENDIX A: EXAMPLE CALCULATIONS
A-1. INTRODUCTION

This appendix provides example calculations demonstrating

the approaches described in chapter 2.0. A simple dataset from a

hypothetical process unit is expanded as needed to illustrate how

the data are is used in each approach. Table A-1 summarizes

information used in the example calculations. This information

includes the equipment count, hours of operation, and composition

for each stream. The stream compositions presented in table A-1

are completely hypothetical and were chosen for the sole purpose

of demonstrating the various approaches. Three streams are

presented in table A-1. Note that the hours of operation are

based on the time in which the equipment contains material.

(Even if a process unit is shutdown, if the equipment contains

material, then the shutdown time must still be included in the

hours of operation.)

Two SOCMI equipment type/service categories are used in the

example calculations: pumps/light liquid and valves/gas. The

same technique used for these equipment type/service categories

can be followed for any equipment type/service. In each of the

calculations, emissions are estimated on an annual basis.

The following sections present the example calculations. In

section A-2, the Average Emission Factor Approach is presented.

Section A-3 presents the Screening Ranges Approach. In section

A-4, the EPA Correlation Equation Approach is presented, and in

section A-5, the use of the Unit-Specific Correlation is

discussed. Section A-6 explains how to speciate emissions.

Section A-7 demonstrates three approaches for applying response

factors (RF’s). Section A-8 demonstrates how to annualize

emissions when more than one screening value is collected from

individual equipment pieces over an annual time period.

Section A-9 shows how to estimate VOC emissions when screening

data are collected from equipment containing organic compounds

not classified as VOC’s. Finally, section A-10 addresses

estimating emissions from equipment containing inorganic

compounds.

A-1
TABLE A-1. DATA FOR EXAMPLE CALCULATIONS

Stream ID

Equipment

type/service Equipment count

Hours of

operation

a

(hr/yr)

Stream c

Constituent 

A Pumps/light

liquid

15 8,760 ethyl acrylate

water

B Pumps/light

liquid

12 4,380 ethyl acrylate

styrene

C Valves/gas 40 8,760 ethyl acrylate

ethanewater vapor

aHours or operation include all time in which material is contained in the equipment.

A-2
A-2. AVERAGE EMISSION FACTOR APPROACH

The Average Emission Factor Approach is demonstrated for

Streams A and B, which contain light liquid pumps. The SOCMI

average TOC emission factor for light liquid pumps is

0.0199 kg/hr. Based on this emission factor and data contained

in table A-1, total VOC emissions can be calculated. Note that

the TOC’s in Stream A are also VOC’s and that stream A contains

water, which is not a VOC. This is accounted for when total VOC

emissions are estimated from Stream A. Table A-2 summarizes the

Average Emission Factor Approach calculations.

A-3. SCREENING RANGES APPROACH

The Screening Ranges Approach is demonstrated for Streams A

and B. The calculations for the Screening Ranges Approach are

similar to those used for the Average Emission Factor Approach,

except that an emission factor for each screening value range is

used. In this example, the component screening values are

designated as either less than 10,000 ppmv or equal to or greater

than 10,000 ppmv. It is assumed that none of the light liquid

pumps in Stream A have a screening value greater than or equal to

10,000 ppmv, and one of the light liquid pumps in Stream B

screens greater than 10,000 ppmv. It is also assumed that one of

the pumps in Stream B could not be screened. Emissions from this

pump are calculated using the average emission factor. Table A-3

summarizes the calculations used in the Screening Ranges

Approach.

A-4. EPA CORRELATION EQUATION APPROACH

The EPA Correlation Equation Approach is demonstrated for

Streams A and B. The EPA Correlation Equation Approach involves

entering screening values into a correlation equation to generate

an emission rate for each equipment piece. In table A-4, assumed

screening values and the resulting emissions for each individual

equipment piece are presented. Emissions from the pump that was

not screened are estimated using the average emission factor.

A-3
TABLE A-2. AVERAGE EMISSION FACTOR METHOD

Stream ID

Equipment

count

TOC Emission

factor

(kg/hr/source)

Weight Fraction

of TOC

Hours of operat

(hr/yr)

A 15 0.0199 0.80 8,760 B 12 0.0199 1.00 4,380 

Total Emissions 

aVOC Emissions = (no. of components) × (emission factor) × (wt. fraction TOC) × (WPVOC/WPoperation).

A-4
TABLE A-3. SCREENING VALUE RANGES METHOD

Stream ID

Equipment

count

TOC Emission

factor

(kg/hr/source)

Hours of

operation

(hr/yr)

V

Components screening > 10,000 ppmv

a

B 1 0.243 4,380 

Components screening < 10,000 ppmv

a

A 15 0.00187 8,760 

B 10 0.00187 4,380 

Components not screened

b

B (TOC wt. fraction equal to 1.0) 1 0.0199 4,380 

Total emissions 

aVOC emissions = (no. of components) × (TOC emission factor) × (WPVOC/WPTOC) × (hours of bVOC emissions = (no. of components) × (average TOC emission factor) × (wt. fraction of T(WPVOC/WPTOC) × (hours of operation).

A-5
TABLE A-4. EPA CORRELATION EQUATION METHODa

Equipment ID

Screening value

(ppmv)

TOC mass emissionsb

(kg/yr)

A-1

A-2

A-3

A-4

A-5

A-6

A-7

A-8

A-9

A-10

A-11

A-12

A-13

A-14

A-15

0

0

0

0

0

20

50

50

100

100

200

400

1,000

2,000

5,000

0.066

0.066

0.066

0.066

0.066

2.0

4.2

4.2

7.4

7.4

13

23

49

87

190

Total Stream A Emissions: 390

B-1

B-2

B-3

B-4

B-5

B-6

B-7

B-8

B-9

B-10

B-11

B-12 (100% TOC)

0

0

0

10

30

250

500

2,000

5,000

8,000

25,000

Not screened

0.033

0.033

0.033

0.55

1.4

7.9

14

44

93

140

350

87

Total Stream B Emissions: 740

Total Emissions 1,130

aEquipment type: Light liquid pumps.

Correlation equation: Leak rate (kg/hr) = 1.90×10-5 × (SV)0.824

Default-zero mass emission rate: 7.49 × 10-6 kg/hr

Hours of operation: Stream A = 8,760; Stream B = 4,380.

bVOC Emissions = (correlation equation or default-zero emission

rate) × (WPVOC/WPTOC) × (hours of operation)

cVOC Emissions = (average emission factor) × (wt. fraction

of TOC) × (WPVOC/WPTOC) × (hours of operation)

A-6
A-5. UNIT-SPECIFIC CORRELATION APPROACH

Correlation equations may be developed for specific units

rather than using the more general EPA Correlation Equations.

Appendix B presents details on developing unit-specific

correlations. Once correlations are developed using the approach

outlined in appendix B, they are applied in the same manner as

described for the EPA correlations.

A-6. SPECIATING EMISSIONS

The emission rate of specific compounds in a mixture can be

calculated if the concentration of the compound in the stream is

known. The equation for speciating emissions is

Ex = ETOC × (WPx/WPTOC)

where:

Ex = The mass emissions of organic chemical "x"

from the equipment piece (mass/time);

ETOC = The TOC mass emissions from the individual

equipment piece (mass/time) calculated from

either the Average Emission Factor, Screening

Ranges, Correlation, or Unit-Specific

Correlation approaches;

WPx = The concentration of organic chemical "x" in

the equipment piece (weight percent);

WPTOC = The total TOC concentration in the equipment

piece (weight percent).

See table A-5 for a demonstration of speciating emissions of

Stream B. Because all of the equipment in Stream B contains the

same composition, the emissions can be speciated on a stream-wide

basis.

A-7. RESPONSE FACTORS

Response factors are used to correct screening values to

compensate for variations in a monitor’s response to different

compounds. Determination of whether an adjustment to the

screening value will provide more valid emission estimates can be

made by reviewing RF’s at actual concentrations of 500 ppmv and

10,000 ppmv for the material in the equipment being screened.

A-7
TABLE A-5. SPECIATING EMISSIONS OF STREAM B

a

Method of calculation

Total TOC emission

(kg/yr)

Ethyl acrylate emissions

b

(kg/yr)

Styr

Avg. emission factor 1,050

c 105 

Screening ranges 1,230

d 123 

Correlation equation 740

e 74 

aEquipment type: Light liquid pumps

Total TOC wt. fraction 1.0Ethyl acrylate wt. fraction 0.1Styrene wt. fraction 0.9

bEmissions for species = (total TOC emissions) × (wt. fraction of individual chemical)/(tfraction).cFrom Table A-2.dFrom Table A-3.eFrom Table A-4.

A-8
The RF’s can be taken from table D-1 in appendix D, or may

be calculated based on analytical measurement performed in a

laboratory. For materials with RF’s below three at both actual

concentrations, the screening value does not need to be

corrected. If the RF at either concentration is above three, the

screening value obtained from the monitoring device should be

adjusted.

If it is necessary to adjust the screening value, one of two

approaches can be applied:

(1) Use the higher of either the 500 ppmv or 10,000 ppmv

RF to adjust all screening values, or

(2) Plot the RF versus screening value and determine the

applicable RF for each screening value.

Table D-1 in appendix D presents the RF’s for chemical

compounds at actual concentrations of 500 ppmv and 10,000 ppmv

for several different monitoring devices. For the example

calculations presented here, data for the Foxboro OVA-108 is

utilized. Table A-6 presents the RF’s for ethyl acrylate and

styrene. From table A-6, it can be seen that at both

concentrations, the RF for ethyl acrylate is below three.

Therefore, it is not necessary to adjust any of the screening

values taken from the equipment in Stream A. (The only TOC

constituent in Stream A is ethyl acrylate.) Stream B contains

10 percent ethyl acrylate and 90 percent styrene. The RF’s at

both concentration values for Stream B are calculated using the

following equation:

RFm = 1

n

i 1

(Xi/RFi)

where:

RFm = Response factor of the mixture;

n = Number of constituents in the mixture;

Xi = Mole fraction of constituent i in the mixture; and

A-9
TABLE A-6. APPLICATION OF RESPONSE FACTORS

a

Chemical

Molecular

weight

Mole fractionfor stream B

b

Response factorat actual conc.

of 500 ppmv

Ethyl Acrylate(0.10 wt. frac.)

100.1 0.1036 2.49 

Styrene(0.90 wt. frac.)

104.2 0.8964 1.10 

aResponse factors are taken from Table D-1 in Appendix D and are based on a 

OVA-108 calibrated with methane.

bMole fraction calculated as:

Weight fraction compound i

= MW of compound i

n

∑ Weight fraction compound i

i=1 MW of compound i

A-10
RFi = Response factor of constituent i in the mixture;

The derivation of the above equation is presented in

table A-7. Using the RF’s and mole fraction information from

table A-6, the RF for the mixture in Stream B is calculated as

follows:

RFm(@ 500 ppmv) = (0.1036/2.49 + 0.8963/1.10)-1 = 1.17

and

RFm(@ 10,000 ppmv) = (0.1036/0.72 + 0.8964/6.06)-1 = 3.43

From the above calculations, it can be seen that at an

actual concentration of 10,000 ppmv the RF is above three, which

means the screening values need to be adjusted. Table A-8

demonstrates the simplest approach for adjusting the screening

values. This approach involves multiplying all of the screening

values by whichever RF is higher.

Correcting the screening values by the approach described

above may be inaccurate in some cases. For example, if all or

most of the equipment have low screening values, using the RF

based on an actual concentration of 10,000 ppmv may cause an over

estimate in the calculated emission rate. A more precise

application of RF’s is to plot the RF versus the screening value.

This can be done by fitting a straight line between the RF and

the corresponding screening values associated with the 500 and

10,000 ppmv actual concentrations. For the example case, this is

done as follows.

Screening value associated with actual concentration of

500 ppmv:

= (500 ppmv)/(RF at actual concentration of 500 ppmv)

= 500 ppmv/1.17

= 427 ppmv

A-11
Screening value associated with actual concentration of

10,000 ppmv:

= (10,000 ppmv)/(RF at actual concentration of

10,000 ppmv)

A-12
TABLE A-8. APPLYING RESPONSE FACTORS FROM TABLE C-1a

Equipment ID

Unadjusted

screening value

(ppmv)

Response factor

of mixture

Adjusted

screening value

b

(ppmv)

B-1 0 -- Default zero B-2 0 -- Default zero B-3 0 -- Default zero B-4 10 3.43 34 

B-5 30 3.43 103 B-6 250 3.43 858 

B-7 500 3.43 1,715 B-8 2,000 3.43 6,860 B-9 5,000 3.43 17,150 

B-10 8,000 3.43 27,440 B-11 25,000 3.43 85,750 B-12 Not Screened -- -- 

Total Emissions of Stream B 

aEquipment type: Light liquid pumps

Correlation equation: Leak rate (kg/hr) = 1.90 × 10-5 (SV)0.824

Default-zero mass emission rate: 7.49 × 10-6 kg/hrHours of operation: Stream B = 4,380

bAdjusted SV = (unadjusted SV) × (RF of mixture)cVOC Emission = (correlation equation or default-zero emission rate) × (WPVOC/WPTOC) × (hdVOC Emission = (average emission factor) × (wt. fraction of VOC) × (WPVOC/WPTOC) × (hour

A-13
TABLE A-7. DERIVATION OF EQUATION USED TO ESTIMATE

RESPONSE FACTOR FOR A MIXTURE

(1) Response Factor (RF) Equation:

(2) For a mixture, each compound will contribute to the actual concentration

RF Actual Concentration (ppmv)

Screening Value (ppmv) = ASV

and to the screening value, thus:

A=A1 + A2 + A3 ...=ATOT

SV = SV1 + SV2 + SV3 ...

Thus, the above equation converts to:

(3) The value for the screening value of each individual compound (SVi) is

RF = ATOT

SV1 SV2 SV3 ...

calculated as:

(4) The mole fraction of each individual compound (Xi) is calculated as:

SVi = Ai

RFi

; substituting gives:

RF = ATOT

A1

RF1

A2

RF2

A3

RF3 ...

Thus, the actual concentration of compound i is calculated as:

Xi = Ai

ATOT

;

(5) Thus, the response factor of a mixture is calculated as:

Ai = Xi ATOT; substituting gives:

RF = ATOT

X1ATOT

RF1

X2ATOT

RF2

X3ATOT

RF3 ...

= 1

X1

RF1

X2

RF2

X3

RF3 ...

RF = 1

n

i=1

Xi/RFi

A-14
= 10,000/3.43

= 2,915 ppmv

Figure A-1 plots this screening value/RF relationship.

Table A-9 uses this plot to calculate emissions. Note that in

table A-9, all of the screening values are adjusted. An

alternative would be to adjust only those screening values having

an associated RF greater than three. Note that for all screening

values less than 427 ppmv, the RF calculated at 427 ppmv is

applied, and, similarly, for all screening values above

2,915 ppmv, the RF at 2,915 ppmv is applied.

An alternative to using the RF’s in appendix D is to use the

analytical technique described in chapter 3.0 to determine RF’s

at several different actual concentrations. These RF’s are then

related to the screening value. Once the RF’s and associated

screening values are determined, a first-order or second-order

(if the relationship appears nonlinear) equation can be fitted to

the RF data. Table A-10 demonstrates how the collected data of

RF’s at actual concentrations is converted to RF’s for the

associated screening values. A hypothetical plot of the

RF/screening value relationship is shown in figure A-2.

Table A-11 demonstrates how emissions can then be calculated by

applying the plot. Note that the line is not extrapolated beyond

the highest screening value for which data were obtained.

A-8. ANNUALIZING EMISSIONS

If more than one screening value is obtained from an

equipment piece, all of the screening values can be used to

estimate emissions, as long as the elapsed time between each

screening value obtained is known. This is demonstrated for pump

A-15 in Stream A. Table A-12 shows how emissions are calculated

for each period between the collection of screening values.

Notice that each screening value is used to estimate emissions

since the last screening value was obtained.

A-15
Figure A-1. Response Factor Curve Generated From Response

Factor Data in Table C-1

A-16
TABLE A-9. ESTIMATING EMISSIONS USING RESPONSE FACTORS GENERATED FROM 

Equipment ID

Unadjusted

screening value

(ppmv)

Response factor of

mixture

Adjusted screening

value

b

(ppmv) V

B-1 0 -- Default zero B-2 0 -- Default zero 

B-3 0 -- Default zero B-4 10 1.17 12 B-5 30 1.17 35 B-6 250 1.17 293 B-7 500 1.24 620 B-8 2000 2.62 5,240 

B-9 5000 3.43 17,150 

B-10 8000 3.43 27,440 B-11 25000 3.43 85,750 B-12 Not screened -- -- 

Total Emissions of Stream B 

aEquipment type: Light liquid pumps

Correlation equation: Leak rate (kg/hr) = 1.90 × 10-5 (SV)0.824

Default-zero mass emission rate: 7.49 × 10-6 kg/hrHours of operation: Stream B = 4,380

bAdjusted SV = (unadjusted SV) × (RF of mixture taken from Figure A-1)cVOC Emission = (correlation equation or default-zero emission rate) × (WPVOC/WPTOC) × (hdVOC Emission = (no. of components) × (average emission factor) × (wt. fraction of VOC) × 

(hours of operation)

A-17
TABLE A-10. GENERATION OF HYPOTHETICAL RESPONSE FACTOR DATA FOR

STREAM Ba

Actual

standard gas

concentration

(ppmv) Sample number

Measured

screening

value

(ppmv)

Response

factor

500

500

500

1

2

3

375

390

390

Avg = 385

1.33

1.28

1.28

Avg = 1.30

2,000

2,000

2,000

1

2

3

1,219

1,205

1,258

Avg = 1,227

1.64

1.66

1.59

Avg = 1.63

5,000

5,000

5,000

1

2

3

1,865

1,930

1,872

Avg = 1,889

2.68

2.59

2.67

Avg = 2.65

10,000

10,000

10,000

1

2

3

2,976

3,040

2,994

Avg = 3,003

3.36

3.29

3.34

Avg = 3.33

25,000

25,000

25,000

1

2

3

6,361

6,394

6,476

Avg = 6,410

3.93

3.91

3.86

Avg = 3.90

aThis table is a demonstration of how analytical determination

of response factors can be used to generate a response

factor/screening value relationship.

A-18
Figure A-2. Response Factor Curve Generated by Analytical

Determination of Response Factors

A-19
TABLE A-11. RESPONSE FACTORS GENERATED FROM FIGURE A-2

a

Equipment ID

Unadjusted

screening value

(ppmv)

Response factor

of mixture

Adjusted screening

value

b

(ppmv)

B-1 0 -- Default zero B-2 0 -- Default zero 

B-3 0 -- Default zero 

B-4 10 1.46 15 B-5 30 1.47 44 B-6 250 1.56 390 B-7 500 1.69 845 B-8 2,000 2.31 4,620 B-9 5,000 3.60 18,000 

B-10 8,000 4.20 33,600 

B-11 25,000 4.20 105,000 B-12 Not screened -- -- 

Total Emissions of Stream B 

aEquipment type: Light liquid pumps

Correlation equation: Leak rate (kg/hr) = 1.90 × 10-5 (SV)0.824

Default-zero mass emission rate: 7.49 × 10-6 kg/hrHours of operation: Stream B = 4,380

bAdjusted SV = (unadjusted SV) × (RF of mixture taken from Figure A-2).cVOC Emissions = (correlation equation or default-zero emission rate) × (WPVOC/WPTOC) × (

operation).

dVOC Emission = (no. of components) × (average emission factor) × ( wt. fraction of VOC) 

(hours of operation).

A-20
TABLE A-12. ANNUALIZING EMISSIONS FOR LIGHT LIQUID PUMP A-15a

Hypothetical

date

Screening

value (ppmv)

Hours elapsed

since last

screening

valueb

VOC emissions

since last

screening

valuec (kg)

January 1 5,000 -- --

February 1 0 744 0.006

March 1 0 672 0.005

April 1 8,000 744 23.3

May 1 100 720 0.6

June 1 1,000 744 4.2

July 1 0 720 0.005

August 1 0 744 0.006

September 1 0 744 0.006

October 1 10,000 720 27.0

November 1 0 744 0.006

December 1 0 720 0.005

January 1 0 744 0.006

TOTALS: 8,760 55.1

aEquipment type: Light liquid pumps

Correlation equation: Leak rate (kg/hr) = 1.90 × 10-5 (SV)0.824

Default-zero mass emission rate: 7.49 × 10-6 kg/hr

bHours elapsed since the last screening value was obtained. For

example, the hours elapsed since the screening value obtained on

March 1 are the hours from February 1 to March 1, which equal

24 hr/day × 28 days, or 672 hours.

cVOC Emissions = (correlation equation or default-zero

emission rate) × (WPVOC/WPTOC) × (hours elapsed).

A-21
A-9. ESTIMATING VOC EMISSIONS FROM EQUIPMENT CONTAINING ORGANIC

COMPOUNDS NOT CLASSIFIED AS VOC’s.

Stream C contains ethane, which is an organic compound, but

is not classified as a VOC. When a monitoring instrument is used

to screen equipment in Stream C, the resulting screening value

will include measurement of the ethane. However, the ethane

should not be included in the estimated VOC emission rate.

The following equation is applied to subtract out the ethane

contribution:

EVOC = ETOC × (WPVOC/WPTOC)

where:

EVOC = The VOC mass emissions from the equipment

(kg/hr);

ETOC = The TOC mass emissions from the equipment

(kg/hr); calculated from either the Average

Emission Factor, Screening Ranges,

Correlation, or Unit-Specific Correlation

approaches;

WPVOC = The concentration of VOC in the equipment in

weight percent;

WPTOC = The TOC concentration in the equipment in

weight percent.

The above calculation is demonstrated below by assuming that

screening values have been obtained from equipment in Stream C as

either greater than or equal to 10,000 ppmv or less than

10,000 ppmv. Assume 2 of the 40 gas valves in Stream C screened

above 10,000 ppmv, and the remainder screened below 10,000 ppmv.

Uncorrected VOC emissions are calculated using the Screening

Ranges Approach:

ETOC = (FG × NG) + (FL × NL)

where:

ETOC = TOC emission rate for an equipment type (kg/hr);

FG = Applicable emission factor for sources with

screening values greater than or equal to

10,000 ppmv (kg/hr/source);

A-22
NG = Equipment count (specific equipment type) for

sources with screening values greater than or

equal to 10,000 ppmv;

FL = Applicable emission factor for sources with

screening values less than 10,000 ppmv

(kg/hr/source); and

NL = Equipment count (specific equipment type) for

sources with screening values less than

10,000 ppmv.

Thus,

ETOC = 0.0782 kg/hr×2+ 0.000131 kg/hr × 38

= 0.161 kg/hr

Converting to an annual emission rate gives:

= 0.161 kg/hr × 8,760 hr/yr

= 1,410 kg/yr

Using the weight fraction of the compounds in Stream C given

in table A-1 (65% ethyl acrylate, 25% ethane, and 10% water

vapor), the above emission rate is corrected as follows:

EVOC = ETOC × (WPVOC/WPTOC)

= 1,410 kg/yr × 65/(65 + 25)

= 1,020 kg/yr VOC emissions

A-10. ESTIMATING INORGANIC EQUIPMENT LEAKS

If the hypothetical process unit also had equipment that

contained a volatile inorganic compound, emissions could be

estimated using the following guidelines. If a monitoring device

is not available, the equipment emissions can be calculated using

the Average Emission Factor Approach. If a monitoring device is

available, the best approach for estimating the emissions is to

generate unit specific correlations, but the EPA Correlation

Equations could also be applied as in section A-4. If the

monitoring device cannot accurately predict the screening value

A-23
but can be used to predict concentrations greater than/less than

10,000 ppmv, the emissions may be estimated by applying the

Screening Ranges approach presented in section A-3.

A-24
APPENDIX B:

LEAK RATE/SCREENING VALUE CORRELATION DEVELOPMENT

AND REVISION OF SOCMI CORRELATIONS

AND EMISSION FACTORS
APPENDIX B

The purpose of this appendix is to provide supplemental

information on the approach for developing site-specific

correlations as discussed in chapter 2.0 of this document. Also,

this appendix contains background information on the data

collection and analysis performed to revise the SOCMI

correlations and emission factors, and presents summary

parameters associated with the SOCMI and petroleum industry

correlations. Section B.1 addresses the following:

Analysis of bagging and screening data;

Development of a correlation equation; and

Development of a default-zero leak rate.

Section B.2 addresses the following:

Analysis of new SOCMI bagging data;

Development of revised correlations and default-zero

leak rates;

Development of revised SOCMI emission factors; and

Summary of SOCMI and petroleum industry correlation

parameters.

B.1 DEVELOPMENT OF SITE-SPECIFIC CORRELATION EQUATIONS

Development of site-specific correlations involves bagging

individual pieces of equipment. (Refer to chapter 4.0 for

details on how equipment is bagged.) The emission rate and

associated screening value from several equipment pieces of the

same type (valve, pump, connector, etc.) and service (gas, light

liquid or heavy liquid) are used to develop a correlation. The

correlation predicts a leak rate based on a screening value. To

develop a correlation, "bagging data" must be collected. In this

appendix, "bagging data" refers to data used to estimate the mass

emission rate from an equipment piece, and the screening value

obtained with the portable monitoring instrument when the

equipment piece is bagged.

B.1.1 Preliminary Analysis of Bagging Data.

For the purposes of this discussion, it is assumed the

blow-through method is used to bag the equipment piece. For each

B-1
bagged (tented) equipment piece, two sample bags should be

collected. For each sample bag the following bagging data should

be recorded: (1) total organic compound concentration (ppmv)

measured in the sample bag at the laboratory using a GC or

similar instrument, (2) the mole percent and molecular weight of

each of the constituents in the sample bag (or alternatively in

the process stream contained within the enclosed equipment

piece), (3) the temperature in the tent when the sample bag is

collected, (4) the carrier gas flow rate out of the tent, (5) the

tent oxygen concentration (6) background bag organic compound

concentration measured at the laboratory (optional), and (7) the

density and volume of any organic liquid collected from the

bagged equipment piece and the time in which the liquid

accumulated.

In some cases, the sample bag total organic concentration

will be below the GC minimum detection limit. If this occurs,

one half the GC minimum detection limit should be used to

estimate emissions.

For each sample bag, the vapor leak rate is calculated using

the following equation:

(1.219×10-5)×(Q)×(MW)×(GC)

Vapor leak rate (kg/hr) =

T + 273.15

where:

1.219 x 10-5 = A conversion factor based on the gas constant

and assuming a pressure in the tent of

1 atmosphere (oK × 106 × kg-mol/m3)

Q = Flow rate out of tent (m3/hr)

= N2 flow rate ( /min)

1 [tent oxygen conc. (volume %)/21]

× 0.06 m3/min

/hr

T = Temperature in tent (oC)

B-2
MW = Molecular weight of organic compounds in the sample bag or

alternatively in the process stream contained within the

equipment piece being bagged. For mixtures, MW is

calculated as follows:

MW =

n

i=1

MWi xi

n

i=1

xi

where:

MWi = Molecular weight of organic compound i;

xi = Mole fraction of organic compound i; and

n = Number of organic compounds in the mixture.

GC = Sample bag organic compound concentration. If a background

sample bag is obtained, the value of GC can be corrected for

background organic compound concentration using the

following equation:

where:

GC = SBC Oxy x BBC

21

SBC = Sample bag organic compound concentration

(ppmv);

Oxy = Tent oxygen concentration (volume %); and

BBC = Background sample bag organic compound

concentration.

The vapor leak rate calculated from the two sample bags is

averaged. Added to this average vapor leak rate is the leak rate

of any liquid that is collected in the bag. The liquid leak rate

is calculated as follows:

Liquid leak rate (kg/hr) = ρ VL

16.67 t

B-3
where:

ρ = Density of organic liquid collected

(g/m );

VL = Volume of organic liquid collected (m );

t = Time in which liquid is collected

(minutes); and

16.67 = A conversion factor to adjust term to

units of kilograms per hour

[g × hr/(kg × min)]

Thus, the total emission rate for the bagged equipment piece is

as follows:

Leak rate (kg/hr) = Average vapor leak rate (kg/hr)

+ Liquid leak rate (kg/hr)

The screening value associated with each bagged equipment

piece is calculated by subtracting the background screening value

from the average of the initial and final screening values. In

cases where the background concentration was larger than the

average of the initial and final screening values, the screening

value should be recorded as 0 ppmv.

B.1.2 Correlation Equation Development.

After preliminary analysis of the bagging data is complete,

there will be a mass emission rate and corresponding screening

value associated with each individual equipment piece that was

bagged. All mass emission rate/screening value data pairs with

nonzero screening values are used to develop the site-specific

correlation. Data pairs with a screening value of zero can be

used to develop a default-zero leak rate, and this is discussed

in section B.1.3.

Two terms used in conjunction with developing the

correlation are defined as follows: "log space"--where the

logarithms of both the screening values and mass emission rates

are evaluated, and "arithmetic space"--where the actual screening

values and emission rates are evaluated. The data is first

analyzed in log space to develop an expression relating the

logarithm of the screening value to the logarithm of the mass

B-4
emission rate. This expression is then transformed to arithmetic

space to arrive at the correlation equation.

It is necessary to perform the initial analysis in log space

because both the screening value and mass emission rate data

typically span several orders of magnitude, and the data are not

normally distributed in arithmetic space. Normality of the data

is important for the validity of the statistical procedures being

used. Historically, the data have been shown to be approximately

log-normally distributed.

The first step in the development of the correlation

equation is to calculate the logarithm of each screening value

and mass emission rate. Note that the correlation developed will

be the same whether the natural logarithm or base 10 logarithm is

used. The next step is to perform simple linear (least squares)

regression in log space. The log of the mass emission rate

(dependent variable, Y) is regressed on the log of the screening

value (independent variable, X). The resulting regression line

takes the following form:

where:

Yi = β0 β1 Xi

Yi = Logarithm of the leak rate determined by

bagging equipment piece i;

Xi = Logarithm of the screening value for equipment

piece i;

βo = Intercept of regression line; and

β1 = Slope of regression line.

The value for the slope and intercept are calculated using the

following equations:

β1 = (XY) (X) (Y)

X2 (X)2

B-5
and

where:

β0 = Y β1 X

Once these have been calculated, then the Mean Squared Error

X = Xi

n

Y = Yi

n

XY = Xi Yi

n

X2 = Xi

2

n

n = number of screening/bagging pairs.

(MSE) can be given by:

MSE = 1

n 2

n

i=1

ri2

where:

The slope and intercept and a scale bias correction factor

ri = Yi β0 β1 Xi

(SCBF) are used in the final step to transform the regression

equation from log space to arithmetic space. The transformed

equation is the correlation equation and it is calculated as

follows:

Note that if the natural logarithm of the leak rates and

Leak rate (kg/hr) = SBCF x (e or 10)β0 x (Screening value)β1

screening values is used when developing the regression line,

then the "e" term should be raised to the power of the intercept

B-6
(β0). On the other hand, if the base 10 logarithm of the leak

rates and screening values is used when developing the regression

line, then the "10" term should be raised to the power of the

intercept (β0).

The SBCF is a correction factor which accounts for the

variability of the data in the log space (see discussion in

section 2.3.4). It is obtained by summing a sufficient number

(usually 10-15) of the terms from the infinite series given

below:

(m-1)×T (m-1)3×T2 (m-1)5×T3

SBCF = 1 + + + + ....,

m m2×2!×(m+1) m3×3!×(m+1)×(m+3)

where:

T (when regression performed using base 10 logarithms)

= (MSE/2)×((ln10)2);

T (when regression performed using natural logarithms)

= (MSE/2);

MSE = mean square error from the regression;

ln10 = natural logarithm of 10; and

m = number of data pairs (n) - 1.

B.1.3 Determination of Default Zero and Pegged Mass Emission

Rates

A default zero emission rate can be calculated based on the

emission rates measured from bagged equipment that have a

screening value of zero ppmv. A pegged emisison rate can be

calculated based on the emission rates measured from bagged

equipment that have a screening value reported as pegged. The

first step to determine the default-zero or pegged leak rate is

to take the logarithm of each of the mass emission rates and then

determine the average log leak rate. The average log leak rate

is used to calculate the default-zero or pegged mass emission

rate. Analysis is performed in log space rather than just

determining the arithmetic average because this gives the most

efficient estimator of the default-zero or pegged leak rate. The

average log leak rate and a scale bias correction factor, that

B-7
takes into account the variance of the log mass emission rates,

are then utilized in the following equation to calculate the

default zero leak rate:

Default Zero or pegged Leak Rate = SBCF × (10 or e)LOG:AVG

(kg/hr)

where:

SBCF = Scale bias correction factor for

the logs of the mass emission

rates; and

LOG:AVG = Average of the logs of the mass

emission rates.

The SBCF for the default zero or pegged leak rate determination

is calculated using the same equation for the SBCF as presented

in section B.1.2, with the following two exceptions: (1) the

variance of the log mass emission rates is used in the "T" term,

rather than the regression mean square error (MSE); and (2) the

sample size (n) is used in the "m" term, rather than "n-1". The

variance (S2) of the log mass emission rates is calculated as:

S2 = 1

n 1

n

i=1

(LOG:LEAKi LOG:AVG)2

where:

LOG:LEAKi = Logarithm of leak rate from component i;

LOG:AVG = Average of the logs of the mass emission

rates; and

n = Number of data points.

B.2 DEVELOPMENT OF REVISED SOCMI CORRELATIONS AND FACTORS

In 1990 bagging data were obtained from several ethylene

oxide (EO) and butadiene (BD) producers. Bagging data were

collected from connectors, light liquid pumps, gas valves, and

light liquid valves. In 1987 and 1988 screening data had been

B-8
collected from the same EO/BD process units. These bagging and

screening data were used to revise the SOCMI correlations and

factors.

(Note that as used in the following discussion, "bagging

data" refers to the screening value/mass emission data pairs, and

"screening data" to the data set of screening values collected

independently of the bagging data. Normally, bagging data are

collected from a chosen set of equipment pieces to provide the

best data for developing a correlation. On the other hand,

screening data are collected from all equipment pieces to give a

representative distribution of screening values).

To revise the SOCMI correlations and factors, the data

collected from the EO/BD process units were compared with data

previously collected from SOCMI process units. In the following

discussion this previously collected data are referred to as

"old" data. The old SOCMI bagging data were collected in the

Six-Unit Maintenance Study (EPA-600/S2-81-080). The old SOCMI

screening data were collected in the 24-Unit Study

(EPA-600/2-81-003). The EO/BD data are referred to as "new."

When the data sets are joined, the resulting data set is referred

to as "combined."

B.2.1 Analysis of SOCMI Bagging Data

Following the approach described in section B.1, the new

SOCMI bagging data were analyzed to develop new correlations.

A comparison of the old and new bagging data was performed to

evaluate any differences. Note that for connectors, only new

bagging data were analyzed since connectors were not bagged as

part of the Six-Unit Maintenance Study. Attachment 1 includes

the complete list of each of the emission rate/screening value

datapoints and presents summary tables on the regression

statistics of the old, new, and combined data.

To evaluate the differences between the new and the old data

for light liquid pumps, light liquid valves, and gas valves, the

following statistical tests were applied:

B-9
• Wilcoxon test of paired differences, and

• F-test of statistical parameters.

The statistical tests did not have consistent results for the

three equipment types. For light liquid pumps, no statistically

significant differences were found, for light liquid valves, the

tests indicated significant differences, and for gas valves, the

tests were inconclusive.

A better comparison was a visual comparison of the data

plotted in log space. This comparison was made by developing

plots of the old and new bagging data with regression lines

superimposed. All of the regression equations are plotted in

figures B-1 through B-4. Figure B-1 presents the new bagging

data and regression equation for connectors. Figures B-2 through

B-4 show old and new bagging data superimposed upon the old, new,

and combined regression equations for light liquid pumps, gas

valves, and light liquid valves, respectively. The regression

lines in these four figures are drawn to correspond only to the

data points from which they were derived.

Figures B-2 through B-4 suggest the old and new data points

appear to lie along a common axis with a similar amount of

scatter. Figures B-2 through B-4 also demonstrate that most of

the old data were from equipment which had screening values

exceeding 1,000 ppmv, whereas a significant portion of the new

data came from equipment screening less than 1,000 ppmv. The

correlation derived from combining the old and new bagging data

spans the greatest range of screening values. Additionally, for

each of the equipment types, the combined correlation equation

has the best fit. Since the combined regressions span the

greatest range of screening values and have the best fit, the

combined data set was used to develop the revised SOCMI

correlation equations.

B.2.2 Development of Revised SOCMI Correlations and

Development of Default-Zero Factors.

B-10
B-11

Figure B-1. Connector Regression Equation
B-12

Figure B-2. Light Liquid Pump Regression Equations
B-13

Figure B-3. Gas Valve Regression Equations
B-14

Figure B-4. Light Liquid Valve Regression Equations
After the old and new bagging data were combined, an initial

regression analysis was performed on the logarithms of the

screening values and mass emission rates following the procedures

outlined in section B.1 on the development of correlation

equations. For the combined data sets outliers were removed.

The residuals (differences between measured log mass emission

rates and log mass emission rates predicted by the regression)

were used to flag outliers. A data pair was flagged as an

outlier whenever the absolute value of its studentized residual

(the residual divided by its standard error) was greater than or

equal to 3. These data pairs are indicated as outliers in the

table contained in attachment 1, which lists the screening values

and mass emission rates for the combined bagging data set.

Attachment 2 contains a table listing all of the bagging

data used to develop the default zero mass emission rates. These

data were collected at the EO/BD process units, and were analyzed

using the approach outlined in section B.1.3.

B.2.3 Revision of SOCMI Emission Factors

After the SOCMI correlations were revised, they were

utilized in conjunction with the "old", "new", and "combined"

screening value data sets to revise the SOCMI emission factors.

Recall that the "old" screening data were the data collected in

the SOCMI 24-Unit Study (EPA-600/2-81-003), the "new" screening

data were the data collected from the EO/BD process units in 1987

and 1988, and the combined data were the two data sets combined.

Using screening data in conjunction with the applicable

correlation equation, emission factors are calculated in the

following manner.

(1) Screening values with a value of zero are assigned the

default zero emission rate,

(2) Pegged screening values were assigned the appropriate

pegged emission rate,

(3) All other screening values are entered into the

applicable correlation equation to determine the

associated mass emission rate, and

B-15
(4) The sum of all of the individual emission rates is

divided by the total number of screening values

(i.e., equipment pieces) to give the average factor.

These steps were followed to revise the SOCMI average emission

factors for connectors, light liquid pumps, gas valves, and light

liquid valves. The same approach was used to revise the SOCMI

Screening Range Emission factors (>10,000 ppmv / <10,000 ppmv),

except that the screening values were segregated into the two

ranges to calculate the average of each range.

Consistent with development of the revised SOCMI correlation

equations (which were developed from the combined bagging data

set), the combined screening data set was used to revise the

SOCMI factors. The combined data set has the advantage that it

reflects changes that have occurred in SOCMI process units since

the 24-Unit Study, and contains data from a representative

sampling of SOCMI process units.

To develop the emission factors it was necessary to make

adjustments to a small percentage of the screening values. These

adjustments were applied to large screening values that were

identified as "pegged data." The large screening value data are

important in the emission factor calculations and these

adjustments were made in an attempt to keep as many screening

values in the analysis as possible.

Examination of the frequency distributions of the screening

value data sets revealed spikes near 10,000 ppmv (between 9980

and 10,001 ppmv) and near 100,000 ppmv (between 99,980 and

100,001 ppmv). These spikes indicate that the instrument was

"pegged" or unable to measure the concentration being sampled

because the concentration was beyond the measurement range of the

instrument. It was assumed that screening values pegged at

10,000 ppmv had actual values between 10,000 and 100,000 ppmv,

and that screening values pegged at 100,000 ppmv had actual

values greater than 100,000 ppmv. Because there were several

screening values greater than 10,000 ppmv and 100,000 ppmv that

were not pegged, an average from the two ranges

B-16
(10,000-100,000 ppmv and >100,000 ppv) was calculated to

substitute for the pegged readings. For the 10,000-100,000 ppmv

range, the average was 33,620 ppm and for the greater than

100,000 ppmv range, the average was 302,367 ppm. These averages

were used in the emission factor analysis for pegged data from

the screening data sets. Thus, each pegged screening value was

assigned the applicable average screening value, which was

entered into the correlation to predict emissions.

Attachment 3 lists the average emission factors generated

from each of the screening data sets, using the revised SOCMI

correlations. There are thousands of screening values in the

data sets, and these data sets are not reproduced in this

appendix. Instead, figures plotting the distribution of the

screening values are presented in attachment 3.

B.2.4 Summary of SOCMI and Petroleum Industry Correlation

Parameters

Table B-1 presents the regression line slope and intercept

and the SBCF associated with each of the revised SOCMI and

petroleum industry correlations contained in tables 2-9 and 2-10

of this document.

B-17
TABLE B-1. SUMMARY OF SOCMI AND PETROLEUM INDUSTRY CORRELATION

PARAMETERS.

Equipment type

Regression

intercepta

(β0)

Regression

slope (β0) SBCF

SOCMI Correlations

Gas valves -6.529 0.873 6.315

Light liquid valves -6.069 0.797 7.520

Light liquid pumps -5.273 0.824 3.563

Connectors -6.434 0.885 8.298

Petroleum Industry Correlation

Valves -6.154 0.746 3.27

Pumps -5.014 0.610 5.15

Others -5.575 0.589 5.14

Connectors -6.468 0.735 4.51

Flanges -5.988 0.703 4.48

Open-Ended Lines -6.366 0.704 5.11

aRegression intercepts are based on analysis in log space using

Base 10 logarithms of leak rates in kg/hr.

B-18
APPENDIX B: ATTACHMENT 1

This attachment lists bagging data used to develop the

combined correlation equations for each of the equipment types in

table B-1-1. Also included is a summary table (table B-1-2) of

the regression statistics associated with the old, new, and

combined SOCMI bagging data sets. Note that the regression

statistics presented in table B-1-2 are based on development of

the regression lines using natural log leak rates and natural log

screening values.

B-19
Table B-1-1. Bagging data used to develop the combined correlation equations.

---------------------- Equipment Type=CONNECTOR Service=ALL -----------------------

Natural Natural

Log of Log of

Measured Emission Screening

Plant Data Emission Screening Rate Value

Type Origin Rate (kg/hr) Value (ppmv) (kg/hr) (ppmv)

EO NEW 0.0000000728 299.00 -16.4361 5.7004

EO NEW 0.0000000734 2.00 -16.4271 0.6931

EO NEW 0.0000001004 4.50 -16.1142 1.5041

EO NEW 0.0000001061 0.50 -16.0586 -0.6931

EO NEW 0.0000001101 6.00 -16.0217 1.7918

EO NEW 0.0000001137 0.80 -15.9900 -0.2231

BD NEW 0.0000001265 2.90 -15.8832 1.0647

EO NEW 0.0000001544 21.50 -15.6835 3.0681

EO NEW 0.0000001613 4.25 -15.6400 1.4469

BD NEW 0.0000001620 1.00 -15.6354 0.0000

EO NEW 0.0000001644 2.00 -15.6207 0.6931

EO NEW 0.0000001731 18.50 -15.5693 2.9178

EO NEW 0.0000002953 458.50 -15.0354 6.1280

EO NEW 0.0000002996 0.40 -15.0209 -0.9163

EO NEW 0.0000003195 0.40 -14.9565 -0.9163

BD NEW 0.0000003254 13.80 -14.9382 2.6247

BD NEW 0.0000003346 1.70 -14.9105 0.5306

BD NEW 0.0000003430 1.35 -14.8856 0.3001

BD NEW 0.0000003442 12.75 -14.8819 2.5455

BD NEW 0.0000003939 4.00 -14.7473 1.3863

BD NEW 0.0000003994 10.00 -14.7334 2.3026

EO NEW 0.0000004007 0.80 -14.7300 -0.2231

BD NEW 0.0000004288 4.00 -14.6623 1.3863

BD NEW 0.0000004757 1.50 -14.5586 0.4055

EO NEW 0.0000004798 999.00 -14.5499 6.9068

EO NEW 0.0000005309 399.40 -14.4486 5.9900

EO NEW 0.0000005812 2.75 -14.3582 1.0116

EO NEW 0.0000005944 28.50 -14.3357 3.3499

EO NEW 0.0000006075 128.00 -14.3140 4.8520

BD NEW 0.0000006524 97.00 -14.2426 4.5747

EO NEW 0.0000007355 3.50 -14.1227 1.2528

BD NEW 0.0000007648 3.25 -14.0837 1.1787

BD NEW 0.0000008560 8.50 -13.9710 2.1401

BD NEW 0.0000008798 28.50 -13.9436 3.3499

BD NEW 0.0000008869 2.00 -13.9356 0.6931

EO NEW 0.0000008924 8.30 -13.9293 2.1163

EO NEW 0.0000009888 4.25 -13.8267 1.4469

BD NEW 0.0000010715 17.00 -13.7464 2.8332

EO NEW 0.0000012661 1.00 -13.5795 0.0000

EO NEW 0.0000016351 4.50 -13.3238 1.5041

BD NEW 0.0000017995 4.00 -13.2280 1.3863

BD NEW 0.0000018303 19.25 -13.2110 2.9575

BD NEW 0.0000020777 3.50 -13.0842 1.2528

BD NEW 0.0000022858 3.75 -12.9888 1.3218

EO NEW 0.0000032725 3.00 -12.6300 1.0986

B-20
Table B-1-1. Bagging data used to develop the correlation equations

---------------------- Equipment Type=CONNECTOR Service=ALL -----------------------

(continued)

Natural Natural

Log of Log of

Measured Emission Screening

Plant Data Emission Screening Rate Value

Type Origin Rate (kg/hr) Value (ppmv) (kg/hr) (ppmv)

EO NEW 0.0000036190 1.60 -12.5293 0.4700

BD NEW 0.0000036396 0.80 -12.5236 -0.2231

BD NEW 0.0000038387 8.50 -12.4704 2.1401

EO NEW 0.0000041625 6.50 -12.3894 1.8718

EO NEW 0.0000044784 48.00 -12.3162 3.8712

BD NEW 0.0000046207 7.80 -12.2850 2.0541

BD NEW 0.0000057784 41.50 -12.0614 3.7257

BD NEW 0.0000080668 12.00 -11.7278 2.4849

BD NEW 0.0000095125 100.00 -11.5629 4.6052

EO NEW 0.0000100797 297.00 -11.5050 5.6937

BD NEW 0.0000137255 19.75 -11.1963 2.9832

BD NEW 0.0000140845 4.50 -11.1704 1.5041

BD NEW 0.0000140911 14.00 -11.1700 2.6391

EO NEW 0.0000142252 63.50 -11.1605 4.1510

BD NEW 0.0000143958 195.50 -11.1486 5.2756

BD NEW 0.0000151611 16.00 -11.0968 2.7726

BD NEW 0.0000161064 13.50 -11.0363 2.6027

EO NEW 0.0000166253 18.50 -11.0046 2.9178

BD NEW 0.0000168916 195.00 -10.9887 5.2730

EO NEW 0.0000178679 0.95 -10.9325 -0.0513

BD NEW 0.0000183124 123.50 -10.9079 4.8162

BD NEW 0.0000191290 4995.00 -10.8643 8.5162

BD NEW 0.0000194650 16.50 -10.8469 2.8034

EO NEW 0.0000197515 50.50 -10.8323 3.9220

BD NEW 0.0000198244 23.00 -10.8286 3.1355

BD NEW 0.0000227951 320.50 -10.6890 5.7699

BD NEW 0.0000279813 67.00 -10.4840 4.2047

BD NEW 0.0000348217 18.00 -10.2653 2.8904

BD NEW 0.0000351763 195.50 -10.2551 5.2756

BD NEW 0.0000359334 9.00 -10.2338 2.1972

BD NEW 0.0000403480 198.00 -10.1180 5.2883

BD NEW 0.0000423987 472.00 -10.0684 6.1570

BD NEW 0.0000445724 13.00 -10.0184 2.5649

EO NEW 0.0000509982 25.00 -9.8837 3.2189

EO NEW 0.0000512445 323.00 -9.8789 5.7777

BD NEW 0.0000595643 275.00 -9.7285 5.6168

BD NEW 0.0000758688 35.00 -9.4865 3.5553

BD NEW 0.0000860423 98.00 -9.3607 4.5850

BD NEW 0.0000910990 1049.00 -9.3036 6.9556

BD NEW 0.0000947099 94.40 -9.2647 4.5475

BD NEW 0.0001007398 197.50 -9.2030 5.2857

BD NEW 0.0001051050 38.80 -9.1606 3.6584

BD NEW 0.0001178839 94.80 -9.0458 4.5518

BD NEW 0.0001397861 371.00 -8.8754 5.9162

B-21
Table B-1-1. Bagging data used to develop the correlation equations

---------------------- Equipment Type=CONNECTOR Service=ALL -----------------------

(continued)

Natural Natural

Log of Log of

Measured Emission Screening

Plant Data Emission Screening Rate Value

Type Origin Rate (kg/hr) Value (ppmv) (kg/hr) (ppmv)

BD NEW 0.0001721438 54.90 -8.6672 4.0055

BD NEW 0.0001806903 4747.00 -8.6187 8.4653

BD NEW 0.0002038979 895.00 -8.4979 6.7968

BD NEW 0.0002463283 97.00 -8.3088 4.5747

BD NEW 0.0002731277 549.00 -8.2056 6.3081

BD NEW 0.0002853205 345.00 -8.1619 5.8435

BD NEW 0.0003727741 198.50 -7.8945 5.2908

BD NEW 0.0004184529 199.00 -7.7789 5.2933

BD NEW 0.0005627360 195.00 -7.4827 5.2730

EO NEW 0.0008093015 997.00 -7.1193 6.9048

BD NEW 0.0008566981 99.00 -7.0624 4.5951

BD NEW 0.0013381945 1049.00 -6.6164 6.9556

BD NEW 0.0013408366 999.00 -6.6145 6.9068

BD NEW 0.0017192076 471.50 -6.3659 6.1559

BD NEW 0.0021650014 1997.00 -6.1353 7.5994

BD NEW 0.0085056085 2999.00 -4.7670 8.0060

BD NEW 0.0101785661 3996.00 -4.5875 8.2930

BD NEW 0.0587476684 99998.80 -2.8345 11.5129

N = 107 (0 outliers)

B-22
Table B-1-1. Bagging data used to develop the correlation equations

------------------------ Equipment Type=PUMP Service=LL ------------------------

Natural Natural

Log of Log of

Measured Emission Screening

Plant Data Emission Screening Rate Value Outlier

Type Origin Rate (kg/hr) Value (ppmv) (kg/hr) (ppmv) Flag

BD NEW 0.0000003333 3.00 -14.9141 1.0986

BD NEW 0.0000003346 64.40 -14.9104 4.1651 OUTLIER

BD NEW 0.0000004908 1.30 -14.5272 0.2624

EO NEW 0.0000012091 4.00 -13.6256 1.3863

BD NEW 0.0000021532 9.50 -13.0486 2.2513

EO NEW 0.0000038359 768.00 -12.4711 6.6438 OUTLIER

EO NEW 0.0000055733 49.00 -12.0975 3.8918

EO NEW 0.0000067016 8.40 -11.9132 2.1282

RE OLD 0.0000068315 42.53 -11.8940 3.7503

EO NEW 0.0000115240 3.00 -11.3711 1.0986

EO NEW 0.0000137032 1.00 -11.1979 0.0000

BD NEW 0.0000173708 15.00 -10.9607 2.7081

RE OLD 0.0000182707 83.26 -10.9102 4.4220

BD NEW 0.0000218470 21.00 -10.7314 3.0445

BD NEW 0.0000234610 8.00 -10.6602 2.0794

BD NEW 0.0000243023 10.00 -10.6249 2.3026

BD NEW 0.0000262744 95.00 -10.5469 4.5539

RE OLD 0.0000273344 647.80 -10.5074 6.4736

BD NEW 0.0000287475 7.80 -10.4570 2.0541

RE OLD 0.0000343297 719.36 -10.2795 6.5784

EO NEW 0.0000385230 13.90 -10.1643 2.6319

BD NEW 0.0000418537 394.00 -10.0813 5.9764

BD NEW 0.0000474696 4.00 -9.9554 1.3863

EO NEW 0.0000588925 2.75 -9.7398 1.0116

BD NEW 0.0000715064 33.00 -9.5457 3.4965

EO NEW 0.0000722114 180.00 -9.5359 5.1930

BD NEW 0.0000978468 1.00 -9.2321 0.0000

BD NEW 0.0001152858 2.75 -9.0681 1.0116

EO NEW 0.0001232483 74.00 -9.0013 4.3041

EO NEW 0.0001803724 44.00 -8.6205 3.7842

RE OLD 0.0001957145 47.12 -8.5389 3.8526

RE OLD 0.0001991513 49.68 -8.5214 3.9057

RE OLD 0.0002209241 744.91 -8.4177 6.6133

BD NEW 0.0002667811 892.50 -8.2291 6.7940

RE OLD 0.0002999432 2388.28 -8.1119 7.7783

BD NEW 0.0003013546 65.00 -8.1072 4.1744

RE OLD 0.0004782523 49.86 -7.6454 3.9091

EO NEW 0.0005168934 105.00 -7.5677 4.6540

EO NEW 0.0005477897 499.00 -7.5096 6.2126

RE OLD 0.0005646821 16033.45 -7.4792 9.6824

EO NEW 0.0005681949 595.00 -7.4730 6.3886

EO NEW 0.0005857415 349.00 -7.4426 5.8551

RE OLD 0.0006402389 3102.49 -7.3537 8.0400

EO NEW 0.0006886734 199.00 -7.2807 5.2933

BD NEW 0.0007364641 598.00 -7.2137 6.3936

B-23
Table B-1-1. Bagging data used to develop the correlation equations

------------------------ Equipment Type=PUMP Service=LL ------------------------

(continued)

Natural Natural

Log of Log of

Measured Emission Screening

Plant Data Emission Screening Rate Value Outlier

Type Origin Rate (kg/hr) Value (ppmv) (kg/hr) (ppmv) Flag

RE OLD 0.0007563452 1378.39 -7.1870 7.2287

RE OLD 0.0007987816 8095.43 -7.1324 8.9991

RE OLD 0.0009912542 289.26 -6.9165 5.6673

BD NEW 0.0010889569 471.00 -6.8225 6.1549

RE OLD 0.0011480956 521.79 -6.7697 6.2573

BD NEW 0.0012930833 348.00 -6.6507 5.8522

RE OLD 0.0013248663 2221.10 -6.6264 7.7058

BD NEW 0.0014886548 3197.00 -6.5099 8.0700

EO NEW 0.0016401471 101.20 -6.4130 4.6171

RE OLD 0.0017660014 24145.32 -6.3390 10.0918

BD NEW 0.0018539657 299.00 -6.2904 5.7004

BD NEW 0.0021087390 997.00 -6.1617 6.9048

EO NEW 0.0022296212 2000.00 -6.1059 7.6009

BD NEW 0.0023007567 5499.25 -6.0745 8.6124

BD NEW 0.0025947420 1993.80 -5.9543 7.5978

RE OLD 0.0027435637 2125.99 -5.8985 7.6620

RE OLD 0.0029144932 5870.47 -5.8381 8.6777

BD NEW 0.0029456140 5.75 -5.8274 1.7492

BD NEW 0.0033415187 125.00 -5.7013 4.8283

BD NEW 0.0036014533 1899.00 -5.6264 7.5491

BD NEW 0.0036569429 1393.90 -5.6111 7.2399

EO NEW 0.0037009240 3197.50 -5.5992 8.0701

BD NEW 0.0037297151 599.00 -5.5914 6.3953

BD NEW 0.0039913442 700.00 -5.5236 6.5511

RE OLD 0.0041248489 2775.53 -5.4907 7.9286

RE OLD 0.0046220969 16654.09 -5.3769 9.7204

RE OLD 0.0046281246 6538.83 -5.3756 8.7855

BD NEW 0.0050222262 1099.00 -5.2939 7.0022

RE OLD 0.0054013839 9501.80 -5.2211 9.1592

BD NEW 0.0055450728 2998.00 -5.1948 8.0057

RE OLD 0.0070361493 1381.77 -4.9567 7.2311

BD NEW 0.0071307927 27.60 -4.9433 3.3178

BD NEW 0.0081605157 6498.00 -4.8084 8.7792

EO NEW 0.0090139120 7696.90 -4.7090 8.9486

BD NEW 0.0098565101 2548.00 -4.6196 7.8431

BD NEW 0.0101206645 2997.00 -4.5932 8.0054

RE OLD 0.0108936908 12820.53 -4.5196 9.4588

RE OLD 0.0110475772 14254.89 -4.5055 9.5649

BD NEW 0.0115165376 3194.50 -4.4640 8.0692

RE OLD 0.0120415404 20840.78 -4.4194 9.9447

RE OLD 0.0120492786 19187.09 -4.4188 9.8620

BD NEW 0.0126046858 5248.25 -4.3737 8.5656

RE OLD 0.0135546418 15011.05 -4.3010 9.6165

RE OLD 0.0138366847 10491.80 -4.2804 9.2583

B-24
Table B-1-1. Bagging data used to develop the correlation equations

------------------------ Equipment Type=PUMP Service=LL ------------------------

(continued)

Natural Natural

Log of Log of

Measured Emission Screening

Plant Data Emission Screening Rate Value Outlier

Type Origin Rate (kg/hr) Value (ppmv) (kg/hr) (ppmv) Flag

BD NEW 0.0154757686 3998.50 -4.1685 8.2937

BD NEW 0.0155724932 3998.00 -4.1622 8.2935

RE OLD 0.0156873305 300.60 -4.1549 5.7058

RE OLD 0.0159032925 51041.21 -4.1412 10.8404

RE OLD 0.0196113751 88270.79 -3.9316 11.3882

BD NEW 0.0198424922 2748.50 -3.9199 7.9188

BD NEW 0.0219422932 797.00 -3.8193 6.6809

RE OLD 0.0220953073 38632.61 -3.8124 10.5619

BD NEW 0.0221617288 6996.50 -3.8094 8.8532

RE OLD 0.0226278893 12142.30 -3.7886 9.4045

RE OLD 0.0232021936 22078.88 -3.7635 10.0024

RE OLD 0.0258831450 10996.59 -3.6542 9.3053

RE OLD 0.0263221310 8527.17 -3.6373 9.0510

RE OLD 0.0274280572 193253.34 -3.5962 12.1718

RE OLD 0.0300037851 12130.06 -3.5064 9.4034

RE OLD 0.0305561087 16850.04 -3.4882 9.7321

RE OLD 0.0361388265 9472.44 -3.3204 9.1561

RE OLD 0.0371630240 37500.32 -3.2924 10.5321

RE OLD 0.0409811410 12196.61 -3.1946 9.4089

RE OLD 0.0476567087 130564.77 -3.0437 11.7796

RE OLD 0.0480145702 23101.38 -3.0363 10.0476

BD NEW 0.0492542578 5998.00 -3.0108 8.6992

RE OLD 0.0556463965 38446.34 -2.8887 10.5570

RE OLD 0.0572488867 3111.50 -2.8603 8.0429

RE OLD 0.0586671574 41504.10 -2.8359 10.6335

BD NEW 0.0863688407 99996.00 -2.4491 11.5129

RE OLD 0.0977863072 88269.36 -2.3250 11.3881

BD NEW 0.1039387219 5997.00 -2.2640 8.6990

RE OLD 0.1074526291 45285.17 -2.2307 10.7207

BD NEW 0.2535689673 99994.00 -1.3721 11.5129

N = 119 (2 outliers)

B-25
Table B-1-1. Bagging data used to develop the correlation equations

------------------------ Equipment Type=VALVE Service=G ------------------------

Natural Natural

Log of Log of

Measured Emission Screening

Plant Data Emission Screening Rate Value Outlier

Type Origin Rate (kg/hr) Value (ppmv) (kg/hr) (ppmv) Flag

EO NEW 0.0000000717 37.50 -16.4508 3.6243

EO NEW 0.0000000720 35.00 -16.4468 3.5553

EO NEW 0.0000000737 2.00 -16.4235 0.6931

BD NEW 0.0000001062 1.00 -16.0577 0.0000

EO NEW 0.0000001082 4.00 -16.0396 1.3863

EO NEW 0.0000001147 4.00 -15.9811 1.3863

EO NEW 0.0000001167 0.10 -15.9641 -2.3026

EO NEW 0.0000001170 9.00 -15.9608 2.1972

EO NEW 0.0000001172 5.00 -15.9591 1.6094

EO NEW 0.0000001198 4.00 -15.9374 1.3863

EO NEW 0.0000001251 21.50 -15.8945 3.0681

EO NEW 0.0000001525 1.20 -15.6963 0.1823

EO NEW 0.0000001579 1.00 -15.6615 0.0000

EO NEW 0.0000001705 2.00 -15.5848 0.6931

EO NEW 0.0000001964 98.25 -15.4430 4.5875

EO NEW 0.0000002292 3.00 -15.2887 1.0986

EO NEW 0.0000002537 224.30 -15.1869 5.4130

EO NEW 0.0000002824 9.00 -15.0800 2.1972

BD NEW 0.0000003468 6.20 -14.8747 1.8245

BD NEW 0.0000003511 1.75 -14.8622 0.5596

EO NEW 0.0000003724 0.40 -14.8032 -0.9163

BD NEW 0.0000004915 1.00 -14.5259 0.0000

BD NEW 0.0000005202 1.50 -14.4690 0.4055

EO NEW 0.0000005222 108.00 -14.4652 4.6821

EO NEW 0.0000005551 4.00 -14.4041 1.3863

BD NEW 0.0000006288 1.25 -14.2795 0.2231

EO NEW 0.0000007041 0.20 -14.1663 -1.6094

EO NEW 0.0000007204 1497.50 -14.1434 7.3116

BD NEW 0.0000007597 2.50 -14.0903 0.9163

EO NEW 0.0000008744 68.90 -13.9497 4.2327

EO NEW 0.0000010541 198.00 -13.7628 5.2883

BD NEW 0.0000013384 51.50 -13.5241 3.9416

BD NEW 0.0000013799 3499.30 -13.4935 8.1603

BD NEW 0.0000013870 15.70 -13.4884 2.7537

BD NEW 0.0000018645 6.00 -13.1925 1.7918

BD NEW 0.0000018779 1.50 -13.1854 0.4055

EO NEW 0.0000021100 99.00 -13.0688 4.5951

EO NEW 0.0000022366 0.20 -13.0105 -1.6094

EO NEW 0.0000024148 598.00 -12.9339 6.3936

BD NEW 0.0000025627 28.00 -12.8744 3.3322

EO NEW 0.0000034003 678.00 -12.5916 6.5191

BD NEW 0.0000036200 6.00 -12.5290 1.7918

EO NEW 0.0000036375 19.00 -12.5242 2.9444

EO NEW 0.0000038715 118.25 -12.4619 4.7728

EO NEW 0.0000042396 38.40 -12.3710 3.6481

B-26
Table B-1-1. Bagging data used to develop the correlation equations

------------------------ Equipment Type=VALVE Service=G ------------------------

(continued)

Natural Natural

Log of Log of

Measured Emission Screening

Plant Data Emission Screening Rate Value Outlier

Type Origin Rate (kg/hr) Value (ppmv) (kg/hr) (ppmv) Flag

BD NEW 0.0000045549 5.40 -12.2993 1.6864

EO NEW 0.0000056834 9.50 -12.0780 2.2513

BD NEW 0.0000061124 4.00 -12.0052 1.3863

EO NEW 0.0000070548 2.10 -11.8618 0.7419

BD NEW 0.0000074252 17.50 -11.8106 2.8622

BD NEW 0.0000080241 3.40 -11.7331 1.2238

EO NEW 0.0000083624 40.15 -11.6918 3.6926

RE OLD 0.0000118648 20.46 -11.3419 3.0184

BD NEW 0.0000128110 8.50 -11.2652 2.1401

BD NEW 0.0000137662 83.90 -11.1933 4.4296

RE OLD 0.0000149663 4952.69 -11.1097 8.5077

RE OLD 0.0000166075 4954.50 -11.0057 8.5081

RE OLD 0.0000175591 1007.37 -10.9499 6.9151

EO NEW 0.0000214657 698.50 -10.7491 6.5489

BD NEW 0.0000220929 20.50 -10.7203 3.0204

EO NEW 0.0000243523 850.00 -10.6229 6.7452

BD NEW 0.0000246644 144.50 -10.6101 4.9733

BD NEW 0.0000263657 139.25 -10.5434 4.9363

BD NEW 0.0000285391 15.50 -10.4642 2.7408

BD NEW 0.0000298709 109.00 -10.4186 4.6913

RE OLD 0.0000357822 2987.55 -10.2381 8.0022

RE OLD 0.0000359337 2497.04 -10.2338 7.8229

BD NEW 0.0000365393 598.00 -10.2171 6.3936

BD NEW 0.0000395358 3.50 -10.1383 1.2528

BD NEW 0.0000421641 98.50 -10.0739 4.5901

RE OLD 0.0000440123 2282.07 -10.0310 7.7328

EO NEW 0.0000445925 17.50 -10.0179 2.8622

BD NEW 0.0000523996 78.00 -9.8566 4.3567

BD NEW 0.0000557747 119.00 -9.7942 4.7791

RE OLD 0.0000617007 2670.91 -9.6932 7.8902

RE OLD 0.0000647076 1740.60 -9.6456 7.4620

RE OLD 0.0000724907 680.87 -9.5321 6.5234

RE OLD 0.0000779572 1315.53 -9.4594 7.1820

RE OLD 0.0000833618 290.43 -9.3923 5.6714

RE OLD 0.0000996210 700.59 -9.2141 6.5519

RE OLD 0.0001071514 4740.81 -9.1413 8.4640

RE OLD 0.0001137777 4385.68 -9.0813 8.3861

BD NEW 0.0001197735 474.40 -9.0299 6.1621

RE OLD 0.0001341897 987.15 -8.9163 6.8948

RE OLD 0.0001376705 496.21 -8.8906 6.2070

RE OLD 0.0001518078 1224.74 -8.7929 7.1105

RE OLD 0.0001625511 24157.28 -8.7245 10.0923

EO NEW 0.0001720041 498.75 -8.6680 6.2121

RE OLD 0.0001766026 7061.58 -8.6416 8.8624

B-27
Table B-1-1. Bagging data used to develop the correlation equations

------------------------ Equipment Type=VALVE Service=G ------------------------

(continued)

Natural Natural

Log of Log of

Measured Emission Screening

Plant Data Emission Screening Rate Value Outlier

Type Origin Rate (kg/hr) Value (ppmv) (kg/hr) (ppmv) Flag

BD NEW 0.0001866845 824.40 -8.5861 6.7147

RE OLD 0.0001904680 1643.51 -8.5660 7.4046

RE OLD 0.0001964120 1423.98 -8.5353 7.2612

RE OLD 0.0001977607 24689.43 -8.5285 10.1141

RE OLD 0.0002152405 1556.44 -8.4438 7.3502

RE OLD 0.0002180108 2095.88 -8.4310 7.6477

RE OLD 0.0002232184 3292.43 -8.4074 8.0994

RE OLD 0.0002275124 6482.10 -8.3883 8.7768

RE OLD 0.0002307162 4804.03 -8.3743 8.4772

RE OLD 0.0002322459 4368.95 -8.3677 8.3823

BD NEW 0.0002437423 499.40 -8.3194 6.2134

RE OLD 0.0002528838 928.66 -8.2826 6.8337

RE OLD 0.0002757637 877.50 -8.1960 6.7771

BD NEW 0.0002760188 6695.10 -8.1950 8.8091

EO NEW 0.0002904846 8998.00 -8.1440 9.1048

RE OLD 0.0003425098 2139.46 -7.9792 7.6683

EO NEW 0.0003724437 9998.00 -7.8954 9.2101

BD NEW 0.0003991030 394.00 -7.8263 5.9764

RE OLD 0.0004050504 9863.86 -7.8115 9.1966

BD NEW 0.0004404057 1999.00 -7.7278 7.6004

RE OLD 0.0004427801 4287.44 -7.7224 8.3634

RE OLD 0.0004461460 18661.82 -7.7149 9.8342

BD NEW 0.0004471948 799.00 -7.7125 6.6834

RE OLD 0.0004520589 55794.96 -7.7017 10.9294

RE OLD 0.0004529831 4949.37 -7.6997 8.5070

RE OLD 0.0004536846 3965.77 -7.6981 8.2855

RE OLD 0.0004640417 560.84 -7.6755 6.3294

RE OLD 0.0004685177 4279.25 -7.6659 8.3615

RE OLD 0.0004728028 14956.09 -7.6568 9.6129

RE OLD 0.0005228957 4399.96 -7.5561 8.3894

RE OLD 0.0005323154 2867.11 -7.5383 7.9611

RE OLD 0.0005465275 16699.10 -7.5119 9.7231

BD NEW 0.0005634682 2999.70 -7.4814 8.0063

BD NEW 0.0005651718 247.00 -7.4784 5.5094

RE OLD 0.0005730494 2037.49 -7.4645 7.6195

RE OLD 0.0005839129 35105.41 -7.4458 10.4661

RE OLD 0.0005991093 246.51 -7.4201 5.5074

RE OLD 0.0006007199 27836.27 -7.4174 10.2341

RE OLD 0.0006146615 1592.14 -7.3944 7.3728

BD NEW 0.0006404920 2743.50 -7.3533 7.9170

RE OLD 0.0006448431 2313.46 -7.3465 7.7465

BD NEW 0.0007363507 1247.00 -7.2138 7.1285

EO NEW 0.0009188385 3448.00 -6.9924 8.1455

RE OLD 0.0009212745 2316.36 -6.9898 7.7478

B-28
Table B-1-1. Bagging data used to develop the correlation equations

------------------------ Equipment Type=VALVE Service=G ------------------------

(continued)

Natural Natural

Log of Log of

Measured Emission Screening

Plant Data Emission Screening Rate Value Outlier

Type Origin Rate (kg/hr) Value (ppmv) (kg/hr) (ppmv) Flag

RE OLD 0.0009386789 7331.62 -6.9710 8.9000

RE OLD 0.0009859662 32119.44 -6.9219 10.3772

RE OLD 0.0011533445 2785.34 -6.7651 7.9321

RE OLD 0.0011636438 2797.20 -6.7562 7.9364

RE OLD 0.0011668930 203224.00 -6.7534 12.2221

RE OLD 0.0011712242 21751.69 -6.7497 9.9874

RE OLD 0.0017829290 67504.85 -6.3295 11.1200

RE OLD 0.0019401846 56199.96 -6.2450 10.9367

RE OLD 0.0020010182 8684.64 -6.2141 9.0693

RE OLD 0.0022581253 4284.86 -6.0932 8.3628

RE OLD 0.0022870889 3791.44 -6.0805 8.2405

RE OLD 0.0025260448 3163.33 -5.9811 8.0594

RE OLD 0.0025348896 534.08 -5.9776 6.2805

RE OLD 0.0026295658 50201.19 -5.9409 10.8238

RE OLD 0.0027833322 20393.42 -5.8841 9.9230

RE OLD 0.0029409798 4530.72 -5.8290 8.4186

RE OLD 0.0031312882 1860.09 -5.7663 7.5284

BD NEW 0.0031778789 4297.80 -5.7515 8.3659

RE OLD 0.0033409352 219611.97 -5.7015 12.2996

RE OLD 0.0033838729 23015.69 -5.6887 10.0439

RE OLD 0.0036846059 17536.22 -5.6036 9.7720

RE OLD 0.0036971583 16495.48 -5.6002 9.7108

RE OLD 0.0039426484 12647.22 -5.5359 9.4452

RE OLD 0.0039504089 34241.04 -5.5339 10.4412

RE OLD 0.0040050325 1333.88 -5.5202 7.1958

RE OLD 0.0041065399 4005.05 -5.4952 8.2953

RE OLD 0.0041660267 2803.86 -5.4808 7.9388

RE OLD 0.0046273787 20516.30 -5.3758 9.9290

RE OLD 0.0051511364 3629.80 -5.2685 8.1969

RE OLD 0.0060064387 760.42 -5.1149 6.6339

RE OLD 0.0064640997 61150.08 -5.0415 11.0211

RE OLD 0.0067947745 102781.04 -4.9916 11.5404

RE OLD 0.0086599432 287461.04 -4.7490 12.5688

BD NEW 0.0102338821 12994.00 -4.5821 9.4722

RE OLD 0.0112479155 9730.32 -4.4876 9.1830

RE OLD 0.0150883255 749143.47 -4.1938 13.5267

RE OLD 0.0192079955 191834.63 -3.9524 12.1644

RE OLD 0.0212769340 29340.67 -3.8501 10.2867

RE OLD 0.0262475666 189629.11 -3.6402 12.1528

RE OLD 0.0265051976 2373.75 -3.6304 7.7722

RE OLD 0.0277367164 820321.32 -3.5850 13.6175

RE OLD 0.0342721260 90882.86 -3.3734 11.4173

RE OLD 0.0449106195 17031.74 -3.1031 9.7428

RE OLD 0.0645502674 16874.50 -2.7403 9.7336

B-29
Table B-1-1. Bagging data used to develop the correlation equations

------------------------ Equipment Type=VALVE Service=G ------------------------

(continued)

Natural Natural

Log of Log of

Measured Emission Screening

Plant Data Emission Screening Rate Value Outlier

Type Origin Rate (kg/hr) Value (ppmv) (kg/hr) (ppmv) Flag

RE OLD 0.1109042134 326432.21 -2.1991 12.6960

RE OLD 0.1140677949 20836.56 -2.1710 9.9445

N = 179 (0 outliers)

B-30
Table B-1-1. Bagging data used to develop the correlation equations

----------------------- Equipment Type=VALVE Service=LL ------------------------

Natural Natural

Log of Log of

Measured Emission Screening

Plant Data Emission Screening Rate Value Outlier

Type Origin Rate (kg/hr) Value (ppmv) (kg/hr) (ppmv) Flag

EO NEW 0.0000001148 2.00 -15.9798 0.6931

EO NEW 0.0000001182 0.40 -15.9509 -0.9163

EO NEW 0.0000001490 0.70 -15.7195 -0.3567

EO NEW 0.0000001545 7.00 -15.6828 1.9459

BD NEW 0.0000001546 2.00 -15.6825 0.6931

BD NEW 0.0000001705 2.25 -15.5843 0.8109

EO NEW 0.0000001748 13.50 -15.5593 2.6027

BD NEW 0.0000001777 1.50 -15.5431 0.4055

EO NEW 0.0000002092 0.90 -15.3801 -0.1054

EO NEW 0.0000002655 24.25 -15.1418 3.1884

EO NEW 0.0000002662 34.00 -15.1392 3.5264

EO NEW 0.0000002674 119.00 -15.1344 4.7791

EO NEW 0.0000002973 1.00 -15.0285 0.0000

BD NEW 0.0000003209 0.25 -14.9523 -1.3863

BD NEW 0.0000003246 14.00 -14.9406 2.6391

BD NEW 0.0000003272 145.00 -14.9326 4.9767

BD NEW 0.0000003761 1.00 -14.7934 0.0000

EO NEW 0.0000004160 1.10 -14.6925 0.0953

BD NEW 0.0000004269 2.50 -14.6668 0.9163

EO NEW 0.0000005550 0.60 -14.4043 -0.5108

EO NEW 0.0000006711 2.00 -14.2144 0.6931

EO NEW 0.0000006800 1547.50 -14.2011 7.3444

EO NEW 0.0000007182 2.80 -14.1465 1.0296

BD NEW 0.0000007281 1.30 -14.1328 0.2624

EO NEW 0.0000007741 1.85 -14.0715 0.6152

EO NEW 0.0000007760 0.45 -14.0691 -0.7985

BD NEW 0.0000009403 2.25 -13.8770 0.8109

BD NEW 0.0000009766 3.25 -13.8391 1.1787

BD NEW 0.0000010750 3.50 -13.7432 1.2528

BD NEW 0.0000013768 6.45 -13.4957 1.8641

EO NEW 0.0000014189 398.00 -13.4656 5.9865

BD NEW 0.0000017270 4.00 -13.2691 1.3863

B-31
Table B-1-1. Bagging data used to develop the correlation equations

----------------------- Equipment Type=VALVE Service=LL ------------------------

(continued)

Natural Natural

Log of Log of

Measured Emission Screening

Plant Data Emission Screening Rate Value Outlier

Type Origin Rate (kg/hr) Value (ppmv) (kg/hr) (ppmv) Flag

BD NEW 0.0000021600 209.00 -13.0454 5.3423

EO NEW 0.0000026370 6.70 -12.8459 1.9021

BD NEW 0.0000026381 18.50 -12.8455 2.9178

EO NEW 0.0000028522 51.20 -12.7674 3.9357

EO NEW 0.0000031653 21.80 -12.6633 3.0819

RE OLD 0.0000032615 2740.82 -12.6333 7.9160

BD NEW 0.0000034734 13.50 -12.5704 2.6027

BD NEW 0.0000034854 486.75 -12.5669 6.1878

BD NEW 0.0000036357 1.40 -12.5247 0.3365

BD NEW 0.0000036487 3.05 -12.5211 1.1151

BD NEW 0.0000038172 0.20 -12.4760 -1.6094

EO NEW 0.0000038185 45.00 -12.4756 3.8067

EO NEW 0.0000045401 21.50 -12.3026 3.0681

BD NEW 0.0000048429 21.50 -12.2380 3.0681

EO NEW 0.0000053288 11.40 -12.1424 2.4336

EO NEW 0.0000054257 1.00 -12.1244 0.0000

BD NEW 0.0000054590 44.90 -12.1182 3.8044

RE OLD 0.0000061236 5194.17 -12.0034 8.5553

EO NEW 0.0000063620 4.80 -11.9652 1.5686

EO NEW 0.0000076923 30.00 -11.7753 3.4012

BD NEW 0.0000079625 195.50 -11.7408 5.2756

BD NEW 0.0000080291 20.85 -11.7324 3.0374

BD NEW 0.0000081895 17.75 -11.7127 2.8764

BD NEW 0.0000087183 0.25 -11.6501 -1.3863

BD NEW 0.0000090393 7.00 -11.6139 1.9459

EO NEW 0.0000096017 0.90 -11.5536 -0.1054

EO NEW 0.0000106063 29.00 -11.4541 3.3673

BD NEW 0.0000114056 2.40 -11.3814 0.8755

EO NEW 0.0000116662 90.00 -11.3588 4.4998

RE OLD 0.0000118300 97.72 -11.3449 4.5821

BD NEW 0.0000123249 21.90 -11.3039 3.0865

BD NEW 0.0000130315 20.00 -11.2481 2.9957

BD NEW 0.0000136318 49.80 -11.2031 3.9080

EO NEW 0.0000138914 39.40 -11.1842 3.6738

RE OLD 0.0000150006 500.63 -11.1074 6.2159

EO NEW 0.0000150217 108.00 -11.1060 4.6821

BD NEW 0.0000150810 32.50 -11.1021 3.4812

BD NEW 0.0000155478 54.50 -11.0716 3.9982

RE OLD 0.0000185551 78.10 -10.8948 4.3580

RE OLD 0.0000191256 191501.42 -10.8645 12.1627 OUTLIER

RE OLD 0.0000196624 4878.72 -10.8368 8.4926

BD NEW 0.0000200735 250.00 -10.8161 5.5215

BD NEW 0.0000212478 67.00 -10.7593 4.2047

EO NEW 0.0000226439 44.10 -10.6956 3.7865

B-32
Table B-1-1. Bagging data used to develop the correlation equations

----------------------- Equipment Type=VALVE Service=LL ------------------------

(continued)

Natural Natural

Log of Log of

Measured Emission Screening

Plant Data Emission Screening Rate Value Outlier

Type Origin Rate (kg/hr) Value (ppmv) (kg/hr) (ppmv) Flag

EO NEW 0.0000228716 74.80 -10.6856 4.3148

EO NEW 0.0000242425 2.40 -10.6274 0.8755

BD NEW 0.0000244394 35.50 -10.6193 3.5695

RE OLD 0.0000269514 5443.31 -10.5215 8.6021

BD NEW 0.0000298536 298.90 -10.4192 5.7001

EO NEW 0.0000301615 148.00 -10.4089 4.9972

EO NEW 0.0000330901 59.25 -10.3163 4.0818

BD NEW 0.0000336994 92.50 -10.2980 4.5272

BD NEW 0.0000354699 28.50 -10.2468 3.3499

RE OLD 0.0000378083 604.46 -10.1830 6.4043

EO NEW 0.0000382742 657.80 -10.1707 6.4889

EO NEW 0.0000383797 243.60 -10.1680 5.4955

RE OLD 0.0000387557 242.12 -10.1582 5.4894

EO NEW 0.0000387574 48.90 -10.1582 3.8898

BD NEW 0.0000407202 29.00 -10.1088 3.3673

BD NEW 0.0000415953 1349.80 -10.0875 7.2077

RE OLD 0.0000417925 42609.46 -10.0828 10.6598

BD NEW 0.0000429883 248.00 -10.0546 5.5134

BD NEW 0.0000443510 99.00 -10.0234 4.5951

BD NEW 0.0000462778 1.75 -9.9808 0.5596

RE OLD 0.0000470621 906.10 -9.9640 6.8091

RE OLD 0.0000482670 10833.21 -9.9388 9.2904

EO NEW 0.0000508340 79.00 -9.8869 4.3694

RE OLD 0.0000529921 890.55 -9.8454 6.7918

RE OLD 0.0000546755 1193.53 -9.8141 7.0847

EO NEW 0.0000561055 348.00 -9.7883 5.8522

EO NEW 0.0000569507 60.00 -9.7733 4.0943

EO NEW 0.0000626293 163.70 -9.6783 5.0980

RE OLD 0.0000626636 1985.67 -9.6777 7.5937

RE OLD 0.0000654535 318.60 -9.6342 5.7639

RE OLD 0.0000660567 5226.31 -9.6250 8.5615

RE OLD 0.0000664281 4914.24 -9.6194 8.4999

EO NEW 0.0000713497 343.00 -9.5479 5.8377

RE OLD 0.0000749810 1458.90 -9.4983 7.2854

EO NEW 0.0000778658 148.50 -9.4605 5.0006

BD NEW 0.0000893438 350.00 -9.3230 5.8579

BD NEW 0.0000936958 199.75 -9.2755 5.2971

BD NEW 0.0001029548 872.75 -9.1812 6.7716

EO NEW 0.0001063538 148.75 -9.1487 5.0023

BD NEW 0.0001147397 499.50 -9.0728 6.2136

RE OLD 0.0001266782 1183.21 -8.9739 7.0760

BD NEW 0.0001377292 73.00 -8.8902 4.2905

BD NEW 0.0001972580 174.75 -8.5310 5.1634

RE OLD 0.0002313295 50044.57 -8.3717 10.8207

B-33
Table B-1-1. Bagging data used to develop the correlation equations

----------------------- Equipment Type=VALVE Service=LL ------------------------

(continued)

Natural Natural

Log of Log of

Measured Emission Screening

Plant Data Emission Screening Rate Value Outlier

Type Origin Rate (kg/hr) Value (ppmv) (kg/hr) (ppmv) Flag

BD NEW 0.0002317965 180.00 -8.3697 5.1930

RE OLD 0.0002524777 12405.49 -8.2842 9.4259

RE OLD 0.0002580228 44328.29 -8.2625 10.6994

RE OLD 0.0002594664 510.60 -8.2569 6.2356

RE OLD 0.0002714139 185.88 -8.2119 5.2251

RE OLD 0.0002825941 6976.92 -8.1715 8.8504

RE OLD 0.0002947841 1516.43 -8.1293 7.3241

RE OLD 0.0003011106 44592.42 -8.1080 10.7053

RE OLD 0.0003056054 181.92 -8.0932 5.2036

RE OLD 0.0003367527 88.38 -7.9962 4.4816

RE OLD 0.0003494725 1041.01 -7.9591 6.9479

RE OLD 0.0003655199 17367.57 -7.9142 9.7624

RE OLD 0.0003726697 856.19 -7.8948 6.7525

RE OLD 0.0003738730 8088.28 -7.8916 8.9982

RE OLD 0.0003743390 1959.19 -7.8903 7.5803

RE OLD 0.0003964414 4048.28 -7.8330 8.3060

RE OLD 0.0004653107 35414.65 -7.6728 10.4749

BD NEW 0.0004698821 1543.75 -7.6630 7.3420

RE OLD 0.0004809845 4284.78 -7.6397 8.3628

RE OLD 0.0004922594 104088.32 -7.6165 11.5530

BD NEW 0.0005246367 2645.50 -7.5528 7.8806

RE OLD 0.0005251847 1151.37 -7.5518 7.0487

RE OLD 0.0005308943 14765.02 -7.5409 9.6000

RE OLD 0.0005614771 97.30 -7.4849 4.5778

BD NEW 0.0005705547 358.30 -7.4689 5.8814

RE OLD 0.0006267770 1565.55 -7.3749 7.3560

RE OLD 0.0006426108 5861.53 -7.3500 8.6762

RE OLD 0.0006597100 1793.09 -7.3237 7.4917

BD NEW 0.0006830173 94.75 -7.2890 4.5512

RE OLD 0.0007019466 8827.10 -7.2617 9.0856

RE OLD 0.0007129023 9940.79 -7.2462 9.2044

RE OLD 0.0007649183 25559.24 -7.1757 10.1488

RE OLD 0.0007702967 14.18 -7.1687 2.6518

RE OLD 0.0008350761 1281.36 -7.0880 7.1557

BD NEW 0.0008369235 6097.00 -7.0858 8.7156

RE OLD 0.0008536995 2810.09 -7.0659 7.9410

RE OLD 0.0008577230 6709.07 -7.0612 8.8112

RE OLD 0.0009616788 46673.57 -6.9468 10.7509

RE OLD 0.0010351161 71798.27 -6.8732 11.1816

RE OLD 0.0010736310 3136.03 -6.8367 8.0507

RE OLD 0.0012337497 8519.07 -6.6977 9.0501

RE OLD 0.0012793343 16658.85 -6.6614 9.7207

RE OLD 0.0013448227 962.89 -6.6115 6.8699

RE OLD 0.0013933013 1602.40 -6.5761 7.3793

B-34
Table B-1-1. Bagging data used to develop the correlation equations

----------------------- Equipment Type=VALVE Service=LL ------------------------

(continued)

Natural Natural

Log of Log of

Measured Emission Screening

Plant Data Emission Screening Rate Value Outlier

Type Origin Rate (kg/hr) Value (ppmv) (kg/hr) (ppmv) Flag

RE OLD 0.0014732045 22177.98 -6.5203 10.0069

RE OLD 0.0016009142 22172.87 -6.4372 10.0066

RE OLD 0.0018373887 1769.15 -6.2994 7.4783

RE OLD 0.0018697565 25877.90 -6.2819 10.1611

RE OLD 0.0021076721 93629.13 -6.1622 11.4471

RE OLD 0.0022196068 4376.80 -6.1104 8.3841

BD NEW 0.0023716142 1495.00 -6.0442 7.3099

RE OLD 0.0026041383 1313.08 -5.9507 7.1801

RE OLD 0.0026564280 52084.68 -5.9308 10.8606

RE OLD 0.0030068935 45068.90 -5.8068 10.7159

RE OLD 0.0030297587 6771.42 -5.7993 8.8205

RE OLD 0.0032025436 9836.80 -5.7438 9.1939

RE OLD 0.0032489277 140865.29 -5.7294 11.8556

RE OLD 0.0032868739 134149.17 -5.7178 11.8067

RE OLD 0.0034814651 284948.25 -5.6603 12.5601

RE OLD 0.0034830527 59618.63 -5.6598 10.9957

RE OLD 0.0035502018 4839.96 -5.6408 8.4847

RE OLD 0.0036059944 5555.74 -5.6252 8.6226

RE OLD 0.0037109239 72002.57 -5.5965 11.1845

RE OLD 0.0037115648 24755.46 -5.5963 10.1168

RE OLD 0.0038957946 9810.65 -5.5479 9.1912

BD NEW 0.0038969686 1544.40 -5.5476 7.3424

RE OLD 0.0039248950 7476.44 -5.5404 8.9195

RE OLD 0.0040089261 13953.59 -5.5192 9.5435

RE OLD 0.0042596218 30597.64 -5.4586 10.3287

RE OLD 0.0043498677 2026.05 -5.4376 7.6138

RE OLD 0.0043951332 4587.13 -5.4273 8.4310

RE OLD 0.0046094493 73036.68 -5.3796 11.1987

RE OLD 0.0046247477 2875.27 -5.3763 7.9639

RE OLD 0.0046555934 3279.62 -5.3697 8.0955

RE OLD 0.0047542941 5891.43 -5.3487 8.6813

RE OLD 0.0049436538 2135.71 -5.3097 7.6666

RE OLD 0.0049687260 9436.54 -5.3046 9.1523

RE OLD 0.0055770694 80485.19 -5.1891 11.2958

RE OLD 0.0059962681 19368.05 -5.1166 9.8714

RE OLD 0.0066867186 28552.82 -5.0076 10.2595

RE OLD 0.0073478291 129657.01 -4.9134 11.7726

RE OLD 0.0076182294 194.63 -4.8772 5.2711

RE OLD 0.0078722531 3118.82 -4.8444 8.0452

BD NEW 0.0079621021 9500.00 -4.8331 9.1590

RE OLD 0.0095095298 2553.37 -4.6555 7.8452

RE OLD 0.0102176741 44254.56 -4.5836 10.6977

RE OLD 0.0105761365 20652.95 -4.5492 9.9356

RE OLD 0.0126755860 960160.86 -4.3681 13.7749

B-35
Table B-1-1. Bagging data used to develop the correlation equations

----------------------- Equipment Type=VALVE Service=LL ------------------------

(continued)

Natural Natural

Log of Log of

Measured Emission Screening

Plant Data Emission Screening Rate Value Outlier

Type Origin Rate (kg/hr) Value (ppmv) (kg/hr) (ppmv) Flag

RE OLD 0.0128994159 301945.80 -4.3506 12.6180

RE OLD 0.0134752877 28558.21 -4.3069 10.2597

RE OLD 0.0137156706 114.30 -4.2892 4.7388

RE OLD 0.0190054451 1649.34 -3.9630 7.4081

RE OLD 0.0194889771 518201.90 -3.9379 13.1581

RE OLD 0.0220373843 213772.09 -3.8150 12.2727

RE OLD 0.0220386022 7980.81 -3.8150 8.9848

RE OLD 0.0221003955 362645.26 -3.8122 12.8012

RE OLD 0.0248459751 9843.83 -3.6951 9.1946

RE OLD 0.0254155227 41862.00 -3.6724 10.6421

RE OLD 0.0263386824 659517.01 -3.6367 13.3993

RE OLD 0.0272779071 1399.25 -3.6017 7.2437

RE OLD 0.0283621432 288.41 -3.5627 5.6644

RE OLD 0.0283930499 352.85 -3.5616 5.8660

RE OLD 0.0293848208 480.98 -3.5273 6.1758

RE OLD 0.0303470196 562236.45 -3.4951 13.2397

RE OLD 0.0305360632 21853.55 -3.4888 9.9921

RE OLD 0.0372725448 122666.22 -3.2895 11.7172

RE OLD 0.0410821388 62573.58 -3.1922 11.0441

RE OLD 0.0468639667 393961.70 -3.0605 12.8840

RE OLD 0.0687821973 49473.43 -2.6768 10.8092

RE OLD 0.0713743302 36751.32 -2.6398 10.5119

RE OLD 0.0838252864 360547.09 -2.4790 12.7954

RE OLD 0.1027415340 53569.80 -2.2755 10.8887

RE OLD 0.2448798474 371111.15 -1.4070 12.8243

N = 233 (1 outliers)

B-36
Table B-1-2. Comparison of regression results for the old, new, and

combined bagging data sets.

Equipment Type/Service: Connectors/All

Data Used in Regression

Statistical Parameter New

Number of data pairs 107

Regression intercept -14.815

Regression slope 0.885

Regression R2 0.525

Regression correlation coefficient 0.725

Regression mean square error 4.355

Regression root mean square error 2.087

Average ln screening value 3.472

Sum of squares of ln screening values 646.821

Scale bias correction factor 8.298

Correlation equation constant 3.05E-6

Equipment Type/Service: Pumps/Light Liquid

Data Used in Regression

Statistical Parameter Olda New Combined

Number of data pairs 51 68 117

Regression intercept -12.827 -12.515 -12.142

Regression slope 0.865 0.907 0.824

Regression R2 0.613 0.644 0.710

Regression correlation coefficient 0.783 0.803 0.842

Regression mean square error 2.246 3.783 2.591

Regression root mean square error 1.499 1.945 1.610

Average ln screening value 8.582 5.393 6.783

Sum of squares of ln screening values 233.223 548.793 1071.500

Scale bias correction factor 2.941 6.149 3.563

Correlation equation constant 7.91E-6 2.26E-5 1.90E-5

a Indicates that the parameter were derived from the

digitized data pairs for the OLD regression.

B-37
Table B-1-2. (continued)

Equipment Type/Service: Valves/Gas

Data Used in Regression

Statistical Parameter Olda New Combined

Number of data pairs 95 84 179

Regression intercept -12.848 -14.936 -15.033

Regression slope 0.661 0.750 0.873

Regression R2 0.359 0.516 0.715

Regression correlation coefficient 0.599 0.711 0.846

Regression mean square error 2.767 4.392 3.745

Regression root mean square error 1.663 2.096 1.935

Average ln screening value 8.823 3.691 6.415

Sum of squares of ln screening values 329.550 682.442 2186.020

Scale bias correction factor 3.858 8.311 6.315

Correlation equation constant 1.02E-5 2.71E-6 1.87E-6

a Indicates that the parameter were derived from the

digitized data pairs for the OLD regression.

Equipment Type/Service: Valves/Light Liquid

Data Used in Regression

Statistical Parameter Olda New Combined

Number of data pairs 126 107 232

Regression intercept -10.585 -14.137 -13.975

Regression slope 0.452 0.721 0.797

Regression R2 0.194 0.502 0.677

Regression correlation coefficient 0.441 0.709 0.823

Regression mean square error 4.413 3.115 4.088

Regression root mean square error 2.101 1.765 2.022

Average ln screening value 8.978 3.300 6.345

Sum of squares of ln screening values 644.683 633.647 3110.310

Scale bias correction factor 8.608 4.580 7.520

Correlation equation constant 2.18E-4 3.32E-6 6.41E-6

a indicates that the parameter were derived from the

digitized data pairs for the OLD regression

B-38
APPENDIX B: ATTACHMENT 2

This attachment lists the data used to develop the default-zero

emission leak rates in table B-2-1. Table B-2-2 lists summary

information on the default-zero development.

B-39
Table B-2-1. Data used for default zero calculations.

------------Equipment Type=CONNECTORS Service=ALL-------

Natural Log

Mass of Mass

Screening Emission Emission

PLT_TYPE Value (ppmv) Rate (kg/hr) Rate (kg/hr

EO 0.00 0.0000000475 -16.86331619

EO 0.00 0.0000000608 -16.61499543

EO 0.00 0.0000000613 -16.60715372

EO 0.00 0.0000000790 -16.35377339

EO 0.00 0.0000000988 -16.13056673

EO 0.00 0.0000001027 -16.09179287

BD 0.00 0.0000001033 -16.08517422

BD 0.00 0.0000001037 -16.08139097

EO 0.00 0.0000001065 -16.05508510

EO 0.00 0.0000001079 -16.04208307

EO 0.00 0.0000001085 -16.03689892

EO 0.00 0.0000001089 -16.03320436

EO 0.00 0.0000001112 -16.01231281

EO 0.00 0.0000001113 -16.01113856

EO 0.00 0.0000001115 -16.00911113

EO 0.00 0.0000001120 -16.00437388

EO 0.00 0.0000001125 -16.00075170

EO 0.00 0.0000001133 -15.99300732

EO 0.00 0.0000001146 -15.98221965

EO 0.00 0.0000001146 -15.98146212

EO 0.00 0.0000001150 -15.97834935

EO 0.00 0.0000001166 -15.96444127

EO 0.00 0.0000001176 -15.95559511

EO 0.00 0.0000001177 -15.95545662

EO 0.00 0.0000001178 -15.95391595

EO 0.00 0.0000001181 -15.95192362

EO 0.00 0.0000001189 -15.94478891

EO 0.00 0.0000001213 -15.92488652

EO 0.00 0.0000001234 -15.90745448

EO 0.00 0.0000001240 -15.90308275

EO 0.00 0.0000001296 -15.85882804

EO 0.00 0.0000001320 -15.84081663

BD 0.00 0.0000001349 -15.81855266

EO 0.00 0.0000001376 -15.79862472

EO 0.00 0.0000001390 -15.78899513

BD 0.00 0.0000001412 -15.77318199

EO 0.00 0.0000001413 -15.77244897

BD 0.00 0.0000001440 -15.75326730

BD 0.00 0.0000001446 -15.74929429

BD 0.00 0.0000001448 -15.74817023

BD 0.00 0.0000001454 -15.74382504

BD 0.00 0.0000001455 -15.74329360

BD 0.00 0.0000001485 -15.72271562

BD 0.00 0.0000001490 -15.71949421

BD 0.00 0.0000001497 -15.71483698

BD 0.00 0.0000001505 -15.70909501

B-40
Table B-2-1. Data used for default zero calculations.

-------- Equipment Type=CONNECTORS Service=ALL ---------

(continued)

Natural Log

Mass of Mass

Screening Emission Emission

PLT_TYPE Value (ppmv) Rate (kg/hr) Rate (kg/hr

EO 0.00 0.0000001511 -15.70514515

EO 0.00 0.0000001544 -15.68403336

BD 0.00 0.0000001547 -15.68204363

EO 0.00 0.0000001563 -15.67144879

BD 0.00 0.0000001573 -15.66508859

BD 0.00 0.0000001574 -15.66465227

BD 0.00 0.0000001596 -15.65073157

BD 0.00 0.0000001614 -15.63962500

BD 0.00 0.0000001621 -15.63500235

BD 0.00 0.0000001625 -15.63229582

EO 0.00 0.0000001631 -15.62914831

EO 0.00 0.0000001636 -15.62557049

EO 0.00 0.0000001641 -15.62273582

EO 0.00 0.0000001642 -15.62198449

EO 0.00 0.0000001648 -15.61837621

EO 0.00 0.0000001648 -15.61837621

EO 0.00 0.0000001650 -15.61705986

EO 0.00 0.0000001650 -15.61705962

EO 0.00 0.0000001651 -15.61656953

EO 0.00 0.0000001657 -15.61295101

EO 0.00 0.0000001657 -15.61295101

EO 0.00 0.0000001660 -15.61112981

EO 0.00 0.0000001688 -15.59463081

EO 0.00 0.0000001692 -15.59241662

EO 0.00 0.0000001717 -15.57752890

BD 0.00 0.0000001741 -15.56347827

BD 0.00 0.0000001747 -15.56001908

EO 0.00 0.0000001750 -15.55828552

EO 0.00 0.0000001807 -15.52620814

EO 0.00 0.0000001812 -15.52341721

BD 0.00 0.0000001904 -15.47417798

BD 0.00 0.0000001920 -15.46559058

BD 0.00 0.0000001932 -15.45958528

EO 0.00 0.0000001990 -15.43018880

EO 0.00 0.0000002086 -15.38283699

EO 0.00 0.0000002194 -15.33220908

EO 0.00 0.0000002431 -15.22964242

EO 0.00 0.0000002476 -15.21159451

EO 0.00 0.0000002508 -15.19874994

EO 0.00 0.0000002570 -15.17423032

BD 0.00 0.0000002585 -15.16823490

EO 0.00 0.0000002593 -15.16532554

BD 0.00 0.0000002594 -15.16500428

EO 0.00 0.0000002602 -15.16174131

EO 0.00 0.0000002607 -15.15994436

B-41
Table B-2-1. Data used for default zero calculations.

-------- Equipment Type=CONNECTORS Service=ALL ---------

(continued)

Natural Log

Mass of Mass

Screening Emission Emission

PLT_TYPE Value (ppmv) Rate (kg/hr) Rate (kg/hr

EO 0.00 0.0000002626 -15.15272411

EO 0.00 0.0000002626 -15.15272411

EO 0.00 0.0000002659 -15.13996186

EO 0.00 0.0000002664 -15.13812531

BD 0.00 0.0000002959 -15.03330632

EO 0.00 0.0000003055 -15.00115460

BD 0.00 0.0000003140 -14.97386313

EO 0.00 0.0000003276 -14.93133352

BD 0.00 0.0000003303 -14.92340849

BD 0.00 0.0000003315 -14.91955531

BD 0.00 0.0000003346 -14.91035517

BD 0.00 0.0000003436 -14.88372774

BD 0.00 0.0000003436 -14.88368692

BD 0.00 0.0000003442 -14.88192105

BD 0.00 0.0000003461 -14.87648133

BD 0.00 0.0000003504 -14.86410580

BD 0.00 0.0000003672 -14.81747447

BD 0.00 0.0000003946 -14.74527193

BD 0.00 0.0000004121 -14.70207785

EO 0.00 0.0000004133 -14.69904106

BD 0.00 0.0000004212 -14.68010001

EO 0.00 0.0000004468 -14.62113094

BD 0.00 0.0000004720 -14.56621062

EO 0.00 0.0000005089 -14.49108397

EO 0.00 0.0000005180 -14.47320006

EO 0.00 0.0000005187 -14.47197698

EO 0.00 0.0000005908 -14.34186784

EO 0.00 0.0000006166 -14.29899587

BD 0.00 0.0000006960 -14.17794549

EO 0.00 0.0000007110 -14.15652787

EO 0.00 0.0000007192 -14.14510177

EO 0.00 0.0000008267 -14.00581175

EO 0.00 0.0000009572 -13.85929011

EO 0.00 0.0000010002 -13.81535039

BD 0.00 0.0000010065 -13.80901606

EO 0.00 0.0000010071 -13.80841513

EO 0.00 0.0000011795 -13.65045667

EO 0.00 0.0000011927 -13.63931593

EO 0.00 0.0000021315 -13.05868377

BD 0.00 0.0000023492 -12.96141917

EO 0.00 0.0000024557 -12.91711588

BD 0.00 0.0000024895 -12.90342759

BD 0.00 0.0000025620 -12.87473675

BD 0.00 0.0000030901 -12.68731235

BD 0.00 0.0000033269 -12.61346713

B-42
Table B-2-1. Data used for default zero calculations.

--------- Equipment Type=CONNECTORS Service=ALL --------

(continued)

Natural Log

Mass of Mass

Screening Emission Emission

PLT_TYPE Value (ppmv) Rate (kg/hr) Rate (kg/hr

BD 0.00 0.0000037589 -12.49138454

BD 0.00 0.0000040185 -12.42460572

BD 0.00 0.0000042414 -12.37062573

BD 0.00 0.0000044626 -12.31978282

BD 0.00 0.0000066833 -11.91589131

BD 0.00 0.0000075709 -11.79119727

BD 0.00 0.0000105577 -11.45865639

BD 0.00 0.0000144776 -11.14290744

BD 0.00 0.0000154005 -11.08111125

BD 0.00 0.0000165494 -11.00916328

N = 146

------------------- Equipment Type=PUMP Service=LL

-------------------

Natural Log

Mass of Mass

Screening Emission Emission

PLT_TYPE Value (ppmv) Rate (kg/hr) Rate (kg/hr

EO 0.00 0.0000002532 -15.18920187

EO 0.00 0.0000002674 -15.13444207

BD 0.00 0.0000003397 -14.89520337

BD 0.00 0.0000006493 -14.24738145

BD 0.00 0.0000013801 -13.49334976

BD 0.00 0.0000031715 -12.66130995

EO 0.00 0.0000061497 -11.99910617

BD 0.00 0.0000978267 -9.232313175

N=8

B-43
Table B-2-1. Data used for default zero calculations.

----------- Equipment Type=VALVE Service=G -------------

Natural Log

Mass of Mass

Screening Emission Emission

PLT_TYPE Value (ppmv) Rate (kg/hr) Rate (kg/hr

EO 0.00 0.0000000591 -16.64400086

EO 0.00 0.0000000722 -16.44327301

EO 0.00 0.0000000737 -16.42283692

EO 0.00 0.0000000786 -16.35920326

EO 0.00 0.0000000790 -16.35376554

EO 0.00 0.0000000796 -16.34647953

EO 0.00 0.0000001079 -16.04237697

EO 0.00 0.0000001081 -16.04053084

EO 0.00 0.0000001083 -16.03863245

EO 0.00 0.0000001312 -15.84631356

EO 0.00 0.0000001321 -15.83996505

EO 0.00 0.0000001325 -15.83639998

BD 0.00 0.0000001382 -15.79429751

BD 0.00 0.0000001436 -15.75651804

EO 0.00 0.0000001446 -15.74956966

BD 0.00 0.0000001516 -15.70207714

EO 0.00 0.0000001581 -15.65972752

BD 0.00 0.0000001595 -15.65122577

BD 0.00 0.0000001602 -15.64710329

EO 0.00 0.0000001750 -15.55828552

EO 0.00 0.0000002350 -15.26347692

BD 0.00 0.0000002539 -15.18638489

EO 0.00 0.0000002612 -15.15814418

BD 0.00 0.0000002633 -15.14979281

EO 0.00 0.0000002674 -15.13444207

BD 0.00 0.0000003272 -14.93266093

BD 0.00 0.0000003339 -14.91228255

EO 0.00 0.0000003878 -14.76283680

EO 0.00 0.0000004091 -14.70928502

BD 0.00 0.0000004607 -14.59056027

EO 0.00 0.0000006457 -14.25286952

BD 0.00 0.0000007014 -14.17014032

EO 0.00 0.0000009932 -13.82235860

BD 0.00 0.0000009955 -13.81999480

BD 0.00 0.0000022122 -13.02153380

BD 0.00 0.0000022562 -13.00184573

BD 0.00 0.0000025712 -12.87114036

BD 0.00 0.0000033699 -12.60062417

BD 0.00 0.0000044219 -12.32894306

BD 0.00 0.0000106176 -11.45299698

N = 40

B-44
Table B-2-1. Data used for default zero calculations.

---------- Equipment Type=VALVE Service=LL -------------

Natural Log

Mass of Mass

Screening Emission Emission

PLT_TYPE Value (ppmv) Rate (kg/hr) Rate (kg/hr

EO 0.00 0.0000001121 -16.00352165

EO 0.00 0.0000001173 -15.95857877

EO 0.00 0.0000001211 -15.92634574

EO 0.00 0.0000001229 -15.91229458

EO 0.00 0.0000001337 -15.82756192

BD 0.00 0.0000001440 -15.75311308

BD 0.00 0.0000001461 -15.73913742

BD 0.00 0.0000001498 -15.71376221

BD 0.00 0.0000001503 -15.71042334

BD 0.00 0.0000001513 -15.70424314

EO 0.00 0.0000001642 -15.62246991

EO 0.00 0.0000001644 -15.62066973

EO 0.00 0.0000001644 -15.62066973

EO 0.00 0.0000001645 -15.62017964

EO 0.00 0.0000001648 -15.61837621

EO 0.00 0.0000001654 -15.61475957

EO 0.00 0.0000001656 -15.61343643

EO 0.00 0.0000001657 -15.61294634

EO 0.00 0.0000001660 -15.61112981

EO 0.00 0.0000001663 -15.60930997

BD 0.00 0.0000001669 -15.60596798

EO 0.00 0.0000001758 -15.55382679

EO 0.00 0.0000001758 -15.55382679

BD 0.00 0.0000001780 -15.54144504

BD 0.00 0.0000001804 -15.52802656

EO 0.00 0.0000001827 -15.51543605

BD 0.00 0.0000001853 -15.50155175

EO 0.00 0.0000002507 -15.19885548

EO 0.00 0.0000002568 -15.17511567

EO 0.00 0.0000002623 -15.15362868

EO 0.00 0.0000002645 -15.14545135

EO 0.00 0.0000002654 -15.14208066

EO 0.00 0.0000002657 -15.14094135

EO 0.00 0.0000002664 -15.13812531

EO 0.00 0.0000002750 -15.10635430

BD 0.00 0.0000002786 -15.09348218

BD 0.00 0.0000002807 -15.08603323

BD 0.00 0.0000002831 -15.07737541

BD 0.00 0.0000003292 -14.92670035

BD 0.00 0.0000003296 -14.92525863

BD 0.00 0.0000003327 -14.91592554

EO 0.00 0.0000003803 -14.78222371

EO 0.00 0.0000003997 -14.73266021

EO 0.00 0.0000004350 -14.64784669

EO 0.00 0.0000004933 -14.52205744

BD 0.00 0.0000005121 -14.48467228

B-45
Table B-2-1. Data used for default zero calculations.

------------ Equipment Type=VALVE Service=LL ------------

(continued)

Natural Log

Mass of Mass

Screening Emission Emission

PLT_TYPE Value (ppmv) Rate (kg/hr) Rate (kg/hr

EO 0.00 0.0000007099 -14.15820731

BD 0.00 0.0000011219 -13.70046348

BD 0.00 0.0000022380 -13.00992148

EO 0.00 0.0000028444 -12.77016392

BD 0.00 0.0000041389 -12.39507152

BD 0.00 0.0000053490 -12.13860411

EO 0.00 0.0000121637 -11.31705756

N = 53

B-46
Table B-2-2. Comparison of Default Zero Mass Emission Rates from the Original EPA Protocol and from the CMA/EPA E

Results from CMA/EPA EO/BD Bagging Data Study

Old Revised Default Zero

Default Zero Scale Bias Default Zero Lower 95% Upper 95% Screeni

Equipment Emission Rate Number of Correction Emission Rate Confidence Confidence Value

Type Service (kg/hr) Observations Factor (kg/hr) Limit Limit (ppmv)

CONNEC ALL 9.34E-5 146 2.06 6.12E-7 5.02E-7 7.45E-7 0.163

PUMP LL 3.91E-5 8 4.73 7.49E-6 1.36E-6 4.11E-5 0.323VALVE G 3.31E-5 40 2.19 6.56E-7 4.35E-7 9.87E-7 0.301VALVE LL 4.52E-4 53 1.65 4.85E-7 3.67E-7 6.42E-7 0.039

a The "default zero" screening value is the screening value that would result in emissions equal to

the default zero mass emission rate when entered into the applicable correlation. The revised SOCMI correlationswere used to estimate the "default zero" screening values.

B-47
APPENDIX B: ATTACHMENT 3

This attachment summarizes information on each of the

screening data sets. Table B-3-1 summarizes data used to revise

the SOCMI emission factors. Figures B-3-1 through B-3-4 plot the

screening value distributions for each data set.

B-48
Figure B-3-1. Distribution of Connectors Screening Values for

SOCMI

B-49
Figure B-3-2. Distribution of Light Liquid Pumps Screening

Values for SOCMI

B-50
Figure B-3-3. Distributio of Gas Valves Screening Values for

SOCMI

B-51
Figure B-3-4. Distribution of Light Liquid Valves Screening

Values for SOCMI

B-52
Table B-3-1. Emission Factors Calculated From Revised SOCMI

Correlation Equations.

Average Default

Old Total nonzero Number of zero Average

emission number of emission zero emission emission

Screening Equipment factor screening rate screening rate factor

data set type Phase (kg/hr) values (kg/hr) values (kg/hr) (kg/hr)

24 UNIT CONNEC ALL 8.30E-04 4,283 2.50E-02 3,740 6.12E-07 3.16E-03

24 UNIT PUMP LL 4.94E-02 646 5.36E-02 335 7.45E-06 2.58E-02

24 UNIT VALVE G 5.60E-03 9,669 2.47E-02 5,962 6.56E-07 9.45E-03

24 UNIT VALVE LL 7.10E-03 18,300 2.99E-02 14,292 4.85E-07 6.55E-03

EO/BD CONNEC ALL 8.30E-04 3,562 3.76E-04 1,381 6.12E-07 2.30E-04

EO/BD PUMP LL 4.94E-02 252 7.12E-03 85 7.45E-06 4.72E-03

EO/BD VALVE G 5.60E-03 6,507 2.83E-03 4,685 6.56E-07 7.92E-04

EO/BD VALVE LL 7.10E-03 15,810 3.26E-03 10,429 4.85E-07 1.11E-03

COMBINED CONNEC ALL 8.30E-04 7,845 5.28E-03 5,121 6.12E-07 1.83E-03a

COMBINED PUMP LL 4.94E-02 898 3.73E-02 420 7.45E-06 1.99E-02a

COMBINED VALVE G 5.60E-03 16,176 1.75E-02 10,647 6.56E-07 5.97E-03a

COMBINED VALVE LL 7.10E-03 34,110 1.46E-02 24,721 4.85E-07 4.03E-03a

a These average emission factors are the revised SOCMI average emission factors.

B-53
APPENDIX C:

Revision of Petroleum Industry Correlations and Emisison Factors
APPENDIX C

The purpose of this appendix is to provide background

information on the data collection and analysis performed to

revise the petroleum industry (refineries, marketing terminals,

and oil and gas production operations) correlations and to

develop marketing terminal and oil and gas production operation

average emission factors. Section C.1 addresses the following:

• Comparison of old (1980) and new (1993) refinery data;

• Development of revised petroleum industry correlation

equations, default zero emission rates, and pegged

emission rates;

• Summary of petroleum industry correlation parameters;

and

• Development of marketing terminal and oil and gas

production operation average emission factors.

The figures for this section appear at the end of section C.1.

Several attachments that list all of the data are also

included for this appendix. Attachment 1 lists the bagging data

used to develop the correlation equations, attachment 2 lists the

bagging data used to develop pegged emission rates, attachment 3

lists the bagging data used to develop default zero emission

rates, and attachment 4 summarizes the screening data for average

emission factors.

C.1 DEVELOPMENT OF REVISED PETROLEUM INDUSTRY CORRELATIONS AND

FACTORS

During the early-1990’s, new petroleum industry equipment

leak data were collected and analyzed. The Western States

Petroleum Association (WSPA) and the American Petroleum Institute

(API) jointly commissioned the 1994 refinery equipment leak

report1 to evaluate fugitive emissions at petroleum refineries.

The API also commissioned the 1993 marketing terminal equipment

leak report,2 and, along with the Gas Research Institute (GRI),

jointly commissioned the 1993 oil and gas production operations

reports.3,4 These data are referred to in this discussion as the

1993 petroleum industry data. In contrast to the data collected

during the late-1970’s for the 1980 refinery report5 (these are

referred to in this discussion as the 1980 refinery data) which

came from uncontrolled facilities and were used to develop

correlations and emission factors that appear in previous

C-1
versions of this protocol, the 1993 petroleum industry data came

from controlled facilities and were collected using current

procedures that are considered state of the art for the 1990’s.

The purpose of this section is to explain how and why the

1993 data were used to update the petroleum industry correlations

and to present the data that were used in this update. The

conclusions presented in this section were based on a combination

of engineering judgement and quantitative statistical analysis of

the available emission data. Judgments were made based on an

understanding of possible mechanisms of equipment leak emissions

and qualitative assessment of the data. A more detailed

explanation of the analyses highlighted in this section appear in

a technical memorandum6 that is available on EPA’s electronic

bulletin board.7

C.1.1 Overview of Data Analysis

Based on guidelines presented in chapter 4 of this document,

the quality control/quality assurance (QC/QA) procedures for data

collection and laboratory analysis of the 1993 petroleum industry

data were evaluated and found to be of sufficient quality for the

development of correlations. However, a few data pairs were

excluded from correlation development due to large background

concentrations or high screening value variability. Several

options were considered for using the 1993 petroleum industry

equipment leak data, including:

• Combine the 1980 refinery data and the 1993 refinery data to

develop revised refinery correlations and, based on 1993

data, provide separate new correlations for marketing

terminals and oil and gas production operations.

• Combine the 1980 refinery data with the 1993 refinery,

marketing terminal, and oil and gas production data to

develop new petroleum industry correlations that apply to

all three industry segments.

• Drop the 1980 data and correlations from further use.

Combine the 1993 refinery, marketing terminal, and oil and

gas production operations data to develop a single

correlation that applies to all three industry segments or

keep the three industry segment correlations separate.

C-2
Judgments based upon an understanding of equipment leak

emission mechanisms and a qualitative assessment of the data were

used in conjunction with the following visual comparisons and

statistical tests, that quantitatively evaluate the similarities

or differences between the data being compared, to assess the

options listed above:

• Visual comparison of the plotted data, regression lines, and

95 percent confidence intervals for the regression lines, to

identify general characteristics of the data and to put the

results of statistical tests into perspective.

• F-test for the mean square error (MSE) differences between

the regression equations, to compare the variability of the

errors of the predictions.

• T-tests for intercept (b0) and slope (b1) differences

between the regression equations, to determine whether the

regressions were statistically different. If the t-test for

the intercepts indicated similarities, but the t-test for

the slopes indicated differences or vice versa, the

regressions were considered statistically different.

However, when both the intercept and slope t-tests indicated

similarities, the regressions were considered statistically

the same.

• Mass verification analysis. Because of the statistical

requirement for normality of the data distributions for the

above tests to be valid, the visual and statistical tests

were evaluated in log-log space (i.e., the mathematical

space that results when regressing the natural logarithm of

the mass emission rate against the natural logarithm of the

screening value). The mass verification analysis was

conducted to assess the impact of the correlations on the

nontransformed data. The total measured mass was compared

to the total mass predicted from each of the industry

segment correlations and from the combined correlations.

Mass ratios (the ratio of the total predicted mass to the

total measured mass) formed the basis for evaluating the

results. The mass verification was considered good when

mass ratio was close to 1.0, indicating that the predicted

mass was close to the measured mass (a mass ratio of 1.0

indicates a perfect prediction because the predicted mass

equals the measured mass).

C-3
C.1.2 Comparison of the 1993 Refinery Data with the 1980

Refinery Data

The 1980 refinery data were collected and analyzed in the

laboratory using procedures that were not as stringent as the

current procedures. Thus, the 1993 refinery data are of better

quality than the 1980 data, as evaluated by today’s standards.

Also, the 1980 data were screened with a TLV calibrated with

hexane and the 1993 refinery data were screened with an OVA

calibrated with methane. Thus, any comparisons between the two

datasets must be made on a common basis. The conversion from TLV

to OVA is not totally clear or understood. Multiple conversion

equations exist and the TLV/OVA relationship changes at different

screening levels. Also, the TLV and OVA use different methods to

obtain measurements that give different results for the same

data. This difficulty was overcome sufficiently to perform a

crude comparison; however no adjustments could be made to compare

both datasets on a common basis with regards to data quality.

The following relationship (taken from Figure C3-18a)8 was used

to approximate an OVA-methane screening value from a TLV-hexane

screening value:

SVOVA-methane = 10C (C-1)

where:

SVOVA-methane = screening value taken with OVA-methane

C =

[log10(SVTLV-hexane) + 0.193]

0.952

SVTLV-hexane = screening value taken with TLV-hexane.

However, this transformation was achieved in the 1993

refinery report1 using another conversion equation (from the 1979

valve screening report9) that gave results that were different

from those obtained using Equation C-1 above, thereby emphasizing

the uncertainty that exists for any of the transformations from

TLV to OVA.

Additionally, pegged data were identified in the 1980

dataset and removed prior to comparisons with the 1993 refinery

C-4
data, because separate emission rates are now calculated for

pegged readings. Thus, the 1980 correlations were adjusted for

screening instrument (TLV) and pegged data. Using available

screening data from 17 marketing terminals as an example, the

adjusted 1980 correlations gave estimations of total facility

emissions that ranged between 42% to 116% of the total facility

emissions obtained from the published 1980 correlations. The

adjusted 1980 correlations gave an estimation of the total

emissions from all 17 marketing terminals that were 61% of the

total emissions estimated from the published 1980 correlations.

The comparisons between the 1980 refinery data and the 1993

refinery data were made for matching equipment types/services.

The following four equipment types/services were compared: all

connectors, light liquid pumps, gas valves, and light liquid

valves. Plots that compare the raw data, the regression lines,

and the 95 percent confidence intervals of the regression lines

for the 1980 and 1993 refinery data were constructed for the four

equipment types/services. The plot for all connector data, which

illustrates the largest visual differences, is shown in

Figure C-1 and the plot for gas valve data, which illustrates the

smallest visual differences, is shown in figure c-2. All of the

plots revealed a general separation of data pairs and 95 percent

confidence intervals of the regression lines, thereby suggesting

that there were differences between the 1980 and 1993 refinery

data.

The results of the statistical tests (not shown) for

differences between the 1980 and 1993 refinery regressions

indicated that the regression lines were different because

statistically significant differences between the 1980 refinery

data and the 1993 refinery data existed for both the slope and

intercept for all equipment types/services. Figure C-3 shows the

ratios of predicted to measured mass that were calculated from

the 1980 refinery data, the 1993 refinery data, and the combined

1980/1993 refinery data (a predicted to measured mass ratio of

1.0 would indicate a perfect prediction). In all cases, either

the combined correlation or the 1993 refinery correlation did a

C-5
better job of predicting the total mass of the 1980 refinery data

than did the 1980 correlation, and the 1993 refinery correlation

always gave the best mass ratios for the 1993 refinery data. The

ratios of predicted to measured mass using the combined 1980/1993

refinery correlations were further from 1.0 than those obtained

individually with either the 1980 or 1993 refinery correlations

for the respective datasets, and thus, a rather poor verification

of the combined correlation was indicated.

Based on the above results, the 1980 refinery data were not

used to develop the revised correlations that are presented in

this revised version of the protocol.

C.1.3 Comparison of the 1993 Refinery Data, the 1993

Marketing Terminal Data, and the 1993 Oil and Gas

Production Operations Data

An underlying concern with all of the comparisons discussed

in this section was the relatively small sample size for most of

the equipment types/services. This problem was also encountered

in the 1980 refinery report.5 Table C-1 shows the sample size

for each equipment type/service for the 1993 refinery data, the

1993 marketing terminal data, and the 1993 oil and gas production

operations data that were deemed suitable for correlation

development. (For comparative purposes, the corresponding sample

sizes from the 1980 refinery analysis5 are footnoted in

Table C-1.) The sample size was 30 or larger for only 9 of the

46 equipment types/services for which data were collected. It is

recommended in chapter 2 that the sample size should be 30 or

larger for the development of correlations. In addition, the

sample size was 10 or less for 23 of the 46 equipment

types/services. Sample sizes that are this small may produce

results of only limited usefulness and meaning.

Two-way statistical comparisons were made between the 1993

refinery, marketing terminal, and oil and gas production

operations data for equipment types/services where data were

collected. All comparisons were service-specific. The following

equipment types/services were compared: light liquid connectors,

light liquid flanges, light liquid open-ended lines, light liquid

C-6
TABLE C-1. SUMMARY OF THE SAMPLE SIZE FOR EACH EQUIPMENT

TYPE/SERVICE FOR THE 1993 REFINERY DATA, THE 1993 MARKETING

TERMINAL DATA, AND THE 1993 OIL AND GAS PRODUCTION OPERATIONS

DATA

Equipment

Type

Stream

Service

Sample Size

Total

1993

Refinery

Data

1993

Marketing

Terminal

Data

1993 Oil &

Gas

Production

Operations

Data

Connector Gas

Heavy Liquid

Light Liquid

8

2

18

2

0

21

24

1

42

34

3

81

Flange Gas

Heavy Liquid

Light Liquid

4

1

15

1

0

12

9

1

13

14

2

40

Instrumenta Gas

Light Liquid

0

0

0

0

2

1

2

1

Loading

Arma

Gas

Light Liquid

0

0

7

16

0

0

7

16

Open-Ended

Line

Gas

Heavy Liquid

Light Liquid

7

3

15

0

0

16

48

13

39

55

16

70

Othera Gas

Light Liquid

0

0

1

3

0

0

1

1

Pressure

Relief

Valvea

Gas

Light Liquid

1

1

0

0

6

3

7

4

Pump Heavy Liquid

Light Liquid

11

30

0

11

0

1

11

42

Stuffing

Boxa

Heavy Liquid

Light Liquid

0

0

0

0

11

12

11

12

Valve Gas

Heavy Liquid

Light Liquid

50

22

82

2

0

45

84

1

51

136

23

178

Venta Gas

Light Liquid

0

0

0

0

3

3

3

3

1993 Petroleum Industry

Total 270 137 368 775

1980 Refinery Totalb 678

a Components with small sample sizes will be grouped together

to form an "OTHERS" category. b For comparative purposes, sample sizes from the 1980

refinery report are: all flanges-52; light liquid

pumps-259, gas valves-79; light liquid values-119; valves

and compressors in hydrogen service-47; all drains-61; and

heavy liquid pumps-61.

C-7
pumps, gas valves, and light liquid valves.

Plots that compare the 1993 refinery, marketing terminal,

and oil and gas production operations raw data, regression lines,

and 95 percent confidence intervals for the regression lines were

constructed for all equipment types/services listed above. The

plot for light liquid flange data, which illustrates the largest

visual differences, is shown in Figure C-4 and the plot for light

liquid valve data, which illustrates the smallest visual

differences, is shown in Figure C-5. In general, all of the data

plots revealed a general intermingling of data pairs from the

three petroleum industry segments and an overlapping of 95

percent confidence intervals of the regression lines. No clear

separation of petroleum industry segments was evident in most of

the data plots.

The results of the statistical tests (not shown) for two-way

differences between regressions for the petroleum industry

segment datasets indicated statistically significant differences

for all of the equipment types/services; however, the visual

plots indicated that these differences may be too small to really

be relevant, especially when compared to the magnitude of the

differences between the 1980 and 1993 refinery data.

Figure C-6 presents the ratios of predicted to measured mass

that were calculated from the 1993 refinery, marketing terminal,

and oil and gas production operations data. The mass ratios from

facility type-specific correlations for the predictions that were

closest to 1.0 for a given facility type dataset were usually

from the correlation based on another facility type. For

example, for light liquid valves, the marketing terminal

correlation gave a mass ratio of 1.06 for the refinery data,

whereas the refinery correlation gave a mass ratio of 1.50 for

the refinery data.

In several cases, the combined petroleum industry

correlation gave an even closer ratio of predicted to measured

mass than any of the individual facility type-specific

correlations. For example, for light liquid flanges, the

combined correlation gave a mass ratio of 0.94 for the marketing

C-8
terminal data, which is better than the 1.34 obtained when using

the marketing terminal correlation. Overall, the combined 1993

petroleum industry correlations gave mass ratios ranging between

0.10 and 2.85 for facility type-specific datasets. The mass

ratios using the combined correlations to predict the total mass

of the combined dataset ranged between 0.28 and 1.42 for all

equipment types/services. Thus, the ratios of predicted to

measured mass obtained from the combined 1993 petroleum industry

correlations were closer to 1.0 than those obtained individually

with facility type-specific correlations, thus supporting the

combination of data from the three petroleum industry segments.

It is not surprising that the visual and statistical results

showed similarities between the petroleum industry segment

datasets because the three industry segments produce similar

products of similar molecular weights, viscosities, and

densities. Therefore the leak mechanisms and screening

instrument response rates are not expected to be different

between the industry segments. Although some small differences

were identified, there is not compelling evidence to believe that

these differences were large enough to be real or meaningful.

C.1.4 Development of the Combined Refinery/Marketing

Terminal/Oil and Gas Production Pperations

Correlations, Default Zero Emission Rates, and Pegged

Emission Rates

Based on the results presented in the above section, the

1993 refinery, marketing terminal data, and oil and gas

production operations data were combined to develop petroleum

industry correlations using the procedures outlined in chapter 2

and appendix B. Due to the small sample size for some equipment

types, an "others" category was developed to provide a

correlation for cases not otherwise covered. The equipment types

flagged in Table C-1 (instruments, loading arms, other, pressure

relief valves, stuffing boxes, and vents, compressors, and dump

lever arms) were combined to form this "other" equipment type.

The visual and statistical tests for differences between

regression equations were applied to the combined dataset to aid

in the decision of what equipment type(s)/service(s), if any, to

C-9
combine for developing the correlations. Visual inspection of

the data plots (not shown) revealed that the gas, light liquid,

and heavy liquid service data were generally well intermingled.

The p-values from the t-tests for b0 and b1 differences indicated

that the services were statistically similar only for gas/heavy

liquid open-ended lines and for gas/light liquid open-ended

lines. However, most of the statistically significant

differences appeared too small in the visual plots to really be

relevant. As with the comparisons between the refinery,

marketing terminal, and oil and gas production operations data,

the mass verification analysis for the services showed that when

differences were identified for the service comparisons, they

were small, thereby lending support towards combining the data.

Other factors that support combining services include:

• The leak mechanism is the same regardless of service.

However, screening value distributions, which affect total

emissions (not correlations), may be different for each

service.

• When services were segregated, sample sizes for nearly all

equipment types were less than 30, the sample size

recommended in chapter 2 for developing correlations, even

after combining all of the petroleum industry segment data.

Combination of data from all services increased the sample

size to above 30 for nearly all equipment types.

• The importance of the component service was investigated in

the 1994 refinery report,1 using additional statistical

tests. The analyses of variance that were presented in the

refinery report showed that services should be combined

because there were no statistically significant differences

between the correlations for different services for a given

equipment type.

The visual analysis that was conducted to compare the

regression equations for the different equipment types revealed

that the raw data for the different equipment types were well

intermingled for some equipment types and separated for other

types. However, a stacking of regression lines and confidence

intervals was evident, such that some equations overlapped

(connectors and open-ended lines), but there were rather large

differences between other equations (pumps versus connectors).

Thus, in contrast to other comparisons, where the differences

C-10
were either consistently large (1980 versus 1993 refinery data)

or small (1993 petroleum industry segment data), differences

between the equipment types varied. Based on the visual results,

it was felt that further analysis outside the objectives of this

study was necessary to determine which equipment types to

combine. Therefore, the equipment types remained segregated.

Correlations, default zero emission rates, and pegged

emission rates were developed from the combined 1993 refinery,

marketing terminal, and oil and gas production operations data

for combined services for connectors, flanges, open-ended lines,

pumps, valves, and "other" equipment types. Table C-2 shows the

regression statistics for correlations. The R2 values ranged

from 0.32 for "others" to 0.54 for valves, thereby indicating

that the equations were capable of predicting about half of the

variability of the mass emission rates. These R2 values

corresponded to correlation coefficients (r, the square root of

R2) ranging from 0.57 to 0.73. Although these R2 values were

sometimes less than those obtained for individual

facility/service types, they were more consistent across

equipment types than the R2 values for the individual

facility/service types which ranged from 0.04 to 0.75. These R2

values revealed the inherent limits of this tool for predicting

mass emission rates (an inability to account for 25% to 50% of

the mass emission variance) and were not substantially different

from those shown in other reports.1,2,3,5 Table C-3 shows the

petroleum industry correlations, default zero emission rates, and

pegged emission rates for each equipment type as calculated from

the combined 1993 refinery, marketing terminal, and oil and gas

production operations data.

Emission estimates from the revised correlations depend on

the distribution of equipment types and screening values at a

given facility. Comparisons of the results obtained from the

1993 correlations and previously published correlations can vary

greatly from facility-to-facility. For screening data that

contained a large number of low screening values from 17

marketing terminals, the 1993 correlations gave estimations of

C-11
TABLE C-2. REGRESSION STATISTICS FOR THE COMBINED 1993 REFINERY, MARKETI

AND OIL AND GAS PRODUCTION OPERATIONS DATA

Equipment Type/

Service

Number

of Data

Pairs

Intercept

(b0)

Slope

(b1)

Coefficient

of Simple

Determinati

on (R2)

Standard

Error of

Estimate

Mean ln

Screening

Valuea

Sum of

Squared

Differences b

Scale Bias

Correction

Factor

(SBCF)

Valve/All 337 -14.169 0.746 0.54 1.544 6.477 1705.07 3.27 

Connector/All 118 -14.893 0.735 0.47 1.754 6.214 592.09 4.51 

Pump/All 53 -11.546 0.610 0.46 1.856 5.816 409.21 5.15 

Otherd/All 70 -12.838 0.589 0.32 1.843 5.437 316.36 5.14 

Flange/All 56 -13.788 0.703 0.37 1.771 5.767 204.71 4.48 

Open-Ended Line/All 141 -14.658 0.704 0.44 1.823 6.166 745.97 5.11 

aThe mean ln screening value is the average of all of the ln screening val

X_

= (1/n)×

Σ(Xi).

bThe sum of squared differences refers to the difference between the indiv

screening values and the average ln screening value:

Σ(Xi-X

_

)2. (The mea

screening value and the sum of squared differences are used to calculate intervals.)

cThe half-width of the 95 percent confidence interval is calculated using 

screening value as the X-value being evaluated in the confidence intervalcalculation.

dThe "other" equipment type includes instruments, loading arms, pressure r

valves,

stuffing boxes, vents, compressors, and dump lever arms.

C-12
TABLE C-3. CORRELATION EQUATIONS, DEFAULT ZERO EMISSION RATES, AND PEGG

RATES FOR PREDICTING TOTAL ORGANIC COMPOUND EMISSIONS FROM THE COMBINED 1

MARKETING TERMINAL, AND OIL AND GAS PRODUCTION OPERATIONS DATA

Equipment Type/Service Default Zero Emission Rate (kg/hr/source)b Pegged Emission Rates (kg/hr/source)c Correla

(kg/

10,000 ppmv 100,000 ppmv

Valve/All 7.8E-06 0.064 0.140 LEAK = 2.

Pump/All 2.4E-05 0.074 0.160e LEAK = 5.

Otherf/All 4.0E-06 0.073 0.110 LEAK = 1.

Connector/All 7.5E-06 0.028 0.030 LEAK = 1.

Flange/All 3.1E-07 0.085 0.084 LEAK = 4.

Open-Ended Line/All 2.0E-06 0.030 0.079 LEAK = 2.

aTo estimate emissions: use the default zero emission rates only when the screening value 

background) equals 0.0 ppmv; otherwise use the correlation equations. If the monitorinregisters a pegged value, use the appropriate pegged emission rate.

bDefault zero emission rates were based on the combined 1993 refinery and marketing termi

(default zero data were not collected from oil and gas production facilities).

cThe 10,000 ppmv pegged emission rate was based on components screened at greater than 10

however, in some cases, most of the data could have come from components screened at gr100,000 ppmv, thereby resulting in similar pegged emission rates for both the 10,000 anlevels (e.g., connector and flanges).

dLEAK is the predicted mass emission rate (kg/hr) and SV is the screening value (ppmv) me

monitoring device.

eOnly 2 data points were available for the pump 100,000 pegged emission rate; therefore t

the pump 10,000 pegged emission rate to the overall 10,000 ppmv pegged emission rate wathe overall 100,000 ppmv pegged emission rate to approximate the pump 100,000 ppmv peggrate.

fThe "other" equipment type was developed from instruments, loading arms, pressure relief 

stuffing boxes, vents, compressors, dump lever arms, diaphrams, drains, hatches, metersrods. This "other" equipment type sould be applied to any equipment other than connectopen-ended lines, pumps or valves.

C-13
the total facility emissions that ranged from less than 10% to

over 800% of the total facility emissions obtained from the

adjusted 1980 correlations presented in this paper. When the

total emissions from all 17 marketing terminals were evaluated,

the 1993 correlations gave an estimate that was 40% of the total

estimated by the adjusted 1980 correlations. Though the 17

marketing terminals do not represent the entire petroleum

industry, these results illustrate the differences encountered

when comparing emission estimates for individual facilities

versus evaluating all facilities as a single group.

C.1.4 Marketing Terminal and Oil and Gas Production Operation

Screening Data for Development of Average Emission

Factors

Screening data from 17 marketing terminals10 and from 24 oil

and gas production operation facilities11,12 were available to

EPA for the development of average emission factors using the

same procedures as discussed in appendix B.2.3 for the revision

of SOCMI average factors. Attachment 4 to appendix C summarizes

the screening data used to develop the emission factors.

Little documentation is available for the marketing terminal

data because the data were collected and delivered directly to

EPA with no formal report being written. The marketing terminal

emission factors (shown in Tables 2-3 and 2-7) represent

emissions from uncontrolled facilities.

The following five facility types were represented in the

oil and gas production operations screening dataset:

• light crude facilities,

• heavy crude facilities,

• gas plants,

• gas production facilities, and

• offshore facilities.

The 24 oil and gas production operations facilities generally

represent uncontrolled facilities, however, a couple of gas

plants have agency-mandated inspection and maintenance programs.

Anecdotal data were available regarding the control level at

other facilities. A statistical analysis revealed that there

were no significant differences between emission factors for

those groups of sites with some form of inspection and

C-14
maintenance program versus those sites with no such programs13.

Thus, the oil and gas production operations emission factors

(shown in Tables 2-4 and 2-8) represent emissions from

uncontrolled facilities.

C-15
REFERENCES

1. 1993 Study of Refinery Fugitive Emissions from Equipment

Leaks, Volumes I, II, and III, Radian DCN No. 93-209-081-02,

Radian Corporation, Prepared for Western States Petroleum

Association, Glendale, CA, and American Petroleum Institute,

Washington, D.C., 1994.

2. Development of Fugitive Emission Factors and Emission Profiles

for Petroleum Marketing Terminals, Volumes I and II, API 4588,

Radian Corporation, Prepared for American Petroleum Institute,

1993.

3. Fugitive Hydrocarbon Emissions from Oil and Gas Production

Operations, API 4589, Star Environmental, Prepared for American

Petroleum Institute, 1993.

4. Emission Factors for Oil and Gas Production Operations,

API 4615, Star Enivironmental, Prepared for American Petroleum

Institute, 1995.

5. Assessment of Atmospheric Emissions from Petroleum Refining,

EPA-600/2-80-075., U.S. Environmental Protection Agency, Research

Triangle Park, NC, 1980.

6. Petroleum Industry Equipment Leaks: Revised Correlations,

Default Zero Emission Rates, and Pegged Emission Rates for

Estimating VOC Emissions, Developed from 1993 Data from

Refineries, Marketing Terminals, and Oil and Gas Production

Operations, technical memorandum from David Epperson, Radian

Corporation/Reasearch Triangle Park, to David Markwordt, US

EPA/OAQPS, January 27, 1995.

7. Technology Transfer Network (Electronic Bulletin Boards),

Office of Air Quality Planning and Standards, U.S. Environmental

Protection Agency, Research Triangle Park, NC, help desk phone

number: (919) 541-5384, 1-5 pm EST.

8. Assessment of Atmospheric Emissions from Petroleum Refining:

Volume 4, Appendix C, EPA-600/2-80-075d, U.S. Environmental

Protection Agency, Research Triangle Park, NC, 1980.

9. Valve Screening Study at Six San Francisco Bay Area Petroleum

Refineries, Radian DCN No. 79-219-370-05. Radian Corporation,

Prepared for the United States Environmental Protection Agency,

Research Triangle Park, NC, 1979.

10. Letter from Robert Strieter, API, to David Markwordt,

U.S. EPA, regarding the submittal of gasoline distribution

facility fugitive equipment screening data. April 26, 1994.

11. Fugitive Hydrocarbon Emissions from Oil and Gas Production

Operations, API 4589, Star Environmental, Prepared for American

Petroleum Institute, 1993.

C-16
12. Emission Factors for Oil and Gas Production Operations,

API 4615, Star Enivironmental, Prepared for American Petroleum

Institute, 1995.

13. Fax to Eric Peterson, Santa Barbara APCD, Santa Barbara, CA

from G.E. Harris, Radian/Austin, August 31, 1995.

C-17
Figure C-1. Plot of data and regression lines with 95 percent

confidence intervals for the all connector data

from the 1980 (solid lines for regression

equations and confidence bounds; O for individual

data points) and 1993 (dashed lines for regression

equations and confidence bounds; N for individual

data points) refinery reports (screening values

are in ppmv and leak rates in kg/hr).

C-18
Figure C-2. Plot of data and regression lines with 95 percent

confidence intervals for the gas valve data from

the 1980 (solid lines for regression equations and

confidence bounds; O for individual data points)

and 1993 (dashed lines for regression equations

and confidence bounds; N for individual data

points) refinery reports (screening values are

in ppmv and leak rates in kg/hr).

C-19
Figure C-3. Comparison of ratios of predicted to measured mass

formthe 1980 refinery, the 1993 refinery, and the

combined 1980/1993 refinery data (a

predicted-to-measured mass ratio of 1.0 indicates

a perfect prediction). Bars that reach 4.0 on the

chart actually extend beyond 4.0.

C-20
Figure C-4. Plot of data and regression lines with 95 percent

confidence intervals for the light liquid flange

data from the 1993 refinery (solid lines for

regression equations and confidence bounds; R for

individual data points), the 1993 marketing

terminal (short dashed lines for regression

equations and confidence bounds; M for individual

data points), and the 1993 oil and gas production

operations (alternating short and long dashed

lines for regression equations and confidence

bounds; M for individual data points) reports

(screening values are in ppmv and leak rates in

kg/hr).

C-21
Figure C-5. Plot of data and regression lines with 95 percent

confidence intervals for the light liquid valve

data from the 1993 refinery (solid lines for

regression equations and confidence bounds; R for

individual data points), the 1993 marketing

terminal (short dashed lines for regression

equations and confidence bounds; M for individual

data points), and the 1993 oil and gas production

operations (alternating short and long dashed

lines for regression equations and confidence

bounds; M for individual data points) reports

(screening values are in ppmv and leak rates in

kg/hr).

C-22
Figure C-6. Comparison of the ratios of predicted to observed

mass from the 1993 refinery, marketing terminal,

oil and gas production operations, and the

combined refinery/marketing terminal/oil and gas

production operations data (a

predicted-to-measured mass ratio of 1.0 indicates

a perfect prediction). Bars that reach 4.0 on the

chart actually extend beyond 4.0.

C-23
APPENDIX C: ATTACHMENT 1

This attachment lists the bagging data used to develop the

correlation equations for each of the equipment types in

table C-1-1. Also included is a summary table (table C-1-2) of

the regression statistics for the 1993 refinery, marketing

terminal and oil and gas production operations data individually.

Note that the regression statistics presented in table C-1-2 are

based on the development of the regression lines using natural

logarithms of the leak rates and screening values. Table C-1-3

lists the bagging data for the 1980 refinery data while

table C-1-4 presents regression statistics for the 1980 and

1993 refinery data sets.

C-24
TABLE C-1-1. BAGGING DATA USED TO DEVELOP CORRELATION EQUATIONS

---------------------- Equipment Type=CONNECTOR SERVICE=G ----------------------

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

ONOFF 0.00000045360 8.00 -14.606 2.079

REF 0.00000050826 13.00 -14.492 2.565

ONOFF 0.00000181439 1.75 -13.220 0.560

ONOFF 0.00000272158 106.00 -12.814 4.663

ONOFF 0.00000272158 145.00 -12.814 4.977

ONOFF 0.00000453597 70.00 -12.303 4.248

ONOFF 0.00000498957 98.00 -12.208 4.585

ONOFF 0.00000498957 1,045.00 -12.208 6.952

ONOFF 0.00000680396 1,450.00 -11.898 7.279

ONOFF 0.00000725755 440.00 -11.833 6.087

ONOFF 0.00001043273 195.00 -11.471 5.273

ONOFF 0.00001360791 6,240.00 -11.205 8.739

ONOFF 0.00001632949 4,982.00 -11.023 8.514

MT 0.00001732831 30.00 -10.963 3.401

ONOFF 0.00001995827 93.00 -10.822 4.533

ONOFF 0.00002313345 43.00 -10.674 3.761

ONOFF 0.00002903021 890.00 -10.447 6.791

ONOFF 0.00002993740 549.00 -10.416 6.308

ONOFF 0.00003084460 130.50 -10.387 4.871

REF 0.00004677946 267.00 -9.970 5.587

REF 0.00004909734 446.00 -9.922 6.100

REF 0.00006622970 1,196.50 -9.622 7.087

ONOFF 0.00010659530 2,742.00 -9.146 7.916

ONOFF 0.00013245033 1,999.00 -8.929 7.600

ONOFF 0.00014061508 1,985.00 -8.869 7.593

REF 0.00019757326 271.00 -8.529 5.602

MT 0.00027662615 30.00 -8.193 3.401

ONOFF 0.00033566180 790.00 -7.999 6.672

REF 0.00039860292 7,745.00 -7.828 8.955

ONOFF 0.00046040098 3,996.00 -7.683 8.293

ONOFF 0.00049850313 5,498.00 -7.604 8.612

REF 0.00094198494 10,995.00 -6.968 9.305

ONOFF 0.00105688107 8,995.00 -6.852 9.104

REF 0.00220312075 43,995.00 -6.118 10.692

N = 34

C-25
TABLE C-1-1. BAGGING DATA USED TO DEVELOP CORRELATION EQUATIONS

(CONTINUED)

Table C-1-1. Bagging Data Used to Develop Correlation Equations

--------------------- Equipment Type=CONNECTOR SERVICE=HL ----------------------

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

REF 0.00000057407 58.50 -14.371 4.069

ONOFF 0.00001360791 19.50 -11.205 2.970

REF 0.00098339835 8,994.00 -6.924 9.104

N=3

--------------------- Equipment Type=CONNECTOR SERVICE=LL ----------------------

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

REF 0.00000003124 36.50 -17.282 3.597

REF 0.00000032133 38.00 -14.951 3.638

REF 0.00000039502 6.50 -14.744 1.872

ONOFF 0.00000045360 13.50 -14.606 2.603

REF 0.00000069890 18.00 -14.174 2.890

REF 0.00000138429 1,335.00 -13.490 7.197

REF 0.00000140733 26.50 -13.474 3.277

ONOFF 0.00000226799 1,547.00 -12.997 7.344

REF 0.00000252558 1,393.00 -12.889 7.239

ONOFF 0.00000272158 20.00 -12.814 2.996

ONOFF 0.00000272158 41.00 -12.814 3.714

ONOFF 0.00000272158 155.00 -12.814 5.043

ONOFF 0.00000272158 498.00 -12.814 6.211

ONOFF 0.00000362878 75.00 -12.527 4.317

REF 0.00000366230 91.00 -12.517 4.511

ONOFF 0.00000408237 56.00 -12.409 4.025

ONOFF 0.00000408237 96.00 -12.409 4.564

MT 0.00000418117 35.00 -12.385 3.555

ONOFF 0.00000544316 157.50 -12.121 5.059

ONOFF 0.00000589676 200.00 -12.041 5.298

ONOFF 0.00000635036 290.00 -11.967 5.670

ONOFF 0.00000680396 39.00 -11.898 3.664

ONOFF 0.00000816475 4,400.00 -11.716 8.389

MT 0.00001033612 317.00 -11.480 5.759

ONOFF 0.00001133993 294.00 -11.387 5.684

ONOFF 0.00001133993 1,240.00 -11.387 7.123

REF 0.00001226163 1,345.50 -11.309 7.205

ONOFF 0.00001270072 123.00 -11.274 4.812

MT 0.00001529121 23.00 -11.088 3.135

ONOFF 0.00001542230 322.00 -11.080 5.775

C-26
TABLE C-1-1. BAGGING DATA USED TO DEVELOP CORRELATION EQUATIONS

(CONTINUED)

Table C-1-1. Bagging Data Used to Develop Correlation Equations

--------------------- Equipment Type=CONNECTOR SERVICE=LL ----------------------

(continued)

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

ONOFF 0.00001542230 395.00 -11.080 5.979

MT 0.00001610768 23.00 -11.036 3.135

REF 0.00001628413 649.00 -11.025 6.475

ONOFF 0.00001814388 56.00 -10.917 4.025

REF 0.00001880613 19,304.00 -10.881 9.868

ONOFF 0.00002222625 945.00 -10.714 6.851

ONOFF 0.00002267985 825.00 -10.694 6.715

ONOFF 0.00002313345 5,900.00 -10.674 8.683

ONOFF 0.00002585503 172.00 -10.563 5.147

MT 0.00002609816 45.00 -10.554 3.807

MT 0.00002844053 321.00 -10.468 5.771

ONOFF 0.00002993740 121.00 -10.416 4.796

ONOFF 0.00003356618 450.00 -10.302 6.109

MT 0.00003923025 42.50 -10.146 3.750

MT 0.00004271251 670.00 -10.061 6.507

MT 0.00004451148 446.50 -10.020 6.101

MT 0.00004481675 542.00 -10.013 6.295

ONOFF 0.00005080287 6,930.00 -9.888 8.844

ONOFF 0.00005216366 1,996.00 -9.861 7.599

MT 0.00005430464 112.00 -9.821 4.718

MT 0.00005460855 96.00 -9.815 4.564

ONOFF 0.00006304999 3,248.00 -9.672 8.086

REF 0.00006329946 21,996.00 -9.668 9.999

MT 0.00006931416 141.50 -9.577 4.952

MT 0.00008792071 511.00 -9.339 6.236

ONOFF 0.00009570897 8,450.00 -9.254 9.042

ONOFF 0.00010886329 1,245.00 -9.125 7.127

ONOFF 0.00011612084 3,495.00 -9.061 8.159

ONOFF 0.00012247120 1,900.00 -9.008 7.550

ONOFF 0.00013381112 6,998.00 -8.919 8.853

MT 0.00013952191 420.00 -8.877 6.040

ONOFF 0.00018461399 2,992.00 -8.597 8.004

MT 0.00021457407 621.50 -8.447 6.432

ONOFF 0.00021863377 5,990.00 -8.428 8.698

MT 0.00025722126 41.00 -8.266 3.714

ONOFF 0.00026263268 1,249.00 -8.245 7.130

REF 0.00026441985 3,595.50 -8.238 8.187

MT 0.00030734827 270.00 -8.088 5.598

MT 0.00031839790 171.50 -8.052 5.145

ONOFF 0.00032341468 1,993.00 -8.037 7.597

ONOFF 0.00033475460 2,240.00 -8.002 7.714

ONOFF 0.00041640207 290.00 -7.784 5.670

MT 0.00071681938 6,996.00 -7.241 8.853

MT 0.00075932142 940.00 -7.183 6.846

C-27
TABLE C-1-1. BAGGING DATA USED TO DEVELOP CORRELATION EQUATIONS

(CONTINUED)

Table C-1-1. Bagging Data Used to Develop Correlation Equations

--------------------- Equipment Type=CONNECTOR SERVICE=LL ----------------------

(continued)

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

REF 0.00082713417 89,996.50 -7.098 11.408

REF 0.00087190420 62,482.50 -7.045 11.043

REF 0.00090365599 6,492.50 -7.009 8.778

ONOFF 0.00152363240 2,490.00 -6.487 7.820

REF 0.00337970607 52,843.00 -5.690 10.875

REF 0.02082463939 27,493.00 -3.872 10.222

ONOFF 0.15713462760 44,990.00 -1.851 10.714

N = 81

----------------------- Equipment Type=FLANGE SERVICE=G ------------------------

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

REF 0.00000133929 344.50 -13.523 5.842

ONOFF 0.00000272158 46.00 -12.814 3.829

REF 0.00000347791 97.00 -12.569 4.575

MT 0.00000944344 37.50 -11.570 3.624

ONOFF 0.00000952554 122.00 -11.562 4.804

ONOFF 0.00001133993 398.00 -11.387 5.986

ONOFF 0.00003220539 597.00 -10.343 6.392

REF 0.00003784088 81.00 -10.182 4.394

ONOFF 0.00003810215 39.00 -10.175 3.664

ONOFF 0.00005533884 197.00 -9.802 5.283

ONOFF 0.00007076114 1,996.00 -9.556 7.599

ONOFF 0.00054068765 424.00 -7.523 6.050

REF 0.00268479543 4,996.00 -5.920 8.516

ONOFF 0.00444751882 999.00 -5.415 6.907

N = 14

C-28
TABLE C-1-1. BAGGING DATA USED TO DEVELOP CORRELATION EQUATIONS

(CONTINUED)

Table C-1-1. Bagging Data Used to Develop Correlation Equations

----------------------- Equipment Type=FLANGE SERVICE=HL -----------------------

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

REF 0.00000585594 22.50 -12.048 3.114

ONOFF 0.00000907194 345.00 -11.610 5.844

N=2

C-29
TABLE C-1-1. BAGGING DATA USED TO DEVELOP CORRELATION EQUATIONS

(CONTINUED)

Table C-1-1. Bagging Data Used to Develop Correlation Equations

----------------------- Equipment Type=FLANGE SERVICE=LL -----------------------

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

REF 0.00000084061 5.00 -13.989 1.609

REF 0.00000206056 19.50 -13.093 2.970

ONOFF 0.00000317518 84.00 -12.660 4.431

ONOFF 0.00000544316 133.50 -12.121 4.894

MT 0.00000558151 46.00 -12.096 3.829

ONOFF 0.00000680396 4,480.00 -11.898 8.407

REF 0.00001045859 595.50 -11.468 6.389

ONOFF 0.00001315431 174.00 -11.239 5.159

MT 0.00001445342 34.50 -11.145 3.541

ONOFF 0.00001451510 65.00 -11.140 4.174

MT 0.00001889096 50.00 -10.877 3.912

ONOFF 0.00001905108 10.50 -10.868 2.351

ONOFF 0.00002585503 186.00 -10.563 5.226

ONOFF 0.00002903021 530.00 -10.447 6.273

MT 0.00003226209 1,096.50 -10.342 7.000

REF 0.00003390230 69.50 -10.292 4.241

ONOFF 0.00003674136 3,997.00 -10.212 8.293

ONOFF 0.00003764855 192.00 -10.187 5.257

ONOFF 0.00003991654 247.00 -10.129 5.509

MT 0.00005107956 87.00 -9.882 4.466

MT 0.00006298648 1,096.50 -9.673 7.000

REF 0.00007970607 1,996.00 -9.437 7.599

REF 0.00008327588 222.50 -9.393 5.405

REF 0.00012617255 593.00 -8.978 6.385

MT 0.00013896398 392.00 -8.881 5.971

REF 0.00016897850 1,548.00 -8.686 7.345

REF 0.00024779098 3,244.50 -8.303 8.085

ONOFF 0.00025129275 1,145.00 -8.289 7.043

MT 0.00025963440 94.00 -8.256 4.543

REF 0.00030001361 671.00 -8.112 6.509

MT 0.00037563277 27.50 -7.887 3.314

MT 0.00046017418 372.50 -7.684 5.920

MT 0.00090079833 37.50 -7.012 3.624

REF 0.00095309807 20,246.00 -6.956 9.916

MT 0.00096566271 997.00 -6.943 6.905

REF 0.00125641840 34,995.50 -6.679 10.463

REF 0.00169028395 3,997.50 -6.383 8.293

REF 0.00344683843 11,547.00 -5.670 9.354

ONOFF 0.00355030391 1,998.00 -5.641 7.600

REF 0.00382985576 1,495.00 -5.565 7.310

N = 40

C-30
TABLE C-1-1. BAGGING DATA USED TO DEVELOP CORRELATION EQUATIONS

(CONTINUED)

Table C-1-1. Bagging Data Used to Develop Correlation Equations

--------------------- Equipment Type=INSTRUMENT SERVICE=G ----------------------

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

ONOFF 0.00007302912 1,992.00 -9.525 7.597

ONOFF 0.00028259095 29,998.00 -8.172 10.309

N=2

--------------------- Equipment Type=INSTRUMENT SERVICE=LL ---------------------

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

ONOFF 0.00000272158 2,743.00 -12.814 7.917

N=1

----------------------- Equipment Type=LOADARM SERVICE=G -----------------------

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

MT 0.00000641205 18.00 -11.957 2.890

MT 0.00002664338 45.00 -10.533 3.807

MT 0.00007439445 70.00 -9.506 4.248

MT 0.00036316339 19.50 -7.921 2.970

MT 0.00134378118 2,498.50 -6.612 7.823

MT 0.00294180350 387.00 -5.829 5.958

MT 0.00397654903 1,096.00 -5.527 6.999

N=7

C-31
TABLE C-1-1. BAGGING DATA USED TO DEVELOP CORRELATION EQUATIONS

(CONTINUED)

Table C-1-1. Bagging Data Used to Develop Correlation Equations

---------------------- Equipment Type=LOADARM SERVICE=LL -----------------------

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

MT 0.00000263449 3.00 -12.847 1.099

MT 0.00000483852 75.00 -12.239 4.317

MT 0.00000647374 76.00 -11.948 4.331

MT 0.00001007893 6.00 -11.505 1.792

MT 0.00001144289 4.50 -11.378 1.504

MT 0.00001305906 5.50 -11.246 1.705

MT 0.00001802640 33.00 -10.924 3.497

MT 0.00001825229 6.00 -10.911 1.792

MT 0.00002585775 79.00 -10.563 4.369

MT 0.00002943210 26.50 -10.433 3.277

MT 0.00004225755 46.50 -10.072 3.839

MT 0.00005778372 15.00 -9.759 2.708

MT 0.00007896671 70.00 -9.446 4.248

MT 0.00010795156 96.00 -9.134 4.564

MT 0.00012671233 10.50 -8.974 2.351

MT 0.00021594394 145.50 -8.440 4.980

N = 16

C-32
TABLE C-1-1. BAGGING DATA USED TO DEVELOP CORRELATION EQUATIONS

(CONTINUED)

Table C-1-1. Bagging Data Used to Develop Correlation Equations

------------------------- Equipment Type=OEL SERVICE=G -------------------------

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

REF 0.00000077642 20.30 -14.069 3.011

ONOFF 0.00000090719 9.00 -13.913 2.197

ONOFF 0.00000136079 8.00 -13.507 2.079

REF 0.00000177710 60.50 -13.241 4.103

ONOFF 0.00000181439 20.50 -13.220 3.020

ONOFF 0.00000181439 26.50 -13.220 3.277

ONOFF 0.00000181439 30.50 -13.220 3.418

ONOFF 0.00000226799 84.00 -12.997 4.431

ONOFF 0.00000272158 48.00 -12.814 3.871

ONOFF 0.00000272158 195.00 -12.814 5.273

ONOFF 0.00000272158 63.00 -12.814 4.143

ONOFF 0.00000272158 113.50 -12.814 4.732

ONOFF 0.00000362878 440.00 -12.527 6.087

ONOFF 0.00000362878 499.00 -12.527 6.213

REF 0.00000391912 16.50 -12.450 2.803

ONOFF 0.00000408237 546.00 -12.409 6.303

ONOFF 0.00000453597 377.00 -12.303 5.932

ONOFF 0.00000498957 59.00 -12.208 4.078

ONOFF 0.00000544316 24.00 -12.121 3.178

ONOFF 0.00000544316 930.00 -12.121 6.835

ONOFF 0.00000589676 755.00 -12.041 6.627

ONOFF 0.00000771115 65.00 -11.773 4.174

ONOFF 0.00000861834 740.00 -11.662 6.607

ONOFF 0.00000907194 383.00 -11.610 5.948

ONOFF 0.00001043273 600.00 -11.471 6.397

ONOFF 0.00001088633 4,430.00 -11.428 8.396

ONOFF 0.00001133993 250.00 -11.387 5.521

REF 0.00001313209 893.00 -11.240 6.795

ONOFF 0.00001587590 349.00 -11.051 5.855

ONOFF 0.00001859748 2,725.00 -10.892 7.910

ONOFF 0.00002177266 1,745.00 -10.735 7.465

ONOFF 0.00002812302 1,747.00 -10.479 7.466

ONOFF 0.00002857661 1,143.00 -10.463 7.041

ONOFF 0.00003039100 1,400.00 -10.401 7.244

REF 0.00003324186 1,295.00 -10.312 7.166

ONOFF 0.00003447337 1,845.00 -10.275 7.520

REF 0.00004146875 15,068.00 -10.091 9.620

ONOFF 0.00004853488 17,499.00 -9.933 9.770

ONOFF 0.00007166833 820.00 -9.543 6.709

ONOFF 0.00008845142 483.50 -9.333 6.181

ONOFF 0.00010024494 170.00 -9.208 5.136

ONOFF 0.00012065681 1,043.00 -9.023 6.950

ONOFF 0.00013743990 3,400.00 -8.892 8.132

ONOFF 0.00016057335 999.00 -8.737 6.907

ONOFF 0.00016737730 80.00 -8.695 4.382

C-33
TABLE C-1-1. BAGGING DATA USED TO DEVELOP CORRELATION EQUATIONS

(CONTINUED)

Table C-1-1. Bagging Data Used to Develop Correlation Equations

------------------------- Equipment Type=OEL SERVICE=G -------------------------

(continued)

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

ONOFF 0.00020729384 3,746.00 -8.481 8.228

ONOFF 0.00025991109 849.00 -8.255 6.744

ONOFF 0.00029257008 13,497.00 -8.137 9.510

ONOFF 0.00043046358 1,980.00 -7.751 7.591

ONOFF 0.00057652182 27,497.00 -7.458 10.222

ONOFF 0.00084278327 5,998.00 -7.079 8.699

REF 0.00087367323 44,998.00 -7.043 10.714

ONOFF 0.00107184977 5,998.00 -6.838 8.699

ONOFF 0.00229792253 14,999.00 -6.076 9.616

ONOFF 0.04543499955 1,800.00 -3.091 7.496

N = 55

------------------------ Equipment Type=OEL SERVICE=HL -------------------------

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

REF 0.00000137984 195.00 -13.494 5.273

ONOFF 0.00000453597 107.50 -12.303 4.677

ONOFF 0.00000498957 33.50 -12.208 3.512

ONOFF 0.00000544316 75.00 -12.121 4.317

ONOFF 0.00000544316 170.00 -12.121 5.136

ONOFF 0.00000635036 85.50 -11.967 4.449

ONOFF 0.00001224712 75.00 -11.310 4.317

ONOFF 0.00002948381 95.00 -10.432 4.554

ONOFF 0.00005533884 142.00 -9.802 4.956

ONOFF 0.00005715323 58.00 -9.770 4.060

ONOFF 0.00006304999 329.50 -9.672 5.798

ONOFF 0.00008074027 2,994.00 -9.424 8.004

REF 0.00011177991 1,097.50 -9.099 7.001

REF 0.00018571169 15,496.50 -8.591 9.648

ONOFF 0.00045904019 1,194.00 -7.686 7.085

ONOFF 0.00109226163 4,990.00 -6.820 8.515

N = 16

C-34
TABLE C-1-1. BAGGING DATA USED TO DEVELOP CORRELATION EQUATIONS

(CONTINUED)

Table C-1-1. Bagging Data Used to Develop Correlation Equations

------------------------ Equipment Type=OEL SERVICE=LL -------------------------

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

ONOFF 0.00000045360 698.00 -14.606 6.548

REF 0.00000079071 100.00 -14.050 4.605

ONOFF 0.00000090719 293.00 -13.913 5.680

MT 0.00000109340 1.00 -13.726 0.000

ONOFF 0.00000136079 122.00 -13.507 4.804

MT 0.00000179606 2.00 -13.230 0.693

ONOFF 0.00000181439 3.75 -13.220 1.322

REF 0.00000269491 14.50 -12.824 2.674

ONOFF 0.00000272158 96.00 -12.814 4.564

ONOFF 0.00000272158 75.00 -12.814 4.317

ONOFF 0.00000272158 110.00 -12.814 4.700

REF 0.00000272462 1,448.00 -12.813 7.278

MT 0.00000289948 8.00 -12.751 2.079

MT 0.00000312574 1.75 -12.676 0.560

ONOFF 0.00000317518 63.00 -12.660 4.143

ONOFF 0.00000317518 547.00 -12.660 6.304

REF 0.00000396675 488.00 -12.438 6.190

ONOFF 0.00000453597 1,004.00 -12.303 6.912

ONOFF 0.00000725755 180.00 -11.833 5.193

ONOFF 0.00000725755 1,148.00 -11.833 7.046

ONOFF 0.00000771115 148.00 -11.773 4.997

ONOFF 0.00000771115 1,000.50 -11.773 6.908

REF 0.00000810124 247.00 -11.723 5.509

ONOFF 0.00000861834 535.00 -11.662 6.282

MT 0.00001089767 175.50 -11.427 5.168

ONOFF 0.00001224712 3.00 -11.310 1.099

MT 0.00001287898 545.50 -11.260 6.302

ONOFF 0.00001360791 996.00 -11.205 6.904

REF 0.00001366144 522.50 -11.201 6.259

ONOFF 0.00001496870 2.50 -11.110 0.916

ONOFF 0.00002131906 44.00 -10.756 3.784

ONOFF 0.00002585503 1,498.00 -10.563 7.312

ONOFF 0.00002721582 99.00 -10.512 4.595

REF 0.00003169282 1,493.00 -10.359 7.309

REF 0.00003332713 66.50 -10.309 4.197

MT 0.00003502223 296.00 -10.260 5.690

ONOFF 0.00004127733 2,144.00 -10.095 7.670

ONOFF 0.00004399891 1,492.00 -10.031 7.308

MT 0.00004551393 51.00 -9.997 3.932

ONOFF 0.00007529711 849.00 -9.494 6.744

REF 0.00007992833 3,243.00 -9.434 8.084

REF 0.00009666606 14,846.00 -9.244 9.605

ONOFF 0.00010659530 1,748.00 -9.146 7.466

ONOFF 0.00010704890 6,985.00 -9.142 8.852

ONOFF 0.00011067767 796.00 -9.109 6.680

C-35
TABLE C-1-1. BAGGING DATA USED TO DEVELOP CORRELATION EQUATIONS

(CONTINUED)

Table C-1-1. Bagging Data Used to Develop Correlation Equations

------------------------ Equipment Type=OEL SERVICE=LL -------------------------

(continued)

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

ONOFF 0.00012428558 2,200.00 -8.993 7.696

ONOFF 0.00013063594 34,996.00 -8.943 10.463

REF 0.00013571623 535.00 -8.905 6.282

ONOFF 0.00020956183 2,097.00 -8.470 7.648

ONOFF 0.00023541686 2,248.00 -8.354 7.718

MT 0.00028113490 142.00 -8.177 4.956

ONOFF 0.00029483807 1,744.00 -8.129 7.464

REF 0.00035645469 1,996.00 -7.939 7.599

ONOFF 0.00035970244 1,190.00 -7.930 7.082

ONOFF 0.00038510387 4,489.00 -7.862 8.409

MT 0.00053411050 495.00 -7.535 6.205

REF 0.00056373038 12,493.50 -7.481 9.433

MT 0.00056382110 93.00 -7.481 4.533

MT 0.00076480994 1,186.00 -7.176 7.078

MT 0.00082414043 210.00 -7.101 5.347

MT 0.00086428377 1,039.00 -7.054 6.946

REF 0.00092007620 12,990.00 -6.991 9.472

ONOFF 0.00120112492 37,492.00 -6.724 10.532

MT 0.00175405969 990.00 -6.346 6.898

ONOFF 0.00219268802 19,992.00 -6.123 9.903

ONOFF 0.00361471469 42,493.00 -5.623 10.657

ONOFF 0.00594257462 69,994.00 -5.126 11.156

ONOFF 0.00753968974 347.00 -4.888 5.849

REF 0.00883470924 26,795.00 -4.729 10.196

MT 0.05022226254 7,992.00 -2.991 8.986

N = 70

------------------------ Equipment Type=OTHER SERVICE=G ------------------------

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

MT 0.00001317427 970.00 -11.237 6.877

N=1

C-36
TABLE C-1-1. BAGGING DATA USED TO DEVELOP CORRELATION EQUATIONS

(CONTINUED)

Table C-1-1. Bagging Data Used to Develop Correlation Equations

----------------------- Equipment Type=OTHER SERVICE=LL ------------------------

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

MT 0.00000408142 73.00 -12.409 4.290

MT 0.00001337113 3,995.00 -11.222 8.293

MT 0.00003222716 2,991.00 -10.343 8.003

N=3

------------------------- Equipment Type=PRV SERVICE=G -------------------------

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

REF 0.00000184074 2,595.00 -13.205 7.861

ONOFF 0.00000408237 19.00 -12.409 2.944

ONOFF 0.00001451510 81.00 -11.140 4.394

ONOFF 0.00007393631 149.00 -9.512 5.004

ONOFF 0.00010387372 578.50 -9.172 6.360

ONOFF 0.00014651184 1,345.00 -8.828 7.204

ONOFF 0.00029166289 1,741.00 -8.140 7.462

N=7

------------------------ Equipment Type=PRV SERVICE=LL -------------------------

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

REF 0.00000105779 3.80 -13.759 1.335

ONOFF 0.00001496870 297.00 -11.110 5.694

ONOFF 0.00002812302 997.00 -10.479 6.905

ONOFF 0.00024312801 5,491.00 -8.322 8.611

N=4

C-37
TABLE C-1-1. BAGGING DATA USED TO DEVELOP CORRELATION EQUATIONS

(CONTINUED)

Table C-1-1. Bagging Data Used to Develop Correlation Equations

------------------------ Equipment Type=PUMP SERVICE=HL ------------------------

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

REF 0.00000090434 281.00 -13.916 5.638

REF 0.00000241563 10.00 -12.934 2.303

REF 0.00000450227 6.80 -12.311 1.917

REF 0.00001091808 19.00 -11.425 2.944

REF 0.00002612447 18.00 -10.553 2.890

REF 0.00006783543 9.50 -9.598 2.251

REF 0.00032885331 45.50 -8.020 3.818

REF 0.00082590946 323.00 -7.099 5.778

REF 0.00089771387 1,145.50 -7.016 7.044

REF 0.00290669509 277.00 -5.841 5.624

REF 0.01268710877 9,496.50 -4.367 9.159

N = 11

C-38
TABLE C-1-1. BAGGING DATA USED TO DEVELOP CORRELATION EQUATIONS

(CONTINUED)

Table C-1-1. Bagging Data Used to Develop Correlation Equations

------------------------ Equipment Type=PUMP SERVICE=LL ------------------------

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

MT 0.00000569400 24.50 -12.076 3.199

REF 0.00002452599 107.00 -10.616 4.673

MT 0.00002501950 2.00 -10.596 0.693

MT 0.00002550576 20.00 -10.577 2.996

MT 0.00003079742 95.00 -10.388 4.554

REF 0.00003737186 7,999.00 -10.195 8.987

MT 0.00003825274 45.50 -10.171 3.818

REF 0.00004112537 126.00 -10.099 4.836

REF 0.00004198993 192.00 -10.078 5.257

REF 0.00005151955 66.50 -9.874 4.197

REF 0.00006067767 4.50 -9.710 1.504

MT 0.00006509571 5.00 -9.640 1.609

MT 0.00006677855 7.50 -9.614 2.015

REF 0.00014387644 22.00 -8.847 3.091

REF 0.00018934954 21.50 -8.572 3.068

REF 0.00028473646 7,999.00 -8.164 8.987

REF 0.00034099156 136.00 -7.984 4.913

MT 0.00034670235 8,945.50 -7.967 9.099

REF 0.00048530346 127.00 -7.631 4.844

REF 0.00052476640 15.50 -7.553 2.741

REF 0.00059974599 1,780.00 -7.419 7.484

REF 0.00062650821 66.00 -7.375 4.190

MT 0.00066574435 43.00 -7.315 3.761

REF 0.00082055702 27,996.00 -7.106 10.240

REF 0.00086514560 33,744.50 -7.053 10.427

MT 0.00092406786 6,868.00 -6.987 8.835

REF 0.00095527533 5,970.00 -6.954 8.695

REF 0.00119445704 22,995.00 -6.730 10.043

REF 0.00121223805 1,394.00 -6.715 7.240

REF 0.00122534700 621.00 -6.705 6.431

REF 0.00153538057 183.50 -6.479 5.212

REF 0.00179438447 1,697.00 -6.323 7.437

REF 0.00220076204 947.00 -6.119 6.853

REF 0.00301020593 996.00 -5.806 6.904

REF 0.00489884786 395.00 -5.319 5.979

REF 0.00679034746 5,745.50 -4.992 8.656

REF 0.00757234873 4,997.00 -4.883 8.517

REF 0.00958087635 41,995.00 -4.648 10.645

REF 0.00968248208 13,995.00 -4.637 9.546

MT 0.01317699356 4,488.00 -4.329 8.409

REF 0.03439081920 17,694.50 -3.370 9.781

ONOFF 0.07243808401 4,992.00 -2.625 8.516

N = 42

C-39
TABLE C-1-1. BAGGING DATA USED TO DEVELOP CORRELATION EQUATIONS

(CONTINUED)

Table C-1-1. Bagging Data Used to Develop Correlation Equations

-------------------- Equipment Type=STUFFING BOX SERVICE=HL --------------------

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

ONOFF 0.00000317518 26.00 -12.660 3.258

ONOFF 0.00000317518 46.00 -12.660 3.829

ONOFF 0.00000317518 47.50 -12.660 3.861

ONOFF 0.00000544316 75.00 -12.121 4.317

ONOFF 0.00000589676 162.00 -12.041 5.088

ONOFF 0.00001043273 145.00 -11.471 4.977

ONOFF 0.00001451510 145.00 -11.140 4.977

ONOFF 0.00004127733 127.00 -10.095 4.844

ONOFF 0.00007076114 294.00 -9.556 5.684

ONOFF 0.00089630772 795.00 -7.017 6.678

ONOFF 0.00129592670 1,095.00 -6.649 6.999

N = 11

-------------------- Equipment Type=STUFFING BOX SERVICE=LL --------------------

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

ONOFF 0.00014197587 293.00 -8.860 5.680

ONOFF 0.00032114669 842.00 -8.044 6.736

ONOFF 0.00046266896 630.00 -7.678 6.446

ONOFF 0.00052390456 71.00 -7.554 4.263

ONOFF 0.00059421210 647.00 -7.428 6.472

ONOFF 0.00107321056 4,498.00 -6.837 8.411

ONOFF 0.00114442529 1,246.00 -6.773 7.128

ONOFF 0.00120611449 992.00 -6.720 6.900

ONOFF 0.00142293387 748.00 -6.555 6.617

ONOFF 0.00371586682 3,994.00 -5.595 8.293

ONOFF 0.00399664338 4,498.00 -5.522 8.411

ONOFF 0.00602331489 3,496.00 -5.112 8.159

N = 12

C-40
TABLE C-1-1. BAGGING DATA USED TO DEVELOP CORRELATION EQUATIONS

(CONTINUED)

Table C-1-1. Bagging Data Used to Develop Correlation Equations

------------------------ Equipment Type=VALVE SERVICE=G ------------------------

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

ONOFF 0.00000045360 1.25 -14.606 0.223

ONOFF 0.00000045360 9.00 -14.606 2.197

ONOFF 0.00000045360 52.50 -14.606 3.961

ONOFF 0.00000045360 1,997.00 -14.606 7.599

ONOFF 0.00000090719 122.00 -13.913 4.804

REF 0.00000108460 150.00 -13.734 5.011

ONOFF 0.00000136079 142.00 -13.507 4.956

REF 0.00000162324 78.00 -13.331 4.357

MT 0.00000211567 295.50 -13.066 5.689

MT 0.00000226853 1.00 -12.996 0.000

ONOFF 0.00000272158 46.50 -12.814 3.839

ONOFF 0.00000272158 227.50 -12.814 5.427

ONOFF 0.00000317518 31.50 -12.660 3.450

ONOFF 0.00000317518 42.00 -12.660 3.738

REF 0.00000322045 33.00 -12.646 3.497

REF 0.00000323338 23.50 -12.642 3.157

ONOFF 0.00000453597 180.00 -12.303 5.193

REF 0.00000474236 11.00 -12.259 2.398

ONOFF 0.00000498957 1,497.00 -12.208 7.311

ONOFF 0.00000498957 1,780.00 -12.208 7.484

REF 0.00000566633 68.50 -12.081 4.227

REF 0.00000584324 50.00 -12.050 3.912

ONOFF 0.00000635036 749.00 -11.967 6.619

REF 0.00000662796 22.50 -11.924 3.114

ONOFF 0.00000725755 1,620.00 -11.833 7.390

ONOFF 0.00000907194 648.00 -11.610 6.474

ONOFF 0.00000952554 299.00 -11.562 5.700

REF 0.00000959040 105.00 -11.555 4.654

ONOFF 0.00000997913 3.50 -11.515 1.253

ONOFF 0.00000997913 3.50 -11.515 1.253

REF 0.00001004944 240.00 -11.508 5.481

REF 0.00001313209 66.00 -11.240 4.190

REF 0.00001568266 306.00 -11.063 5.724

REF 0.00001582872 26.00 -11.054 3.258

REF 0.00001608773 1,194.50 -11.037 7.085

ONOFF 0.00001905108 1,300.00 -10.868 7.170

REF 0.00001952236 724.00 -10.844 6.585

ONOFF 0.00002177266 96.00 -10.735 4.564

ONOFF 0.00002404064 236.50 -10.636 5.466

REF 0.00002500272 13.00 -10.597 2.565

ONOFF 0.00002721582 115.00 -10.512 4.745

REF 0.00002723941 100.00 -10.511 4.605

REF 0.00002964075 1,495.00 -10.426 7.310

REF 0.00002977456 798.50 -10.422 6.683

ONOFF 0.00002993740 71.00 -10.416 4.263

C-41
TABLE C-1-1. BAGGING DATA USED TO DEVELOP CORRELATION EQUATIONS

(CONTINUED)

Table C-1-1. Bagging Data Used to Develop Correlation Equations

------------------------ Equipment Type=VALVE SERVICE=G ------------------------

(continued)

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

ONOFF 0.00003039100 3,485.00 -10.401 8.156

ONOFF 0.00003129819 1,880.00 -10.372 7.539

REF 0.00003320285 297.00 -10.313 5.694

ONOFF 0.00003538057 870.00 -10.249 6.768

ONOFF 0.00004581330 1,746.00 -9.991 7.465

REF 0.00004823551 396.50 -9.939 5.983

ONOFF 0.00004853488 490.00 -9.933 6.194

REF 0.00005161027 195.50 -9.872 5.276

ONOFF 0.00005171006 1,048.00 -9.870 6.955

REF 0.00005379207 331.50 -9.830 5.804

REF 0.00005465391 22.50 -9.814 3.114

REF 0.00005555656 1,049.00 -9.798 6.956

ONOFF 0.00005760682 918.00 -9.762 6.822

REF 0.00005882700 1,045.00 -9.741 6.952

REF 0.00006236052 515.00 -9.683 6.244

ONOFF 0.00006441078 169.00 -9.650 5.130

REF 0.00006601651 496.50 -9.626 6.208

ONOFF 0.00006713236 795.00 -9.609 6.678

ONOFF 0.00007030754 498.00 -9.563 6.211

ONOFF 0.00007166833 1,497.00 -9.543 7.311

REF 0.00007594121 420.00 -9.486 6.040

ONOFF 0.00008618343 249.00 -9.359 5.517

REF 0.00008973964 922.00 -9.319 6.827

ONOFF 0.00009434818 1,748.00 -9.269 7.466

REF 0.00009616711 197.50 -9.249 5.286

REF 0.00009735099 996.00 -9.237 6.904

REF 0.00010011794 1,397.00 -9.209 7.242

ONOFF 0.00010160573 525.00 -9.194 6.263

ONOFF 0.00010523451 3,993.00 -9.159 8.292

ONOFF 0.00010886329 8,180.00 -9.125 9.009

ONOFF 0.00011158487 1,996.00 -9.101 7.599

ONOFF 0.00011294566 499.00 -9.089 6.213

ONOFF 0.00012564638 749.00 -8.982 6.619

ONOFF 0.00013154314 780.00 -8.936 6.659

ONOFF 0.00013426472 785.00 -8.916 6.666

ONOFF 0.00013426472 8,400.00 -8.916 9.036

ONOFF 0.00014605824 3,999.00 -8.832 8.294

ONOFF 0.00014651184 1,997.00 -8.828 7.599

ONOFF 0.00017327406 1,994.00 -8.661 7.598

ONOFF 0.00018053162 290.00 -8.620 5.670

REF 0.00018855575 2,343.00 -8.576 7.759

REF 0.00019906105 142.00 -8.522 4.956

REF 0.00019947836 830.00 -8.520 6.721

ONOFF 0.00021727297 243.00 -8.434 5.493

C-42
TABLE C-1-1. BAGGING DATA USED TO DEVELOP CORRELATION EQUATIONS

(CONTINUED)

Table C-1-1. Bagging Data Used to Develop Correlation Equations

------------------------ Equipment Type=VALVE SERVICE=G ------------------------

(continued)

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

ONOFF 0.00021818017 5,725.00 -8.430 8.653

REF 0.00022242130 4,246.00 -8.411 8.354

REF 0.00022387281 297.00 -8.404 5.694

REF 0.00023074027 735.00 -8.374 6.600

ONOFF 0.00023904563 798.00 -8.339 6.682

ONOFF 0.00026898304 999.00 -8.221 6.907

ONOFF 0.00026898304 1,165.00 -8.221 7.060

REF 0.00028817473 3,898.40 -8.152 8.268

ONOFF 0.00029257008 14,995.00 -8.137 9.615

ONOFF 0.00031887871 1,998.00 -8.051 7.600

ONOFF 0.00031978590 1,339.00 -8.048 7.200

ONOFF 0.00032114669 1,339.00 -8.044 7.200

ONOFF 0.00033203302 2,999.00 -8.010 8.006

REF 0.00033339381 7,995.50 -8.006 8.987

REF 0.00033416946 996.00 -8.004 6.904

ONOFF 0.00034972331 7,492.00 -7.958 8.922

REF 0.00035323415 22,495.00 -7.948 10.021

REF 0.00038567541 16,496.00 -7.861 9.711

REF 0.00041993559 1,949.00 -7.775 7.575

ONOFF 0.00043137077 2,997.00 -7.749 8.005

ONOFF 0.00043227796 3,990.00 -7.746 8.292

ONOFF 0.00053070852 3,998.00 -7.541 8.294

REF 0.00060437268 65,699.00 -7.411 11.093

ONOFF 0.00066542683 1,045.00 -7.315 6.952

REF 0.00066864737 3,493.00 -7.310 8.159

ONOFF 0.00069445704 740.00 -7.272 6.607

ONOFF 0.00074027034 699.00 -7.208 6.550

ONOFF 0.00082191781 7,495.00 -7.104 8.922

ONOFF 0.00090220448 69,995.00 -7.011 11.156

ONOFF 0.00094484260 14,999.00 -6.964 9.616

ONOFF 0.00102558287 3,241.00 -6.882 8.084

ONOFF 0.00109815840 44,998.00 -6.814 10.714

REF 0.00111190239 79,998.80 -6.802 11.290

ONOFF 0.00111358069 1,444.00 -6.800 7.275

ONOFF 0.00115621882 4,491.00 -6.763 8.410

ONOFF 0.00124965980 6,000.00 -6.685 8.700

REF 0.00132495691 7,998.00 -6.626 8.987

ONOFF 0.00145377846 2,499.00 -6.534 7.824

ONOFF 0.00155719858 5,235.00 -6.465 8.563

ONOFF 0.00207339200 3,465.00 -6.179 8.150

ONOFF 0.00244851674 2,696.00 -6.012 7.900

ONOFF 0.00269255194 44,995.00 -5.917 10.714

ONOFF 0.00380250386 7,499.00 -5.572 8.923

REF 0.01290846412 2,993.00 -4.350 8.004

C-43
TABLE C-1-1. BAGGING DATA USED TO DEVELOP CORRELATION EQUATIONS

(CONTINUED)

Table C-1-1. Bagging Data Used to Develop Correlation Equations

------------------------ Equipment Type=VALVE SERVICE=G ------------------------

(continued)

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

ONOFF 0.01376394811 3,498.00 -4.286 8.160

ONOFF 0.01612628141 49,998.00 -4.127 10.820

ONOFF 0.04505624603 64,998.00 -3.100 11.082

N = 136

----------------------- Equipment Type=VALVE SERVICE=HL ------------------------

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

REF 0.00000007416 22.00 -16.417 3.091

REF 0.00000024878 31.00 -15.207 3.434

REF 0.00000384555 28.00 -12.469 3.332

REF 0.00000417178 23.50 -12.387 3.157

REF 0.00000515059 30.50 -12.176 3.418

REF 0.00000583507 18.50 -12.052 2.918

ONOFF 0.00001043273 120.00 -11.471 4.787

REF 0.00002810986 121.00 -10.479 4.796

REF 0.00003200898 505.00 -10.349 6.225

REF 0.00003625011 122.50 -10.225 4.808

REF 0.00004638030 42.00 -9.979 3.738

REF 0.00007379116 167.00 -9.514 5.118

REF 0.00012682573 92.00 -8.973 4.522

REF 0.00022685294 183.00 -8.391 5.209

REF 0.00025173728 290.00 -8.287 5.670

REF 0.00028499501 464.00 -8.163 6.140

REF 0.00031120838 540.00 -8.075 6.292

REF 0.00040606459 446.00 -7.809 6.100

REF 0.00042830899 956.50 -7.756 6.863

REF 0.00047713871 2,097.50 -7.648 7.649

REF 0.00049600835 2,993.00 -7.609 8.004

REF 0.00223700445 11,494.00 -6.103 9.350

REF 0.01003356618 1,996.00 -4.602 7.599

N = 23

C-44
TABLE C-1-1. BAGGING DATA USED TO DEVELOP CORRELATION EQUATIONS

(CONTINUED)

Table C-1-1. Bagging Data Used to Develop Correlation Equations

----------------------- Equipment Type=VALVE SERVICE=LL ------------------------

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

ONOFF 0.00000045360 510.00 -14.606 6.234

REF 0.00000067060 46.50 -14.215 3.839

ONOFF 0.00000090719 3,210.00 -13.913 8.074

REF 0.00000097029 5.50 -13.846 1.705

REF 0.00000097655 51.00 -13.839 3.932

REF 0.00000124345 5.50 -13.598 1.705

REF 0.00000157471 31.50 -13.361 3.450

ONOFF 0.00000181439 8.75 -13.220 2.169

ONOFF 0.00000181439 26.00 -13.220 3.258

REF 0.00000189545 50.00 -13.176 3.912

REF 0.00000203465 26.00 -13.105 3.258

MT 0.00000205103 4.25 -13.097 1.447

REF 0.00000209952 15.00 -13.074 2.708

REF 0.00000232450 23.50 -12.972 3.157

MT 0.00000237776 10.00 -12.949 2.303

REF 0.00000248467 33.50 -12.905 3.512

REF 0.00000401492 136.00 -12.425 4.913

MT 0.00000447800 11.50 -12.316 2.442

REF 0.00000502041 80.00 -12.202 4.382

ONOFF 0.00000635036 274.00 -11.967 5.613

REF 0.00000640298 128.50 -11.959 4.856

ONOFF 0.00000816475 49.00 -11.716 3.892

REF 0.00000834528 51.00 -11.694 3.932

ONOFF 0.00000861834 89.00 -11.662 4.489

MT 0.00000862560 524.00 -11.661 6.261

REF 0.00000895128 119.50 -11.624 4.783

MT 0.00000984079 18.00 -11.529 2.890

ONOFF 0.00000997913 142.00 -11.515 4.956

REF 0.00001072938 60.00 -11.443 4.094

REF 0.00001154767 17.00 -11.369 2.833

REF 0.00001223850 3.50 -11.311 1.253

MT 0.00001432233 59.50 -11.154 4.086

ONOFF 0.00001496870 15.50 -11.110 2.741

MT 0.00001524449 22.00 -11.091 3.091

MT 0.00001602150 34.00 -11.042 3.526

MT 0.00001613626 28.50 -11.034 3.350

REF 0.00001662116 173.00 -11.005 5.153

ONOFF 0.00001769028 339.00 -10.942 5.826

REF 0.00001839744 47.50 -10.903 3.861

ONOFF 0.00002086546 1,197.00 -10.777 7.088

ONOFF 0.00002131906 148.00 -10.756 4.997

ONOFF 0.00002267985 298.00 -10.694 5.697

MT 0.00002288442 74.00 -10.685 4.304

ONOFF 0.00002358705 59.00 -10.655 4.078

ONOFF 0.00002404064 210.00 -10.636 5.347

C-45
TABLE C-1-1. BAGGING DATA USED TO DEVELOP CORRELATION EQUATIONS

(CONTINUED)

Table C-1-1. Bagging Data Used to Develop Correlation Equations

----------------------- Equipment Type=VALVE SERVICE=LL ------------------------

(continued)

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

MT 0.00002413726 588.00 -10.632 6.377

ONOFF 0.00002449424 1,398.00 -10.617 7.243

MT 0.00002719722 75.00 -10.512 4.317

ONOFF 0.00002721582 8,960.00 -10.512 9.101

REF 0.00002937177 646.00 -10.435 6.471

ONOFF 0.00003175179 2,497.00 -10.358 7.823

REF 0.00003262633 176.00 -10.330 5.170

MT 0.00003474508 45.00 -10.267 3.807

ONOFF 0.00003492697 1,143.00 -10.262 7.041

MT 0.00003817473 119.00 -10.173 4.779

MT 0.00003920348 181.00 -10.147 5.198

REF 0.00004325547 400.50 -10.048 5.993

ONOFF 0.00004399891 441.00 -10.031 6.089

MT 0.00004902930 116.00 -9.923 4.754

MT 0.00005014515 109.00 -9.901 4.691

REF 0.00005050349 447.50 -9.893 6.104

MT 0.00005156491 22.00 -9.873 3.091

ONOFF 0.00005352445 1,998.00 -9.835 7.600

MT 0.00005386918 205.00 -9.829 5.323

MT 0.00005803320 691.00 -9.754 6.538

MT 0.00005873628 124.00 -9.742 4.820

REF 0.00005976594 108.80 -9.725 4.690

REF 0.00005993377 793.00 -9.722 6.676

REF 0.00006152590 100.00 -9.696 4.605

MT 0.00006221537 116.00 -9.685 4.754

REF 0.00006287762 2,496.00 -9.674 7.822

MT 0.00006335843 61.00 -9.667 4.111

MT 0.00006978137 71.50 -9.570 4.270

ONOFF 0.00007575070 3,249.00 -9.488 8.086

ONOFF 0.00007756509 272.00 -9.464 5.606

REF 0.00007775560 2,645.50 -9.462 7.881

REF 0.00008625601 26.50 -9.358 3.277

REF 0.00008785721 192.00 -9.340 5.257

ONOFF 0.00009026581 193.00 -9.313 5.263

ONOFF 0.00009661617 2,246.00 -9.245 7.717

REF 0.00009754604 74.00 -9.235 4.304

ONOFF 0.00010342012 17,499.00 -9.177 9.770

REF 0.00010648644 1,196.00 -9.147 7.087

REF 0.00011324050 595.00 -9.086 6.389

MT 0.00012015785 496.50 -9.027 6.208

REF 0.00012067949 5,000.00 -9.022 8.517

REF 0.00012075660 224.00 -9.022 5.412

REF 0.00013744443 23,996.00 -8.892 10.086

ONOFF 0.00014106867 2,998.00 -8.866 8.006

C-46
TABLE C-1-1. BAGGING DATA USED TO DEVELOP CORRELATION EQUATIONS

(CONTINUED)

Table C-1-1. Bagging Data Used to Develop Correlation Equations

----------------------- Equipment Type=VALVE SERVICE=LL ------------------------

(continued)

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

MT 0.00014320058 132.00 -8.851 4.883

REF 0.00015138801 796.50 -8.796 6.680

REF 0.00015260365 2,096.50 -8.788 7.648

REF 0.00015486256 1,044.00 -8.773 6.951

ONOFF 0.00016102694 3,950.00 -8.734 8.281

ONOFF 0.00016374853 798.00 -8.717 6.682

REF 0.00016769028 894.00 -8.693 6.796

ONOFF 0.00016783090 1,997.00 -8.693 7.599

ONOFF 0.00018461399 1,995.00 -8.597 7.598

ONOFF 0.00018461399 2,244.00 -8.597 7.716

ONOFF 0.00019867550 2,998.00 -8.524 8.006

ONOFF 0.00020185068 1,344.00 -8.508 7.203

ONOFF 0.00021545859 596.00 -8.443 6.390

REF 0.00021628867 1,348.00 -8.439 7.206

REF 0.00022579153 3,493.00 -8.396 8.159

REF 0.00022907557 568.00 -8.381 6.342

MT 0.00023388370 20,897.00 -8.361 9.947

MT 0.00024798603 2,744.00 -8.302 7.917

REF 0.00025930781 12,145.50 -8.257 9.405

REF 0.00026239681 2,736.00 -8.246 7.914

ONOFF 0.00027306541 8,450.00 -8.206 9.042

MT 0.00027484804 4,996.50 -8.199 8.516

REF 0.00028502676 1,345.00 -8.163 7.204

REF 0.00028960809 1,248.00 -8.147 7.129

REF 0.00029077384 372.50 -8.143 5.920

MT 0.00029242947 187.50 -8.137 5.234

REF 0.00029891137 105.00 -8.115 4.654

REF 0.00029939672 794.00 -8.114 6.677

MT 0.00031903747 52.50 -8.050 3.961

REF 0.00032606822 4,997.50 -8.028 8.517

ONOFF 0.00032704345 498.00 -8.025 6.211

ONOFF 0.00033611540 253.50 -7.998 5.535

REF 0.00035377846 34,996.50 -7.947 10.463

REF 0.00035974780 2,240.00 -7.930 7.714

ONOFF 0.00036106323 198.00 -7.926 5.288

MT 0.00036868820 4,545.00 -7.906 8.422

ONOFF 0.00037240316 975.00 -7.896 6.882

MT 0.00041536787 3,243.00 -7.786 8.084

MT 0.00042058423 4,246.50 -7.774 8.354

MT 0.00043848771 21,994.00 -7.732 9.999

REF 0.00044372675 42,745.50 -7.720 10.663

REF 0.00045395990 893.00 -7.698 6.795

REF 0.00046035562 20,246.50 -7.684 9.916

REF 0.00046933684 796.00 -7.664 6.680

C-47
TABLE C-1-1. BAGGING DATA USED TO DEVELOP CORRELATION EQUATIONS

(CONTINUED)

Table C-1-1. Bagging Data Used to Develop Correlation Equations

----------------------- Equipment Type=VALVE SERVICE=LL ------------------------

(continued)

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

REF 0.00047251202 8,490.00 -7.657 9.047

REF 0.00047945205 3,996.00 -7.643 8.293

REF 0.00049981856 159.50 -7.601 5.072

ONOFF 0.00052617255 19,998.00 -7.550 9.903

REF 0.00057253016 674.00 -7.465 6.513

REF 0.00060782001 23,994.50 -7.406 10.086

REF 0.00061521364 1,598.00 -7.394 7.377

MT 0.00062442166 2,147.50 -7.379 7.672

REF 0.00063122562 2,992.00 -7.368 8.004

REF 0.00066533612 133.50 -7.315 4.894

REF 0.00068511295 995.00 -7.286 6.903

ONOFF 0.00070443618 19,994.00 -7.258 9.903

MT 0.00071074118 8,091.00 -7.249 8.999

ONOFF 0.00075932142 54,997.00 -7.183 10.915

REF 0.00095572893 39,996.50 -6.953 10.597

REF 0.00098348907 1,695.00 -6.924 7.435

ONOFF 0.00102558287 54,995.00 -6.882 10.915

MT 0.00103914542 2,745.00 -6.869 7.918

REF 0.00107547854 474.00 -6.835 6.161

REF 0.00113353896 10,997.00 -6.782 9.305

ONOFF 0.00114669328 2,982.00 -6.771 8.000

ONOFF 0.00118570262 2,998.00 -6.737 8.006

MT 0.00134518734 2,257.50 -6.611 7.722

REF 0.00134786356 79,997.00 -6.609 11.290

ONOFF 0.00135444071 1,046.00 -6.604 6.953

REF 0.00135698086 7,497.00 -6.602 8.922

REF 0.00153742175 21,495.00 -6.478 9.976

MT 0.00160918080 5,434.00 -6.432 8.600

ONOFF 0.00169010251 2,740.00 -6.383 7.916

REF 0.00183253198 6,690.00 -6.302 8.808

MT 0.00188274517 8,994.00 -6.275 9.104

MT 0.00197233058 5,494.00 -6.229 8.611

REF 0.00213984396 15,998.50 -6.147 9.680

ONOFF 0.00223351175 54,998.00 -6.104 10.915

MT 0.00239059240 3,844.00 -6.036 8.254

ONOFF 0.00247028939 42,492.00 -6.003 10.657

ONOFF 0.00256236959 2,496.00 -5.967 7.822

REF 0.00258328041 1,004.00 -5.959 6.912

MT 0.00279048353 3,389.00 -5.882 8.128

MT 0.00305193686 3,302.00 -5.792 8.102

REF 0.00312115577 1,243.00 -5.770 7.125

REF 0.00471287308 2,498.00 -5.357 7.823

REF 0.00601378935 25,895.50 -5.114 10.162

REF 0.01730744806 25,490.00 -4.057 10.146

C-48
TABLE C-1-1. BAGGING DATA USED TO DEVELOP CORRELATION EQUATIONS

(CONTINUED)

Table C-1-1. Bagging Data Used to Develop Correlation Equations

----------------------- Equipment Type=VALVE SERVICE=LL ------------------------

(continued)

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

REF 0.02037603193 72,924.00 -3.893 11.197

N = 178

------------------------ Equipment Type=VENT SERVICE=G -------------------------

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

ONOFF 0.00000952554 99.00 -11.562 4.595

ONOFF 0.00005261725 1,998.00 -9.852 7.600

ONOFF 0.00033883698 894.00 -7.990 6.796

N=3

------------------------ Equipment Type=VENT SERVICE=LL ------------------------

Natural Natural

Log of Log of

Measured Emission Screening

Plant Emission Screening Rate Value

Type Rate(kg/hr) Value (ppmv) (kg/hr) (ppmv)

ONOFF 0.00010478091 1,496.00 -9.164 7.311

ONOFF 0.00014877982 396.00 -8.813 5.981

ONOFF 0.00093168829 3,497.00 -6.979 8.160

N=3

C-49
Table C-1-2. REGRESSION STATISTICS FOR THE 1993 REFINERY, MARKETING TER

AND GAS PRODUCTION OPERATIONS DATA

Equipment

Facility

Typea

Sample

Size

Intercept

(b0)

Slope

(b1)

Root Mean

Square

Error

(RMSE)

Coefficient

of Simple

Determination

(R2)

Scale BiasCorrection

Factor(SBCF)

Mean ln

Screening

Value

Type Service 

Connector Light Liquid

REF93 18 -18.01355 1.005 1.960 0.7353 5.2595 7.12669 

MT93 21 -12.57236 0.560 1.144 0.3456 1.8293 5.28173 

OAG93 42 -15.95523 0.860 1.564 0.5223 3.1956 6.40961 

Flange Light Liquid

REF93 15 -14.91663 0.891 1.316 0.7503 2.1504 6.79160 

MT93 12 -10.41103 0.237 1.748 0.0413 3.5250 5.00211 

OAG93 13 -12.88458 0.430 1.715 0.1721 3.4347 5.73992 

Open-Ended

Line

Light

Liquid

REF93 15 -16.36068 0.907 1.693 0.5966 3.4293 6.97954 

MT93 16 -14.01355 0.995 1.614 0.7372 3.1160 4.71076 

OAG93 39 -14.59519 0.668 1.929 0.4218 5.6760 6.50333 

Pump Light Liquid REF93 30 -10.07607 0.419 1.579 0.3281 3.1882 6.71261 

MT93 11 -11.40718 0.527 1.617 0.5128 2.2985 4.45340 

Valve Gas

REF93 50 -13.94624 0.675 1.245 0.5725 2.1124 6.22836 OAG93 84 -15.20999 0.858 1.708 0.5296 4.1228 6.92689 

Valve Light Liquid

REF93 82 -14.17854 0.783 1.453 0.6340 2.7995 6.56265 

MT93 45 -13.29112 0.705 1.071 0.7036 1.7392 5.89259 

OAG93 51 -13.79570 0.633 1.635 0.3949 3.5907 7.02241 

aFacility types are: REF93=1993 refinery data, MT93=1993 marketing termi

OAG93=1993 oil and gas production operations data

C-50
Table C-1-3. 1980 Refinery Data

--------------------- Equipment Type=CONNECTOR SERVICE=ALL ---------------------

Natural Natural Natural

Log of Log of TLV Log of OVA

Measured Original TLV OVA Adjusted Emission Screening Screening

Emission Screening Screening Rate Value Value

Rate(kg/hr) Value (ppmv) Value (ppmv) (kg/hr) (ppmv (ppmv

0.00002862 68.49 135.17 -10.461 4.227 4.907

0.00007993 287.96 611.03 -9.434 5.663 6.415

0.00011026 43.00 82.89 -9.113 3.761 4.418

0.00011643 336.64 719.98 -9.058 5.819 6.579

0.00015369 576.42 1,266.67 -8.781 6.357 7.144

0.00021599 199.00 414.48 -8.440 5.293 6.027

0.00021940 21.47 39.96 -8.425 3.066 3.688

0.00022339 289.36 614.14 -8.407 5.668 6.420

0.00029047 1,447.68 3,332.47 -8.144 7.278 8.111

0.00031247 914.91 2,057.90 -8.071 6.819 7.629

0.00044767 425.98 921.92 -7.711 6.054 6.826

0.00045162 451.40 979.81 -7.703 6.112 6.887

0.00045829 914.48 2,056.87 -7.688 6.818 7.629

0.00058280 214.08 447.53 -7.448 5.366 6.104

0.00061930 398.97 860.61 -7.387 5.989 6.758

0.00062396 912.27 2,051.66 -7.379 6.816 7.626

0.00062744 677.13 1,500.12 -7.374 6.518 7.313

0.00084939 106.60 215.14 -7.071 4.669 5.371

0.00085546 582.26 1,280.16 -7.064 6.367 7.155

0.00087692 1,959.67 4,580.42 -7.039 7.581 8.430

0.00089035 921.20 2,072.75 -7.024 6.826 7.637

0.00117035 4,529.79 11,044.58 -6.750 8.418 9.310

0.00170106 198.70 413.81 -6.377 5.292 6.025

0.00173544 726.19 1,614.50 -6.356 6.588 7.387

0.00177404 3,302.89 7,925.90 -6.334 8.103 8.978

0.00179269 2,290.01 5,394.75 -6.324 7.736 8.593

0.00179403 999.45 2,258.09 -6.323 6.907 7.722

0.00231632 4,214.88 10,239.49 -6.068 8.346 9.234

0.00242557 2,860.43 6,814.53 -6.022 7.959 8.827

0.00342813 3,385.21 8,133.54 -5.676 8.127 9.004

0.00342813 3,385.21 8,133.54 -5.676 8.127 9.004

0.00467383 3,933.75 9,523.33 -5.366 8.277 9.161

0.00468673 3,933.74 9,523.31 -5.363 8.277 9.161

0.00468673 3,933.74 9,523.31 -5.363 8.277 9.161

0.00670911 496.56 1,083.02 -5.004 6.208 6.988

0.00956087 1,981.92 4,635.07 -4.650 7.592 8.441

0.00988148 4,890.96 11,971.40 -4.617 8.495 9.390

0.01433650 4,984.13 12,211.05 -4.245 8.514 9.410

N = 38

C-51
Table C-1-3. 1980 Refinery Data (Con’t.)

----------------------- Equipment Type=DRAIN SERVICE=ALL -----------------------

Natural Natural Natural

Log of Log of TLV Log of OVA

Measured Original TLV OVA Adjusted Emission Screening Screening

Emission Screening Screening Rate Value Value

Rate(kg/hr) Value (ppmv) Value (ppmv) (kg/hr) (ppmv (ppmv

0.00000165 124.56 253.38 -13.318 4.825 5.535

0.00001587 124.20 252.60 -11.051 4.822 5.532

0.00002657 125.41 255.18 -10.536 4.832 5.542

0.00006707 306.36 652.11 -9.610 5.725 6.480

0.00016828 1,084.56 2,460.50 -8.690 6.989 7.808

0.00025242 110.79 224.04 -8.284 4.708 5.412

0.00066593 4.88 8.44 -7.314 1.586 2.133

0.00067665 247.44 521.05 -7.298 5.511 6.256

0.00109637 255.86 539.70 -6.816 5.545 6.291

0.00111300 1,093.11 2,480.86 -6.801 6.997 7.816

0.00163974 9,675.85 24,512.03 -6.413 9.177 10.107

0.00164782 84.27 168.08 -6.408 4.434 5.124

0.00168344 249.76 526.17 -6.387 5.520 6.266

0.00168969 249.75 526.16 -6.383 5.520 6.266

0.00169157 1,095.50 2,486.57 -6.382 6.999 7.819

0.00169595 249.75 526.16 -6.380 5.520 6.266

0.00170673 337.53 721.97 -6.373 5.822 6.582

0.00263438 344.99 738.73 -5.939 5.844 6.605

0.00271318 126.27 257.03 -5.910 4.838 5.549

0.00282061 85.42 170.48 -5.871 4.448 5.139

0.00286144 205.12 427.86 -5.856 5.324 6.059

0.00414221 3,256.12 7,808.06 -5.487 8.088 8.963

0.00414368 1,082.80 2,456.31 -5.486 6.987 7.806

0.00420110 345.22 739.25 -5.472 5.844 6.606

0.00428421 255.41 538.69 -5.453 5.543 6.289

0.00433189 204.22 425.90 -5.442 5.319 6.054

0.00690873 1,213.08 2,767.64 -4.975 7.101 7.926

0.00691392 209.53 437.53 -4.974 5.345 6.081

0.00696835 413.59 893.79 -4.966 6.025 6.795

0.00716594 252.19 531.56 -4.938 5.530 6.276

0.00716625 252.52 532.30 -4.938 5.531 6.277

0.00719254 252.19 531.55 -4.935 5.530 6.276

0.00722439 2,659.82 6,313.44 -4.930 7.886 8.750

0.01088314 672.51 1,489.38 -4.521 6.511 7.306

0.01097489 254.74 537.20 -4.512 5.540 6.286

0.01097489 254.74 537.20 -4.512 5.540 6.286

0.01117409 610.07 1,344.46 -4.494 6.414 7.204

0.01119616 414.95 896.86 -4.492 6.028 6.799

0.01147153 2,922.21 6,969.21 -4.468 7.980 8.849

0.01147253 2,929.91 6,988.51 -4.468 7.983 8.852

0.01673968 254.28 536.20 -4.090 5.538 6.285

0.01673968 254.28 536.20 -4.090 5.538 6.285

0.01748345 600.96 1,323.40 -4.047 6.399 7.188

0.01761340 600.95 1,323.36 -4.039 6.399 7.188

0.01778718 414.14 895.03 -4.029 6.026 6.797

C-52
Table C-1-3. 1980 Refinery Data (Con’t.)

----------------------- Equipment Type=DRAIN SERVICE=ALL -----------------------

Natural Natural Natural

Log of Log of TLV Log of OVA

Measured Original TLV OVA Adjusted Emission Screening Screening

Emission Screening Screening Rate Value Value

Rate(kg/hr) Value (ppmv) Value (ppmv) (kg/hr) (ppmv (ppmv

0.01794441 9,705.86 24,591.90 -4.020 9.180 10.110

0.02777731 9,675.31 24,510.60 -3.584 9.177 10.107

0.02864463 2,945.66 7,027.99 -3.553 7.988 8.858

0.04440422 2,195.64 5,161.48 -3.114 7.694 8.549

0.04565131 1,658.94 3,845.08 -3.087 7.414 8.255

0.11170747 2,216.10 5,212.02 -2.192 7.704 8.559

0.11520974 9,757.82 24,730.22 -2.161 9.186 10.116

0.28962977 9,643.68 24,426.45 -1.239 9.174 10.103

0.28962977 9,643.68 24,426.45 -1.239 9.174 10.103

0.28965511 9,669.08 24,494.01 -1.239 9.177 10.106

0.43111208 2,966.41 7,079.99 -0.841 7.995 8.865

0.43111208 2,966.41 7,079.99 -0.841 7.995 8.865

1.12802623 9,741.28 24,686.17 0.120 9.184 10.114

1.14068097 9,753.65 24,719.09 0.132 9.185 10.115

1.77893548 9,735.45 24,670.65 0.576 9.184 10.113

1.78553430 9,735.29 24,670.24 0.580 9.184 10.113

N = 61

C-53
Table C-1-3. 1980 Refinery Data (Con’t.)

------------------------ Equipment Type=PUMP SERVICE=HL ------------------------

Natural Natural Natural

Log of Log of TLV Log of OVA

Measured Original TLV OVA Adjusted Emission Screening Screening

Emission Screening Screening Rate Value Value

Rate(kg/hr) Value (ppmv) Value (ppmv) (kg/hr) (ppmv (ppmv

0.00002962 8.11 14.37 -10.427 2.093 2.665

0.00003944 90.04 180.18 -10.141 4.500 5.194

0.00015933 330.36 705.88 -8.745 5.800 6.559

0.00030611 115.55 234.17 -8.092 4.750 5.456

0.00043153 181.88 377.09 -7.748 5.203 5.932

0.00043691 711.47 1,580.13 -7.736 6.567 7.365

0.00044418 712.29 1,582.04 -7.719 6.568 7.366

0.00044597 198.46 413.29 -7.715 5.291 6.024

0.00089174 257.29 542.85 -7.022 5.550 6.297

0.00121225 713.23 1,584.25 -6.715 6.570 7.368

0.00121225 713.23 1,584.25 -6.715 6.570 7.368

0.00121559 714.87 1,588.07 -6.713 6.572 7.370

0.00121579 607.33 1,338.12 -6.712 6.409 7.199

0.00125953 913.98 2,055.71 -6.677 6.818 7.628

0.00168810 3,960.24 9,590.69 -6.384 8.284 9.169

0.00178173 710.83 1,578.63 -6.330 6.566 7.364

0.00180113 846.36 1,896.25 -6.319 6.741 7.548

0.00183552 1,188.93 2,709.80 -6.300 7.081 7.905

0.00242435 789.16 1,761.85 -6.022 6.671 7.474

0.00244487 661.26 1,463.22 -6.014 6.494 7.288

0.00245776 844.47 1,891.79 -6.009 6.739 7.545

0.00250471 1,176.77 2,680.70 -5.990 7.071 7.894

0.00251852 1,179.48 2,687.17 -5.984 7.073 7.896

0.00345651 916.25 2,061.05 -5.667 6.820 7.631

0.00479664 10,438.79 26,546.18 -5.340 9.253 10.187

0.00481697 2,376.33 5,608.57 -5.336 7.773 8.632

0.00483651 648.56 1,433.70 -5.332 6.475 7.268

0.00697471 504.98 1,102.31 -4.965 6.225 7.005

0.00962437 425.60 921.06 -4.643 6.053 6.826

0.00978532 392.28 845.47 -4.627 5.972 6.740

0.00986119 10,464.10 26,613.82 -4.619 9.256 10.189

0.00986121 10,440.11 26,549.72 -4.619 9.253 10.187

0.00995942 1,982.33 4,636.09 -4.609 7.592 8.442

0.00996275 1,422.56 3,271.75 -4.609 7.260 8.093

0.01438591 4,733.39 11,566.60 -4.242 8.462 9.356

0.01931711 3,127.43 7,484.21 -3.947 8.048 8.921

0.01950717 10,513.52 26,745.84 -3.937 9.260 10.194

0.01966882 10,513.54 26,745.91 -3.929 9.260 10.194

0.01970286 1,861.25 4,339.10 -3.927 7.529 8.375

0.02633481 506.84 1,106.58 -3.637 6.228 7.009

0.02731456 3,677.22 8,872.08 -3.600 8.210 9.091

0.02754090 3,681.46 8,882.81 -3.592 8.211 9.092

0.02775928 5,249.27 12,894.31 -3.584 8.566 9.465

0.02815822 199.52 415.60 -3.570 5.296 6.030

0.02818559 1,184.04 2,698.10 -3.569 7.077 7.900

C-54
Table C-1-3. 1980 Refinery Data (Con’t.)

Natural Natural Natural

Log of Log of TLV Log of OVA

Measured Original TLV OVA Adjusted Emission Screening Screening

Emission Screening Screening Rate Value Value

Rate(kg/hr) Value (ppmv) Value (ppmv) (kg/hr) (ppmv (ppmv

0.02842387 1,003.61 2,267.96 -3.561 6.911 7.727

0.02850212 1,003.61 2,267.96 -3.558 6.911 7.727

0.02850212 1,004.76 2,270.70 -3.558 6.913 7.728

0.02859211 10,538.38 26,812.30 -3.555 9.263 10.197

0.02859211 10,538.38 26,812.30 -3.555 9.263 10.197

0.03691188 1,018.75 2,303.91 -3.299 6.926 7.742

0.03917114 3,092.10 7,395.43 -3.240 8.037 8.909

0.03955608 10,526.89 26,781.58 -3.230 9.262 10.195

0.05258516 2,621.03 6,216.74 -2.945 7.871 8.735

0.05616945 2,837.15 6,756.30 -2.879 7.951 8.818

0.07550022 10,588.68 26,946.74 -2.584 9.268 10.202

0.11098012 9,451.61 23,915.68 -2.198 9.154 10.082

0.11374890 10,589.44 26,948.76 -2.174 9.268 10.202

0.15479117 10,565.72 26,885.35 -1.866 9.265 10.199

0.30036837 10,506.45 26,726.96 -1.203 9.260 10.193

0.30369119 10,518.53 26,759.24 -1.192 9.261 10.195

N = 61

C-55
Table C-1-3. 1980 Refinery Data (Con’t.)

------------------- Equipment Type=P_CS_PRV SERVICE=LL_G_TPS -------------------

Natural Natural Natural

Log of Log of TLV Log of OVA

Measured Original TLV OVA Adjusted Emission Screening Screening

Emission Screening Screening Rate Value Value

Rate(kg/hr) Value (ppmv) Value (ppmv) (kg/hr) (ppmv (ppmv

0.00004237 3,392.48 8,151.87 -10.069 8.129 9.006

0.00006298 136.58 279.12 -9.673 4.917 5.632

0.00006364 1,886.21 4,400.25 -9.662 7.542 8.389

0.00006397 1,534.24 3,542.06 -9.657 7.336 8.172

0.00010622 170.88 353.17 -9.150 5.141 5.867

0.00016673 3,408.70 8,192.83 -8.699 8.134 9.011

0.00017201 594.94 1,309.46 -8.668 6.388 7.177

0.00041408 374.65 805.59 -7.789 5.926 6.692

0.00041408 374.65 805.59 -7.789 5.926 6.692

0.00042163 1,089.97 2,473.39 -7.771 6.994 7.813

0.00043552 35.08 66.94 -7.739 3.558 4.204

0.00068080 268.97 568.78 -7.292 5.595 6.343

0.00068243 193.58 402.61 -7.290 5.266 5.998

0.00104082 3,463.88 8,332.20 -6.868 8.150 9.028

0.00105002 1,716.27 3,984.79 -6.859 7.448 8.290

0.00105273 1,205.32 2,749.04 -6.856 7.094 7.919

0.00105947 3,814.46 9,220.20 -6.850 8.247 9.129

0.00106711 24.55 46.02 -6.843 3.201 3.829

0.00107106 24.55 46.02 -6.839 3.201 3.829

0.00108841 431.13 933.64 -6.823 6.066 6.839

0.00108885 245.52 516.81 -6.823 5.503 6.248

0.00167903 970.51 2,189.47 -6.390 6.878 7.691

0.00170760 1,207.89 2,755.21 -6.373 7.097 7.921

0.00173961 431.38 934.21 -6.354 6.067 6.840

0.00254547 685.07 1,518.60 -5.973 6.530 7.326

0.00259400 4,915.33 12,034.08 -5.955 8.500 9.395

0.00259443 1,742.04 4,047.66 -5.954 7.463 8.306

0.00263011 15,437.18 40,039.38 -5.941 9.645 10.598

0.00264161 3,073.11 7,347.73 -5.936 8.030 8.902

0.00268912 1,216.00 2,774.64 -5.919 7.103 7.928

0.00271908 1,216.01 2,774.68 -5.907 7.103 7.928

0.00272186 383.07 824.63 -5.906 5.948 6.715

0.00399588 13,479.04 34,722.28 -5.522 9.509 10.455

0.00405129 1,224.09 2,794.03 -5.509 7.110 7.935

0.00406909 3,070.07 7,340.09 -5.504 8.029 8.901

0.00416407 34,171.65 92,254.02 -5.481 10.439 11.432

0.00423609 1,952.06 4,561.75 -5.464 7.577 8.425

0.00423609 1,952.06 4,561.75 -5.464 7.577 8.425

0.00641761 549.40 1,204.39 -5.049 6.309 7.094

0.00646354 11,933.39 30,552.46 -5.042 9.387 10.327

0.00655481 1,738.73 4,039.58 -5.028 7.461 8.304

0.00656223 2,472.04 5,846.08 -5.026 7.813 8.674

0.00656741 6,115.18 15,137.41 -5.026 8.719 9.625

0.00658649 6,816.89 16,967.08 -5.023 8.827 9.739

0.00665525 34,348.91 92,756.76 -5.012 10.444 11.438

C-56
Table C-1-3. 1980 Refinery Data (Con’t.)

------------------- Equipment Type=P_CS_PRV SERVICE=LL_G_TPS -------------------

(continued)

Natural Natural Natural

Log of Log of TLV Log of OVA

Measured Original TLV OVA Adjusted Emission Screening Screening

Emission Screening Screening Rate Value Value

Rate(kg/hr) Value (ppmv) Value (ppmv) (kg/hr) (ppmv (ppmv

0.00672364 3,057.93 7,309.60 -5.002 8.025 8.897

0.00673458 18,598.42 48,693.93 -5.001 9.831 10.793

0.00679853 3,057.97 7,309.71 -4.991 8.026 8.897

0.00684900 3,053.32 7,298.03 -4.984 8.024 8.895

0.00690833 1,550.34 3,581.13 -4.975 7.346 8.183

0.01031255 158.23 325.77 -4.574 5.064 5.786

0.01036867 11,977.05 30,669.89 -4.569 9.391 10.331

0.01058991 3,017.82 7,208.93 -4.548 8.012 8.883

0.01085059 17,055.40 44,459.47 -4.524 9.744 10.702

0.01088011 1,544.12 3,566.03 -4.521 7.342 8.179

0.01088011 1,544.12 3,566.03 -4.521 7.342 8.179

0.01580135 18,934.25 49,617.93 -4.148 9.849 10.812

0.01593600 776.04 1,731.11 -4.139 6.654 7.457

0.01650647 34,388.01 92,867.66 -4.104 10.445 11.439

0.01656751 34,388.09 92,867.88 -4.100 10.445 11.439

0.01689730 3,810.16 9,209.28 -4.081 8.245 9.128

0.01692011 24,077.03 63,863.87 -4.079 10.089 11.065

0.01719892 1,535.57 3,545.31 -4.063 7.337 8.173

0.01719892 1,535.57 3,545.31 -4.063 7.337 8.173

0.02585373 3,477.82 8,367.42 -3.655 8.154 9.032

0.02593482 17,205.09 44,869.44 -3.652 9.753 10.712

0.02608028 60,696.69 168,680.19 -3.647 11.014 12.036

0.02608058 60,603.82 168,409.10 -3.647 11.012 12.034

0.02627388 60,604.52 168,411.13 -3.639 11.012 12.034

0.02639205 1,560.08 3,604.77 -3.635 7.352 8.190

0.02646313 4,937.17 12,090.24 -3.632 8.505 9.400

0.02686162 1,747.13 4,060.09 -3.617 7.466 8.309

0.02686725 21,446.53 56,555.63 -3.617 9.973 10.943

0.02690520 305.39 649.94 -3.615 5.722 6.477

0.02699393 2,453.79 5,800.75 -3.612 7.805 8.666

0.02749516 6,829.08 16,998.96 -3.594 8.829 9.741

0.02757885 34,200.07 92,334.61 -3.591 10.440 11.433

0.02757885 34,200.07 92,334.61 -3.591 10.440 11.433

0.02768154 34,095.81 92,038.95 -3.587 10.437 11.430

0.02778396 34,095.89 92,039.17 -3.583 10.437 11.430

0.02780143 6,829.17 16,999.20 -3.583 8.829 9.741

0.02813742 6,005.66 14,852.78 -3.571 8.700 9.606

0.02824146 6,005.69 14,852.85 -3.567 8.700 9.606

0.03877057 30,226.79 81,100.81 -3.250 10.316 11.303

0.03927627 8,464.05 21,297.97 -3.237 9.044 9.966

0.03996025 6,008.29 14,859.61 -3.220 8.701 9.606

0.03999937 690.59 1,531.47 -3.219 6.538 7.334

0.04005716 54,394.88 150,333.83 -3.217 10.904 11.921

0.04060862 38,084.57 103,381.36 -3.204 10.548 11.546

C-57
Table C-1-3. 1980 Refinery Data (Con’t.)

------------------- Equipment Type=P_CS_PRV SERVICE=LL_G_TPS -------------------

(continued)

Natural Natural Natural

Log of Log of TLV Log of OVA

Measured Original TLV OVA Adjusted Emission Screening Screening

Emission Screening Screening Rate Value Value

Rate(kg/hr) Value (ppmv) Value (ppmv) (kg/hr) (ppmv (ppmv

0.04060908 38,026.29 103,215.21 -3.204 10.546 11.545

0.04187031 11,943.02 30,578.34 -3.173 9.388 10.328

0.04256917 9,349.99 23,645.64 -3.157 9.143 10.071

0.04256917 9,349.99 23,645.64 -3.157 9.143 10.071

0.04283001 2,432.76 5,748.56 -3.151 7.797 8.657

0.04283051 2,429.05 5,739.33 -3.151 7.795 8.655

0.06487572 24,414.57 64,804.64 -2.735 10.103 11.079

0.06532933 42,937.13 117,260.65 -2.728 10.667 11.672

0.06538471 38,223.99 103,778.94 -2.727 10.551 11.550

0.06581353 42,937.52 117,261.79 -2.721 10.668 11.672

0.06772129 3,881.55 9,390.62 -2.692 8.264 9.147

0.06798752 494.31 1,077.85 -2.688 6.203 6.983

0.06842301 4,313.78 10,492.02 -2.682 8.370 9.258

0.06849158 494.31 1,077.86 -2.681 6.203 6.983

0.06997327 2,509.90 5,940.16 -2.660 7.828 8.689

0.06997569 2,498.40 5,911.58 -2.660 7.823 8.685

0.09915559 42,959.58 117,325.05 -2.311 10.668 11.673

0.10025896 43,025.90 117,515.33 -2.300 10.670 11.674

0.10120459 4,296.13 10,446.92 -2.291 8.365 9.254

0.10206861 77,307.92 217,480.42 -2.282 11.256 12.290

0.10232039 1,581.97 3,657.91 -2.280 7.366 8.205

0.10262666 60,707.73 168,712.42 -2.277 11.014 12.036

0.10331044 1,930.11 4,507.88 -2.270 7.565 8.414

0.10338849 60,615.54 168,443.32 -2.269 11.012 12.034

0.10383965 12,085.32 30,961.16 -2.265 9.400 10.340

0.10462156 54,460.17 150,523.39 -2.257 10.905 11.922

0.10462397 54,293.77 150,040.32 -2.257 10.902 11.919

0.10699986 6,851.16 17,056.70 -2.235 8.832 9.744

0.10931033 7,637.50 19,118.82 -2.214 8.941 9.858

0.15847552 43,182.52 117,964.71 -1.842 10.673 11.678

0.15898465 76,643.97 215,518.87 -1.839 11.247 12.281

0.16951073 3,042.23 7,270.20 -1.775 8.020 8.892

0.25840755 7,645.71 19,140.43 -1.353 8.942 9.860

0.26302874 3,067.28 7,333.09 -1.335 8.029 8.900

0.26527004 12,081.00 30,949.56 -1.327 9.399 10.340

0.42981364 3,073.86 7,349.62 -0.844 8.031 8.902

1.10801132 30,774.57 82,645.36 0.103 10.334 11.322

1.10801132 30,774.57 82,645.36 0.103 10.334 11.322

1.12449932 30,775.07 82,646.76 0.117 10.334 11.322

N = 128

C-58
Table C-1-3. 1980 Refinery Data (Con’t.)

------------------------ Equipment Type=VALVE SERVICE=G ------------------------

Natural Natural Natural

Log of Log of TLV Log of OVA

Measured Original TLV OVA Adjusted Emission Screening Screening

Emission Screening Screening Rate Value Value

Rate(kg/hr) Value (ppmv) Value (ppmv) (kg/hr) (ppmv (ppmv

0.00001331 88.91 177.82 -11.227 4.488 5.181

0.00004011 6,639.19 16,502.81 -10.124 8.801 9.711

0.00005873 1,100.81 2,499.23 -9.743 7.004 7.824

0.00008684 28,723.41 76,869.15 -9.351 10.265 11.250

0.00008847 273.72 579.32 -9.333 5.612 6.362

0.00008852 82.39 164.13 -9.332 4.411 5.101

0.00012745 2,159.55 5,072.40 -8.968 7.678 8.532

0.00026556 4,000.01 9,691.89 -8.234 8.294 9.179

0.00037361 4,327.05 10,525.93 -7.892 8.373 9.262

0.00053159 2,786.15 6,628.77 -7.540 7.932 8.799

0.00056183 9,364.08 23,683.07 -7.484 9.145 10.073

0.00056516 9,364.16 23,683.30 -7.478 9.145 10.073

0.00077033 9,401.02 23,781.23 -7.169 9.149 10.077

0.00079547 3,094.87 7,402.39 -7.137 8.038 8.910

0.00111849 2,001.89 4,684.16 -6.796 7.602 8.452

0.00163767 10,341.06 26,285.19 -6.414 9.244 10.177

0.00164080 8,596.21 21,647.44 -6.413 9.059 9.983

0.00164247 10,364.87 26,348.78 -6.412 9.246 10.179

0.00230073 40,320.51 109,766.16 -6.075 10.605 11.606

0.00230829 3,972.31 9,621.40 -6.071 8.287 9.172

0.00329738 17,115.36 44,623.65 -5.715 9.748 10.706

0.00335895 87,956.92 249,053.14 -5.696 11.385 12.425

0.00339793 67,782.41 189,423.49 -5.685 11.124 12.152

0.00479241 4,409.66 10,737.12 -5.341 8.392 9.281

0.00525603 22,456.91 59,357.68 -5.248 10.019 10.991

0.00740749 48,426.60 133,057.03 -4.905 10.788 11.799

0.01034094 62,802.08 174,831.53 -4.572 11.048 12.072

0.01097916 57,627.00 159,730.80 -4.512 10.962 11.981

0.01099118 29,275.75 78,422.59 -4.511 10.285 11.270

0.01504923 44,686.05 122,282.85 -4.196 10.707 11.714

0.01514346 57,523.86 159,430.51 -4.190 10.960 11.979

0.01518837 57,458.07 159,238.97 -4.187 10.959 11.978

0.03115510 15,704.60 40,768.29 -3.469 9.662 10.616

0.04884917 10,348.47 26,304.97 -3.019 9.245 10.178

0.09161977 17,363.25 45,302.80 -2.390 9.762 10.721

0.09853946 44,817.44 122,660.53 -2.317 10.710 11.717

0.13483362 41,140.73 112,112.87 -2.004 10.625 11.627

0.13594593 10,484.70 26,668.84 -1.995 9.258 10.191

N = 38

C-59
Table C-1-3. 1980 Refinery Data (Con’t.)

--------------------- Equipment Type=VALVE SERVICE=LL_TPS ----------------------

Natural Natural Natural

Log of Log of TLV Log of OVA

Measured Original TLV OVA Adjusted Emission Screening Screening

Emission Screening Screening Rate Value Value

Rate(kg/hr) Value (ppmv) Value (ppmv) (kg/hr) (ppmv (ppmv

0.00000225 4.59 7.91 -13.007 1.525 2.068

0.00001410 44.59 86.11 -11.170 3.797 4.456

0.00005956 62.56 122.91 -9.729 4.136 4.811

0.00008638 156.77 322.62 -9.357 5.055 5.776

0.00012792 21.47 39.97 -8.964 3.067 3.688

0.00012930 209.02 436.41 -8.953 5.342 6.079

0.00013197 305.66 650.53 -8.933 5.722 6.478

0.00018238 620.52 1,368.68 -8.609 6.431 7.222

0.00018238 620.52 1,368.68 -8.609 6.431 7.222

0.00018799 22.13 41.25 -8.579 3.097 3.720

0.00019149 84.34 168.23 -8.561 4.435 5.125

0.00026364 64.62 127.17 -8.241 4.169 4.846

0.00027025 976.13 2,202.77 -8.216 6.884 7.697

0.00027125 5,330.54 13,104.08 -8.212 8.581 9.481

0.00039603 484.14 1,054.57 -7.834 6.182 6.961

0.00056453 1,162.25 2,645.96 -7.480 7.058 7.881

0.00060409 9,829.56 24,921.22 -7.412 9.193 10.123

0.00075854 8,440.85 21,236.66 -7.184 9.041 9.963

0.00082319 10.05 18.01 -7.102 2.308 2.891

0.00083585 984.52 2,222.66 -7.087 6.892 7.706

0.00085249 3,206.69 7,683.59 -7.067 8.073 8.947

0.00113007 1,153.61 2,625.30 -6.785 7.051 7.873

0.00118193 10.03 17.96 -6.741 2.305 2.888

0.00120220 3,324.54 7,980.47 -6.724 8.109 8.985

0.00123419 9,979.00 25,319.36 -6.697 9.208 10.139

0.00163290 4,540.59 11,072.23 -6.417 8.421 9.312

0.00168838 1,363.36 3,128.89 -6.384 7.218 8.048

0.00170950 1,796.41 4,180.46 -6.372 7.494 8.338

0.00179606 3,953.18 9,572.75 -6.322 8.282 9.167

0.00241099 5,398.93 13,280.75 -6.028 8.594 9.494

0.00241192 860.44 1,929.39 -6.027 6.757 7.565

0.00243467 3,361.20 8,072.96 -6.018 8.120 8.996

0.00247077 3,354.55 8,056.16 -6.003 8.118 8.994

0.00247366 8,515.22 21,433.26 -6.002 9.050 9.973

0.00248176 3,998.89 9,689.06 -5.999 8.294 9.179

0.00249558 8,515.54 21,434.09 -5.993 9.050 9.973

0.00255458 1,013.43 2,291.28 -5.970 6.921 7.737

0.00341580 39,058.18 106,159.28 -5.679 10.573 11.573

0.00348074 33,787.34 91,164.47 -5.661 10.428 11.420

0.00349794 54,274.02 149,982.99 -5.656 10.902 11.918

0.00353072 8,527.25 21,465.06 -5.646 9.051 9.974

0.00353574 30,014.01 80,501.23 -5.645 10.309 11.296

0.00355244 1,381.43 3,172.46 -5.640 7.231 8.062

0.00357339 1,381.46 3,172.54 -5.634 7.231 8.062

0.00357551 15,739.47 40,863.36 -5.634 9.664 10.618

C-60
Table C-1-3. 1980 Refinery Data (Con’t.)

--------------------- Equipment Type=VALVE SERVICE=LL_TPS ----------------------

(continued)

Natural Natural Natural

Log of Log of TLV Log of OVA

Measured Original TLV OVA Adjusted Emission Screening Screening

Emission Screening Screening Rate Value Value

Rate(kg/hr) Value (ppmv) Value (ppmv) (kg/hr) (ppmv (ppmv

0.00485006 8,625.65 21,725.33 -5.329 9.062 9.986

0.00491615 3,398.24 8,166.42 -5.315 8.131 9.008

0.00491615 3,398.24 8,166.42 -5.315 8.131 9.008

0.00493071 3,391.35 8,149.01 -5.312 8.129 9.006

0.00495259 1,383.25 3,176.85 -5.308 7.232 8.064

0.00516794 9,994.91 25,361.77 -5.265 9.210 10.141

0.00729950 8,551.85 21,530.11 -4.920 9.054 9.977

0.00736431 8,534.69 21,484.75 -4.911 9.052 9.975

0.00739766 1,176.57 2,680.21 -4.907 7.070 7.894

0.00755167 86,029.82 243,324.55 -4.886 11.362 12.402

0.00758374 2,932.48 6,994.95 -4.882 7.984 8.853

0.00758440 24,845.17 66,005.77 -4.882 10.120 11.097

0.00759940 13,655.17 35,199.01 -4.880 9.522 10.469

0.00772423 5,502.03 13,547.27 -4.863 8.613 9.514

0.01046618 86,317.33 244,178.82 -4.560 11.366 12.406

0.01047971 73,754.07 206,991.10 -4.558 11.208 12.240

0.01060438 8,547.05 21,517.41 -4.546 9.053 9.977

0.01066692 8,547.24 21,517.93 -4.541 9.053 9.977

0.01079315 8,547.64 21,518.97 -4.529 9.053 9.977

0.01127245 6,475.35 16,075.28 -4.485 8.776 9.685

0.01166120 5,355.65 13,168.93 -4.451 8.586 9.486

0.01474084 8,540.75 21,500.76 -4.217 9.053 9.976

0.01570609 29,161.44 78,100.99 -4.154 10.281 11.266

0.01605400 24,817.50 65,928.55 -4.132 10.119 11.096

0.02334577 7,507.70 18,777.67 -3.757 8.924 9.840

0.02368390 5,459.20 13,436.52 -3.743 8.605 9.506

0.02368390 5,459.20 13,436.52 -3.743 8.605 9.506

0.03207526 21,746.78 57,387.63 -3.440 9.987 10.958

0.04684899 47,238.27 129,629.48 -3.061 10.763 11.772

0.06870371 62,845.47 174,958.43 -2.678 11.048 12.072

0.10218383 62,944.53 175,248.12 -2.281 11.050 12.074

0.13512360 62,501.44 173,952.50 -2.002 11.043 12.067

N = 77

C-61
Table C-1-3. 1980 Refinery Data (Con’t.)

---------------------- Equipment Type=V_CS SERVICE=HYDRO -----------------------

Natural Natural Natural

Log of Log of TLV Log of OVA

Measured Original TLV OVA Adjusted Emission Screening Screening

Emission Screening Screening Rate Value Value

Rate(kg/hr) Value (ppmv) Value (ppmv) (kg/hr) (ppmv (ppmv

0.00000026 499.50 1,089.76 -15.164 6.214 6.994

0.00001464 33,440.21 90,180.89 -11.132 10.418 11.410

0.00002100 354.70 760.60 -10.771 5.871 6.634

0.00002104 1,197.44 2,730.17 -10.769 7.088 7.912

0.00002118 1,974.09 4,615.83 -10.762 7.588 8.437

0.00002933 33,494.85 90,335.66 -10.437 10.419 11.411

0.00003021 7,191.76 17,948.51 -10.407 8.881 9.795

0.00004536 253.47 534.39 -10.001 5.535 6.281

0.00012180 28,416.27 76,005.97 -9.013 10.255 11.239

0.00012180 28,416.27 76,005.97 -9.013 10.255 11.239

0.00012252 28,416.66 76,007.07 -9.007 10.255 11.239

0.00018123 95,583.08 271,783.91 -8.616 11.468 12.513

0.00025613 95,116.75 270,391.26 -8.270 11.463 12.508

0.00026043 4,052.53 9,825.60 -8.253 8.307 9.193

0.00041109 141.22 289.09 -7.797 4.950 5.667

0.00054874 95,287.08 270,899.89 -7.508 11.465 12.510

0.00056055 3,638.51 8,773.98 -7.487 8.199 9.080

0.00110337 28,727.31 76,880.12 -6.809 10.266 11.250

0.00110661 28,727.51 76,880.68 -6.806 10.266 11.250

0.00111311 28,727.91 76,881.80 -6.801 10.266 11.250

0.00118994 1,204.72 2,747.61 -6.734 7.094 7.918

0.00170959 10,318.68 26,225.43 -6.371 9.242 10.174

0.00235967 8,602.88 21,665.09 -6.049 9.060 9.983

0.00509039 94,269.02 267,860.46 -5.280 11.454 12.498

0.00706640 95,751.81 272,287.91 -4.952 11.470 12.515

0.00710793 95,753.13 272,291.86 -4.947 11.470 12.515

0.00712880 95,753.80 272,293.84 -4.944 11.470 12.515

0.01037369 95,729.11 272,220.09 -4.568 11.469 12.514

0.01040414 95,729.77 272,222.06 -4.566 11.469 12.514

0.01046548 95,621.82 271,899.63 -4.560 11.468 12.513

0.01049601 95,731.75 272,227.99 -4.557 11.469 12.514

0.01559018 95,711.47 272,167.42 -4.161 11.469 12.514

0.02089894 95,777.39 272,364.32 -3.868 11.470 12.515

0.02102181 95,778.71 272,368.27 -3.862 11.470 12.515

0.02114537 95,780.04 272,372.22 -3.856 11.470 12.515

0.02120783 95,671.37 272,047.64 -3.853 11.469 12.514

0.02133247 95,672.91 272,052.24 -3.848 11.469 12.514

0.03262723 95,877.79 272,664.22 -3.423 11.471 12.516

0.03337807 10,367.31 26,355.28 -3.400 9.246 10.179

0.04530855 95,188.17 270,604.54 -3.094 11.464 12.508

0.04570873 95,190.15 270,610.43 -3.085 11.464 12.508

0.04584365 95,082.37 270,288.60 -3.083 11.462 12.507

0.06482435 29,370.14 78,688.21 -2.736 10.288 11.273

0.06483958 74,453.14 209,052.45 -2.736 11.218 12.250

0.06535400 95,270.18 270,849.44 -2.728 11.464 12.509

C-62
Table C-1-3. 1980 Refinery Data (Con’t.)

---------------------- Equipment Type=V_CS SERVICE=HYDRO -----------------------

(continued)

Natural Natural Natural

Log of Log of TLV Log of OVA

Measured Original TLV OVA Adjusted Emission Screening Screening

Emission Screening Screening Rate Value Value

Rate(kg/hr) Value (ppmv) Value (ppmv) (kg/hr) (ppmv (ppmv

0.06612569 95,164.29 270,533.21 -2.716 11.463 12.508

0.06612569 95,164.29 270,533.21 -2.716 11.463 12.508

N = 47

C-63
Table C-1-4. REGRESSION STATISTICS FOR THE 1980 AND 1993 REFINERY 

Equipment

Facility

Typea

Sample

Size

Intercept

(b

0)

Slope

(b1)

Root

Mean

Square

Error

(RMSE)

Coefficient of

Simple

Determination

(R

2)

Scale Bias

Correctio

n Factor

(SBCF)

Me

Scr

V

Type Service

Connector All

REF80 38 -12.07497 0.759 1.011 0.5333 1.6334 6.6REF93 28 -17.45599 1.007 1.851 0.7233 4.7774 7.0

Pump Light Liquid

b

REF80 128 -10.02998 0.676 1.726 0.3371 4.3133 8.3REF93 30 -10.07607 0.419 1.579 0.3281 3.1882 6.7

Valve Gas

REF80 38 -14.93176 0.960 1.751 0.4788 4.2109 9.1REF93 50 -13.94624 0.675 1.245 0.5725 2.1124 6.2

Valve Light Liquidc REF80 77 -11.46481 0.678 1.230 0.6145 2.0935 7.9

REF93 82 -14.17854 0.783 1.453 0.6340 2.7995 6.5

aFacility types are: REF80=1980 refinery data and REF93=1993 refinery databFor light liquid pumps, the 1980 refinery data include two-phase stream p

compressors, gas pressure relief valves, and light liquid pumps.

cFor light liquid valves, the 1980 refinery data include two-phase stream 

light liquid valves.

C-64
APPENDIX C: ATTACHMENT 2

This attachment lists the bagging data used to develop the

pegged emission rates for the combined 1993 petroleum industry

data in table C-2-1. Table C-2-2 lists summary statistics for

the 10,000 ppmv pegged emission rates and Table C-2-3 lists

summary statistics for the 100,000 ppmv pegged emission rates.

C-65
TABLE C-2-1. BAGGING DATA USED TO DEVELOP PEGGED EMISSION RATES

Natural

Initial Final Log of

Screening Screening Measured Emission

Plant Value Value Emission Rate

Type (ppmv) (ppmv) Rate(kg/hr) (kg/hr)

--------- Equipment Type=COMPRESSOR SERVICE=G ----------

ONOFF 100000 100000 0.02448289939 -3.710

ONOFF 100000 100000 0.03493150685 -3.354

N=2

---------- Equipment Type=COMPRESSOR SERVICE=LL -----------

ONOFF 100000 100000 0.00101197496 -6.896

N=1

----------- Equipment Type=CONNECTOR SERVICE=G -----------

ONOFF 5000 10000 0.00001270072 -11.274

ONOFF 70000 70000 0.00009344099 -9.278

ONOFF 10000 10000 0.00015104781 -8.798

REF 100000 100000 0.00019804046 -8.527

ONOFF 100000 100000 0.00031933231 -8.049

MT 100000 100000 0.00035811031 -7.935

ONOFF 100000 100000 0.00045858659 -7.687

ONOFF 100000 100000 0.00081556745 -7.112

REF 11000 11000 0.00094198494 -6.968

REF 91000 91000 0.00125365146 -6.682

REF 100000 100000 0.00199886601 -6.215

REF 48000 40000 0.00220312075 -6.118

MT 100000 100000 0.00277519731 -5.887

ONOFF 10000 10000 0.00287262996 -5.853

ONOFF 10000 10000 0.00291935045 -5.836

ONOFF 100000 45000 0.00297922526 -5.816

ONOFF 100000 100000 0.00371632042 -5.595

ONOFF 10000 100000 0.00515513018 -5.268

ONOFF 10000 10000 0.00559920167 -5.185

ONOFF 100000 100000 0.00675269890 -4.998

ONOFF 100000 100000 0.00760364692 -4.879

ONOFF 100000 100000 0.00877029847 -4.736

ONOFF 100000 100000 0.01064229339 -4.543

ONOFF 100000 100000 0.01651047809 -4.104

REF 100000 100000 0.02005624603 -3.909

ONOFF 10000 10000 0.03374716502 -3.389

REF 100000 100000 0.03482899392 -3.357

REF 12500 29000 0.03548852400 -3.339

REF 55000 55000 0.05391454232 -2.920

C-66
Table C-2-1. BAGGING DATA USED TO DEVELOP PEGGED EMISSION RATES

(CONTINUED)

Natural

Initial Final Log of

Screening Screening Measured Emission

Plant Value Value Emission Rate

Type (ppmv) (ppmv) Rate(kg/hr) (kg/hr)

ONOFF 100000 100000 0.06664383562 -2.708

ONOFF 100000 100000 0.10322462125 -2.271

N = 31

----------- Equipment Type=CONNECTOR SERVICE=HL -----------

REF 76650 21900 0.01362968339 -4.296

REF 1700 1200 0.03207475279 -3.440

N=2

----------- Equipment Type=CONNECTOR SERVICE=LL -----------

ONOFF 100000 100000 0.00000408237 -12.409

ONOFF 10000 5000 0.00001859748 -10.892

REF 21060 17550 0.00001880613 -10.881

ONOFF 10000 10000 0.00002494784 -10.599

REF 16500 27500 0.00006329946 -9.668

ONOFF 10000 10000 0.00006441078 -9.650

ONOFF 100000 100000 0.00010977048 -9.117

ONOFF 10000 10000 0.00027215821 -8.209

ONOFF 100000 100000 0.00038328949 -7.867

ONOFF 100000 100000 0.00040143337 -7.820

REF 48000 100000 0.00062002177 -7.386

ONOFF 10000 10000 0.00063594303 -7.360

REF 90000 90000 0.00082713417 -7.098

ONOFF 100000 100000 0.00088768938 -7.027

ONOFF 10000 10000 0.00092760591 -6.983

REF 72000 80000 0.00117463485 -6.747

REF 117000 117000 0.00119817654 -6.727

ONOFF 4000 10000 0.00153451873 -6.480

ONOFF 10000 10000 0.00185475823 -6.290

ONOFF 100000 100000 0.00198267259 -6.223

ONOFF 10000 10000 0.00259548217 -5.954

REF 100000 100000 0.00275909462 -5.893

REF 47000 47000 0.00283806586 -5.865

REF 117000 117000 0.00303991654 -5.796

REF 49700 56000 0.00337970607 -5.690

ONOFF 10000 10000 0.00383470924 -5.564

ONOFF 5000 10000 0.00396035562 -5.531

ONOFF 100000 50000 0.00445613717 -5.413

ONOFF 100000 100000 0.00489748707 -5.319

ONOFF 100000 100000 0.00597387281 -5.120

REF 90000 90000 0.00711648372 -4.945

ONOFF 10000 10000 0.01034019777 -4.572

ONOFF 100000 100000 0.01055701715 -4.551

C-67
Table C-2-1. BAGGING DATA USED TO DEVELOP PEGGED EMISSION RATES

(CONTINUED)

Natural

Initial Final Log of

Screening Screening Measured Emission

Plant Value Value Emission Rate

Type (ppmv) (ppmv) Rate(kg/hr) (kg/hr)

ONOFF 10000 10000 0.01699718770 -4.075

REF 20000 35000 0.02082463939 -3.872

ONOFF 100000 100000 0.02084550485 -3.871

ONOFF 100000 100000 0.02378708156 -3.739

REF 66000 66000 0.02872992833 -3.550

ONOFF 100000 100000 0.05975551120 -2.817

ONOFF 100000 100000 0.07526807584 -2.587

ONOFF 40000 50000 0.15713462760 -1.851

N = 41

----------- Equipment Type=DUMP LEVER ARM SERVICE=G -----------

ONOFF 100000 100000 0.39765218180 -0.922

N=1

----------- Equipment Type=FLANGE SERVICE=G -----------

ONOFF 10000 10000 0.00000544316 -12.121

REF 86000 86000 0.00007830899 -9.455

ONOFF 10000 8000 0.00030254922 -8.103

ONOFF 4000 10000 0.00045722580 -7.690

ONOFF 100000 100000 0.00241857933 -6.025

ONOFF 10000 9000 0.00292252563 -5.835

REF 86000 86000 0.00374639390 -5.587

ONOFF 100000 90000 0.00613217817 -5.094

ONOFF 100000 100000 0.01279370407 -4.359

ONOFF 100000 100000 0.01363467296 -4.295

ONOFF 100000 100000 0.01780277601 -4.028

ONOFF 100000 100000 0.01851673773 -3.989

REF 100000 100000 0.02487798240 -3.694

ONOFF 100000 100000 0.03357615894 -3.394

ONOFF 100000 20000 0.04434137712 -3.116

ONOFF 100000 100000 0.06712600925 -2.701

ONOFF 100000 100000 0.09028894130 -2.405

ONOFF 100000 100000 0.10636124467 -2.241

N = 18

----------- Equipment Type=FLANGE SERVICE=LL -----------

ONOFF 100000 100000 0.00015603738 -8.765

REF 18000 22500 0.00095309807 -6.956

REF 30000 40000 0.00125641840 -6.679

REF 13200 9900 0.00344683843 -5.670

C-68
Table C-2-1. BAGGING DATA USED TO DEVELOP PEGGED EMISSION RATES

(CONTINUED)

Natural

Initial Final Log of

Screening Screening Measured Emission

Plant Value Value Emission Rate

Type (ppmv) (ppmv) Rate(kg/hr) (kg/hr)

ONOFF 100000 60000 0.02859657081 -3.554

ONOFF 100000 100000 0.17639481085 -1.735

N=6

----------- Equipment Type=INSTRUMENT SERVICE=G -----------

ONOFF 30000 30000 0.00028259095 -8.172

ONOFF 100000 100000 0.01809307811 -4.012

N=2

----------- Equipment Type=INSTRUMENT SERVICE=LL -----------

ONOFF 100000 100000 0.00345005897 -5.669

N=1

----------- Equipment Type=LOADARM SERVICE=G -----------

MT 100000 100000 0.00021052799 -8.466

MT 400000 400000 0.04320148780 -3.142

MT 310000 310000 0.04397804590 -3.124

MT 7200 24000 0.04716501860 -3.054

N=4

----------- Equipment Type=OEL SERVICE=G -----------

ONOFF 100000 100000 0.00000272158 -12.814

ONOFF 3000 10000 0.00001360791 -11.205

ONOFF 200 10000 0.00001769028 -10.942

ONOFF 10000 10000 0.00001814388 -10.917

ONOFF 10000 10000 0.00003039100 -10.401

REF 13400 16750 0.00004146875 -10.091

ONOFF 20000 15000 0.00004853488 -9.933

ONOFF 10000 10000 0.00005080287 -9.888

ONOFF 3000 10000 0.00007983308 -9.436

ONOFF 10000 10000 0.00008935861 -9.323

ONOFF 10000 10000 0.00009026581 -9.313

REF 100000 100000 0.00013893677 -8.881

ONOFF 9000 10000 0.00014877982 -8.813

ONOFF 10000 100000 0.00020547945 -8.490

REF 6000 10000 0.00023758051 -8.345

ONOFF 12000 15000 0.00029257008 -8.137

C-69
Table C-2-1. BAGGING DATA USED TO DEVELOP PEGGED EMISSION RATES

(CONTINUED)

Natural

Initial Final Log of

Screening Screening Measured Emission

Plant Value Value Emission Rate

Type (ppmv) (ppmv) Rate(kg/hr) (kg/hr)

ONOFF 100000 100000 0.00046901932 -7.665

ONOFF 35000 20000 0.00057652182 -7.458

ONOFF 10000 10000 0.00059194412 -7.432

ONOFF 100000 100000 0.00072167287 -7.234

REF 50000 40000 0.00087367323 -7.043

ONOFF 100000 100000 0.00094847138 -6.961

ONOFF 100000 100000 0.00100244942 -6.905

ONOFF 10000 10000 0.00142610904 -6.553

ONOFF 10000 9000 0.00148326227 -6.514

ONOFF 70000 70000 0.00203392906 -6.198

ONOFF 15000 15000 0.00229792253 -6.076

REF 119000 119000 0.00267976050 -5.922

ONOFF 100000 100000 0.00350403701 -5.654

ONOFF 40000 100000 0.00398666425 -5.525

REF 89000 89000 0.00412528350 -5.491

ONOFF 100000 100000 0.00440850948 -5.424

ONOFF 100000 100000 0.00509843055 -5.279

ONOFF 10000 10000 0.00556200671 -5.192

REF 110000 110000 0.00582781457 -5.145

ONOFF 10000 10000 0.00610314796 -5.099

ONOFF 100000 100000 0.00673001905 -5.001

ONOFF 100000 100000 0.00783997097 -4.849

ONOFF 100000 80000 0.00808309897 -4.818

ONOFF 100000 100000 0.00899074662 -4.712

REF 140000 140000 0.01182844961 -4.437

ONOFF 100000 100000 0.01357071578 -4.300

REF 140000 140000 0.01958495872 -3.933

ONOFF 100000 100000 0.02699718770 -3.612

ONOFF 100000 100000 0.04810033566 -3.034

ONOFF 100000 100000 0.05125374218 -2.971

ONOFF 100000 100000 0.05756735916 -2.855

ONOFF 100000 100000 0.06938129366 -2.668

ONOFF 100000 100000 0.15146738637 -1.887

ONOFF 100000 100000 0.19622017600 -1.629

ONOFF 100000 100000 0.72652136442 -0.319

N = 51

----------- Equipment Type=OEL SERVICE=HL -----------

ONOFF 10000 8000 0.00003991654 -10.129

REF 15000 16000 0.00018571169 -8.591

ONOFF 10000 10000 0.00264628504 -5.935

REF 700 700 0.00467341014 -5.366

N=4

C-70
Table C-2-1. BAGGING DATA USED TO DEVELOP PEGGED EMISSION RATES

(CONTINUED)

Natural

Initial Final Log of

Screening Screening Measured Emission

Plant Value Value Emission Rate

Type (ppmv) (ppmv) Rate(kg/hr) (kg/hr)

----------- Equipment Type=OEL SERVICE=LL -----------

ONOFF 20000 100000 0.00003538057 -10.249

REF 13200 16500 0.00009666606 -9.244

ONOFF 20000 3000 0.00011385285 -9.081

ONOFF 30000 40000 0.00013063594 -8.943

ONOFF 2000 10000 0.00043000998 -7.752

ONOFF 10000 8000 0.00043499955 -7.740

REF 12000 13000 0.00056373038 -7.481

ONOFF 6000 20000 0.00085366960 -7.066

REF 100000 100000 0.00085947564 -7.059

REF 14000 12000 0.00092007620 -6.991

REF 95000 100000 0.00101356255 -6.894

ONOFF 10000 1000 0.00117753788 -6.744

ONOFF 40000 35000 0.00120112492 -6.724

MT 300000 300000 0.00217168647 -6.132

ONOFF 20000 20000 0.00219268802 -6.123

MT 136000 119000 0.00292179987 -5.836

ONOFF 50000 35000 0.00361471469 -5.623

ONOFF 100000 100000 0.00493286764 -5.312

ONOFF 80000 60000 0.00594257462 -5.126

ONOFF 100000 100000 0.00672366869 -5.002

ONOFF 50000 100000 0.00678853307 -4.993

ONOFF 100000 30000 0.00804363603 -4.823

ONOFF 100000 100000 0.00847319242 -4.771

REF 20000 33600 0.00883470924 -4.729

ONOFF 10000 10000 0.00924929692 -4.683

ONOFF 10000 10000 0.01178853307 -4.441

ONOFF 100000 100000 0.01185702622 -4.435

REF 73000 73000 0.01350811939 -4.304

ONOFF 100000 100000 0.01985711694 -3.919

ONOFF 100000 100000 0.02174907013 -3.828

REF 140000 140000 0.04261680123 -3.156

ONOFF 100000 100000 0.07331080468 -2.613

N = 32

----------- Equipment Type=OTHER SERVICE=G -----------

MT 100000 100000 0.01708926789 -4.069

MT 100000 100000 0.01809353171 -4.012

N=2

----------- Equipment Type=PRV SERVICE=G -----------

ONOFF 100000 100000 0.02052209018 -3.886

C-71
Table C-2-1. BAGGING DATA USED TO DEVELOP PEGGED EMISSION RATES

(CONTINUED)

Natural

Initial Final Log of

Screening Screening Measured Emission

Plant Value Value Emission Rate

Type (ppmv) (ppmv) Rate(kg/hr) (kg/hr)

ONOFF 100000 100000 0.36418670054 -1.010

N=2

----------- Equipment Type=PUMP SERVICE=LL -----------

REF 35000 21000 0.00082055702 -7.106

REF 40500 27000 0.00086514560 -7.053

REF 109000 98100 0.00105651819 -6.853

REF 76500 90000 0.00106527261 -6.845

REF 21000 25000 0.00119445704 -6.730

MT 10000 12000 0.00176567178 -6.339

REF 56000 28000 0.00958087635 -4.648

REF 12000 16000 0.00968248208 -4.637

REF 18000 17400 0.03439081920 -3.370

REF 77000 47000 0.03876077293 -3.250

REF 100000 100000 0.16085911276 -1.827

REF 100000 100000 1.25088451420 0.224

N = 12

----------- Equipment Type=STUFFING BOX SERVICE=LL -----------

ONOFF 10000 500 0.00035698086 -7.938

ONOFF 10000 10000 0.00215186428 -6.141

N=2

----------- Equipment Type=VALVE SERVICE=G -----------

ONOFF 100000 100000 0.00000725755 -11.833

ONOFF 1000 10000 0.00001814388 -10.917

ONOFF 10000 10000 0.00002585503 -10.563

ONOFF 60000 10000 0.00002585503 -10.563

ONOFF 100000 100000 0.00002676222 -10.529

ONOFF 100000 100000 0.00004127733 -10.095

ONOFF 10000 10000 0.00005171006 -9.870

ONOFF 100000 100000 0.00005488524 -9.810

ONOFF 100000 3000 0.00008754423 -9.343

REF 20000 2000 0.00023997097 -8.335

ONOFF 100000 100000 0.00026399347 -8.240

ONOFF 10000 10000 0.00026852944 -8.223

ONOFF 15000 15000 0.00029257008 -8.137

ONOFF 100000 100000 0.00031706432 -8.056

REF 22500 22500 0.00035323415 -7.948

ONOFF 10000 10000 0.00038555747 -7.861

REF 18000 15000 0.00038567541 -7.861

C-72
Table C-2-1. BAGGING DATA USED TO DEVELOP PEGGED EMISSION RATES

(CONTINUED)

Natural

Initial Final Log of

Screening Screening Measured Emission

Plant Value Value Emission Rate

Type (ppmv) (ppmv) Rate(kg/hr) (kg/hr)

REF 65700 65700 0.00060437268 -7.411

REF 100000 100000 0.00060967976 -7.403

ONOFF 10000 10000 0.00064002540 -7.354

ONOFF 100000 100000 0.00068946748 -7.280

ONOFF 100000 20000 0.00069717863 -7.268

REF 80000 48000 0.00085747981 -7.062

ONOFF 70000 70000 0.00090220448 -7.011

ONOFF 30000 10000 0.00094166742 -6.968

ONOFF 15000 15000 0.00094484260 -6.964

ONOFF 10000 10000 0.00095799692 -6.951

ONOFF 100000 100000 0.00104644834 -6.862

ONOFF 50000 40000 0.00109815840 -6.814

ONOFF 10000 10000 0.00121291844 -6.715

ONOFF 7500 10000 0.00122335117 -6.706

REF 100000 100000 0.00128871451 -6.654

ONOFF 100000 100000 0.00128957634 -6.653

ONOFF 100000 100000 0.00133085367 -6.622

REF 100000 100000 0.00160963440 -6.432

ONOFF 40000 40000 0.00171278236 -6.370

REF 109000 109000 0.00178594756 -6.328

ONOFF 10000 10000 0.00181348090 -6.313

ONOFF 10000 10000 0.00199129094 -6.219

REF 100000 100000 0.00205130182 -6.189

ONOFF 60000 100000 0.00206341286 -6.183

ONOFF 100000 100000 0.00208563912 -6.173

ONOFF 25000 40000 0.00233194230 -6.061

ONOFF 50000 40000 0.00269255194 -5.917

MT 300000 300000 0.00277487980 -5.887

ONOFF 100000 100000 0.00287081557 -5.853

REF 67000 100000 0.00287548762 -5.852

ONOFF 100000 100000 0.00300553388 -5.807

ONOFF 100000 100000 0.00333167014 -5.704

ONOFF 100000 100000 0.00336795791 -5.693

REF 77000 77000 0.00341059603 -5.681

REF 80000 80000 0.00349872993 -5.655

ONOFF 100000 100000 0.00377438084 -5.580

REF 58000 35000 0.00417118752 -5.480

REF 100000 100000 0.00479905652 -5.339

REF 100000 100000 0.00497732015 -5.303

ONOFF 100000 100000 0.00498639209 -5.301

REF 78000 78000 0.00514197587 -5.270

ONOFF 100000 100000 0.00520366506 -5.258

ONOFF 100000 100000 0.00543227796 -5.215

ONOFF 10000 10000 0.00546720494 -5.209

REF 100000 100000 0.00554839880 -5.194

ONOFF 100000 100000 0.00594393541 -5.125

ONOFF 10000 10000 0.00630545224 -5.066

ONOFF 100000 100000 0.00660664066 -5.020

REF 70000 63000 0.00672094711 -5.003

C-73
Table C-2-1. BAGGING DATA USED TO DEVELOP PEGGED EMISSION RATES

(CONTINUED)

Natural

Initial Final Log of

Screening Screening Measured Emission

Plant Value Value Emission Rate

Type (ppmv) (ppmv) Rate(kg/hr) (kg/hr)

ONOFF 80000 100000 0.00687607729 -4.980

ONOFF 100000 100000 0.00845640933 -4.773

ONOFF 80000 100000 0.00850403701 -4.767

REF 100000 100000 0.00879071033 -4.734

REF 90000 90000 0.00915767033 -4.693

ONOFF 100000 100000 0.00999909281 -4.605

REF 100000 100000 0.01077791890 -4.530

ONOFF 100000 100000 0.01084051529 -4.524

ONOFF 10000 10000 0.01150231334 -4.465

ONOFF 100000 100000 0.01338700898 -4.313

REF 50000 100000 0.01343826544 -4.310

REF 16000 80000 0.01372947473 -4.288

ONOFF 100000 100000 0.01451056881 -4.233

ONOFF 50000 50000 0.01612628141 -4.127

ONOFF 30000 100000 0.01659711512 -4.099

ONOFF 100000 100000 0.01664837159 -4.095

REF 58000 58000 0.01690556110 -4.080

REF 120000 120000 0.01879887508 -3.974

ONOFF 100000 100000 0.01883380205 -3.972

ONOFF 100000 100000 0.02038374308 -3.893

ONOFF 100000 100000 0.02074389912 -3.876

ONOFF 100000 100000 0.02144924249 -3.842

ONOFF 100000 100000 0.02216048263 -3.809

ONOFF 100000 100000 0.02497323778 -3.690

REF 71400 71400 0.02521500499 -3.680

ONOFF 100000 100000 0.02522135535 -3.680

ONOFF 100000 100000 0.02819150866 -3.569

ONOFF 100000 100000 0.03083597932 -3.479

ONOFF 100000 100000 0.03347137803 -3.397

ONOFF 100000 100000 0.03378118480 -3.388

ONOFF 100000 100000 0.03389685204 -3.384

ONOFF 100000 100000 0.03527669418 -3.345

ONOFF 100000 100000 0.03595482174 -3.325

ONOFF 100000 100000 0.03649097342 -3.311

ONOFF 100000 100000 0.03771114941 -3.278

ONOFF 100000 100000 0.03832713417 -3.262

ONOFF 5000 10000 0.04127914361 -3.187

ONOFF 100000 100000 0.04416220630 -3.120

ONOFF 100000 100000 0.04438764402 -3.115

ONOFF 60000 70000 0.04505624603 -3.100

ONOFF 100000 100000 0.04937176812 -3.008

ONOFF 10000 10000 0.05139208927 -2.968

ONOFF 100000 100000 0.05296924612 -2.938

ONOFF 100000 100000 0.05525764311 -2.896

ONOFF 100000 100000 0.06018007802 -2.810

MT 90000 300000 0.06055973873 -2.804

ONOFF 10000 10000 0.06589585412 -2.720

ONOFF 10000 10000 0.06919123651 -2.671

ONOFF 10000 100000 0.06986891046 -2.661

C-74
Table C-2-1. BAGGING DATA USED TO DEVELOP PEGGED EMISSION RATES

(CONTINUED)

Natural

Initial Final Log of

Screening Screening Measured Emission

Plant Value Value Emission Rate

Type (ppmv) (ppmv) Rate(kg/hr) (kg/hr)

ONOFF 100000 100000 0.07176086365 -2.634

REF 100000 100000 0.07735190057 -2.559

ONOFF 100000 100000 0.08639118207 -2.449

ONOFF 10000 10000 0.08908826998 -2.418

ONOFF 100000 100000 0.09582463939 -2.345

ONOFF 100000 100000 0.15789757779 -1.846

ONOFF 100000 100000 0.18449242493 -1.690

ONOFF 100000 100000 0.18958677311 -1.663

ONOFF 100000 100000 0.19712873084 -1.624

ONOFF 100000 100000 0.21433094439 -1.540

ONOFF 100000 100000 0.22602739726 -1.487

ONOFF 100000 100000 0.27724439808 -1.283

ONOFF 10000 10000 0.28369636215 -1.260

ONOFF 100000 100000 0.28827360973 -1.244

ONOFF 100000 100000 0.38205751610 -0.962

ONOFF 100000 100000 0.44049986392 -0.820

ONOFF 100000 100000 0.81931597569 -0.199

ONOFF 100000 100000 1.13625011340 0.128

N = 133

----------- Equipment Type=VALVE SERVICE=HL -----------

REF 10000 16000 0.00043354350 -7.744

REF 11000 12000 0.00223700445 -6.103

N=2

----------- Equipment Type=VALVE SERVICE=LL -----------

ONOFF 10000 10000 0.00002404064 -10.636

ONOFF 10000 10000 0.00002449424 -10.617

ONOFF 100000 100000 0.00003447337 -10.275

REF 80000 32000 0.00009142702 -9.300

ONOFF 15000 20000 0.00010342012 -9.177

REF 16000 32000 0.00013744443 -8.892

ONOFF 10000 4000 0.00018279960 -8.607

MT 19800 22000 0.00023388370 -8.361

REF 13500 10800 0.00025930781 -8.257

REF 42000 28000 0.00035377846 -7.947

MT 17600 26400 0.00043848771 -7.732

REF 49500 36000 0.00044372675 -7.720

REF 70000 35000 0.00045913091 -7.686

REF 18000 22500 0.00046035562 -7.684

ONOFF 10000 10000 0.00050122471 -7.598

ONOFF 20000 20000 0.00052617255 -7.550

ONOFF 10000 10000 0.00056563549 -7.478

REF 2000 10000 0.00056713236 -7.475

C-75
Table C-2-1. BAGGING DATA USED TO DEVELOP PEGGED EMISSION RATES

(CONTINUED)

Natural

Initial Final Log of

Screening Screening Measured Emission

Plant Value Value Emission Rate

Type (ppmv) (ppmv) Rate(kg/hr) (kg/hr)

REF 10000 24000 0.00059525538 -7.427

REF 24000 24000 0.00060782001 -7.406

ONOFF 100000 60000 0.00065091173 -7.337

ONOFF 30000 4000 0.00068220992 -7.290

ONOFF 20000 20000 0.00070443618 -7.258

ONOFF 10000 10000 0.00070488978 -7.257

ONOFF 70000 40000 0.00075932142 -7.183

REF 50000 30000 0.00095572893 -6.953

ONOFF 60000 50000 0.00102558287 -6.882

REF 11000 11000 0.00113353896 -6.782

REF 80000 80000 0.00134786356 -6.609

ONOFF 80000 100000 0.00135625510 -6.603

MT 10000 11984 0.00142805951 -6.551

REF 25000 18000 0.00153742175 -6.478

ONOFF 10000 10000 0.00168647374 -6.385

ONOFF 350 10000 0.00185929420 -6.288

ONOFF 20000 15000 0.00211829810 -6.157

ONOFF 40000 70000 0.00223351175 -6.104

ONOFF 10000 10000 0.00225936678 -6.093

ONOFF 10000 10000 0.00226753152 -6.089

ONOFF 100000 100000 0.00230064411 -6.075

ONOFF 50000 35000 0.00247028939 -6.003

REF 58000 58000 0.00307012610 -5.786

ONOFF 10000 9000 0.00325773383 -5.727

REF 70000 70000 0.00345051256 -5.669

ONOFF 9000 10000 0.00417490701 -5.479

ONOFF 90000 100000 0.00426290484 -5.458

ONOFF 100000 100000 0.00436587136 -5.434

ONOFF 10000 10000 0.00454277420 -5.394

ONOFF 100000 100000 0.00488886873 -5.321

REF 5000 40000 0.00500408237 -5.298

REF 70000 70000 0.00507983308 -5.282

ONOFF 100000 100000 0.00518234600 -5.262

ONOFF 100000 100000 0.00592896671 -5.128

ONOFF 10000 10000 0.00596117209 -5.122

REF 24500 27300 0.00601378935 -5.114

ONOFF 100000 100000 0.00647010796 -5.041

REF 131400 146000 0.00666334029 -5.011

REF 30000 70000 0.00844506940 -4.774

REF 55000 100000 0.00920847319 -4.688

ONOFF 100000 100000 0.01027941577 -4.578

ONOFF 100000 100000 0.01037285675 -4.569

ONOFF 10000 10000 0.01041458768 -4.565

ONOFF 10000 10000 0.01133221446 -4.480

ONOFF 10000 10000 0.01256146240 -4.377

REF 67000 67000 0.01319241586 -4.328

REF 140000 140000 0.01378798875 -4.284

ONOFF 10000 10000 0.01564138619 -4.158

REF 17000 34000 0.01730744806 -4.057

C-76
Table C-2-1. BAGGING DATA USED TO DEVELOP PEGGED EMISSION RATES

(CONTINUED)

Natural

Initial Final Log of

Screening Screening Measured Emission

Plant Value Value Emission Rate

Type (ppmv) (ppmv) Rate(kg/hr) (kg/hr)

ONOFF 100000 100000 0.01835979316 -3.998

REF 100000 100000 0.01882427651 -3.973

ONOFF 45000 45000 0.01897986029 -3.964

REF 76000 69850 0.02037603193 -3.893

REF 100000 100000 0.02065272612 -3.880

ONOFF 10000 10000 0.02356890139 -3.748

REF 87500 87500 0.02427696634 -3.718

REF 100000 100000 0.02519096435 -3.681

REF 39000 39000 0.02586999909 -3.655

ONOFF 100000 100000 0.02691508664 -3.615

REF 70000 70000 0.03012791436 -3.502

ONOFF 10000 10000 0.03019504672 -3.500

ONOFF 10000 10000 0.03919486528 -3.239

ONOFF 10000 10000 0.08274879797 -2.492

ONOFF 100000 100000 0.08523224168 -2.462

ONOFF 10000 10000 0.08567948834 -2.457

ONOFF 100000 100000 0.08933548036 -2.415

ONOFF 100000 100000 0.09434591309 -2.361

ONOFF 100000 100000 0.10369500136 -2.266

REF 70000 70000 0.18793885512 -1.672

ONOFF 100000 100000 0.38088768938 -0.965

N = 88

----------- Equipment Type=VENT SERVICE=G -----------

ONOFF 100000 100000 0.00012972875 -8.950

ONOFF 100000 100000 0.00851719133 -4.766

ONOFF 100000 100000 0.00923206024 -4.685

ONOFF 100000 100000 0.02947428105 -3.524

N=4

----------- Equipment Type=VENT SERVICE=LL -----------

ONOFF 100000 100000 0.00005443164 -9.819

ONOFF 100000 100000 0.00027714778 -8.191

ONOFF 10000 10000 0.00117844507 -6.744

ONOFF 10000 10000 0.00200762043 -6.211

N=4

C-77
TABLE C-2-2. PEGGED VOC MASS EMISSION RATES AND 95 PERCENT CONFIDENCE 

READINGS PEGGED AT 10,000 PPMV DEVELOPED FROM THE COMBINED 1993 REFINE

TERMINAL, AND OIL AND GAS PRODUCTION OPERATIONS DATA

Equipment

Type/Service Sample Size

Normal Statistica

(Probability of a

Larger Normal

Statistic)

Mean

Natural

Log Mass

Emission

Rate

Scale Bias

Correction

Factor

Lower

95 Percent

Confidence

Bound for

Pegged

Emission

Rate (kg/hr)

Pe

Em

Rate 

Mass

Emission

Rate

ln Mass

Emission

Rate

Connector/All 74 0.5569

(0.0000)

0.9631

(0.0945) -6.067 12.24 0.01668 0.0

Flange/All 24 0.6790

(0.0000)

0.9424

(0.1899) -5.312 17.25 0.02877 0.0

Open-EndedLine/All

87 0.2597

(0.0000)

0.9819

(0.6620) -6.374 17.78 0.01797 0.0

Pump/All 12 0.3985

(0.0000)

0.8640

(0.0519) -4.869 9.63 0.01609 0.0

Valve/All 223 0.3740

(0.000)

0.9774

(0.1524) -5.301 12.84 0.04741 0.0

Other

b/All 25 0.4359

(0.0000)

0.9506

(0.2710) -5.219 13.46 0.02665 0.0

aThe Normal Statistic is generated by default from SAS--by default the S

statistic is calculated for sample sizes less than 2,000. Probabilitie0.05 indicate a normal distribution.

bThe "other" equipment type was developed from instruments, loading arms

relief valves, stuffing boxes, vents, compressors, and dump lever arms. equipment type should be applied to any equipment other than connectorsopen-ended lines, pumps, or valves.

C-78
TABLE C-2-3. PEGGED VOC MASS EMISSION RATES AND 95 PERCENT CONFIDENCE 

READINGS PEGGED AT 100,000 PPMV DEVELOPED FROM THE COMBINED 1993 REFINE

TERMINAL, AND OIL AND GAS PRODUCTION OPERATIONS DATA

Equipment

Type/Service

Sample

Size

Normal Statistica

(Probability of a Larger

Normal Statistic)

Mean

Natural

Log Mass

Emission

Rate

Scale Bias

Correction

Factor

Lower

95 Percent

Confidence

Bound for

Pegged

Emission Rate

(kg/hr)

Peg

Emis

Rate (

Mass

Emission

Rate

ln Mass

Emission

Rate

Connector/All 33 0.6405

(0.0000)

0.9579

(0.2747) -5.739 9.25 0.01359 0.02

Flange/All 12 0.8101

(0.0106)

0.8653

(0.0539) -3.969 4.47 0.02515 0.08

Open-Ended Line/All 36 0.3759

(0.0000)

0.9444

(0.0918) -4.893 10.55 0.03672 0.07

Pump/All

b - - - - - - 0.16

Valve/All 99 0.4680

(0.0000)

0.9519

(0.0042) -4.388 11.30 0.08984 0.14

Other/Allc 19 0.4759

(0.0000)

0.9140

(0.0900) -4.853 14.61 0.03374 0.11

aThe Normal Statistic is generated by default from SAS--by default the S

statistic is calculated for sample sizes less than 2,000. Probabilitie0.05 indicate a normal distribution.

bOnly 2 data points were available for the pump emission factor; therefo

the pump/overall 10,000 ppmv emission factor was multiplied by the overppmv emission factor to approximate the pump 100,000 ppmv emission fact

cThe "other" equipment type was developed from instruments, loading arms

relief valves, stuffing boxes, vents, compressors, and dump lever arms. equipment type should be applied to any equipment other than connectorsopen-ended lines, pumps, or valves.

C-79
APPENDIX C: ATTACHEMENT 3

This attachment lists the bagging data used to develop the default

zero emission rates for the combined 1993 petroleum industry data in

table C-3-1. Table C-3-2 lists summary statistics for the default zero

emission rates.

C-80
TABLE C-3-1. BAGGING DATA USED TO DEVELOP DEFAULT ZERO EMISSION RATES

Natural

Log of

Measured Emission

Plant Screening Emission Rate

Type Value (ppmv) Rate(kg/hr) (kg/hr)

----------- Equipment Type=CONNECTOR SERVICE=G -----------

REF 0.00 0.00000000476 -19.163

REF 0.00 0.00000000636 -18.873

REF 0.00 0.00000002555 -17.483

REF 0.00 0.00000023605 -15.259

REF 0.00 0.00000038635 -14.767

REF 0.00 0.00000362959 -12.526

N=6

----------- Equipment Type=CONNECTOR SERVICE=LL -----------

REF 0.00 0.00000000501 -19.112

REF 0.00 0.00000000544 -19.030

REF 0.00 0.00000000739 -18.723

REF 0.00 0.00000000763 -18.691

REF 0.00 0.00000000777 -18.673

MT 0.00 0.00000137993 -13.493

MT 0.00 0.00000177942 -13.239

MT 0.00 0.00000258886 -12.864

MT 0.00 0.00000332328 -12.615

REF 0.00 0.00000470743 -12.266

MT 0.00 0.00000863240 -11.660

MT 0.00 0.00001050395 -11.464

N = 12

----------- Equipment Type=FLANGE SERVICE=G -----------

REF 0.00 0.00000000642 -18.863

REF 0.00 0.00000000709 -18.764

REF 0.00 0.00000007912 -16.352

REF 0.00 0.00000080155 -14.037

N=4

----------- Equipment Type=FLANGE SERVICE=LL -----------

REF 0.00 0.00000000958 -18.464

REF 0.00 0.00000019031 -15.475

REF 0.00 0.00000021919 -15.333

REF 0.00 0.00000021930 -15.333

REF 0.00 0.00000047102 -14.568

N=5

----------- Equipment Type=LOADARM SERVICE=LL -----------

MT 0.00 0.00005125646 -9.879

C-81
TABLE C-3-1. BAGGING DATA USED TO DEVELOP DEFAULT ZERO EMISSION RATES

(CONTINUED)

Natural

Log of

Measured Emission

Plant Screening Emission Rate

Type Value (ppmv) Rate(kg/hr) (kg/hr)

N=1

----------- Equipment Type=OEL SERVICE=G -----------

REF 0.00 0.00000000693 -18.788

REF 0.00 0.00000140955 -13.472

MT 0.00 0.00000303602 -12.705

MT 0.00 0.00000334319 -12.609

N=4

----------- Equipment Type=OEL SERVICE=HL -----------

REF 0.00 0.00000000575 -18.975

REF 0.00 0.00000000583 -18.960

REF 0.00 0.00000001096 -18.329

REF 0.00 0.00000009800 -16.138

N=4

----------- Equipment Type=OEL SERVICE=LL -----------

REF 0.00 0.00000000511 -19.093

REF 0.00 0.00000000540 -19.036

REF 0.00 0.00000076594 -14.082

MT 0.00 0.00000288878 -12.755

N=4

----------- Equipment Type=PRV SERVICE=G -----------

REF 0.00 0.00000000710 -18.763

REF 0.00 0.00000000807 -18.635

REF 0.00 0.00000001125 -18.303

N=3

----------- Equipment Type=PUMP SERVICE=HL -----------

REF 0.00 0.00000002008 -17.723

REF 0.00 0.00000002256 -17.607

REF 0.00 0.00000002315 -17.581

REF 0.00 0.00000002586 -17.471

REF 0.00 0.00000089186 -13.930

N=5

C-82
TABLE C-3-1. BAGGING DATA USED TO DEVELOP DEFAULT ZERO EMISSION RATES

(CONTINUED)

Natural

Log of

Measured Emission

Plant Screening Emission Rate

Type Value (ppmv) Rate(kg/hr) (kg/hr)

----------- Equipment Type=PUMP SERVICE=LL -----------

REF 0.00 0.00000002503 -17.503

REF 0.00 0.00000002714 -17.422

REF 0.00 0.00000005485 -16.719

REF 0.00 0.00000006666 -16.524

REF 0.00 0.00000053647 -14.438

REF 0.00 0.00000186896 -13.190

MT 0.00 0.00000480541 -12.246

MT 0.00 0.00000775832 -11.767

MT 0.00 0.00000998821 -11.514

MT 0.00 0.00001319922 -11.235

MT 0.00 0.00001436632 -11.151

MT 0.00 0.00001653679 -11.010

REF 0.00 0.00002058968 -10.791

MT 0.00 0.00006269164 -9.677

N = 14

----------- Equipment Type=VALVE SERVICE=G -----------

REF 0.00 0.00000000775 -18.676

REF 0.00 0.00000000865 -18.565

REF 0.00 0.00000000940 -18.482

REF 0.00 0.00000000990 -18.431

REF 0.00 0.00000001019 -18.402

REF 0.00 0.00000001420 -18.070

REF 0.00 0.00000002762 -17.405

REF 0.00 0.00000003664 -17.122

REF 0.00 0.00000003966 -17.043

REF 0.00 0.00000004455 -16.927

REF 0.00 0.00000020591 -15.396

REF 0.00 0.00000032682 -14.934

REF 0.00 0.00000032845 -14.929

REF 0.00 0.00000061449 -14.302

REF 0.00 0.00000083416 -13.997

MT 0.00 0.00000125837 -13.586

MT 0.00 0.00000196249 -13.141

MT 0.00 0.00000201696 -13.114

MT 0.00 0.00000208210 -13.082

REF 0.00 0.00000218398 -13.034

MT 0.00 0.00000238633 -12.946

MT 0.00 0.00000798694 -11.738

REF 0.00 0.00000893314 -11.626

REF 0.00 0.00001171097 -11.355

REF 0.00 0.00001563050 -11.066

N = 25

C-83
TABLE C-3-1. BAGGING DATA USED TO DEVELOP DEFAULT ZERO EMISSION RATES

(CONTINUED)

Natural

Log of

Measured Emission

Plant Screening Emission Rate

Type Value (ppmv) Rate(kg/hr) (kg/hr)

----------- Equipment Type=VALVE SERVICE=HL -----------

REF 0.00 0.00000000660 -18.836

REF 0.00 0.00000000665 -18.828

REF 0.00 0.00000001034 -18.387

REF 0.00 0.00000001058 -18.364

REF 0.00 0.00000001345 -18.124

REF 0.00 0.00000001638 -17.927

REF 0.00 0.00000004990 -16.813

REF 0.00 0.00000005393 -16.736

REF 0.00 0.00000005530 -16.710

REF 0.00 0.00000240865 -12.936

REF 0.00 0.00001479770 -11.121

REF 0.00 0.00002881475 -10.455

REF 0.00 0.00003605008 -10.231

N = 13

----------- Equipment Type=VALVE SERVICE=LL -----------

REF 0.00 0.00000000467 -19.182

REF 0.00 0.00000000637 -18.871

REF 0.00 0.00000000664 -18.830

REF 0.00 0.00000000691 -18.791

REF 0.00 0.00000000834 -18.602

REF 0.00 0.00000000976 -18.445

REF 0.00 0.00000000997 -18.423

REF 0.00 0.00000001104 -18.322

REF 0.00 0.00000001198 -18.240

REF 0.00 0.00000002004 -17.725

REF 0.00 0.00000002139 -17.660

REF 0.00 0.00000002191 -17.636

REF 0.00 0.00000002793 -17.394

REF 0.00 0.00000005696 -16.681

REF 0.00 0.00000007503 -16.405

REF 0.00 0.00000048449 -14.540

REF 0.00 0.00000053602 -14.439

MT 0.00 0.00000103293 -13.783

MT 0.00 0.00000112977 -13.693

REF 0.00 0.00000192842 -13.159

MT 0.00 0.00000195101 -13.147

MT 0.00 0.00000195727 -13.144

MT 0.00 0.00000220253 -13.026

REF 0.00 0.00000233299 -12.968

REF 0.00 0.00000234795 -12.962

REF 0.00 0.00000312302 -12.677

REF 0.00 0.00000683117 -11.894

C-84
TABLE C-3-1. BAGGING DATA USED TO DEVELOP DEFAULT ZERO EMISSION RATES

(CONTINUED)

Natural

Log of

Measured Emission

Plant Screening Emission Rate

Type Value (ppmv) Rate(kg/hr) (kg/hr)

REF 0.00 0.00000696181 -11.875

REF 0.00 0.00000698812 -11.871

REF 0.00 0.00001664883 -11.003

N = 30

C-85
TABLE C-3-2. DEFAULT ZERO VOC MASS EMISSION RATES AND 95 PERCENT CONFID

DEVELOPED FROM THE COMBINED 1993 REFINERY AND MARKETING TERMINAL 

Equipment

Type/Service

Sample

Size

Normal Statistic

b

(Probability of a

Larger Normal

Statistic)

Mean ln

Mass

Emission

Rate

Scale Bias

Correction

Factor

Lower

95 Percent

Confidence

Bound for

Default Zero

Emission

Rate (kg/hr)

Default 

Emis

Rate (k

Mass

Emission

Rate

ln Mass

Emission

Rate

Connector/All 18 0.7177

(0.0001)

0.8302

(0.0034) -15.550 42.72 1.64E-06 7.54E

Flange/All 9 0.8137

(0.0296)

0.8687

(0.1173) -16.354 3.94 7.39E-08 3.11E

Open-Ended Line/All 12 0.7232

(0.0009)

0.7909

(0.0061) -16.245 22.70 3.19E-07 2.00E

Pump/All 19 0.5942

(0.0000)

0.8532

(0.0065) -14.184 34.97 5.81E-06 2.42E

Valve/All 68 0.5178

(0.0000)

0.8764

(0.0000) -15.415 38.38 3.95E-06 7.75E

Otherc/All

4 0.6297

(0.0000)

0.6691

(0.0045) -16.395 52.16 3.91E-09 3.95E

aNo default zero data were collected from oil and gas production facilitbThe Normal Statistic is generated by default from SAS--by default the S

statistic is calculated for sample sizes less than 2,000. Probabilitie0.05 indicate a normal distribution.

cThe "other" equipment type were developed from instruments, loading arm

relief valves, stuffing boxes, vents, compressors, and dump lever arms. equipment type should be applied to any equipment other than connectorsopen-ended lines, pumps, or valves.

C-86
APPENDIX C: ATTACHMENT 4

Because it would be impractical to list all of the screening

data used to develop emission factors, this attachment summarizes

the 1993 marketing terminal and oil and gas production operations

screening data sets. Figures C-4-1 through C-4-4 are plots of

the distribution of screening values for marketing terminals and

figures C-5-5 through C-5-10 are plots of the distribution of

screening valves for oil and gas production operations.

C-87
Figure C-4-1. Distribution of Connector Screening Values for

Marketing Terminals

C-88
Figure C-4-2. Distribution of Other Screening Values for

Marketing Terminals

C-89
Figure C-4-3. Distribution of Pump Screening Values for

Marketing Terminals

C-90
Figure C-4-4. Distribution of Valve Screening Values for

Marketing Terminals

C-91
Figure C-4-5. Distribution of Connector Screening Values for Oil

and Gas Operations

C-92
Figure C-4-6. Distribution of Flange Screening Values for Oil

and Gas Operations

C-93
Figure C-4-7. Distribution of Open-Ended Line Screening Values

for Oil and Gas Operations

C-94
Figure C-4-8. Distribution of Pump Screening Values for Oil and

Gas Operations

C-95
Figure C-4-9. Distribution of Valve Screening Values for Oil and

Gas Operations

C-96
Figure C-4-10. Distribution of Other Screening Values for Oil and

Gas Operations

C-97
APPENDIX D: RESPONSE FACTORS
APPENDIX D

RESPONSE FACTORS

The response factors presented in table D-1 were taken from

two separate sources. The response factors at an actual

concentration of 10,000 ppmv are from the EPA document entitled,

"Response Factors of VOC Analyzers Calibrated with Methane for

Selected Organic Chemicals," EPA-600/2-81-002 (September 1980).

The document presents results of analytical tests performed to

determine the response factors at 10,000 ppmv of two portable

monitoring instruments--the Foxboro OVA-108 and the Bacharach

TLV-108. Both instruments were calibrated with methane.

The response factors at a concentration of 500 ppmv are from

the document entitled "Method 21 Evaluation for the HON,

"90-ME-07)" (March 1991) prepared for the Emission Measurement

Branch of the U.S. Environmental Protection Agency. This

document presents the results of analytical tests performed to

determine the response factors at an actual concentration of

500 ppmv of several emission monitors including the Foxboro

OVA-108, two of Foxboro OVA-128 units, the Heath Detecto-PAK III,

and the HNU Systems HW-101. The two Foxboro OVA-128 instrument

response factors are presented in the table to indicate the

variability of individual instruments. To determine the response

factor for the OVA-128, the average of the two instrument

response factors should be used. All of the instruments except

the HNU HW-101 were calibrated with methane. The HNU HW-101 was

calibrated with benzene.

A dashed line in table D-1 indicates that the study did not

test that particular chemical. If the emission monitor did not

respond to a chemical, N/R was recorded to indicate no response.

Operators of portable leak detection devices should be

thoroughly familiar with their instrumentation. Even under the

best of circumstances, no two analyzers will perform exactly the

same and the effect of changes in instrument parameters upon

accuracy can be significant. Other external quality controls,

such as a checklist for periodically noting battery condition,

D-1
fuel pressure, post-survey calibration checks, etc., will support

the validity of the data. An audit program testing both the

operator and the analyzer should be a requirement whenever a

situation warranting an exacting determination of a fugitive

emission is encountered.

In general, the response factors follow the pattern which

would be predicted for increasing flame ionization detector

response with increasing hydrocarbon character for the molecule.

The sequence of compounds methyl chloride, methylene chloride,

chloroform, and carbon tetrachloride exhibits progressively

decreasing response on the OVA detectors (response factors

ranging from 2 to 12) as the substitution on the methyl carbon

atom increases (i.e., decreasing hydrocarbon character for the

molecule). In general, increasing electronegativity of the

substituent decreases the system response: methyl chloride,

response factor approximately 2; methyl bromide, response factor

approximately 5; iodomethane, response factor approximately 8.

Carbon tetrachloride exhibits a response factor of 12 or more,

but tetrachloroethylene has a response factor of 2 or less. The

lack of carbon-hydrogen bonds in tetrachloroethylene is

apparently compensated by the presence of a site of unsaturation

in the molecule (chlorobenzene, response factor 0.60 vs.

trichlorobenzene, response factor of 12 or greater). The

difficulty of obtaining a reproducible and useful response factor

for compounds of insufficient volatility such as nitrobenzene,

m-cresol, and oxygenated compounds such as acrylic acid

demonstrates that there is a point dictated by vapor pressure or

possibly boiling point where an accurate measurement cannot be

made using the portable field analyzers. With compounds which

are not very volatile, the portable field analyzers can be

usedonly qualitatively, at best; if a large amount of the

compound is present in the air, the compound will be observed but

not with a proportionate quantitative response.

D-2
D-3

TABLE D-1. RESPONSE FACTORS AT ACTUAL CONCENTRATIONS OF 10,000 PPMV AN

Actual Concentration:

10,000 ppmV Actual Concentrati

CAS No.# Compound Name

Volatility

Class

Foxboro

OVA - 108a

Bacharach

TLVa

Foxboro

OVA - 108a

Foxboro

OVA - 128a

Foxboro

OVA - 12

75-07-0 Acetaldehyde LL -- -- 8.41 9.96 7.95 

64-19-7 Acetic Acid LL 1.83 5.70 -- -- -- 108-24-7 Acetic anhydride LL 1.36 2.89 -- -- -- 67-64-1 Acetone LL 0.79 1.22 -- -- -- 75-86-5 Acetone cyanohydrin HL 3.42 7.84 -- -- -- 75-05-08 Acetonitrile LL 0.94 1.17 1.20 1.24 1.27 

98-86-2 Acetophenone HL 10.98 54.86 2.71 2.62 2.43 

75-36-5 Acetyl chloride LL 1.99 2.59 -- -- -- 74-86-2 Acetylene G 0.37 11.95 -- -- -- 107-02-8 Acrolein LL -- -- 6.25 6.69 5.64 79-10-7 Acrylic acid LL 4.65 36.95 10.51c 10.81c 9.63c 

107-13-1 Acrylonitrile LL 0.96 2.70 1.55 1.58 1.56 

Allene G 0.55 5.78 -- -- -- 

107-18-6 Allyl alcohol LL 0.94 -- -- -- 107-5-1 Allyl chloride LL -- -- 2.77 2.73 2.51 71-41-0c Amyl alcohol, N- HL 0.69 1.78 -- -- -- 

Amylene LL 0.31 1.03 -- -- -- 

62-53-3 Aniline HL -- -- 14.44c 20.45c 22.68c 

100-66-3 Anisole LL 0.92 2.69 -- -- -- 

100-52-7 Benzaldehyde HL 2.36 6.30 -- -- -- 
TABLE D-1. RESPONSE FACTORS AT ACTUAL CONCENTRATIONS OF 10,000 PPMV AND 50

D-4

Actual Concentration:

10,000 ppmV Actual Concentrati

CAS No.# Compound Name

Volatility

Class

Foxboro

OVA - 108a

Bacharach

TLVa

Foxboro

OVA - 108a

Foxboro

OVA - 128a

Foxboro

OVA - 12

71-43-2 Benzene LL 0.21 1.07 0.56 0.54 0.50 

100-47-0 Benzonitrile HL 2.24 9.13 -- -- -- 98-88-4 Benzoyl Chloride HL 6.40 6.60 -- -- -- 100-44-7 Benzyl Chloride HL 4.20 4.87 1.43 1.42 1.21 10-86-0 Bromobenzene LL 0.36 1.16 -- -- -- 75-25-2 Bromoform LL -- -- 5.90 6.71 5.68 106-99-0 Butadiene, 1,3- G 0.37 6.00 2.41 2.69 2.37 106-97-8 Butane, N- G 0.38 0.68 -- -- -- 71-36-3 Butanol, N- LL 1.43 2.80 -- -- -- 78-92-2 Butanol, Sec- LL 0.70 1.26 -- -- -- 75-65-0 Butanol, Tert- S 0.44 2.19 -- -- -- 106-98-9 Butene, 1- G 0.51 2.97 -- -- -- 111-76-2 Butoxyethanol, 2-c -- -- 19.37c 26.11c 24.69c 

123-86-4 Butyl acetate LL 0.60 1.30 -- -- -- 

141-32-2 Butyl acrylate, N- LL 0.64 1.98 -- -- -- 142-96-1 Butyl ether, N- LL 2.70 2.66 -- -- -- 

Butyl ether, Sec- LL 0.26 1.13 -- -- -- 

109-73-9 Butylamine, N- LL 0.63 1.91 -- -- -- 13952-84-6 Butylamine, Sec- LL 0.67 1.50 -- -- -- 75-64-9 Butylamine, Tert- LL 0.58 1.80 -- -- -- 98-06-6 Butylbenzene, Tert- HL 1.27 6.42 -- -- -- 
TABLE D-1. RESPONSE FACTORS AT ACTUAL CONCENTRATIONS OF 10,000 PPMV AND 50

D-5

Actual Concentration:

10,000 ppmV Actual Concentrati

CAS No.# Compound Name

Volatility

Class

Foxboro

OVA - 108a

Bacharach

TLVa

Foxboro

OVA - 108a

Foxboro

OVA - 128a

Foxboro

OVA - 12

123-72-8 Butyraldehyde, N- LL 1.39 1.89 -- -- -- 

107-92-6 Butyric acid HL 0.74 4.58 -- -- -- 109-74-0 Butyronitrile LL 0.46 1.33 -- -- -- 75-1-50 Carbon disulfide LL -- 2.96 33.87 53.06 N/R 56-23-5 Carbon tetrachloride LL -- -- 12.07 15.99 13.72 

463-58-1 Carbonyl Sulfide G -- -- 103.95 N/R N/R 107-20-0 Chloroacetaldehyde LL 13.40 5.07 -- -- -- 

79-04-9 Chloroacetyl chloride LL -- -- 1.86 1.93 1.66 108-90-7 Chlorobenzene LL 0.36 0.88 0.62 0.60 0.54 75-00-3 Chloroethane G 0.67 2.16 -- -- -- 67-66-3 Chloroform L 4.48 8.77 2.06 2.38 1.91 

Chloromethyl methylether

-- -- 7.77 9.76 7.52 

25167-80-0 Chlorophenol, 0- HL 3.33 5.87 -- -- -- 

50% Chloroprene/xylene -- -- 1.46 1.47 1.27 Chloropropene, 1- LL 0.59 0.86 -- -- -- Chloropropene, 3- LL 0.75 1.24 -- -- -- 

108-41-8 Chlorotoluene, M- LL 0.43 0.92 -- -- -- 95-49-9 Chlorotoluene, O- LL 0.45 1.05 -- -- -- 106-43-4 Chlorotoluene, P- LL 0.52 1.15 -- -- -- 95-48-7 Cresol, O- S 0.95 3.98 -- -- -- 
TABLE D-1. RESPONSE FACTORS AT ACTUAL CONCENTRATIONS OF 10,000 PPMV AND 50

D-6

Actual Concentration:

10,000 ppmV Actual Concentrati

CAS No.# Compound Name

Volatility

Class

Foxboro

OVA - 108a

Bacharach

TLVa

Foxboro

OVA - 108a

Foxboro

OVA - 128a

Foxboro

OVA - 12

108-39-4 Cresol, M- LL -- -- 75.60c 115.20c N/R 

106-44-5 Cresol, P- S -- -- N/R N/R N/R 

4170-30-0 Crotonaldehyde LL 1.32 8.54 -- -- -- 

98-82-8 Cumene LL 1.92 12.49 2.05 1.82 1.55 110-82-7 Cyclohexane LL 0.36 0.72 -- -- -- 108-93-0 Cyclohexanol HL 0.82 4.92 -- -- -- 108-94-1 Cyclohexanone LL 1.50 3.99 -- -- -- 110-83-8 Cyclohexene LL 0.40 1.84 -- -- -- 108-91-8 Cyclohexylamine LL 0.47 1.38 -- -- -- 124-18-5 Decane HL 0.00 0.20 -- -- -- 123-42-2 Diacetone alcohol HL 1.53 0.98 -- -- -- 431-03-8 Diacetyl LL 1.61 2.81 -- -- -- 

Dichloro-1-propene,2,3-

LL 61.51 34.34 -- -- -- 

541-73-1 Dichlorobenzene, M- HL 0.66 1.89 -- -- -- 95-50-1 Dichlorobenzene, O- HL 0.70 1.22 -- -- -- 75-34-3 Dichloroethane, 1,1- LL 0.77 1.80 -- -- -- 107-06-2 Dichloroethane, 1,2- LL 0.95 2.08 -- -- -- 540-59-0 Dichloroethylene, 2- LL 1.31 1.93 -- -- -- 540-59-0 Dichloroethylene,

TRANS, 1,2

LL 1.13 1.86 -- -- -- 

111-44-4 Dichloroethyl etherc -- -- 22.12c 25.10c 24.48c 
TABLE D-1. RESPONSE FACTORS AT ACTUAL CONCENTRATIONS OF 10,000 PPMV AND 50

D-7

Actual Concentration:

10,000 ppmV Actual Concentrati

CAS No.# Compound Name

Volatility

Class

Foxboro

OVA - 108a

Bacharach

TLVa

Foxboro

OVA - 108a

Foxboro

OVA - 128a

Foxboro

OVA - 12

Dichloromethane LL 2.26 3.63 -- -- -- 

Dichloropropane, 1,2- LL 1.03 1.80 -- -- -- 

542-75-6 Dichloropropene, 1,3- -- -- 2.03 2.08 1.93 25167-70-8 Diisobutylene LL 0.24 1.39 -- -- -- 

Dimethoxy ethane, 1,2- LL 1.28 1.43 -- -- -- 

68-12-2 Dimethylformamide, N,N- LL 3.89 2.95 6.42 6.38 7.20 57-14-7 Dimethylhydrazine, 1,1- LL 1.04 2.74 2.68 2.84 3.00 67-68-5 Dimethylsulfoxide HL 0.00 4.88 -- -- -- 123-91-1 Dioxane, 1,4- LL 1.58 1.23 3.74 4.27 3.60 106-89-8 Epichlorohydrin LL 1.72 2.02 2.30 2.41 2.07 106-88-7 Epoxybutane, 1,2- -- -- 2.67 2.54 2.16 74-84-0 Ethane G 0.57 0.73 -- -- -- 64-17-5 Ethanol LL 2.04 -- -- -- -- 110-80-5 Ethoxy ethanol, 2- LL 1.68 1.61 3.55 4.09 3.50 141078-6 Ethyl acetate LL 0.84 3.13 -- -- -- 141-97-9 Ethyl acetoacetate HL 3.02 3.13 -- -- -- 140-88-5 Ethyl acrylate LL 0.72 -- 2.49 2.64 2.18 75-00-3 Ethyl chloride G -- -- 1.68 1.84 1.65 105-39-5 Ethyl chloroacetate LL 1.97 1.47 -- -- -- 60-29-7 Ethyl Ether LL 0.97 1.11 -- -- -- 100-41-4 Ethylbenzene LL 0.70 3.14 0.77 0.76 0.66 
TABLE D-1. RESPONSE FACTORS AT ACTUAL CONCENTRATIONS OF 10,000 PPMV AND 50

D-8

Actual Concentration:

10,000 ppmV Actual Concentrati

CAS No.# Compound Name

Volatility

Class

Foxboro

OVA - 108a

Bacharach

TLVa

Foxboro

OVA - 108a

Foxboro

OVA - 128a

Foxboro

OVA - 12

74-85-1 Ethylene G 0.52 4.49 -- -- -- 

106-93-4 Ethylene dibromide -- -- 2.03 2.22 2.03 107-06-2 Ethylene dichloride LL -- -- 1.37 1.59 1.41 107-21-1 Ethylene glycolc -- -- 24.81 39.39 N/R 75-21-8 Ethylene oxide G 2.72 2.43 2.40 2.77 2.40 107-15-3 Ethylenediamine LL 1.78 2.46 -- -- -- 64-18-6 Formic Acid LL 34.87 33.21 -- -- -- 

Formalin (37%formaldehyde/H2O)

-- -- 18.83 31.39 27.66 

556-52-5 Glycidol LL 8.42 5.23 -- -- -- 

142-82-5 Heptane LL 0.30 0.75 -- -- -- 87-68-3 Hexachlorobutadienec -- -- 16.28c 22.99c 18.06c 

100-54-3 Hexane, N- LL 0.31 0.72 1.42 1.49 1.33 

592-41-6 Hexene, 1- LL 0.39 2.92 -- -- -- 

Hydroxyacetone LL 8.70 9.34 -- -- -- 

74-88-4 Iodomethane -- -- 8.06 8.76 7.35 75-28-5 Isobutane G 0.30 0.61 -- -- -- 115-11-7 Isobutylene G 2.42 6.33 -- -- -- 540-84-1 Isooctane LL -- -- 1.05 1.05 0.89 78-79-5 Isoprene LL 0.38 -- -- -- -- 78-59-1 Isophoronec -- -- 28.80 40.71 N/R 
TABLE D-1. RESPONSE FACTORS AT ACTUAL CONCENTRATIONS OF 10,000 PPMV AND 50

D-9

Actual Concentration:

10,000 ppmV Actual Concentrati

CAS No.# Compound Name

Volatility

Class

Foxboro

OVA - 108a

Bacharach

TLVa

Foxboro

OVA - 108a

Foxboro

OVA - 128a

Foxboro

OVA - 12

67-63-0 Isopropanol LL 0.90 1.35 -- -- -- 

108-21-4 Isopropyl acetate LL 0.68 1.25 -- -- -- 75-29-6 Isopropyl chloride LL 0.62 0.99 -- -- -- 590-86-3 Isovaleraldehyde LL 0.55 2.04 -- -- -- 141-79-7 Mesityl oxide LL 1.12 3.12 -- -- -- 78-85-3 Methacrolein LL 1.27 3.10 -- -- -- 79-41-4 Methacrylic acid HL 0.71 6.61 -- -- -- 67-56-1 Methanol LL 5.69 1.88 13.24 17.34 N/R 111-90-0 Methoxy-ethanol, 2- LL 2.70 2.19 9.61c 9.87c N/R 79-20-9 Methyl acetate LL 1.80 1.76 -- -- -- 74-99-7 Methyl acetylene G 0.53 3.92 -- -- -- 74-83-9 Methyl bromide G -- -- 3.71 3.83 3.46 74-87-3 Methyl chloride G 1.75 2.45 1.97 2.38 1.97 78-93-3 Methyl ethyl ketone LL 0.57 1.12 1.78 1.84 1.59 107-31-3 Methyl formate LL 3.47 1.93 -- -- -- 60-34-4 Methyl hydrazine LL -- -- 5.47 5.50 5.74 108-10-1 Methyl isobutyl ketone LL -- -- 1.65 1.69 1.40 80-62-6 Methyl methacrylate LL 0.99 2.36 2.02 2.16 1.81 

Methyl tert-butylketone

-- -- 1.23 1.25 1.03 

108-11-2 Methyl-2-pentanol, 4- LL 1.70 1.94 -- -- -- 
TABLE D-1. RESPONSE FACTORS AT ACTUAL CONCENTRATIONS OF 10,000 PPMV AND 50

D-10

Actual Concentration:

10,000 ppmV Actual Concentrati

CAS No.# Compound Name

Volatility

Class

Foxboro

OVA - 108a

Bacharach

TLVa

Foxboro

OVA - 108a

Foxboro

OVA - 128a

Foxboro

OVA - 12

Methyl-2-pentanone, 4- LL 0.49 1.54 -- -- -- 

Methyl-3-butyn-2-OL, 2- LL 0.51 -- -- -- -- 

109-87-5 Methylal LL 1.46 1.41 -- -- -- 100-61-8 Methylaniline, N- HL 4.13 5.25 -- -- -- 108-87-2 Methylcyclohexane LL 0.38 0.85 -- -- -- 

Methylcyclohexene, 1- LL 0.33 2.22 -- -- -- 

75-09-2 Methylene chloride LL 2.26 3.63 1.67 1.72 1.41 77-75-8 Methylpentynol LL 1.17 2.82 -- -- -- 98-83-9 Methylstyrene, A- LL 10.24 31.46 -- -- -- 110-91-8 Morpholine LL 0.92 1.93 -- -- -- 98-95-3 Nitrobenzene HL 29.77 40.61 16.41c 16.52c N/R 79-24-3 Nitroethane LL 1.40 2.54 -- -- -- 75-52-5 Nitromethane LL 3.32 5.25 -- -- -- 24332-01-4 Nitropropane, 2- LL 1.06 1.77 1.86 1.91 1.60 111-84-2 Nonane-N LL 1.62 5.54 -- -- -- 111-65-9 Octane LL 1.04 2.06 -- -- -- 

Phenol (90% carboxylicacid)

LL -- -- 16.38 44.89 47.01 

109-66-0 Pentane LL 0.42 0.62 -- -- -- 

109-06-8 Picoline, 2- LL 0.34 1.17 -- -- -- 74-98-6 Propane G 0.88 0.63 -- -- -- 
TABLE D-1. RESPONSE FACTORS AT ACTUAL CONCENTRATIONS OF 10,000 PPMV AND 50

D-11

Actual Concentration:

10,000 ppmV Actual Concentrati

CAS No.# Compound Name

Volatility

Class

Foxboro

OVA - 108a

Bacharach

TLVa

Foxboro

OVA - 108a

Foxboro

OVA - 128a

Foxboro

OVA - 12

123-38-6 Propionaldehyde LL 1.19 1.65 4.01 4.27 3.95 

79-09-4 Propionic acid LL 1.34 3.51 -- -- -- 71-23-8 Propyl alcohol LL 0.91 1.55 -- -- -- 103-65-1 Propylbenzene, N- LL 0.44 5.97 -- -- -- 115-07-1 Propylene G 0.79 2.80 -- -- -- 78-87-5 Propylene dichloride LL -- -- 1.49 1.48 1.26 75-56-0 Propylene oxide LL 0.80 1.15 2.02 2.14 1.78 75-55-8 Propyleneimine, 1,2- -- -- 1.75 1.52 1.53 110-86-1 Pyridine LL 0.41 1.17 -- -- -- 100-42-5 Styrene LL 4.16 36.83 1.10 1.08 0.93 96-09-3 Styrene Oxide L -- -- 2.61 2.49 2.06 79-34-5C Tetrachloroethane,

1,1,1,2-

LL 3.00 6.52 -- -- -- 

Tetrachloroethane,1,1,2,2-

LL 6.06 14.14 1.64 1.69 1.66 

127-18-4 Tetrachloroethylene LL 3.16 11.46 1.77 2.09 1.72 108-88-3 Toluene LL 0.33 2.32 0.87 0.87 0.76 120-82-1 Trichlorobenzene, 1,2,4 1.35 0.39 12.55 16.71 N/R 71-55-6 Trichloroethane, 1,1,1- LL 0.79 2.41 1.09 1.16 1.03 79-00-5 Trichloroethane, 1,1,2- LL 1.26 3.68 1.19 1.27 1.11 79-01-6 Trichloroethylene LL 0.94 3.35 2.26 2.60 2.14 96-18-4 Trichloropropane,

1,2,3-

LL 0.95 2.23 -- -- -- 
TABLE D-1. RESPONSE FACTORS AT ACTUAL CONCENTRATIONS OF 10,000 PPMV AND 50

D-12

Actual Concentration:

10,000 ppmV Actual Concentrati

CAS No.# Compound Name

Volatility

Class

Foxboro

OVA - 108a

Bacharach

TLVa

Foxboro

OVA - 108a

Foxboro

OVA - 128a

Foxboro

OVA - 12

121-44-8 Triethylamine LL 0.46 1.41 0.47 0.49 0.48 

108-05-4 Vinyl acetate LL 1.31 3.99 3.63 3.36 2.80 593-60-2 Vinyl bromide G -- -- 2.14 2.41 2.33 75-01-4 Vinyl chloride G 0.65 1.10 2.03 2.11 2.11 

Vinyl propionate LL 0.94 0.70 -- -- -- 

75-35-4 Vinylidene chloride LL 1.15 2.38 2.73 2.97 2.61 106-42-3 Xylene, P- LL 2.27 5.35 0.89 0.88 0.74 108-38-3 Xylene, M- LL 0.30 3.56 0.89 0.89 0.75 

95-47-6 Xylene, O- LL 0.36 1.40 0.95 0.95 0.80 

N/R = No responsea = Calibrated with methane in air. b = Calibrated with benzene in air. c = Volatility problem with compound.
APPENDIX E

SELECTION OF SAMPLE SIZE FOR SCREENING CONNECTORS
APPENDIX E

SELECTION OF SAMPLE SIZE FOR SCREENING CONNECTORS

In estimating emissions for a given process unit, all

equipment components must be surveyed for each class of

components. The one exception to this "total component

screening" criterion is the category of connectors. Note

however, that if the process unit is subject to a standard which

requires the screening of connectors, then all connectors must be

screened. In typical process units, connectors represent the

largest count of individual equipment components, making it

costly to screen all components. The purpose of this appendix is

to present a methodology for determining how many connectors must

be screened to constitute a large enough sample size to identify

the actual screening value distribution of connectors in the

entire process unit. Please note that the sampling is to be a

random sampling throughout the process unit.

The basis for selecting the sample population to be screened

is the probability that at least one "leaking" connector will be

in the screened population. The "leaker" is used as a

representation of the complete distribution of screening values

for the entire class of sources. The following binomial

distribution was developed to approximate the number of

connectors that must be screened to ensure that the entire

distribution of screening values for these components is

represented in the sample:

n ≥ N × {1 - (1 -p)1/D] (E-1)

where:

N = Number of connectors;

D = (fraction of leaking connectors) × N; and

p ≥ 0.95.

E-1
Refer to figure E-1, which shows the fraction of leaking

connectors at several leak definitions based on currently

available data. Since the fraction of leaking connectors will

most likely not be known prior to screening, the leaking fraction

at the intersection of the SOCMI average emission factor line and

applicable leak definition line on figure F-1 can be used to

estimate what the fraction of leaking connectors will be.

Entering this value into equation E-1 for at least a 95 percent

confidence interval (p = 0.95) will give the minimum number of

connectors that need to be screened. A larger sample size will

be required for units exhibiting a lower fraction of leaking

connectors.

After ’n’ connectors have been screened, an actual leak

frequency should be calculated as follows:

Leaking frequency = Number of leaking connectors (E-2)

n

Then, the confidence level of the sample size can be calculated

using the following equation, based upon a hypergeometric

distribution:

P=1- (N-D’)! (N-n)! (E-3)

N! (N-D’-n)!

where:

N = Total population of connectors;

n = Sample size; and

D’ = Number of leaking connectors × N

n

If ’p’ calculated in this manner is less than 0.95, then a less

than 95 percent confidence exists that the screening value

distribution has been properly identified. Therefore, additional

connectors must be screened to achieve a 95 percent confidence

level. The number of additional connectors required to satisfy

the requirement for a 95 percent confidence level can be

calculated by solving Equation (E-1) again, using the leak

frequency calculated in Equation (E-2), and subtracting the

E-2
Figure E-1. Fraction of Leaking Connectors at Several Leak

Definitions

E-3
original sample size. After this additional number of connectors

have been screened, the revised fraction of leaking components

and the confidence level of the new sample size (i.e., the

original sample size plus the additional connectors screened)

should be recalculated using Equation (E-3). The Agency requires

sufficient screening to achieve a 95 percent confidence level,

until a maximum of 50 percent of the total number of connectors

in the process unit have been screened. The EPA believes that

50 percent of the total connector population is a reasonable

upper limit for a sample size. If half of the total number of

connectors are screened, no further connector screening is

necessary, even if a 95 percent confidence level has not been

achieved.

E-4
APPENDIX F

REFERENCE METHOD 21

(Code of Federal Regulations, Title 40, Part 60,

Appendix A. Reference Method 21, Determination of

Volatile Organic Compound Leaks. Washington, D.C.,

U.S. Government Printing Office. Revised

June 22, 1990.)
EMISSION MEASUREMENT TECHNICAL INFORMATION CENTER

NSPS TEST METHOD

(EMTIC M-21, 2/9/93)

Method 21 - Determination of Volatile Organic Compound Leaks

1. APPLICABILITY AND PRINCIPLE

1.1 Applicability. This method applies to the determination of

volatile organic compound (VOC) leaks from process equipment.

These sources include, but are not limited to, valves, flanges

and other connections, pumps and compressors, pressure relief

devices, process drains, open-ended valves, pump and compressor

seal system degassing vents, accumulator vessel vents, agitator

seals, and access door seals.

1.2 Principle. A portable instrument is used to detect VOC

leaks from individual sources. The instrument detector type is

not specified, but it must meet the specifications and

performance criteria contained in section 3. A leak definition

concentration based on a reference compound is specified in each

applicable regulation. This procedure is intended to locate and

classify leaks only, and is not to be used as a direct measure of

mass emission rate from individual sources.

2. DEFINITIONS

2.1 Leak Definition Concentration. The local VOC concentration

at the surface of a leak source that indicates that a VOC

emission (leak) is present, The leak definition is an instrument

meter reading based on a reference compound.

2.2 Reference Compound. The VOC species selected as an

instrument calibration basis for specification of the leak

definition concentration. (For example, if a leak definition

concentration is 10,000 ppm as methane, then any source emission

that results in a local concentration that yields a meter reading

of 10,000 on an instrument meter calibrated with methane would be

classified as a leak. In this example, the leak definition is

10,000 ppm, and the reference compound is methane.)

2.3 Calibration Gas. The VOC compound used to adjust the

instrument meter reading to a known value. The calibration gas

is usually the reference compound at a known concentration

approximately equal to the leak definition concentration.

2.4 No Detectable Emission. The total VOC concentration at the

surface of a leak source that indicates that a VOC emission

(leak) is not present. Since background VOC concentrations may

exist, and to account for instrument drift and imperfect

reproducibility, a difference between the source surface

F-1
concentration and the local ambient concentration is determined.

A difference based on the meter readings of less than a

concentration corresponding to the minimum readability

specification indicates that a VOC emission (leak) is not

present. (For example, if the leak definition in a regulation is

10,000 ppm, then the allowable increase is surface concentration

versus local ambient concentration would be 500 ppm based on the

instrument meter readings.)

2.5 Response Factor. The ratio of the known concentration of a

VOC compound to the observed meter reading when measured using an

instrument calibrated with the reference compound specified in

the applicable regulation.

2.6 Calibration Precision. The degree of agreement between

measurements of the same known value, expressed as the relative

percentage of the average difference between the meter readings

and the known concentration to the known concentration.

2.7 Response Time. The time interval from a step change in VOC

concentration at the input of the sampling system to the time at

which 90 percent of the corresponding final value is reached as

displayed on the instrument readout meter.

3. APPARATUS

3.1 Monitoring Instrument.

3.1.1 Specifications

a. The VOC instrument detector shall respond to the compounds

being processed. Detector types which may meet this requirement

include, but are not limited to, catalytic oxidation, flame

ionization, infrared absorption, and photoionization.

b. The instrument shall be capable of measuring the leak

definition concentration specified in the regulation.

c. The scale of the instrument meter shall be readable to +

or - 5 percent of the specified leak definition concentration.

d. The instrument shall be equipped with a pump so that a

continuous sample is provided to the detector. The nominal

sample flow rate shall be 0.1 to 3.0 liters per minute.

e. The instrument shall be intrinsically safe for operation in

explosive atmospheres as defined by the applicable U.S.A.

standards (e.g., National Electrical Code by the National Fire

Prevention Association).

f. The instrument shall be equipped with a probe or probe

extension for sampling not to exceed 1/4 in. in outside diameter,

with a single end opening for admission of sample.

F-2
3.1.2 Performance Criteria.

a. The instrument response factors for the individual compounds

to be measured must be less than 10.

b. The instrument response time must be equal to or less than

30 seconds. The response time must be determined for the

instrument configuration to be used during testing.

c. The calibration precision must be equal to or less than

10 percent of the calibration gas value.

d. The evaluation procedure for each parameter is given in

section 4.4.

3.1.3 Performance Evaluation Requirements.

a. A response factor must be determined for each compound that

is to be measured, either by testing or from reference sources.

The response factor tests are required before placing the

analyzer into service, but do not have to be repeated at

subsequent intervals.

b. The calibration precision test must be completed prior to

placing the analyzer into service, and at subsequent 3-month

intervals or at the next use whichever is later.

c. The response time test is required before placing the

instrument into service. If a modification to the sample pumping

system or flow configuration is made that would change the

response time, a new test is required before further use.

3.2 Calibration Gases.

The monitoring instrument is calibrated in terms of parts

per million by volume (ppm) of the reference compound specified

in the applicable regulation. The calibration gases required for

monitoring and instrument performance evaluation are a zero gas

(air, less than 10 ppm VOC) and a calibration gas in air mixture

approximately equal to the leak definition specified in the

regulation. If cylinder calibration gas mixtures are used, they

must be analyzed and certified by the manufacturer to be within +

or - 2 percent accuracy, and a shelf life must be specified.

Cylinder standards must be either reanalyzed or replaced at the

end of the specified shelf life. Alternatively, calibration

gases may be prepared by the user according to any accepted

gaseous preparation procedure that will yield a mixture accurate

to within + or - 2 percent. Prepared standards must be replaced

each day of use unless it can be demonstrated that degradation

does not occur during storage.

Calibrations may be performed using a compound other than

the reference compound if a conversion factor is determined for

that alternative compound so that the resulting meter readings

F-3
during source surveys can be converted to reference compound

results.

4. PROCEDURES

4.1 Pretest Preparations. Perform the instrument evaluation

procedure given in section 4.4 if the evaluation requirement of

section 3.1.3 have not been met.

4.2 Calibration Procedures. Assemble and start up the VOC

analyzer according to the manufacturer’s instructions. After the

appropriate warmup period and zero internal calibration

procedure, introduce the calibration gas into the instrument

sample probe. Adjust the instrument meter readout to correspond

to the calibration gas value. (Note: If the meter readout cannot

be adjusted to the proper value, a malfunction of the analyzer is

indicated and corrective actions are necessary before use.)

4.3 Individual Source Surveys.

4.3.1 Type I - Leak Definition Based on Concentration. Place

the probe inlet at the surface of the component interface where

leakage could occur. Move the probe along the interface

periphery while observing the instrument readout. If an

increased meter reading is observed, slowly sample the interface

where leakage is indicated until the maximum meter reading is

obtained. Leave the probe inlet at this maximum reading location

for approximately two times the instrument response time. If the

maximum observed meter reading is greater than the leak

definition in the applicable regulation, record and report the

results as specified in the regulation reporting requirements.

Examples of the application of this general technique to specific

equipment types are:

a. Valves - Leaks usually occur at the seal between the stem

and the housing. Place the probe at the interface where the stem

exits the packing and sample the stem circumference and the

flange periphery. Survey valves of multipart assemblies where a

leak could occur.

b. Flanges and Other Connections - Place the probe at the outer

edge of the flange-gasket interface and sample the circumference

of the flange.

c. Pump or Compressor Seals - If applicable, determine the type

of shaft seal. Perform a survey of the local area ambient VOC

concentration and determine if detectable emissions exist as

described above.

d. Pressure Relief Devices - For those devices equipped with an

enclosed extension, or horn, place the probe inlet at

approximately the center of the exhaust area to the atmosphere.

F-4
e. Process Drains - For open drains, place the probe inlet as

near as possible to the center of the area open to the

atmosphere. For covered drains, locate probe at the surface of

the cover and traverse the periphery.

f. Open-ended Lines or Valves - Place the probe inlet at

approximately the center of the opening of the atmosphere.

g. Seal System Degassing Vents, Accumulator Vessel Vents,

Pressure Relief Devices - If applicable, observe whether the

applicable ducting or piping exists. Also, determine if any

sources exist in the ducting or piping where emissions could

occur before the control device. If the required ducting or

piping exists and there are no sources where the emissions could

be vented to the atmosphere before the control device, then it is

presumed that no detectable emissions are present. If there are

sources in the ducting or piping where emissions could be vented

or sources where leaks could occur, the sampling surveys

described in this section shall be used to determine if

detectable emissions exist.

h. Access door seals - Place the probe inlet at the surface of

the door seal interface and traverse the periphery.

4.3.2 Type II - "No Detectable Emission". Determine the

ambient concentration around the source by moving the probe

randomly upwind and downwind around one to two meters from the

source. In case of interferences, this determination may be made

closer to the source down to no closer than 25 centimeters. Then

move the probe to the surface of the source and measure as in

4.3.1. The difference in these concentrations determines whether

there are no detectable emissions. When the regulation also

requires that no detectable emissions exist, visual observations

and sampling surveys are required. Examples of this technique

are: (a) Pump or Compressor Seals - Survey the local area ambient

VOC concentration and determine if detectable emissions exist.

(b) Seal System Degassing Vents, Accumulator Vessel Vents,

Pressure Relief Devices - Determine if any VOC sources exist

upstream of the device. If such ducting exists and emissions

cannot be vented to the atmosphere upstream of the control

device, then it is presumed that no detectable emissions are

present. If venting is possible sample to determine if

detectable emissions are present.

4.3.3 Alternative Screening Procedure.

4.3.3.1 A screening procedure based on the formation of bubbles

in a soap solution that is sprayed on a potential leak source may

be used for those sources that do not have continuously moving

parts, that do not have surface temperatures greater than the

boiling point or less than the freezing point of the soap

solution, that do not have open areas to the atmosphere that the

soap solution cannot bridge, or that do not exhibit evidence of

F-5
liquid leakage. Sources that have these conditions present must

be surveyed using the instrument technique of section 4.3.1 or

4.3.2.

4.3.3.2 Spray a soap solution over all potential leak sources.

The soap Solution may be a commercially available leak detection

solution or may be prepared using concentrated detergent and

water.

A pressure sprayer or squeeze bottle may be used to dispense the

solution. Observe the potential leak sites to determine if any

bubbles are formed. If no bubbles are observed, the source is

presumed to have no detectable emissions or leaks as applicable.

If any bubbles are observed, the instrument techniques of section

4.3.1 or 4.3.2 shall be used to determine if a leak exists, or if

the source has detectable emissions, as applicable.

4.4 Instrument Evaluation Procedures. At the beginning of the

instrument performance evaluation test, assemble and start up the

instrument according to the manufacturer’s instructions for

recommended warmup period and preliminary adjustments.

4.4.1 Response Factor.

4.4.1.1 Calibrate the instrument with the reference compound as

specified in the applicable regulation. For each organic species

that is to be measured during individual source surveys, obtain

or prepare a known standard in air at a concentration of

approximately 80 percent of the applicable leak definition unless

limited by volatility or explosivity. In these cases, prepare a

standard at 90 percent of the standard saturation concentration,

or 70 percent of the lower explosive limit, respectively.

Introduce this mixture to the analyzer and record the observed

meter reading. Introduce zero air until a stable reading is

obtained. Make a total of three measurements by alternating

between the known mixture and zero air. Calculate the response

factor for each repetition and the average response factor.

4.4.1.2 Alternatively, if response factors have been published

for the compounds of interest for the instrument or detector

type, the response factor determination is not required, and

existing results may be referenced. Examples of published

response factors for flame ionization and catalytic oxidation

detectors are included in the Bibliography.

4.4.2 Calibration Precision. Make a total of three measurements

by alternately using zero gas and the specified calibration gas.

Record the meter readings. Calculate the average algebraic

difference between the meter readings and the known value.

Divide this average difference by the known calibration value and

multiply by 100 to express the resulting calibration precision as

a percentage.

F-6
4.4.3 Response Time. Introduce zero gas into the instrument

sample probe. When the meter reading has stabilized, switch

quickly to the specified calibration gas. Measure the time from

switching to when 90 percent of the final stable reading is

attained. Perform this test sequence three times and record the

results. Calculate the average response time.

5. BIBLIOGRAPHY

1. Dubose, D.A., and G.E. Harris. Response Factors of VOC

Analyzers at a Meter Reading of 10,000 ppmv for Selected Organic

Compounds. U.S. Environmental Protection Agency, Research

Triangle

Park, NC. Publication No. EPA 600/2-81051. September 1981.

2. Brown, G.E., et al. Response Factors of VOC Analyzers

Calibrated with Methane for Selected Organic Compounds. U.S.

Environmental Protection Agency, Research Triangle Park, NC.

Publication No. EPA 600/2-81-022. May 1981.

3. DuBose, D.A. et al. Response of Portable VOC Analyzers to

Chemical Mixtures. U.S. Environmental Protection Agency,

Research Triangle Park, NC. Publication No. EPA 600/2-81-110.

September 1981.

F-7
APPENDIX G

DEVELOPMENT OF LEAK RATE

VERSUS FRACTION LEAKING EQUATIONS

AND DETERMINATION OF LDAR CONTROL EFFECTIVENESS
APPENDIX G

The purpose of this appendix is to provide additional

information on the approach used to develop the average leak rate

versus fraction leaking equations presented in chapter 5.0.

Also, background information is presented on the determination of

control effectiveness of LDAR programs at SOCMI process units and

refinery process units.

G.1 DEVELOPMENT OF AVERAGE LEAK RATE VERSUS FRACTION LEAKING

EQUATIONS

In chapter 5.0, tables 5-4 and 5-5 present equations that

predict average leak rate based on the fraction leaking at SOCMI

process units and refinery process units, respectively.

Equations are presented for gas valves, light liquid valves,

light liquid pumps, and connectors, and each of the equations are

plotted in figures 5-1 through 5-8.

The equations are expressed in the following format:

Average Leak Rate = (Slope × Fraction Leaking) + Intercept

The average leak rate has units of kilograms per hour per source.

The fraction leaking is the fraction of sources that screen

greater than or equal to the applicable leak definition. The

leak definition is the screening value at which a leak is

indicated. (For example an equipment leak regulation may have a

leak definition of 10,000 ppmv.) Equations were developed for

several possible leak definitions.

Using the applicable equation, if it is known what

percentage of sources screen greater than or equal to the leak

definition, then an overall average leak rate for all sources can

be estimated. If the fraction leaking before and after an LDAR

program is implemented are known, then the average leak rates

before and after the program can be determined. These average

leak rates before and after the program are used to calculate the

control efficiency of the program.

G-1
The leak rate versus fraction leaking equations were

developed using the following procedure:

STEP 1: Determine average emission factors for

(1) screening values greater than or equal to the

applicable leak definition, and (2) screening

values less than the applicable definition.

STEP 2: The average emission factor for screening values

less than the leak definition is the intercept in

the equation.

STEP 3: The average emission factor for screening values

greater than or equal to the leak definition minus

the average emission factor for screening values

less than the leak definition is the slope in the

equation.

An example of the above steps is presented for gas valves in a

SOCMI process units for a leak definition of 10,000 ppmv. From

table 2-4 the gas valve >10,000 ppmv emission factor is

0.0782 kg/hr and the <10,000 ppmv factor is 0.000131 kg/hr.

Thus, the equation relating average leak rate to fraction leaking

for SOCMI gas valves with a leak definition of 10,000 ppmv is as

follows:

Avg Leak Rate (kg/hr) = [(0.0782-0.000131) × FL] + 0.000131

= (0.0781 × FL) + 0.000131

where:

FL = Fraction leaking.

Notice that when applying the above equation if 100 percent of

the gas valves screened less than 10,000 ppmv, the equation

predicts an average leak rate equal to the <10,000 ppmv factor.

Similarly, if 100 percent of sources screened greater than or

equal to 10,000 ppmv, the equation predicts an average leak rate

equal to the >10,000 ppmv factor.

For SOCMI process units, equations were developed for each

of the equipment types for leak definitions of 500 ppmv,

1,000 ppmv, 2,000 ppmv, 5,000 ppmv, and 10,000 ppmv. For each of

the leak definitions, the greater than or equal to factors and

the less than factors were developed by entering the applicable

G-2
screening data from the combined screening data set into the

applicable revised SOCMI correlation equation (see appendix B).

For example, the <500 ppmv factor for connectors was estimated by

entering all connector screening data with values less than

500 ppmv from the combined screening dataset into the revised

SOCMI connector correlation equation. The sum of total emissions

divided by the number of screening values gives the <500 ppmv

connector average emission factor.

For refinery process units, equations were developed for

each of the equipment types for leak definitions of 500 ppmv,

1,000 ppmv and 10,000 ppmv. The refinery >10,000 ppmv and

<10,000 ppmv emission factors had previously been developed and

are presented in table 2-5. The same approach used to develop

the >10,000/<10,000 ppmv refinery factors was used to develop the

factors for leak definitions of 500 ppmv and 1,000 ppmv. This

approach involves using information from the Refinery Assessment

Study (EPA-600/2-80-075c) on the cumulative distribution of

emissions and screening values.

G.2 CONTROL EFFECTIVENESS CALCULATIONS

In addition to the equations described in section G.1,

chapter 5.0 presents estimated control effectiveness values at

SOCMI and refinery process units for control equivalent to:

(1) Monthly LDAR program with a leak definition of

10,000 ppmv;

(2) Quarterly LDAR program with a leak definition of

10,000 ppmv; and

(3) Control equivalent to the LDAR program required by the

proposed hazardous organic NESHAP equipment leaks

negotiated regulation.

Tables G-1 and G-2 summarize how the control effectiveness values

of the above LDAR programs were determined for SOCMI and refinery

process units, respectively.

The approach for calculating the control effectiveness of a

LDAR program is discussed in detail in chapter 5.0. The approach

involves determining the average leak rate before and after the

LDAR program is implemented. The average leak rates before and

G-3
TABLE G-1. DETERMINATION OF LDAR CONTROL EFFECTIVENESS AT SOCMI PROC

Equipment

type

Controlprogram

Leak

definition

(ppmv)

Initial leak

fraction

(percent)

Initial

leak rate

(kg/hr)

Steady-state leak fraction after LDAR

implemented (percent)

Immediately

after LDAR

monit.

Immediately

prior to

LDAR monit.

Cycle

average

LL Valves Monthly 10000 4.3 0.0040 0.20 0.88 0.54 

Quarterly 10000 4.3 0.0040 0.59 2.61 1.60 

HON reg neg 500 8.5 0.0040 0.00 2.00 1.00 

Gas Valves Monthly 10000 7.5 0.0060 0.29 1.29 0.79 

Quarterly 10000 7.5 0.0060 0.86 3.80 2.33 

HON reg neg 500 13.6 0.0060 0.00 2.00 1.00 

LL Pumps Monthly 10000 7.5 0.0199 0.00 3.53 1.77 

Quarterly 10000 7.5 0.0199 0.00 7.50 3.75 

HON reg neg 1000 17.1 0.0199 0.00 8.04 4.02 

Connectors HON reg neg 500 3.9 0.0018 0.00 0.50 0.25 

G-4
TABLE G-2. DETERMINATION OF LDAR CONTROL EFFECTIVENESS AT REFINERY PRO

Equipment

type

Controlprogram

Leak

definition

(ppmv)

Initial leak

fraction

(percent)

Initial

leak rate

(kg/hr)

Immediately

after LDAR

monit.

Immediately

prior to

LDAR monit.

Cycle

average

le

(

LL Valves Monthly 10000 11.0 0.0109 0.39 1.72 1.06 0

Quarterly 10000 11.0 0.0109 1.15 5.07 3.11 0

HON reg neg 500 28.5 0.0109 0.00 2.00 1.00 0

Gas Valves Monthly 10000 10.0 0.0268 0.36 1.60 0.98 0

Quarterly 10000 10.0 0.0268 1.06 4.69 2.88 0

HON reg neg 500 24.0 0.0268 0.00 2.00 1.00 0

LL Pumps Monthly 10000 24.0 0.1140 0.00 11.28 5.64 0

Quarterly 10000 24.0 0.1140 0.00 24.00 12.00 0

HON reg neg 1000 48.0 0.1140 0.00 10.00 5.00 0

G-5

Connectors HON reg neg 500 1.7 0.00025 0.00 0.50 0.25 0
after implementing the LDAR program are estimated by entering the

fraction leaking before and after implementing the program into

the equations described in section G.1.

For SOCMI process units, the fraction leaking before

implementing the LDAR program was based on the percentage of

equipment screening above the applicable leak definition in the

combined SOCMI screening dataset. (See appendix B.) Similarly,

the initial fraction leaking for refinery process units was based

on data from the Refinery Assessment Study on the percentage of

equipment screening above the applicable leak definition. Note

that each of the initial leak fractions predict leak rates equal

to the applicable SOCMI or refinery average emission factors

(tables 2-1 and 2-2) when entered into the applicable equation

described in section G.1. In other words, when estimating the

control effectiveness for the SOCMI and refinery LDAR programs,

it has been assumed that prior to implementing the program

equipment leak emissions are equivalent to emissions that would

be predicted by the average emission factors.

The fraction leaking after implementing the LDAR program is

assumed to be the average of the "steady-state" fraction leaking

immediately before and after a monitoring cycle (see discussion

in chapter 5.0). The following parameters are used to estimate

the steady-state leak fractions:

recurrence rate,

unsuccessful repair rate, and

occurrence rate.

The values used for these parameters are summarized in

table G-3 for both SOCMI and refinery process units.

The paragraphs below summarize the approach used to

determine the above parameters. First, the approach used to

determine the parameters in a program with a leak definition of

10,000 ppmv is described. Then, the approach used to determine

the parameters in a program equivalent to the proposed hazardous

organic NESHAP equipment leaks negotiated regulation is

described.

G-6
TABLE G-3. PARAMETERS USED TO CALCULATE STEADY-STATE LEAK

FRACTION AFTER LDAR PROGRAM IS IMPLEMENTED

Equipment type

Control

program

Leak

definition

(ppmv)

Recurrence

ratea

(percent)

Unsuccessful

repair ratea

(percent)

Initial leak

fractionb

(percent)

Occurrence

ratec

(percent)

PARAMETER VALUES FOR SOCMI PROCESS UNITS

LL Valves Monthly 10000 14 10 4.3 0.68

Quarterly 10000 14 10 4.3 2.03

HON reg neg 500 0 0 8.5 2.00

Gas Valves Monthly 10000 14 10 7.5 1.00

Quarterly 10000 14 10 7.5 2.97

HON reg neg 500 0 0 13.6 2.00

LL Pumps Monthly 10000 0 0 7.5 3.53

Quarterly 10000 0 0 7.5 7.50

HON reg neg 1000 0 0 17.1 8.04

Connectors HON reg neg 500 0 0 3.9 0.50

PARAMETER VALUES FOR REFINERY PROCESS UNITS

LL Valves Monthly 10000 14 10 11.0 1.34

Quarterly 10000 14 10 11.0 3.97

HON reg neg 500 0 0 28.5 2.00

Gas Valves Monthly 10000 14 10 10.0 1.24

Quarterly 10000 14 10 10.0 3.67

HON reg neg 500 0 0 24.0 2.00

LL Pumps Monthly 10000 0 0 24.0 11.28

Quarterly 10000 0 0 24.0 24.00

HON reg neg 1000 0 0 48.0 10.00

Connectors HON reg neg 500 0 0 1.7 0.50

a The recurrence rate and unsuccessful repair rate for valves and pumps in LDAR programs with a leak

definition of 10,000 ppmv was obtained from the SOCMI Fugitives AID (EPA-450/3-82-010). For the HON

reg neg, a simplifying assumption was made that the recurrence rate and unsuccessful repair rate equal

zero percent for all equipment types.

b The initial leak fraction for SOCMI process units is based on the combined screening dataset. The initial

leak fraction for refinery process units is based on data collected in the Refinery Assessment Study

(EPA-600/2-8--075c).

c The occurrence rate for LDAR programs with a leak definition of 10,000 ppmv is calculated as a function of

the initial leak fraction. The relationship is based on data collected in the Six Unit Maintenance Study

(EPA-600/S2-081-080). The equations for valves and pumps are as follows:

Valve 30 Day Occurrence rate = 0.0976 * leak fraction + 0.264.

Pump 30 Day Occurrence rate = 0.47 * leak fraction.

The quarterly occurrence rate is approximately 3 times the 30-day occurrence rate. In cases where the

quarterly occurrence rate exceeded the initial leak fraction, it was set equal to the initial leak

fraction. The occurrence rate for the HON reg neg LDAR programs is set equal to the performance level,

except for pumps in SOCMI process units. For pumps in SOCMI process units the occurrence rate is

calculated using the equation above.

G-7
G.2.1 LDAR Program with Leak Definition of 10,000 ppmv.

Estimates for the recurrence rate and unsuccessful repair

rate were obtained from the Fugitive Emissions Additional

Information document (EPA-450/3-82-010). In this document, data

collected for LDAR programs with a leak definition of 10,000 ppmv

were summarized. It was concluded that the recurrence rate for

valves was 14 percent and the unsuccessful repair rate for valves

10 percent. It was assumed that all pumps are replaced with a

new seal and for that reason the recurrence rate and unsuccessful

repair rate for pumps were both assumed equal to zero percent

(i.e., all pumps are successfully repaired and leaks do not

recur). Data were unavailable for connectors for an LDAR program

with a leak definition of 10,000 ppmv, and, for this reason,

control efficiency for connectors in an LDAR program with a leak

definition of 10,000 ppmv have not been estimated.

Estimates for the occurrence rate were based on data

collected in the Six Unit Maintenance Study (EPA-600/S2-081-080).

Data from this study indicated that the occurrence rate is a

function of the initial leak fraction. For valves this

relationship was expressed by the following equation:

OCCvalve = 0.0976 (LF) + 0.264

where:

OCCvalve = Monthly occurrence rate for valves;

and

LF = Initial leak fraction.

For pumps, the relationship was as follows:

OCCpump = 0.47 × LF

where:

OCCpump = Monthly occurrence rate for pumps; and

LF = Initial leak fraction.

G-8
For both pumps and valves, the monthly occurrence rate was used

to estimate the quarterly occurrence rate using the following

equation:

Q = M + M (1 - M) + M {1 - [M + M (1 - M)]}

where:

M = Monthly occurrence rate; and

Q = Quarterly occurrence rate.

Note that in cases where the estimated quarterly occurrence rate

exceeded the initial leak fraction, it was set equal to the

initial leak fraction.

G.2.2 Control Equivalent to the LDAR Program Required by the

Proposed Hazardous Organic NESHAP Equipment Leaks

Negotiated Regulation

For each of the equipment types, the proposed hazardous

organic NESHAP LDAR program requirements include a performance

level requirement. This performance level specifies the

allowable leak fraction once the program is in place. For

example, the performance level for valves is 2 percent. Because

the proposed hazardous organic NESHAP rule contains the

performance level requirement and because limited data are

available on LDAR programs with the leak definitions of the

proposed hazardous organic NESHAP rule, simplifying assumptions

were made when estimating the recurrence rate, unsuccessful

repair rate, and occurrence rate.

For each of the equipment types, it was assumed that the

recurrence rate and unsuccessful repair rate were equal to zero

percent. These two parameters have the least impact on the

predicted control efficiency.

For valves and connectors, the proposed hazardous organic

NESHAP rule allows for reduced monitoring frequency if the leak

fraction remains below the performance level. For this reason,

it was assumed that process units would monitor valves and

connectors at whatever monitoring frequency (i.e., monthly,

quarterly, annually, etc.) that allows them to meet the

performance level. Thus, for valves and connectors the

G-9
occurrence rate was set equal to the performance level. Note

that in cases where process units remain below the performance

level this may overestimate the occurrence rate. However, this

is offset by the assumption that the recurrence rate and

unsuccessful repair rate are equal to zero percent.

For pumps the proposed hazardous organic NESHAP rule

requires monthly monitoring. For this reason the occurrence rate

was calculated using the same equation for pumps as presented in

section G.2.1 for LDAR programs with a leak definition of

10,000 ppmv. Note, however, that the initial leak fraction used

in the equation was the leak fraction associated with the leak

definition of the proposed hazardous organic NESHAP rule

(1,000 ppmv). For refineries, the predicted occurrence rate for

pumps exceeded the performance level, and for this reason the

occurrence rate was set equal to the performance level.

G-10
TECHNICAL REPORT DATA

(Please read Instructions on the reverse before completing)

1. Report No.

EPA-453/R-95-017 2. 3. RECIPIENT’S ACCESSION NO.

4. TITLE AND SUBTITLE

1995 Protocol for Equipment Leak Emission

Estimates

5. REPORT DATA

November 1995

6. PERFORMING ORGANIZATION CODE

7. AUTHOR(S)

David L. Epperson

8. PERFORMING ORGANIZATION REPORT NO.

DCN: 95-652-015-55-05

9. PERFORMING ORGANIZATION NAME AND ADDRESS

Radian Corporation

P.O. Box 13000

Research Triangle Park, NC 27709

10. PROGRAM ELEMENT NO.

11. CONTRACT/GRANT NO.

68-D1-0117, WA 155

12. SPONSORING AGENCY NAME AND ADDRESS

Director, Office of Air Quality Planning

and Standards

U.S. Environmental Protection Agency

Research Triangle Park, N.C. 27711

13. TYPE OF REPORT AND PERIOD COVERED

14. SPONSORING AGENCY

EPA/200/04

15. SUPPLEMENTARY NOTES

Project Officer is David W. Markwordt, Mail Drop 13

(919)-541-0837

16. ABSTRACT

The report presents standard protocols for estimating mass

emissions from equipment leaks. Different approaches for

estimating equipment leak emissions are described and several

topics relevant to estimating equipment leak emissions (such as

speciating emissions) are addressed. Information on how to

perform a screening survey at a process unit is presented.

Information on how a process unit can collect equipment leak

rate data by enclosing individual equipment pieces and

measuring mass emissions is provided. Also, information if

provided that can be used to estimate the control efficiency of

equipment leak control techniques. The document will help

facilities generate accurate plant-specific equipment leak

emission estimates.

17. KEY WORDS AND DOCUMENT ANALYSIS

a. DESCRIPTORS b. IDENTIFIERS/OPEN ENDED TERMS c. COSATI Field/Group

Synthetic Organic Chemical

Manufacturing

Petroleum Refining

Organic Compounds

Fugitive Emissions

Equipment Leaks

Response Factors

Screening Data

Bagging Data

Leak Detection and

Repair

18. DISTRIBUTION STATEMENT

Release to Public

19. SECURITY CLASS (This Report)

Unclassified

21. NO. OF PAGES

400

20. SECURITY CLASS (This page)

Unclassified

22. PRICE

EPA Form 2220-1 (Rev. 4-77) PREVIOUS EDITION IS OBSOLETE