United States Enforcement and EPA/305/B-98/011 

Environmental Protection Compliance Assurance December 1998 

Agency (2224A) 

Inspection Manual: 

Federal Equipment Leak 

Regulations for the 

Chemical Manufacturing 

Industry 

Volume I: Inspection 

Manual 

EPA Office of Compliance 

Chemical, Commercial 

Services, and Municipal 

Division 

ABSTRACT

The purpose of this manual is to enhance an inspector’s ability to conduct more complete 

and effective inspections at facilities in the chemical industry that are subject to Federal 

equipment leak regulations. Equipment leak standards are designed to reduce or eliminate 

emissions of volatile organic compounds (VOCs), volatile hazardous air pollutants 

(VHAPs), and organic HAPs from the miles of piping and numerous components found in 

chemical manufacturing processes. 

This document is divided into three volumes. The first volume is a manual for inspectors; 

the second and third volumes describe regulations that apply to the chemical 

manufacturing and the petroleum refining industries, respectively. 

Volume I has five chapters dedicated to helping an inspector: 

C Chapter 1 states the goals, background, approaches to rule enforcement, and 

organization of the document. 

C Chapter 2 addresses applicability determinations: ensuring the correct rules are 

being complied with at a facility, determining whether all appropriate components 

have been identified, and ensuring the components are properly classified by 

service. 

C Chapter 3 discusses reporting and recordkeeping requirements for NSPS, 

NESHAP, HON, and RCRA (recordkeeping only), and strategies for reviewing 

reports and records. 

C Chapter 4 covers on-site inspections: walk-throughs and inspections with the 

inspector monitoring for leaks. It addresses pre-inspection activities, timing and 

scope, interviews, leak monitoring evaluations, inspections of the process area and 

records, and post-inspection reviews and reports. 

C Chapter 5 discusses recommended inspection techniques and procedures. 

Volume II tackles the equipment leak regulations applicable to the chemical manufacturing 

industry. 

C The first three appendices of Volume II summarize the regulations of 40 CFR 

Part 60 Subpart VV, Part 61 Subparts J and V, Part 63 Subparts H and I, Part 

264 Subpart BB, and Part 265 Subpart BB; detail the differences among the 

regulations; and give the requirements grouped by component. 

C Appendix D describes the regulated equipment.

C Appendix E contains the “Method 21" approach to leak detection.

C Appendix F lists chemical manufacturing processes that are subject to HON.

C Appendix G lists organic HAPs that are subject to HON.

C Appendix H lists manufacturing processes and associated organic HAP

emissions that are subject to HON. 
Volume III contains the equipment leak regulations applicable to the petroleum refining 

industry. 

C The three appendices of Volume III summarize the regulations of 40 CFR Part 60 

Subparts DDD, GGG, KKK, and QQQ, and Part 63 Subpart CC; detail the 

differences among the regulations; and give the requirements grouped by 

component. 
CONTENTS

VOLUME I: INSPECTION MANUAL

Page 

Chapter 1 Statement of Goals, Background, Approaches 

to Rule Enforcement, and Organization of 

Document ........................................... . 1- 1

1.1 Scope of Manual and Statement of Purpose .................. . 1- 1

1.2 Background .......................................... . 1- 2

1.3 Approaches to Rule Enforcement .......................... . 1-12

1.4 Organization of Document ............................... . 1-13

Chapter 2 Applicability .......................................... . 2-1

2.1 Which Regulation? ...................................... . 2-1

2.2 Which Components? ..................................... . 2-6

2.3 Which Service? ......................................... . 2-7

Chapter 3 Compliance/Inspection Through Reports and 

Recordkeeping ....................................... . 3- 1

3.1 Reports ............................................. . 3- 1

3.2 Recordkeeping ........................................ . 3- 9

3.3 Strategies for Reviewing Reports and Procedures ............. . . 3-16

Chapter 4 Compliance/Assessment Through On-Site 

Inspections .......................................... . 4- 1

4.1 Walk-Through Inspections ............................... . 4- 1

4.2 Direct Monitoring of Components ......................... . 4-14

Chapter 5 Recommended Inspection Techniques and

Procedures ........................................... . 5-1

5.1 Inspection Program Development ........................... . 5-1

5.2 Working with Regulated Facilities .......................... . 5-3

Bibliography ..................................................... . 6-1
CONTENTS (continued) 

VOLUME II: CHEMICAL MANUFACTURING INDUSTRY REGULATIONS

Appendix A Equipment Leak Regulations: Side-by-Side Comparisons

Appendix B Equipment Leak Regulations: Summary of Differences

Appendix C Equipment Leak Regulations: Summary by Component

Appendix D Regulated Equipment

Appendix E Method 21 (40 CFR 60, Appendix A)

Appendix F Chemical Manufacturing Processes Subject to HON Standards (40

CFR 63, Subpart H) 

Appendix G Organic HAPs Subject to HON Standards (Subpart H) 

Appendix H Manufacturing Processes and Organic HAPs Subject to HON 

Standards (Subpart I) 

VOLUME III: PETROLEUM REFINING INDUSTRY REGULATIONS 

Appendix A Equipment Leak Regulations: Side-by-Side Comparisons 

Appendix B Equipment Leak Regulations: Summary of Differences 

Appendix C Equipment Leak Regulations: Summary by Component 
CHAPTER 1 

STATEMENT OF GOALS, BACKGROUND, APPROACHES TO RULE 

ENFORCEMENT, AND ORGANIZATION OF DOCUMENT 

1.1 SCOPE OF MANUAL AND STATEMENT OF PURPOSE 

The purpose of this manual is to provide guidance to enhance an inspector's ability 

to conduct more complete and effective inspections at facilities in the chemical industry 

subject to Federal equipment leak regulations. Inspections are typically conducted not 

only to determine whether a facility is in compliance with a regulation, but also to evaluate 

the effectiveness of a facility's implementation of a program. 

Equipment leak inspections involve two separate, but equally important activities: 

evaluation of equipment leak program records and reports and on-site inspections. To 

effectively conduct these activities, an inspector must be able to: 

• Determine which Federal equipment leak regulations are applicable to a 

chemical industry facility. 

• Understand the overall approach of using both equipment standards and 

leak detection and repair standards to achieve reductions in emissions from 

equipment leaks. 

• Determine if a source is complying with all the requirements of component 

identification, component marking, equipment design, monitoring, repair, 

recordkeeping, and reporting. 

• Understand the use of alternate standards. 

• Understand the volatile organic compounds (VOC) analyzer performance 

specifications required by U.S. EPA Method 21. 

• Understand the basic operating principles of flame ionization analyzers, 

photoionization analyzers, and catalytic combustion analyzers. 

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• Evaluate source personnel's calibration procedures and records. 

• Evaluate field monitoring procedures used by source personnel to detect 

leaks from regulated components. 

This manual addresses seven Federal equipment leak regulations that affect the 

chemical industry. These regulations, found in the Code of Federal Regulations (CFR), 

are: 

• 40 CFR Part 60, Subpart VV -- SOCMI Equipment Leaks New Source 

Performance Standard (NSPS) 

• 40 CFR Part 61, Subpart J -- Benzene Equipment Leaks National Emission 

Standard for Hazardous Air Pollutants (NESHAP) 

• 40 CFR Part 61, Subpart V -- NESHAP Equipment Leaks 

• 40 CFR Part 63, Subpart H -- Organic Hazardous Air Pollutants (HAP) 

Equipment Leak NESHAP 

• 40 CFR Part 63, Subpart I -- Organic HAP Equipment Leak NESHAP for 

Certain Processes 

• 40 CFR Part 264, Subpart BB -- Air Emission Standards for Equipment 

Leaks for TSDFs 

• 40 CFR Part 265, Subpart BB -- Air Emission Standards for Equipment 

Leaks for Interim Program TSDFs 

Due to the similarity among many of the equipment leak regulations, the guidance 

in this manual may be of assistance to inspectors responsible for conducting inspections at 

facilities complying with State or local equipment regulations and at other types of 

facilities (e.g., petroleum refineries) subject to other Federal equipment leak regulations. 

The focus of this manual, however, is the seven Federal regulations identified above, 

which affect facilities in the chemical industry. These regulations are presented in Volume 

II, Appendices A, B, and C. Regulations that affect the petroleum refinery industry are 

presented in Volume III. 

1.2 BACKGROUND 

1.2.1 Introduction: What are equipment leaks and why are they of concern? 

Chemical manufacturing processes include miles of piping and numerous 

components which convey petrochemical feedstocks, water, steam, and intermediate and 

final products. Emissions from equipment leaks occur in the form of gases or liquids that 

escape to the atmosphere through many types of connection points (e.g., flanges, threaded 

fittings, etc.) or through the moving parts of valves, pumps, compressors, pressure relief 

devices, and certain types of process equipment. 

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Equipment leaks are primarily defined within the above regulations on the basis of 

a detection instrument which reads the airborne concentration of volatile organic carbons 

at a potential leak point on a parts per million (ppm) basis. If the leak exceeds the 

threshold definition of the applicable regulation, repair of the leaking equipment is 

required. How the instrument is used (leak monitoring procedure) and performance 

criteria for the instrument are defined in Method 21 of 40 CFR Part 60, Appendix A (see 

Volume II, Appendix E). Equipment leaks also may be defined on the basis of visual 

observation of certain types of equipment. Each regulation includes leak definitions for 

specific types of equipment (see Volume II, Appendix C). 

Equipment leak standards are designed to reduce or eliminate emissions of VOCs, 

volatile hazardous air pollutants (VHAPs), and organic HAPs. VOCs, along with nitrogen 

oxides (NOx) and ultraviolet radiation, contribute to ozone production. Ozone is one of 

the criteria pollutants for which a national ambient air quality standard (NAAQS) is 

designated under Section 109 of the Clean Air Act, and nonattainment of the ozone 

NAAQS is a serious problem in the United States. VHAPs and organic HAPs 

(collectively referred to as HAPs in this document) are controlled because such air 

pollutants can pose a health risk for humans, in the form of direct worker exposure or as a 

contribution to air pollution affecting a broader population. 

Equipment leak emissions of VOCs and HAPs from the source categories 

discussed above constitute a significant source of air pollutants. For example, equipment 

leak emissions are estimated to be responsible for over 50 percent of the total VOC 

emissions from refineries or about 10,000 tons per year in California based on the 1990 

emissions inventory of the California Air Resources Board. Significant emissions from 

equipment leaks are also reported by the chemical manufacturing industries to the Toxic 

Chemical Release Inventory, as required by Section 313 of the Emergency Planning and 

Community Right-to-Know Act. For example, all manufacturers of chemicals and allied 

products (Standard Industrial Classification (SIC) Code 2800) reported in 1993 that 

fugitive emissions accounted for approximately 250,000 tons of air emissions. Fugitive 

emissions from equipment leaks are a significant subset of total fugitive emissions. 

Federal equipment leak standards implemented during the 1980's were estimated to 

reduce VOC and HAP emissions between 55 and 68 percent from facilities affected by the 

standards. For example, the EPA estimated the VOC emissions from facilities affected by 

the synthetic organic chemical manufacturing industry (SOCMI) standards would be 

reduced from approximately 91,500 tons per year (tpy) to 40,700 tpy--a 56 percent 

reduction. The emission reduction estimate for benzene sources at chemical 

manufacturing facilities is 68 percent. The Hazardous Organic NESHAP (HON) 

standards, as well as some State and local standards, are intended to achieve even greater 

reductions of VOC and HAP fugitive emissions. 

1.2.2 Components 

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A general set of equipment is covered by all of the equipment leak standards 

affecting chemical facilities. This includes pumps, compressors, pressure relief devices, 

open-ended valves or lines, valves, sampling connections, flanges and other connectors. 

In addition, all of the standards include any devices or systems (i.e., alarms, or dual 

mechanical seals) required to satisfy performance or equipment standards. The equipment 

leak standards also identify requirements for closed-vent systems and control devices that 

may be used to comply with the regulations. 

Additional equipment is covered only by specific standards. For example, product 

accumulator vessels are addressed only by the HON and benzene NESHAP, and agitators 

are addressed only by the HON. The HON also addresses instrumentation systems. 

Leak Detection and Repair (LDAR) programs (see Section 1.2.3.1) affect valves 

and pumps and other components. Appendix C in Volume II provides a component-bycomponent summary of the equipment leak regulations. Specific regulated components 

are discussed in greater detail in Volume II, Appendix D. 

1.2.2.1 Pumps 

Pumps are used extensively in chemical manufacturing facilities for moving fluids. 

The most widely used pump is the centrifugal pump. Other types of pumps that also may 

be used are the positive-displacement, reciprocating and rotary action, and special cannedmotor and diaphragm pumps. 

Chemicals transferred by pumps can leak at the point of contact between the 

moving shaft and stationary casing. To isolate the pump's interior from the atmosphere, 

all pumps, except the seal-less type (canned-motor and diaphragm), require a seal at the 

point where the shaft penetrates the housing. The most commonly used seals in these 

pumps are packed and mechanical. However, no seal system is perfect, and many pumps 

are equipped with a closed-vent system. 

1.2.2.2 Compressors 

Centrifugal, reciprocating, and rotary compressors are used in chemical 

manufacturing facilities. The centrifugal compressor uses a rotating element or series of 

elements containing curved blades to increase the pressure of a gas by centrifugal force. 

Reciprocating and rotary compressors increase pressure by confining the gas in a cavity 

and progressively decreasing the volume of the cavity. Reciprocating compressors usually 

use a piston and cylinder arrangement, while rotary compressors use rotating elements 

such as lobed impellers or sliding vanes. 

As with pumps, seals are required to prevent leakage from compressors. Rotary 

shaft seals for compressors may be labyrinth, restrictive carbon rings, mechanical contact, 

1-4
or liquid film. All of these seals are leak restriction devices, but none of them completely 

eliminate leakage. To respond to leakage, many compressors are equipped with ports in 

the seal area that evacuate collected gases to a control device. 

1.2.2.3 Pressure Relief Devices 

Engineering codes require the use of pressure-relieving devices or systems in 

applications where the process pressure may exceed the maximum allowable working 

pressure of the vessel. The pressure relief valve is the most common type of pressurerelieving device used. Typically, relief valves are spring-loaded and designed to open 

when the system pressure exceeds a set pressure, allowing the release of vapors or liquids 

until the system pressure is reduced to its normal operating level. When the normal 

pressure is re-attained, the valve reseats and a seal is again formed. The seal is a disc on a 

seat, and a leak through this seal is a potential source of fugitive VOC and HAP emissions. 

The potential causes of leakage from relief valves are "simmering or popping" (a condition 

that occurs when the system pressure comes close to the set pressure of the valve); 

improper reseating of the valve after a relieving operation; and corrosion or degradation of 

the valve seat. 

Rupture discs also may be used to relieve pressure in process units. These discs 

are made of a material that ruptures when a set pressure is exceeded, thus allowing the 

system to depressurize. The advantage of a ruptured disc is that the disc seals tightly and 

does not allow any emissions to escape from the system during normal operations. When 

the disc ruptures, however, the system will depressurize until atmospheric conditions are 

obtained, unless the disc is used with a pressure relief valve. 

1.2.2.4 Sampling Connections 

Process unit operations are checked periodically by routine analysis of feedstocks 

and products. To obtain representative samples for these analyses, sampling lines first 

must be purged. If the flushing liquid is not controlled, it could be drained onto the 

ground or into a process drain where it would evaporate and release emissions to the 

atmosphere. Closed-loop sampling systems control the purged process fluid by returning 

it directly to the process line, collecting and recycling the fluid, or transporting the fluid to 

a control device. 

1.2.2.5 Open-ended Lines or Open Valves 

Some valves are installed in a system so that they function with the downstream 

line open to the atmosphere. Open-ended lines, which are used mainly in intermittent 

service for sampling and venting, include purge, drain, and sampling lines. Some openended lines are needed to preserve product purity. Normally, these are installed between 

multi-use product lines to prevent products from collecting in cross-tie lines during valve 

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seat leakage. A faulty valve seat or incompletely closed valve would result in leakage 

through the valve, releasing emissions to the atmosphere. 

1.2.2.6 Process Valves 

One of the most common pieces of equipment affected by these standards is the 

process valve. Commonly used types are control, globe, gate, plug, ball, relief, and check 

valves. All except the relief valve (see Section 1.2.2.3) and check valve are activated 

through a valve stem, which may have either a rotational or linear motion, depending on 

the design. The valve stem requires a seal to isolate the process fluid inside the valve from 

the atmosphere. The possibility of a leak through this seal makes it a potential source of 

fugitive emissions. Since a check valve has no stem or subsequent packing gland, it is not 

considered a potential source of fugitive emissions and is not subject to the standards. 

The stem can be sealed to prevent leakage by using a packing gland or O-ring 

seals. Valves that require the stem to move in and out with or without rotation must use a 

packing gland. Conventional packing glands are suited for a wide variety of packing 

material. The most common are various types of braided asbestos that contain lubricants. 

Other packing materials include graphite, graphite-impregnated fibers, and 

tetrafluorethylene polymer. The packing material used depends on the valve application 

and configuration. These conventional packing glands can be used over a range of 

operating temperatures, but at high pressures, these glands must be quite tight to obtain a 

good seal. 

Elastomeric O-rings also are used for sealing process valves. These O-rings 

provide good sealing, but are not suitable if sliding motion occurs through the packing 

gland. These seals are used rarely in high pressure service, and operating temperatures are 

limited by the seal material. 

Bellows seals are more effective for preventing process fluid leaks than the 

conventional packing gland or any other gland-seal arrangement. This type of seal 

incorporates a formed metal bellows that makes a barrier between the disc and body 

bonnet joint. The bellows is the weak point of this type of system, and service life can be 

quite variable. Consequently, this type of seal normally is backed up with a conventional 

packing gland and often is fitted with a leak detector in case of failure. 

A diaphragm may be used to isolate the working parts of the valve and the 

environment from the process liquid. The diaphragm also may be used to control the flow 

of the process fluid. In this design, a compressor component pushes the diaphragm 

toward the valve bottom, throttling the flow. The diaphragm and compressor are 

connected in a manner so that separating them is impossible under normal working 

conditions. When the diaphragm reaches the valve bottom, it seats firmly against the 

bottom, forming a leak-proof seal. This configuration is recommended for fluids 

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containing solid particles and for medium-pressure service. Depending on the diaphragm 

material, this type of valve can be used at temperatures up to 205o

C and in severe acid 

solutions. If the seal fails, however, a valve using a diaphragm seal can become a source 

of fugitive emissions. 

1.2.2.7 Flanges and Other Connectors 

Flanges are bolted, gasket-sealed junctions used wherever pipes or other 

equipment such as vessels, pumps, valves, and heat exchangers may require isolation or 

removal. Connectors are all other nonwelded fittings that serve a similar purpose to 

flanges, which also allow bends in pipes (elbows), joining two pipes (couplings), or joining 

three or four pipes (tees or crosses). Connectors typically are threaded. 

Flanges may become fugitive emissions sources when leakage occurs because of 

improperly chosen gaskets or poorly assembled flanges. The primary cause of flange 

leakage is thermal stress, which causes deformation of the seal between the flange faces. 

Threaded connectors may leak if the threads become damaged or corroded or if tightened 

without sufficient lubrication or torque. 

1.2.2.8 Product Accumulator Vessels, Bottoms Receivers, and Separator 

Vessels 

Product accumulator vessels include overhead and bottoms receiver vessels used 

with fractionation columns and product separator vessels used in series with reactor 

vessels to separate reaction products. Accumulator vessels can be vented directly to the 

atmosphere or indirectly through a blowdown drum or vacuum system. When an 

accumulator vessel contains benzene and other HAPs and vents to the atmosphere, 

emissions will occur. 

1.2.2.9 Agitators 

Agitators are used to stir or blend chemicals. Like pumps and compressors, 

agitators may leak organic chemicals at the point where the shaft penetrates the casing. 

Consequently, seals are required to minimize fugitive emissions. Four seal arrangements 

commonly are used with agitators: compression packing (packed seal), mechanical seals, 

hydraulic seals, and lip seals. Packed seals for agitators are very similar in design and 

application to packed seals for pumps. 

Although mechanical seals are more costly than the other three types of seals, they 

offer a greatly reduced leakage rate to offset their higher cost. Furthermore, the 

maintenance frequency of mechanical seals is one-half to one-fourth that of packed seals. 

At pressures greater than 1,140 kPa (150 psig), the leakage rate and maintenance 

frequency are so superior that the use of packed seals on agitators is rare. As with packed 

1-7
seals, the mechanical seals for agitators are similar in design and application to the 

mechanical seals for pumps. 

1.2.2.10 Instrumentation Systems 

Instrumentation systems consist of smaller pipes and tubing that carry samples of 

process fluids to be analyzed to determine process operating conditions or to systems for 

measurement of process conditions. 

1.2.2.11 Closed-Vent Systems and Control Devices 

A closed-vent system can be used to collect and dispose of gaseous emissions from 

seal oil degassing vents, pump and compressor seal leakage, relief valve leakage, and relief 

valve discharges because of over-pressure operation. A closed-vent system consists of 

piping connectors, flame arrestors, and, if necessary, flow-inducing devices. Closed-vent 

systems are designed and operated so that all emissions are transported to a control device 

without leakage to the atmosphere. 

Several types of control devices can be used to dispose of VOC and HAP 

emissions captured in the closed-vent system. Incineration, carbon adsorption, and 

condensation are three control methods that typically are applied. 

1.2.3 Leak Minimization Standards 

Equipment leak standards are designed to control emission leaks from regulated 

equipment through the application of work practices, equipment standards, and 

operational practices. The work practice most commonly applied to control equipment 

leaks is the LDAR program. Equipment practices include the use of specific types of 

components, equipment design standards or specifications, and operational standards for 

certain types of equipment. Equipment practices are evaluated using performance 

standards that provide a basis for monitoring or substantiating the effectiveness of such 

control practices. 

1.2.3.1 Leak Detection and Repair 

LDAR programs consist of two phases: (1) monitoring potential fugitive emission 

sources within a process unit to detect leaks, and (2) repair or replacement of the leaking 

component. 

The level of emission reduction achieved by a LDAR program is affected by 

several factors. The three main factors are monitoring interval, leak definition, and repair 

interval: 

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• Monitoring interval--The monitoring interval is the frequency at which 

individual component monitoring is conducted. For example, valves are 

generally required to be monitored once a month using a leak detection 

instrument, but the monitoring interval may be extended to once every 

quarter for each valve that has not leaked for two successive months. The 

LDAR programs also specify weekly visual inspections of pumps and 

compressors for indications of liquids dripping from the seals. 

• Leak definition--The leak definition is the VOC (or HAP) concentration 

observed during monitoring with a leak detection instrument that exceeds 

the threshold standard for the applicable regulation. Leaks may also be 

defined on the basis of visual inspections. In other cases, monitoring is 

required if certain indications of leaks are observed. 

• Repair interval--The repair interval is defined as the length of time allowed 

between detection of a leak and repair of the leak. When a leak is detected, 

the affected component is required to be repaired as soon as practicable, 

but not later than 15 calendar days after the leak is detected, unless the 

conditions described under "Delay of Repair" (later in this section) are met. 

For each component, the first attempt at repair is to be made no later than five 

calendar days after each leak is detected. First attempts at repair include, but are not 

limited to, the following best practices, where practicable and appropriate: 

• Tightening of bonnet bolts 

• Replacement of bonnet bolts 

• Tightening of packing gland nuts 

• Injection of lubricant into lubricated packing 

Other factors that can improve the efficiency of an LDAR program that are not 

addressed by the standards include training programs for equipment monitoring personnel 

and tracking systems that address the cost efficiency of alternative equipment (e.g., 

competing brands of valves in a specific application). 

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1.2.3.2 Equipment, Design, Operational, and Performance Standards 

Equipment standards refer to the use of specific types of components. Design 

standards include requirements for dual mechanical seals, closed purge and vent systems, 

caps, blind flanges, second valves, and control equipment specifications associated with 

flares and enclosed combustion devices. 

Certain equipment operations, e.g., the proper sequence for closing double blocks 

and bleed valves or the requirement to maintain a pilot flame in flares, are regulated 

through implementing operational standards. 

Performance standards refer to no detectable emissions and percent reduction 

efficiency for control devices. Annual monitoring is used for components subject to the 

"no detectable emissions" requirement, which requires emissions of less than 500 ppmv 

above background levels. No detectable emissions components include pumps, 

compressors, valves (specifically designated for no detectable emissions), pressure relief 

devices in gas/vapor service, and closed-vent systems for both NSPSs and NESHAPs. 

1.2.4 Federal Equipment Leak Regulations 

Federal equipment leak regulations affecting chemical manufacturing facilities 

consist of standards promulgated under the NSPS, NESHAP, and the Resource 

Conservation and Recovery Act (RCRA). NSPSs are implemented under Section 111 of 

the Clean Air Act and apply to newly constructed stationary sources--those sources 

constructed after the date that an NSPS is proposed in the Federal Register. NSPSs 

become effective upon promulgation. In addition, existing stationary sources (sources 

existing prior to the NSPS proposal date) can become subject to an NSPS if they are 

modified or reconstructed after the NSPS proposal date. A degree of national uniformity 

to air pollution standards is established through NSPSs. Such uniformity tends to 

preclude situations in which certain States could attract new industries as a result of 

relaxed standards, relative to other States. 

NESHAPs, which are implemented under Section 112 of the Clean Air Act, apply 

to both new and existing stationary sources. NESHAPs are intended to control hazardous 

pollutants such as carcinogens or other serious disease-causing agents. Formerly, they 

were developed and implemented for individual pollutants, but this proved to be an 

extremely cumbersome and slow-moving process. By 1990, NESHAPs had been 

established for only eight pollutants. Of these, equipment leak regulations were applied 

only to benzene and vinyl chloride. The Clean Air Act Amendments of 1990 (CAAA) 

have changed the approach for controlling hazardous air pollutants. In the CAAA, 189 

chemicals are identified as air toxics that will be controlled on a source category basis. A 

subset of the listed chemicals will be regulated under the HON. 

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As a class, organic air emissions at hazardous waste treatment, storage, and 

disposal facilities (TSDFs) are regulated under Subtitle C of RCRA. Final standards are 

established in the rule to limit leaks from equipment (e.g., pumps and valves) that contains 

or contacts hazardous waste streams with 10 percent or more total organics. The final 

standards incorporate, or closely follow, many of the provisions of the equipment leak 

NSPS and the benzene NESHAP. These standards are promulgated under authority of 

Section 3004 of the Hazardous and Solid Waste Amendments to RCRA and are 

incorporated into Parts 264 and 265 (Subpart BB), Air Emission Standards for Owners 

and Operators of Hazardous Waste Treatment, Storage, and Disposal Facilities (U.S. 

EPA, 1990b). 

1.2.4.1 Federally Regulated Source Categories - NSPS 

The NSPS equipment leak standards for the SOCMI are in Subpart VV of 40 CFR 

Part 60, and sections (§) of this standard are found in §60.480 through §60.489. The 

proposal and applicability date for Subpart VV is January 5, 1981. The rule was 

promulgated on October 18, 1983. 

1.2.4.2 Sources Subject to NESHAP Regulations 

NESHAPs have been established for equipment leaks of two designated VHAPs-­

benzene and vinyl chloride. Only the benzene NESHAP is applicable to chemical 

manufacturing facilities. 

The NESHAPs are found in 40 CFR Part 61. Part 61 contains the national 

emission standards for hazardous air pollutants, including the following subparts: 

• Subpart J specifies the national emission standard for equipment leaks of 

benzene and basically incorporates Subpart V as its standards. Subpart J is 

found in §61.110 through §61.112. Subpart J was promulgated on June 6, 

1984. 

• Subpart V contains the national emission standard for VHAP equipment 

leaks. This subpart contains generic provisions and standards that are 

incorporated by reference in 40 CFR 61, Subpart J. Subpart V is found in 

§61.240 through §61.247. Subpart V was promulgated on June 6, 1984. 

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1.2.4.3 Hazardous Organic National Emission Standard (HON) 

The HON for equipment leaks at organic chemical plants is found at 40 CFR Part 

63, Subpart H, in §63.160 through §63.182. These standards apply to equipment in 

organic hazardous air pollutant service for 300 or more hours per year. The chemical 

manufacturing processes and organic HAPs subject to the rule are published in Tables 1 

and 2 of Subpart F to 40 CFR Part 63 (see Volume II, Appendices F and G). 

Subpart H standards also apply to some additional processes that produce certain 

butadienes, chlorine, or styrene-based products. These processes are addressed in Subpart 

I of 40 CFR 63 (see Volume II, Appendix H) at §63.190 through §63.193. The HON was 

promulgated on April 22, 1994. 

A number of the manufacturing processes listed under the HON also contain 

equipment subject to NSPS or NESHAP equipment leak standards. Wherever such 

overlapping rules apply, the HON takes precedence. 

1.2.4.4 Hazardous Waste Facility Emission Standards 

Organic air emissions at hazardous waste TSDFs are found at Parts 264 and 265 

(Subpart BB), Air Emission Standards for Owners and Operators of Hazardous Waste 

Treatment, Storage, and Disposal Facilities and Air Emissions Standards for Owners and 

Operators of Interim Status Hazardous Waste Treatment, Storage and Disposal Facilities, 

respectively. The regulations may be found at §264.1050 through §264.1065 and 

§265.1050 through §265.1064. The rules were both promulgated on June 21, 1990. 

1.3 APPROACHES TO RULE ENFORCEMENT 

Reports, recordkeeping requirements, and inspections form the basis of assessing 

compliance with the Federal equipment leak standards. Inspections require the evaluation 

of records and reports as well as the performance of on-site inspections, including leak 

detection. Both activities are necessary to the accomplishment of effective regulatory 

oversight. 

1.3.1 Review of Reports and Recordkeeping 

The review of records and reports can encompass two separate functions: (1) 

determination that the records and reports are in compliance with the applicable standards, 

and (2) use of records and reports in the performance of on-site inspections. One of the 

goals of this manual is to assist inspectors in evaluating the often complicated and 

voluminous records that are an essential part of the equipment leak programs. The 

records and reports required by the Federal equipment leak standards are essential 

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elements for the demonstration of compliance by the regulated facility. It should be noted 

that these regulations are complicated and are not uniform from one category to another. 

It is imperative therefore, that the inspector be thoroughly knowledgeable of the source 

specific regulations before conducting an inspection. This will aid the inspector in 

recognizing what types of information are important for the compliance determination as 

well as providing a means of preparation for site visits and inspections. 

1.3.2 On-Site Inspections 

On-site inspections can encompass the direct monitoring of regulated equipment 

and measurement of equipment leaks as well as observational techniques addressing plant 

procedures, equipment usage, and evaluation of monitoring and testing performed by the 

plant. One goal of this manual is to provide guidance in the development and 

implementation of direct monitoring inspections. Another goal is to enable the inspector, 

through observational techniques, to determine if plant personnel are in full compliance 

with EPA Method 21 field monitoring techniques and if they are adequately identifying 

regulated and/or leaking equipment. Inspectors must, therefore, be thoroughly familiar 

with VOC detector operating principles, calibration procedures, operating problems, and 

leak screening techniques in order to perform both types of inspections. 

1.4 ORGANIZATION OF DOCUMENT 

Chapter 2 - Applicability 

The focus of this chapter is to address applicability determinations needed to 

ensure the correct rule(s) is (are) being complied with, all appropriate components are 

included in the program, and all such components are correctly identified as to which 

service they are in. 

Chapter 3 - Compliance/Inspection Through Reports and Recordkeeping 

This chapter addresses the review of reports and recordkeeping for compliance 

with the Federal equipment leak regulations. 

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Chapter 4 - Compliance/Inspection Through Walk-Through Monitoring 

This chapter addresses the compliance and inspection issues that can be addressed 

by conducting an actual walk-through of the facility including on-site review of records 

and the use of a monitor during the walk-through. 

Chapter 5 - Recommended Inspection Techniques and Procedures 

This chapter provides a summary of the pros and cons of both enforcement 

strategies. Actual programs should seek a balance between the two. The best procedure 

will vary based on resources available to the inspector and the air quality priorities of the 

regions. 

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CHAPTER 2 

APPLICABILITY 

This chapter addresses three critical applicability determinations. The first 

determination is to ensure the correct rules are being complied with at any given facility. 

Second, once the correct rule is determined for each process area within a facility, 

determine whether all appropriate components have been identified. The third critical 

determination is to ensure that these components are properly classified as to what type of 

service they are in. 

These three determinations are discussed in the following sections of this chapter. 

For each determination, a discussion of each regulation is presented, followed by a 

discussion of procedures that can be used in making these critical determinations. 

2.1 WHICH REGULATION? 

2.1.1 Specific Regulations 

At many chemical manufacturing facilities, more than one Federal equipment leak 

rule may be applicable to different pieces of equipment or process areas within the facility. 

However, each rule has a precedence ranking relative to the other rules such that only one 

rule should be applicable to any specific piece of equipment or process area. 

The HON standard (40 CFR 63, Subpart H and I) is the best place to begin for the 

determination of rule precedence. The rule takes precedence over any equipment also 

subject to NSPS or NESHAP standards, including some equipment previously subject to 

benzene regulations. If a process is not subject to 40 CFR 63, it should be reviewed for 

benzene applicability (40 CFR 61, Subparts J and V). The NESHAPs take precedence 

over any applicable NSPS [§61.110(d) or §61.240(c)]. 

Several terms important to determination of rule applicability can be confusing 

because they have different meanings under some of the rules (e.g., affected facility) or 

can be used in different contexts (in service). Those terms important to the following 

discussions are reviewed here to help clarify how the standards are applied. 

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Affected Facility. An affected facility is an emission source or group of emission 

sources to which a standard applies. Part 60, Subpart VV defines affected facility as the 

“group of all equipment within a process unit." All of the other rules addressed by this 

manual define each individual piece of equipment (e.g., pump, compressor) as the affected 

facility. 

Process Unit. All of the standards (except RCRA Subpart BB) contain the 

following generic definition: "a process unit can operate independently if supplied with 

sufficient storage facilities for the product." Each standard also contains specific qualifiers 

(see Table 2.1). The RCRA definition of a hazardous waste management unit refers to the 

area in which a hazardous waste is stored or in which constituent wastes are mixed. 

Table 2.1. Process Unit Definitions--Specific Qualifiers 

Standard Specific Process Unit Definition 

40 CFR Part 60 Components assembled to produce, as intermediate or final products, one or more 

of the chemicals listed in §60.489 of Subpart VV. 

40 CFR Part 61 Equipment assembled to produce VHAP or its derivatives as intermediates or 

final products, or equipment assembled to use a VHAP in the production of a 

product. 

40 CFR Part 63 Equipment assembled and connected by pipes or ducts to process raw materials 

and to manufacture an intended product. 

40 CFR Part 265 A contiguous area of land on or in which hazardous waste is placed, or the largest 

area in which there is significant likelihood of mixing hazardous waste 

constituents in the same area. Example: A tank and its associated piping and 

underlying containment system. 

The EPA clarifies the definition of process unit for the SOCMI standards, as 

follows: The definition was drafted by EPA to provide a practical way to determine which 

equipment is included in an affected facility. There are no specific physical boundaries or 

size criteria. The definition instead depends upon several operational factors, including 

chemical produced and the configuration of the processing equipment. Such 

configurations may be different for different producers of the same chemical; therefore, the 

definition may be fairly site specific. In practice, however, the definition will implement 

the selection of a process unit basis as the "source" covered by the standards. 

Service. Service refers to two district concepts. "In . . . service" addresses the 

specific conditions by which rule applicability is determined. These terms (in organic HAP 

service, in volatile organic compound (VOC) service, etc.) are discussed in this section. 

"Type of service" refers to the physical condition of the process material: gas/vapor, light 

liquid, or heavy liquid. Type of service is discussed in a later section of this chapter. 

2.1.1.1 40 CFR Part 63 

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Within the chemical industry, the HON applies to major sources which 

manufacture as a primary product one or more of a designated list of chemicals and which 

make or use as a reactant or manufacture as a product, co-product, or byproduct any of a 

designated list of organic HAPs. The applicable chemicals and HAPs are published as 

Table 1 and Table 2 of 40 CFR 63, Subpart F. 

In addition to the chemical manufacturing processes referred to above, the HON 

also applies to a number of processes that produce certain butadiene-, chlorine-, or 

styrene-based products. These processes are identified in 40 CFR 63, Subpart I, and are 

required to comply with the provisions of Subpart H. 

For those facilities subject to the HON, the standards apply to equipment in 

organic hazardous air pollutant service for 300 or more hours per year. "In organic HAP 

service" means that the equipment contains or contacts a fluid that is five percent or 

greater by weight of total organic HAP. Within the rule, specific standards apply to 

equipment in different types of service: gas/vapor, light liquid, and heavy liquid. 

The HON also stipulates that each piece of equipment within a process unit that 

can reasonably be expected to contain equipment in organic HAP service is presumed to 

be in organic HAP service unless an owner or operator demonstrates that the piece of 

equipment is not in organic HAP service. For a piece of equipment to be considered not 

in organic HAP service, it must be determined that the percent organic HAP content can 

be reasonably expected not to exceed five percent by weight on an annual average basis. 

For purposes of determining the percent organic HAP content of the process fluid that is 

contained in or contacts equipment, Method 18 of 40 CFR Part 60, Appendix A is to be 

used. 

The HON is applicable to both new and existing facilities, regardless of their date 

of construction. For the purpose of establishing compliance deadlines, those processes 

subject to Subpart H are divided into five distinct groups. The compliance dates (as of 

April 10, 1995) for the process groups at existing sources are as follows: 

Group I: October 24, 1994 

Group II: January 23, 1995 

Group III: April 24, 1995 

Group IV: July 24, 1995 

Group V: October 23, 1995 

The group designation for each process unit is indicated in Table 1 of Subpart F. 

However, the owner/operator of a plant has the option to comply at an earlier date than 

required by the schedule. 

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New sources that commence construction or reconstruction after December 31, 

1992, should be in compliance with Subpart H upon initial startup or April 22, 1994, 

whichever is later. 

Existing sources identified in Subpart I were required to comply with the standard 

no later than October 24, 1994. New sources are required to comply upon initial start-up. 

Finally, any equipment that is in vacuum service and equipment that is in organic 

HAP service less than 300 hours per year are excluded from the requirements of the HON 

standard. No other specific exemptions are identified in the rule. Equipment in VHAP 

service less than 300 hours per year as well as exempt equipment in vacuum service must 

be identified in plant records. 

2.1.1.2 40 CFR Part 61 

The benzene equipment leak standards apply to components that are intended to 

operate in benzene service. This is defined as "a piece of equipment which either contains 

or contacts a fluid (liquid or gas) that is at least 10 percent benzene by weight." Generic 

provisions and standards for equipment in VHAP service are at 40 CFR 61 Subpart V, and 

the benzene standards are at 40 CFR 61 Subpart J. 

As with the HON, the benzene equipment leak standards apply to both new and 

existing sources, and no applicability date separates new from existing sources. Each 

piece of equipment within a process unit that can conceivably contain equipment in VHAP 

service is presumed to be VHAP service unless an owner or operator demonstrates that 

the piece of equipment is not in VHAP service. A piece of equipment is considered to be 

not in VHAP service if the percent VHAP content can be reasonably expected never to 

exceed 10 percent by weight. Such determinations can be made through the use of 

engineering judgement or by following procedures that conform to ASTM Method D2267. 

These standards do not apply to sources located in coke by-product plants. Any 

equipment in benzene service located at a plant site designed to produce or use less than 

1,000 mg of benzene per year is exempt from the benzene NESHAP. This cutoff is 

intended to exempt most research and development facilities and other small-scale 

operations. Also exempt is any process unit that has no equipment in benzene service and 

any equipment that is in vacuum service. All exempt equipment and equipment not in 

VHAP service must be identified in plant records. 

2.1.1.3 40 CFR Part 60 

SOCMI is a broad source category that covers plants that produce many types of 

organic chemicals. Examples of organic chemicals produced in the SOCMI segment 

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include acetone, methyl methacrylate, toluene, and glycine. The complete list of organic 

chemicals covered by SOCMI equipment leak standards is found in §60.489 of 40 CFR 

Part 60. 40 CFR 60 Subpart VV applies to the industries that produce as intermediates, 

byproducts, or final products, one or more of the chemicals listed in §60.489 of the 

standard. The standards apply to any affected facility that commenced construction or 

modification after January 5, 1981. 

Subpart VV applies to any piece of equipment which contains or contacts a 

process fluid that is at least 10 percent VOC by weight. 

Any affected facility that has the design capacity to produce less than 1,000 

megagrams (Mg) (1,100 tons) per year is exempt from the SOCMI rules. An affected 

facility that produces heavy liquid chemicals only from heavy liquid feed or raw materials 

is also exempt. Exemptions also apply to: any affected facility that produces beverage 

alcohol, any affected facility that has no equipment in VOC service, and all equipment in 

vacuum service. 

2.1.1.4 40 CFR Part 264 and 265 

40 CFR Part 264, Subpart BB applies to owners and operators of facilities that 

treat, store, or dispose of hazardous wastes (TSDFs). Part 265, Subpart BB applies to 

owners and operators of interim status TSDFs. These subparts apply to equipment that 

contains or contacts hazardous wastes with organic concentrations of at least 10 per cent 

by weight that are managed in: (1) units that are subject to the permitting requirements of 

40 CFR Part 270, or (2) hazardous waste recycling units that are located on hazardous 

waste management facilities otherwise subject to the permitting requirements of Part 270. 

A facility may be an operational chemical manufacturer, but any organic waste streams it 

generates may render it subject to 264/265 BB (i.e., it does not need to be a commercial 

treatment, storage, or disposal facility). 

Any equipment that is in vacuum service is excluded from the requirements of this 

standard. However, equipment in vacuum service must be identified in plant records. 

These regulations do not affect conditionally-exempt or small-quantity generators, and 

they do not affect satellite accumulation areas. 

2.1.2 Procedures to Determine if Appropriate Rule is Being Applied 

Determination of rule applicability is ultimately the responsibility of the regulated 

facility. Normally, any questions regarding applicability are reviewed and resolved 

through the State permitting process. Thus, an inspector can determine which rules are 

being applied to a facility by consulting that facility's air permits. However, permits are 

not always correct, and total reliance on the permit is not recommended. A thorough 

knowledge and understanding of the various process areas within a facility, and the 

2-5
relationship of such processes to potentially applicable rules, will contribute to an 

inspector's effectiveness. 

At any given facility, there will be an ongoing activity of equipment replacement or 

retirement and additions or modifications to the various processes. Good process 

knowledge will help the inspector to keep track of such changes, understand how the 

current rule applies to new equipment, and identify any oversights by the facility in the 

identification of such equipment. Additionally, the inspector may identify situations such 

as changes to process constituents or formula, or major modifications, which necessitate a 

review of rule applicability. With experience, the inspector may be able to identify entire 

processes or facilities which an owner/operator has failed to recognize as potentially 

subject to a rule. 

2.2 WHICH COMPONENTS? 

2.2.1 Specific Components 

Each of the Federal equipment leak regulations specifies a list of components 

covered by each regulation. Specific components common to all of the regulations 

include: valves, connectors, pumps, compressors, pressure relief devices, sampling 

connection systems, open-ended valves or lines, and closed vent systems and control 

devices. The benzene NESHAP also applies to product accumulator vessels, whereas the 

HON also applies to agitators, surge control vessels, bottoms receivers, and 

instrumentation systems. 

2.2.2 Guidance to Determine if Equipment Has Been Identified Properly 

Production facilities subject to one or more of the equipment leak standards are 

typically large plants with a very large number of components. In order to comply with 

the various standards, an owner or operator needs to be able to locate and identify those 

components subject to the standards and to reference any relevant information applicable 

to each individual component. Some types of information are required by some of the 

rules; other information is simply useful or prudent from the owner/operator's perspective. 

An inspector should develop a detailed understanding of a facility's component 

identification system, as well as information about the components themselves. 

2-6
The most basic element of any component identification system is the assignment 

of a unique identification (ID) number to each component. The ID number is used to 

comply with various recordkeeping and reporting requirements. For example, the ID 

number of each component that is found to be leaking is recorded in a log. In addition, a 

list of the ID numbers of all equipment subject to the standards are to be recorded in a log. 

Lists of identification numbers are also required for equipment in vacuum service, and 

other equipment in any special status identified by the regulations. 

Following establishment of an ID system, being able to establish the exact location 

of each component is the next basic element. Most ID systems are designed to facilitate 

location by incorporating the individual process unit (or other geographically convenient 

criteria) into the number system. For the NSPS equipment leak standards, components 

are only subject to the standards if they are located in an affected facility. Therefore, it is 

important to identify the location of each component with regard to the process unit it is in 

and whether that process unit is an affected facility. 

Another item of concern to the inspector is the relationship between the plant's 

inventory of equipment subject to the standards and the equipment which is actually in 

service. When individual pieces of equipment or subsections of a process area are taken 

out of service, such equipment should be routinely retired or identified as out-of-service 

on the inventory. Likewise, new or replacement equipment should be added to the 

inventory. If an inspector can identify equipment that has not been properly added or 

deleted from the inventory, then the facility may not be in full compliance with the 

applicable rule. 

2.3 WHICH SERVICE? 

2.3.1 Service Definition 

The specific standards applied to equipment subject to these rules depends on the 

type of service the equipment is in. Most rules identify three types of conditions: 

gas/vapor service, light liquid service, and heavy liquid service. Part 61 does not define 

"light" or "heavy" liquid, just "liquid service." Definitions of the three types of service are 

the same, although several rules provide for alternative means of measurement or 

demonstration. 

"In gas/vapor service" means that the piece of equipment contains or contacts 

process fluid that is in the gaseous state at operating conditions. All of the standards use 

this definition except the HON, which refers to "equipment in organic hazardous air 

pollutant service (which) contains a gas or vapor at operating conditions.” 

Equipment is "in light liquid service" if all of the following conditions are met: 

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• The vapor pressure of one or more components is >0.3 kPa (0.04 psi) at 

20oC. 

• The total concentration of the pure components, with a vapor pressure 

>0.3 kPa (0.04 psi) at 20oC, is $20 percent by weight. 

• The fluid is a liquid at operating conditions. 

40 CFR Part 61, Subpart V defines "in liquid service" rather than differentiating 

between "in light liquid service" and "in heavy liquid service." In liquid service means that 

a piece of equipment is not in gas/vapor service. The HON also uses this definition of "in 

liquid service." 

A summary of components and type of service designations covered by the Federal 

equipment leak regulations is presented in Table 2.2. 

2.3.2 Guidance to Determine if Correct Service is Identified 

As is the case with rule applicability, determination of type of service is the 

responsibility of the regulated facility. The regulations require that documentation of type 

of service determination be maintained by the facility. If an inspector questions a facility's 

classification, a review of the records which address how the type of service classification 

was made would be the first step. 

An inspector may also be able to review process and material balance data to 

determine if type of service classifications are appropriate. As a final course of action, an 

inspection may collect a sample of the process material in question and apply the analysis 

specified by the applicable rule. 

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TABLE 2.2

SUMMARY OF EQUIPMENT LEAK COMPONENTS COVERED

COMPONENT 40 CFR Part 60, 

Subpart VV 

40 CFR Part 61, 

Subparts J and V 

40 CFR Part 63, 

Subparts H and I 

40 CFR Part 264, Subpart BB 

40 CFR Part 265, Subpart BB 

Valves, gas/vapor 

service 60.482-7 

in VHAP service 

61.242-7 

63.168 264.1057 

265.1057 

Valves, light liquid 

service 60.482-7 63.168 264.1057 

265.1057 

Valves, heavy 

liquid service 60.482-8 63.169 264.1058 265.1058 

Pumps, light liquid 

service 60.482-2 

in VHAP service 

61.242-2 

63.163 264.1052 

265.1052 

Pumps, heavy 

liquid service 60.482-8 63.169 264.1058 265.1058 

Pressure relief 

devices, gas/vapor 

service 

60.482-4 61.242-4 63.165 

264.1054 

265.1054 

Pressure relief 

devices, light liquid 

service 

60.482-8 

in liquid service 

61.242-8 

in liquid service 

63.169 

264.1058 

265.1058 

Pressure relief 

devices, heavy 

liquid service 

60.482-8 264.1058 

265.1058 

Compressors 60.482-3 61.242-3 63.164 264.1058 

265.1053 

Sampling 

connection systems 60.482-5 61.242-5 63.166 264.1055 265.1055 

Open-ended valves 

or lines 60.482-6 61.242-6 63.167 264.1056 265.1056 

Flanges and other 

connectors (all 

services) 

60.482-8 61.242-8 NA 264.1058 

265.1058 

Connectors in 

gas/vapor service NA NA 63.174 NA 

Connectors in light 

liquid service NA NA 63.174 NA 

Connectors in 

heavy liquid service NA NA 63.169 NA 

Closed-vent 

systems and 

devices 

60.482-10 61.242-11 63.172 264.1060 

265.1060 

Agitators in 

gas/vapor service NA NA 63.173 NA 

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TABLE 2.2

SUMMARY OF EQUIPMENT LEAK COMPONENTS COVERED

COMPONENT 40 CFR Part 60, 

Subpart VV 

40 CFR Part 61, 

Subparts J and V 

40 CFR Part 63, 

Subparts H and I 

40 CFR Part 264, Subpart BB 

40 CFR Part 265, Subpart BB 

Agitators in light 

liquid service NA NA 63.173 NA 

Agitators in heavy 

liquid service NA NA 63.169 NA 

Instrumentation 

systems 

NA NA 63.169 NA 

Product 

accumulator vessels NA 61.242-9 NA NA 

Surge control 

vessels NA NA 63.170 NA 

Bottoms receivers NA NA 63.170 NA 

NA - not applicable 

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CHAPTER 3 

COMPLIANCE/INSPECTION THROUGH 

REPORTS AND RECORDKEEPING 

It is extremely important that an inspector be thoroughly familiar with the 

reporting and recordkeeping requirements of the regulations. With the exception of 

RCRA, all of the equipment leak standards addressed by this manual stipulate that 

compliance with the applicable standards will be determined by review of required records, 

by review of performance test results, and by inspections. The NSPS and HON also 

reference reports as a basis for compliance demonstration. Parts 264 and 265 both specify 

recordkeeping requirements, and Part 264 requires reports if leak repairs are not 

completed on schedule or if control devices deviate from their operational standards for 

more than 24 hours. Review of reports and records is also a critical component in the 

conduct of effective on-site inspections. 

This chapter first addresses the content of required reports for the NSPS, 

NESHAP and HON and discusses their review for the purposes of compliance 

determination. Recordkeeping requirements of the NSPS, NESHAP, HON, and RCRA 

regulations are then addressed, with a concluding discussion of recordkeeping compliance 

reviews. The chapter concludes with additional discussion of strategies an inspector can 

use to supplement the review of records and reports. Chapter 4 addresses the role of 

records and reports as a resource for on-site inspections. 

3.1 REPORTS 

3.1.1 40 CFR Part 60, Subpart VV 

Facilities subject to Subpart VV are required to submit reports both under the 

general provisions, which are applicable to all NSPSs unless the specific subpart says 

otherwise, and under Subpart VV. The following paragraphs identify the various reports 

required and the information each is to contain. Failure to submit the required reports on 

time and with the required information may be grounds for non-compliance. 

The NSPS General Provisions (40 CFR Part 60, Subpart A, §60.7) mandate that 

any owner or operator subject to a NSPS must provide written notification of the date of 

3-1
construction or reconstruction within 30 days after work begins. In addition to the 

construction or reconstruction notification, the general provisions require the following: 

• A notification of the anticipated date of initial startup of an affected facility 

postmarked between 30 and 60 days before the startup date. 

• A notification of the actual date of initial startup of an effective facility 

within 15 days after startup. 

• A notification of any physical or operational change to an existing facility 

that may increase the emission rate of any pollutant to which a standard 

applies, unless that change is specifically exempted. This notice shall be 

postmarked 60 days, or as soon as practicable, before the change. 

3.1.1.1 Initial Reports 

Under Subpart VV facilities are required to submit semiannual reports beginning 

six months after the initial startup date and every six months thereafter. The initial report 

must include an identification of the process unit, the number of valves in gas/vapor 

service or light liquid service, the number of pumps in light liquid service, and the number 

of compressors. Valves, pumps, and compressors that are designated as having no 

detectable emissions should not be included in the totals listed in the initial report. 

3.1.1.2 Semiannual Reports 

Semiannual reports are required beginning six months after the initial report and 

each six months thereafter. These reports contain information on the results of LDAR 

programs. The information required in these reports begins with the process unit 

identification, which should correspond with the identification in the initial report. The 

semiannual report must document, on a monthly basis, the total number of detected leaks 

and the number of this total that were not repaired in the required 15-day period. In each 

instance where a repair is delayed, the report is to explain the delay. If the reason for the 

delay is that it could not be repaired until a process unit shutdown, then the report is to 

indicate why a process unit shutdown was technically infeasible during the reporting 

period. The report shall then show the dates during the reporting period when process 

unit shutdowns occurred. In addition, any revisions to items reported in the initial report 

are to be described and discussed. The format of reports is not specified in the 

regulations, and a number of variations are acceptable. 

3-2
3.1.1.3 Other Reporting Requirements 

Other reporting requirements contained in the NSPS regulations include two 

alternative standards for valves: the allowable percentage of valves leaking, and the skipperiod LDAR program. If an owner or operator elects to comply with either of these 

alternative standards, a notification must be provided 90 days before implementing the 

provisions. 

40 CFR Part 60 also requires the owner or operator to submit a written report of 

the results of any performance test to EPA. Performance tests are required for no 

detectable emissions equipment and valves complying with an alternative standard. They 

also may be required for closed-vent systems, control devices, and equivalent means of 

emission limitation. Information must be made available to EPA as necessary to determine 

the operating conditions during the performance tests. In addition, Subpart VV requires 

that the owner or operator notify the Administrator of the schedule for the initial 

performance tests at least 30 days before conducting them. 

3.1.2 40 CFR Part 61 

40 CFR Part 61, Subparts J and V require submission of an initial statement and 

semiannual reports. 

3.1.2.1 Initial Reports 

The initial report must contain two portions: a written assertion stating that the 

company will implement the standards and the testing, recordkeeping, and reporting 

requirements contained in the applicable NESHAP; and information on the equipment 

subject to the regulation, including equipment identification (ID) numbers, process unit 

IDs for each source, and a description of the type of equipment (e.g., a pump or a pipeline 

valve). Also, the percent by weight of VHAPs in the fluid being handled by the equipment 

and the state of the fluid (i.e., gas/vapor or liquid) must be included. Finally, the initial 

report must contain a description of the chosen method of compliance and a schedule for 

subsequent semiannual reports. The source must abide by this schedule unless it is 

amended in subsequent semiannual reports. 

All facilities in existence on the effective date of any NESHAP were required to 

submit an initial report. Therefore, all existing facilities subject to the above-referenced 

standards should have already submitted an initial report. All new plants are required to 

submit an initial report with the application for approval of construction, as required by 

the general provisions of Part 61 (NESHAP). 

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3.1.2.2 Semiannual Reports 

Six months after the initial report, and every six months thereafter, the facility must 

submit a semiannual report. These semiannual reports are for NESHAP compliance and 

are similar to the required NSPS semiannual reports. They must provide process unit IDs 

for regulated equipment and, on a monthly basis for each process unit, the number of 

valves, compressors, and pumps that were detected leaking. Of those valves, 

compressors, and pumps that were detected leaking, the number that were not repaired 

within 15 days is to be reported, along with an explanation of why a repair was delayed. If 

the reason for the delay was that a process unit shutdown is needed before repair, then an 

explanation must be given why a process unit shutdown was infeasible. 

The report also must include the dates of all process unit shutdowns during the sixmonth reporting period and a discussion of any revisions to the initial report or subsequent 

revisions to the initial report. The regulations do not specify the format of the reports; 

they only specify minimum content requirements. Each facility develops and uses its own 

format. 

These standards allow the designation of equipment subject to a no detectable 

emissions limit rather than an LDAR standard, an alternative standard based on the 

allowable percentage of valves leaking, and an alternative skip-period LDAR program. 

All three of these as well as closed-vent systems and control devices require performance 

tests. If a performance test was conducted within the six-month reporting period, then the 

results of the test also must be included in the semiannual report. 

3.1.2.3 Other Reporting Requirements 

An owner or operator of a facility electing to comply with either of the alternative 

standards for valves (i.e., the allowable percentage of valves leaking or the skip-period 

LDAR program), must provide notification 90 days before implementation of either of 

these programs. 

Certain circumstances described in the regulations do not require an application for 

approval of construction/modification. These circumstances are: (1) a new source 

complies with the standards, (2) a new source is not part of the construction of a process 

unit, or (3) all information required in the initial report is contained in the next semiannual 

report. 

3.1.3 40 CFR Part 63, Subparts H and I 

Existing facilities subject to the HON standards are required to submit an initial 

notification that describes the source and the chemical manufacturing processes subject to 

the standards. New sources (if the start-up date is 90 days or more after the promulgation 

3-4
date) are required to submit an application for approval of construction or reconstruction 

in lieu of the initial notification. All sources are required to submit a Notification of 

Compliance Status within 90 days of the applicable compliance date. This notification 

describes how the source will maintain compliance with the standard. Finally, periodic 

reports are to be submitted semiannually beginning six months after the Notification of 

Compliance Status. Reports can be submitted on electronic media where acceptable to the 

regulating agency and the owner/operator of the source. 

3.1.3.1 Initial Notification 

The initial notification required of existing sources is due within 120 days of the 

date of promulgation of the applicable standard (April 22, 1994, for Subparts H and I). It 

is to include the name and address of the owner or operator, the address (physical 

location) of the affected source, identification of the chemical manufacturing processes 

subject to the subpart, and a statement of whether the source can achieve compliance by 

the applicable compliance date. The application for approval of construction or 

reconstruction submitted by new sources is to contain the same information as required for 

the initial notification. 

3.1.3.2 Notification of Compliance Status 

The Notification of Compliance Status is due within 90 days of the applicable 

compliance date (Subpart H has five dates, see Chapter 1) for existing sources. New 

sources, which are required to comply with Phase II of the HON upon initial startup, 

would include the equivalent compliance status information in their application. The 

Notification of Compliance Status requires the following information for each process unit 

subject to the standards: 

• Process unit identification 

• Number of each equipment type (e.g., valves, pumps) excluding equipment 

in vacuum service 

• Method of compliance with the standard (e.g., "monthly LDAR" or 

"equipped with dual mechanical seals") 

• A planned schedule for each phase of the requirements applicable to pumps 

in light liquid service and valves in gas/vapor or light liquid service. 

If a source elects to use pressure testing of batch product process equipment to 

demonstrate compliance, the notification report is to include the batch products or product 

codes subject to this option and the planned schedule for pressure testing of the equipment 

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when it is configured for such production. The notification shall identify each enclosedvented process unit and describe the negative pressure system and control device used. 

3.1.3.3 Periodic Report 

The periodic reports are to be submitted semiannually and are to convey the 

following information for each process unit for each monitoring period during the sixmonth period reported: 

• The number (by type) of valves, pumps, compressors, agitators, 

connectors, and screwed connectors that were detected leaking and the 

number for which leaks were not repaired as required in the standard. 

• The total number (by type) of valves, pumps, connectors, and screwed 

connectors monitored and the percent of the total found leaking. 

• The number of unrepaired valves and the number of unrepaired connectors 

that are determined non-reparable. 

• The facts that explain any delay of repairs and, where appropriate, why a 

process unit shutdown was technically infeasible. 

• The results of all monitoring of pressure relief devices, closed-vent 

systems, and any compressors designated to operate at less than 500 ppm. 

• If applicable, implementation of a monthly monitoring program for valves, 

a quality improvement program for valves or pumps, or a change in 

connector monitoring alternatives. 

If the source has elected to use pressure testing to demonstrate compliance for 

batch process equipment, the report shall also include: 

• Batch product process equipment train identification. 

• The number of pressure tests conducted and the number of tests where the 

equipment train failed the test. 

• The facts that explain any delay of repairs. 

• The results of all monitoring to determine compliance with standards for 

closed-vent systems and control devices. 

3.1.4 40 CFR Parts 264 and 265, Subpart BB 

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TSDF facilities to which Part 264 applies are not required to submit an initial 

report and are required to submit a semiannual report only under certain conditions. 

These conditions refer to failure to repair leaking equipment on schedule or failure to 

correct a control device which exceeds or operates outside of design specifications. If a 

report is required, it shall identify the facility and provide the dates of hazardous waste 

management unit shutdowns that occurred during the preceding semiannual reporting 

period. For each month during the semiannual reporting period, the TSDF is required to 

report: (1) the ID number of each valve, pump, or compressor for which a leak was not 

repaired or required, and 2) the date, duration and cause of any control device 

exceedance, and any corrective measures taken. 

40 CFR Part 265, Subpart BB contains no reporting requirements. 

3.1.5 Reviewing Reports 

Although reports are the primary mechanism by which a facility documents 

compliance with the equipment leak rules, they are of limited value to the inspector as a 

means of identifying specific violations or of substantiating noncompliance. From a 

regulatory point of view, review of reports can only substantiate noncompliance on the 

basis of: 

• Failure to submit a report 

• Late submittals 

• Missing or incomplete report content 

• Self-reported violations 

For purposes of determining compliance, the primary focus of an inspector's 

review of reports should be on the issue of report completeness. Other issues (accuracy, 

equipment classification, monitoring performance, etc.) require some further interaction 

with the review of records and/or on-site inspections. 

During the first year or two of developing an equipment leak program at a 

regulated facility, it is possible that a facility may overlook or be unaware of some 

reporting requirements. Equipment subject to partial exemptions or non-routine reporting 

schedules may be the most likely to be overlooked. However, once a facility has 

submitted a report that the Agency accepts as complete, the facility is unlikely to regress 

from this established standard. Subsequent violations of reporting requirements are most 

likely to be associated with changes in the process, e.g., failure to add/delete equipment as 

a result of maintenance or process modifications. 

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A report may contain "self-reported" violations such as failure to attempt 

equipment repair within schedule or during process shutdown. An inspector should, of 

course, review each report carefully and note such "self-reported" violations for followup. In many cases, these events prove to be recordkeeping or reporting errors rather than 

true violations. For example, transcription errors may occur between records and reports 

(e.g., a valve is monitored as leaking at 1,500 ppm but is transcribed to a report at 15,000 

ppm), or a maintenance crew may forget to submit repair invoices. By routinely following 

up on such questions, an inspector will help the facility to recognize inadequacies in its 

equipment leak compliance program and such reporting errors should decline. 

Many facilities employ sophisticated monitoring systems and databases to minimize 

both the labor hours and opportunities for clerical errors associated with large scale 

monitoring systems. Monitoring equipment can be equipped with a data logger containing 

the sequential ID numbers for all equipment within a process area. At each monitoring 

point, the data logger automatically records the highest instrument reading obtained at that 

point. This data can then be downloaded to a database that contains: (1) all the relevant 

information for each piece of equipment, and (2) a report generator which automatically 

prepares the appropriate report for each process area. 

Sophisticated systems can also generate erroneous reports, as a result of lack of 

foresight in their preparation or due to a lack of human attention to the system. As an 

example, some data logging systems employ a default value of zero or carry forward the 

reading from the previous monitoring. As a result, these systems may report a numerical 

reading for a piece of equipment, even if that equipment was not monitored. Conversely, 

these systems may not be able to record readings from new equipment until the equipment 

data has been entered into the database. 

Ultimately, the best strategy for effective review of reports by an inspector is 

developed familiarity. This includes familiarity with the recordkeeping and reporting 

requirements of the rules, and familiarity with how the regulated facility is performing its 

monitoring, data management, leak repair, and reporting programs. By developing such 

detailed knowledge about a specific facility, an inspector will be better prepared to 

interpret and understand that facility's reports. This developed familiarity requires an 

ongoing balance of effort which includes on-site inspection and review of records. 

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3.2 RECORDKEEPING 

3.2.1 Part 60 Subpart VV and Part 61 Subpart V & J 

All of the equipment leak regulations require the maintenance of extensive, 

detailed records that can be readily accessed at the plant site. Specific records that are 

required include: 

• A list of ID numbers for all equipment subject to the requirements (except 

for welded fittings or connectors under some rules). 

• A list of equipment ID numbers for equipment designated for "no 

detectable emissions" or complying with the less than 500 ppm above 

background standard. The no detectable emissions designation must be 

signed by the owner or operator and requires an annual compliance test and 

a record of the date of the compliance test, the background level measured, 

and the maximum instrument reading measured at the equipment. 

• A list of equipment ID numbers for pressure relief devices required to 

comply with the standards for pressure relief devices in gas/vapor service. 

• A list of ID numbers for equipment in vacuum service. 

If a closed-vent system and a control device are used to control fugitive emissions, 

the records for this equipment must include: 

• Detailed schematics, design specifications, and piping and instrumentation 

diagrams. 

• Dates and descriptions of any changes in the design specifications. 

• A description of the parameter(s) monitored to ensure that a control device 

is operated and maintained in conformance with the design, and an 

explanation of why that parameter was selected for monitoring. 

• Periods when the closed-vent systems and control devices are not operated 

as designed, including periods when a flare pilot light does not have a 

flame. 

• Dates of start-ups and shutdowns of the closed-vent systems and control 

devices. 

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A dual mechanical seal system that includes a barrier fluid system is an alternative 

for reducing emissions from pumps and compressors. If a dual mechanical seal system 

with a barrier fluid system is used, the following information must be recorded: (1) the 

design criteria that indicates failure of the seal system, the barrier fluid system, or both; (2) 

an explanation of the choice of this design criteria; and (3) documentation of any changes 

to the criteria and the reasons for the changes. 

The records also must contain a list of ID numbers for valves that are designated 

as “unsafe to monitor,” an explanation for this designation, and the plan for monitoring 

each valve. The same records are required for valves designated as “difficult to monitor.” 

For valves complying with the skip-period provisions, a schedule of monitoring and a 

record of the percent of valves found leaking during each monitoring period must be kept 

on file. 

Certain criteria allow a facility to be exempted from the requirements (see Chapter 

2). If a facility claims an exemption, then it must maintain a log that contains information, 

data, and analyses to support its exemption declaration. For example, 40 CFR 63 

Subparts V & J stipulate that the following information shall be recorded: (1) an analysis 

demonstrating the design capacity of the process unit, and (2) an analysis demonstrating 

that equipment is not in VHAP service. 

For each compliance monitoring test conducted, a record of results must be 

retained. This includes the monthly leak monitoring for pumps and valves, as well as the 

annual no detectable emissions monitoring for pumps, compressors, valves, and closedvent systems. Any monitoring for alternative standards also must be documented. 

Other non-periodic circumstances require compliance monitoring. A pressure 

relief device must be monitored within five calendar days after a pressure release to 

confirm that no emissions are detectable. If a pump or valve in heavy liquid service, 

flange, or other connector is suspected of leaking, this equipment must be monitored 

within five days. If a leak is detected and repair is attempted, the component must be 

monitored to determine if the repair attempt was successful. Records must be kept of the 

findings of all such monitoring tests. If a leak is detected, the equipment must be 

identified as a leaking component by attaching an ID tag to the leaking equipment. The 

tag must be weatherproof and readily visible. A tag may be removed after the equipment 

has been repaired and retested successfully. The tag may be removed from a valve, 

however, only after it has been repaired and monitored for two successive months with no 

detected leak. 

When leaks are detected, records on each leak must be kept and maintained for 

two years. For each detected leak, the equipment ID number, the instrument and operator 

ID numbers, and the date the leak was detected must be recorded. The date of each repair 

attempt and an explanation of each method applied should be recorded. If the leak is 

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corrected, then the date of successful repair should be entered in the log. If the repair is 

unsuccessful, the operator should record that the maximum instrument reading of the 

monitoring after the respective repair was above the applicable leak limit. 

If a leak is not repaired within 15 calendar days of being detected, "repair delayed" 

should be entered in the log, and the reason for the delay should be discussed. If the 

reason for the delay is that the repair could not be attempted until a process shutdown, 

then the person who made the decision to delay repair must sign the log. If process unit 

shutdowns occurred while the leak remained unrepaired, the dates of these shutdowns also 

must be recorded. Finally, the expected date of successful repair of the leak should be 

entered for these delinquent leaks. 

3.2.2 Recordkeeping for the HON 

The HON incorporates virtually all of the recordkeeping requirements of the NSPS 

and NESHAP standards, with significant additions and extensions. For example, all 

equipment ID numbers are required to identify the process area in which the equipment is 

located. Additional equipment addressed by the HON includes agitators, product 

accumulator vessels, and bottoms receivers equipped with closed-vent and control 

systems, pressure release devices equipped with upstream rupture disks, instrumentation 

systems, batch process equipment, enclosed-unit processes, and equipment in HAP service 

less than 300 hours per year. Substantial new recordkeeping requirements are associated 

with equipment in a quality improvement program (QIP). 

Connectors need not be identified individually, but the number of connectors in 

each process area are to be recorded. Screwed connectors are to be individually 

identified. Additionally, each connector which has been disturbed since the last 

monitoring is to be identified and the date and result of follow-up monitoring recorded. 

The HON records require a monitoring schedule by process area for valves and 

connectors. Both valves and connectors that are designated as difficult to monitor, unsafe 

to monitor, or unsafe to repair are to be identified in the records. The records must also 

ID valves and connectors which have been removed from service and claimed for emission 

reduction credits. 

Tagging of individual components within each process area is not required by the 

HON, so long as other identification requirements are met. Tagging and reporting 

requirements for leaking equipment are the same as the NESHAP regulations. For 

equipment which cannot be repaired within the applicable deadline, the HON allows 

written procedures for determining that such equipment qualifies for delay of repair status 

to be included in the records. 

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Visual inspections required by the HON are to be recorded. These are to include 

documentation that the inspection was conducted, the date of the inspection, and detailed 

records for leaking equipment identified in these inspections. 

When a facility elects to periodically pressure test a batch process, each regulated 

product and the time in service for each product are to be recorded. Pressure test records 

are to include the date of each test and any visual observation of leaks. When equipment 

fails a pressure test, records are to be kept of each leak repair attempt, the date of each 

repair, the repair methods employed, and the reasons for any delay of repair. 

Enclosed-vent process units and the HAPs they handle are required to be identified 

in the records. Enclosed-vent process units are enclosed in such a manner that all 

emissions from equipment leaks are vented through a closed vent system to a control 

device. The records are to include a schematic of the process unit, enclosure, and closed 

vent system and a description of the system used to create the negative pressure in the 

enclosure. 

A QIP generally consists of information gathering, determining superior 

technologies, and replacing existing equipment with the superior technologies until the 

required base performance levels are achieved. The recordkeeping requirements basically 

stipulate dates and documentation of QIP activities. The Demonstration of Further 

Progress QIP for valves requires additional recordkeeping for monitoring and repair 

activities. The Technology Review and Improvement QIP for valves or pumps extends 

recordkeeping requirements to include: equipment construction and use data, process 

stream data, inspection of leaking valves removed from service or of pumps that leak 

frequently, and analysis of equipment performance based on these records. 

3.2.3 RCRA Recordkeeping Requirements 

The RCRA equipment leak standards stipulate that records be maintained in the 

facility operating record or in a log maintained in the facility operating record. The 

following information is to be maintained for each piece of equipment to which Subpart 

BB applies: 

• Equipment ID number and hazardous waste management unit 

identification. 

• Approximate location within the facility. 

• Type of equipment (e.g. pump or pipeline valve). 

• Percent-by-weight total organics in the hazardous waste stream at the 

equipment. 

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• Physical state of hazardous waste at the equipment (e.g., gas/vapor or 

liquid). 

• Method of compliance with the standard. 

• A list of ID numbers for all subject equipment. 

• A list of ID numbers for equipment designated for "no detectible 

emissions," with signature of the owner or operator. 

• A list of ID numbers for pressure relief devices subject to the standard. 

• For each compliance test required by the standards, the date, the 

background level, and the maximum instrument reading measured at the 

equipment. 

For each leak detected in the compliance tests, the following information is to be 

recorded in a log and maintained for three years: 

• The instrument, operator, and equipment ID numbers. 

• The date evidence of a potential leak was found. 

• The date the leak was detected and the dates of each repair attempt. 

• Repair methods applied in each attempted repair. 

• "Above 10,000" if the instrument reading following a repair attempt 

exceeds 10,000 ppm. 

• "Repair delayed" and the reason if a leak is not repaired within 15 days of 

discovery. 

• Delay of repair documentation for applicable valves. 

• Owner or operator signature when repairs cannot be effected without a unit 

shutdown. 

• The expected date of repair for leaks not repaired within 15 days. 

• The date of successful repair. 

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The records are to include design documentation and monitoring, operating, and 

inspection information for each closed vent system and control device. In addition, a 

performance test plan and documentation of performance test results are required when 

test data is used to demonstrate control device performance. Control devices not 

otherwise identified in the regulations are also required to record monitoring and 

inspection information indicating proper operation and maintenance of the control device. 

A list of valves designated as unsafe to monitor and a list of valves designated as 

difficult to monitor are to be maintained. Each list is to include an explanation of the 

designation and a plan for monitoring each valve. Recorded information for other valves 

must include (1) a schedule of monitoring and (2) the percent of valves found leaking 

during each monitoring period. 

The following information is to be maintained in a log for determination of 

applicable exemptions: (1) analysis determining the design capacity of the hazardous waste 

management unit, (2) a statement listing the hazardous waste influent/effluent to each unit 

and an analysis determining whether these hazardous wastes are heavy liquids, and (3) upto-date analysis, supporting information, and data used to determine applicability of the 

standards. 

3.2.4 Reviewing Records 

When reviewing equipment leak records, it is important to keep in mind the 

primary purpose of the records, which is verification of the information in the reports and 

documentation of other elements of program performance such as performance of 

monitoring, adherence to repair schedules, documentation of visual inspections, etc. 

Review of records should be guided by the inspector's prior review of the reports and 

should focus on using the records to (1) confirm the accuracy and content of the reports 

and (2) determine that recordkeeping requirements of the applicable standard are complied 

with. 

Specifically, records should be investigated to confirm that all components are 

indicated as being monitored as reported and to confirm the number of reported leaks. 

Additionally, such information should be compared with the inventories of total 

components by type of service as recorded in the initial report for each facility. There will 

normally be some fluctuation in the total number of components inspected during each 

monitoring period due to a variety of factors such as leak/repair status and equipment 

retired from or added to a process. A detailed review of the records may be necessary to 

resolve all of the apparent anomalies in process areas with a large number of components 

or where substantial modifications are underway. Failure to record and report such 

changes may result in a violation of the standards. 

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Records should also be reviewed to confirm the performance of repairs and followup monitoring on all reported leaks. For example, if a valve was reported leaking, check if 

the records confirm the following: (1) a first attempt to repair within five days, (2) 

completion of repair within 15 days, and (3) monthly monitoring for two months before 

return to quarterly monitoring. If the valve was not repaired but was scheduled for repair 

at the next shutdown, was this an appropriate classification (i.e. is the 

explanation/documentation of the classification reasonable and signed by the proper 

official)? The complete list of components scheduled for repair at the next shutdown 

should be reviewed to determine the appropriateness of this classification. 

As is the case with reports, only a limited number of specific violations can be 

identified and confirmed solely through a review of records. Establishing such a violation 

is primarily a process of identifying something which is missing. Facilities are in direct 

noncompliance under the following situations: 

• Failure to record leaks and dates of repairs, 

• Failure to record the reason for delaying repair of leaks past an allotted 

time frame, 

• Failure to develop a schedule to observe visual emissions from flares, 

• Failure to perform emission testing for control devices (except in the case 

of flares), and 

• Failure to record periods when the control device is not operating. 

Finally, each facility will develop and implement its own form of recordkeeping. 

The variety and inconsistency of recordkeeping formats from one facility to another is a 

problem which an inspector has little opportunity to influence or correct. For example, 

the availability and utility of work orders to support recordkeeping or to confirm/resolve 

errors and oversights will vary from facility to facility. To be effective, an inspector needs 

to develop a degree of familiarity with the data collection and management system of each 

facility in his or her area of responsibility. 

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3.3 STRATEGIES FOR REVIEWING REPORTS AND RECORDS 

As has been previously discussed, the report and recordkeeping requirements of 

the equipment leak regulation do not provide enough information for an inspector to make 

a complete determination of compliance. The report and recordkeeping review activities 

provide the basis for determining whether a facility is in compliance with the report and 

recordkeeping requirements and provide the informational basis for more in depth 

inspection activities. Strategies available to the inspector to improve the effectiveness of 

both functions include (1) requesting additional information and 2) coordinating the 

review process with on-site inspections to reinforce the determination of compliance. 

An inspector can generally request that a facility provide any records specified by 

the equipment leak regulations in the form of a supplementary report. A thorough 

understanding of the records required by the standards and the data management systems 

of the individual facilities will enable an inspector to request additional information in a 

format that is reasonable for the facility to comply with and useful to the inspector's 

objectives. Other information not specifically referenced in the regulations may also be 

available to the inspector. Process flow diagrams and/or schematics of individual process 

areas can be particularly useful as a means of orienting oneself prior to a site visit, 

reviewing the appropriateness of various equipment designations (e.g., type of service, 

dangerous to monitor), and for cross-referencing data from various records sources. 

Work repair orders and/or repair invoices are another source of potentially useful 

information, especially when it is necessary to reconcile apparent gaps or oversights in the 

records. 

Required reports and supplementary information provided by the facility are useful 

means of preparing for on-site inspections. In addition, information collected on-site or 

requested during a site visit can be used for follow-up review and evaluation of 

compliance status. Collecting or requesting information for review after completion of a 

site visit allows the inspector to make more efficient use of available time while on-site. 

Such information can be used to supplement and/or document inspection field notes and 

observations. Additionally, such information can be compared with the initial review of 

semiannual reports to resolve any lingering questions. 

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CHAPTER 4 

COMPLIANCE/ASSESSMENT THROUGH ON-SITE INSPECTIONS 

On-site inspections are a critical component in evaluating compliance with the leak 

detection rules and evaluating the effectiveness of facility LDAR monitoring activities. 

Due to the complexity of the standards and the large numbers of emission points at a 

typical facility, it is imperative that an inspection be conducted in a systematic fashion. An 

inspector may choose to use a portable VOC analyzer to conduct direct leak checks of 

regulated equipment, but it is also possible to conduct a compliance inspection without the 

use of such equipment. The first portion of this chapter addresses the conduct of a walkthrough inspection without an analyzer; the second portion addresses the conduct of 

inspections with the direct monitoring of regulated equipment. 

Equipment leak inspections encompass a broad range of potential activities. The 

specific content and organization of inspections will vary according to the priorities or 

objectives of the inspector and/or policies of the agency. For example, it may be necessary 

to devote an entire inspection to on-site interviews and examination of records addressing 

the appropriate classification of equipment. Short, follow-up inspections may be 

combined with other on-site activities. This chapter uses a simplified inspection format to 

illustrate the important elements of organizing and conducting inspections. 

4.1 WALK-THROUGH INSPECTIONS 

A complete equipment leak inspection program includes pre-inspection activities, 

on-site activities, and post-inspection review and reports. The pre-inspection activities 

help the inspector become familiar with the facility, contributes to the selection of specific 

process areas or components to be inspected, and may determine the actual timing of the 

inspection. On-site activities include review of records, interviews with plant personnel, 

inspection of regulated equipment, and observation of monitoring procedures. Postinspection activities include additional review of records and other information, 

preparation of the inspection report, and establishing the foundation for subsequent 

inspections. 

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4.1.1 Pre-Inspection Activities 

The purpose of pre-inspection activities is for the inspector to develop a general 

understanding of the plant under investigation, the processes employed, and products 

produced. Additionally, the inspector should be familiar with the applicable regulations 

and understand what types of information are required to determine compliance prior to 

the on-site inspection. Good preparation helps to select those units suspected or detected 

as being compliance problems, determine the appropriate timing of the inspection, and 

improve an inspector's efficiency while on-site. Caution: While it is meaningful to gain 

an impression of the overall situation through these pre-inspection activities, it is 

equally important than an inspector not prejudge a facility based only on the 

preliminary information. Compliance determination should be finalized only after 

the on-site inspection and follow-up activities are completed. 

It is important that the inspector keep detailed records for each inspection. An 

inspection notebook should be started during the pre-inspection time period so that all 

information is contained in a central location for the entire inspection. Since the notebook 

may be used to form the premise of the inspector's report and as evidence in legal 

proceedings, it is critical that the inspector substantiate the facts with tangible evidence 

such as pertinent observations, photographs, copies of documents, descriptions of 

procedures, unusual conditions, problems and statements from facility personnel. 

4.1.1.1 Report Reviews and Other Information Sources 

Sources subject to the various equipment leak standards are required to submit a 

preliminary notification and/or initial report which provides general facility information, 

process unit information, and the inventory of all subject equipment with details of 

individual components. These initial documents should be evaluated for completeness, as 

discussed in the preceding chapter. If any aspect of the initial documents are incomplete, 

the inspector should record this in the inspection notebook. 

Each of the regulations also require the submission of semiannual or periodic 

reports. The inspector should evaluate the most recent of these reports for completeness 

and compliance with the requirements. Additionally, these reports should be compared 

with each other and with the initial reports to determine the consistency of information. 

Any inconsistencies or omissions of required information should be recorded in the 

inspection notebook. 

Following the review and evaluation of these reports, the inspector should review 

previous inspection reports and related documentation such as field notes, post-inspection 

correspondence, and violation notices. These will identify previous deficiencies and 

related issues, may record the estimated schedule of additions or 

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reconstructions the facility is planning to implement, and may record specific actions the 

facility has committed to with respect to improving its compliance with the equipment leak 

regulations. 

The omissions, inconsistencies, unclear information, or question areas identified by 

the above review should be noted in the inspection notebook. A complete and well 

organized list of questions should be developed from these notations so that plant 

personnel can be questioned or plant records checked during the inspection. 

Inconsistencies by themselves are not uncommon and do not necessarily indicate 

violations. They may indicate poor implementation of recordkeeping and reporting which 

can be corrected at the facility without the issuance of formal citations. 

In the case of new regulations (e.g., the HON in 1995/96) or new plant 

construction, the only source of information specific to the equipment leak programs may 

be the initial report. In such cases, the inspector should examine agency files to determine 

if other process areas at the facility have been previously regulated under other equipment 

leak rules. If so, these reports may provide some background about the facility's 

familiarity and performance with respect to equipment leak regulations. Agency files 

should also be examined to obtain other compliance information, correspondence, 

complaints, etc. regarding the facility. Other types of permits and reports, such as those 

for other air regulations, wastewater, hazardous waste, or toxic substance permits, should 

also be reviewed. A good example is TRI reports, submitted pursuant to EPCRA 

requirements. Information contained in the initial equipment leak reports should be 

compared with these other sources of information to assess the consistency between the 

details reported. 

Other inspectors who are currently or formerly assigned to the facility in question 

should be interviewed for their experience and insight. For example, RCRA and air 

inspectors should perform cross-media reviews of each other’s inspection reports. 

Finally, up-to-date schematics or flow charts of regulated process areas at the 

facility should be obtained to facilitate understanding of the physical site layout. A major 

problem that confronts the inspector is determining if equipment exists in the facility that is 

subject to the standard, but is not listed in the in-plant records and therefore is not being 

monitored and/or does not meet the equipment specifications. This may be the most 

difficult part of an inspection. One method of addressing this problem is to request a 

process unit material balance with a corresponding simplified flow diagram. This 

information could then be reviewed in detail to determine if there appears to be equipment 

which should be listed and is not. If such areas exist, then the on-site inspection or followup inspection should address this issue. 

4.1.1.2 Inspection Timing and Scope 

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An additional consideration during pre-inspection preparations should be the 

nature of the inspection itself. Does the purpose of the inspection require an unannounced 

visit or is some degree of notification acceptable? While it is desirable to maintain some 

degree of flexibility as to the specific plant areas and records you will examine while onsite, it is also necessary to allow key plant personnel an opportunity to rearrange their 

activities to accommodate the inspection. The inspection involves the review of many 

records and interviews with key company officials. Additionally, plant personnel should 

be available to accompany the inspector during the facility walk-through and to answer the 

inspector's questions. 

If you plan to examine leak monitoring activities of plant personnel or their outside 

contractors, obtain their current monitoring schedule. You need to ensure that routine 

monitoring activities will be conducted during your visit, and you may want to select an 

inspection date which coincides with monitoring of specific process areas. 

Another aspect of inspection preparation involves making an assessment of what 

can be accomplished within the time available to conduct the inspection. To make the best 

use of limited time and resources, it is often useful to structure the inspection on the basis 

of what can be accomplished within one full day. 

For the inspection program discussed in this section, an initial interview with plant 

officials and the site walk-through can be accomplished during the morning, with the 

afternoon devoted to review of records and a final interview addressing any questions or 

observations resulting from the inspection. It may be necessary to review some of the 

records prior to conducting the site walk-through, especially if the records are needed to 

identify specific equipment to be inspected. In general, the site walk-through should be 

completed before reviewing the records in detail to assure that enough time is available for 

the walk-through. If the record review cannot be completed on-site, copies can generally 

be taken back to the office. 

It is useful to become familiar with the normal workday schedule at each plant and 

to schedule your inspection accordingly. For example, the equipment leak monitoring 

personnel may work an early shift (e.g., 6 am to 3 pm) so that maintenance personnel can 

conduct same-day equipment repairs on a later shift. At a small facility which employs a 

contract monitoring service, monitoring personnel may only be available one or two days 

per week or during alternating weeks. It is generally difficult to obtain useful observations 

or interviews if you schedule a process area walk-through during the lunch break. More 

importantly, if you are flexible in the scheduling of inspection activities, plant personnel 

may be more relaxed and responsive to your inquiries. 

4.1.1.3 Health and Safety Planning 

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A critical aspect of pre-inspection planning includes efforts to ensure that 

personnel safety measures are in place. Contaminants of concern identified during the 

preliminary review of the facility should be reviewed for exposure impacts, via dermal or 

inhalation pathways, to ensure appropriate personnel safety gear is donned for the 

inspection. Further, if potential risks exist, the inspector should wear a modified level C 

and be able to don a respirator if monitoring equipment indicates levels in the breathing 

zone exceed acceptable levels. Finally, when you schedule an inspection, review with 

company officials what safety equipment is needed and what, if any, safety equipment the 

company will provide. 

4.1.2 On-Site Inspection 

When you arrive at the facility, notice if there are any strong odors or visible 

emissions. If there is a visible emission or strong odor, make sure it is thoroughly 

documented before entering the facility. Try to find out the cause of the visible emissions 

or odor after you have introduced yourself. 

4.1.2.1 Initial Interview 

Once the inspector has identified himself or herself and has been granted entry to 

the facility, the initial interview should be conducted. The objective of the interview is to 

inform the facility officials of the purpose of the inspection, the authority under which it 

will be conducted, the procedures to be followed, and your agenda for the day of the 

inspection. 

Discussion of the agenda should include an explanation of how you plan to 

perform the inspection and should address any adjustments to your schedule necessitated 

by plant operating schedules and conditions. With regard to leak monitoring activities, it 

is probably best to observe calibration and monitoring procedures as they are scheduled 

for that day, rather than to observe a possibly rehearsed demonstration of these activities. 

Final specification of the records you wish to inspect should be made at this time, along 

with agreement as to when they will be available and where you can review them. 

An important component of the inspection involves the evaluation of how well 

company officials understand the applicable regulations and how effectively they are acting 

to achieve compliance. The inspector should have key plant officials explain the 

compliance program of the facility: including a general discussion of problems/solutions, 

plant quality assurance procedures, and compliance program goals of the plant. With 

regard to the inspection agenda for the day, the inspector should verify that the sources 

are subject to the standard and should ask for a description of the process areas, principal 

products, and location of major emission points. 

4-5
Before proceeding into the process areas, the inspector should review plant safety 

procedures and confirm that all appropriate safety equipment is available. Finally, plant 

officials should be advised of their right to request confidential treatment of trade secret 

information. Company officials may review the inspection notes at the end of the 

inspection and mark trade information confidential. 

4.1.2.2 Leak Monitoring Activities 

A key element of the facility inspection involves evaluation of the leak monitoring 

program. This activity may include: interviewing monitoring personnel, observing the 

calibration of leak detection equipment, and observing facility personnel perform leak 

detection monitoring and spot checking of equipment sources for leaks. 

Some facilities conduct monitoring with their own personnel, while others employ 

an outside contractor to perform the leak monitoring. If in-house personnel conduct the 

monitoring, an inspector may want to review the training and resources provided to the 

employees. If an outside contractor is employed, the inspector should determine if the 

facility employs any oversight or quality assurance procedures to evaluate the performance 

of the contractor. Other pertinent items include: how monitoring personnel report leaks, 

how repairs are scheduled, and how follow-up monitoring is scheduled for repaired 

equipment. 

The competency of the personnel who conduct the monitoring may be evaluated 

both through observation and direct interviewing. The inspector should discuss the plant 

procedures and schedules for monitoring, the recording of monitoring results, general 

information regarding the analyzers in use, requirements of Method 21, and any other 

areas the inspector determines to be of importance. These could include training received, 

task supervision, and ancillary duties performed by the leak monitoring personnel. 

The leak detection equipment used to document facility compliance must be 

calibrated on a routine basis. The inspector should observe calibration procedures 

performed by the facility or contractor personnel who normally perform the routine 

monitoring. The calibration precision tests, response time, and response factor tests reveal 

whether the instruments are operating properly for the specific applications. The inspector 

should witness the calibration procedures and should note any deviations from the Method 

21 procedures. 

A number of other factors can be important such as: probe cleanliness, probe 

leakages, gas flow rates, improper warmup period, incorrect zero, or meter adjustment. If 

the meter readout cannot be adjusted to the proper value, a malfunction of the analyzer is 

indicated and corrective actions are necessary before using the analyzer. The inspector 

should verify that the correct calibration gases are used and that the gases are within the 

4-6
proper range. The inspector should record the instrument response time, response factors, 

and calibration precision tests. 

After the calibration procedure is complete, the inspector should observe the plant 

personnel's or private contractor's technique in performing actual leak detection 

measurements. The plant personnel should be able to correctly monitor fugitive emissions 

from all the equipment types at the plant site. Additionally, the plant personnel should be 

able to correctly determine background concentrations. Any deviations from Method 21 

procedures should be noted. Techniques for correctly monitoring certain equipment items 

are described in the following paragraphs. See Appendix E in Volume II for a more 

detailed discussion of monitoring techniques. 

Fugitive leaks from valves occur primarily from the valve stem packing gland. The 

normal procedure is to circumscribe the valve stem with the probe held at the stempacking interface. Maintaining such a close proximity to the stem is necessary in order to 

obtain accurate measurement because of the relatively poor capture effectiveness of the 

probe design. The presence of strong cross-draft wind further reduces the probe capture 

capability. For these reasons the proper placement of the probe is critical. It should be 

noted, however, that this monitoring requirement dictates that the inspector position 

himself or herself in the immediate vicinity of the leak because most probes are relatively 

short in length. Caution: If the inspector detects unsafe conditions, he or she should 

stop observation and inform plant personnel. All involved parties should follow 

their organization's safety procedures. 

Certain monitoring procedures can be employed to minimize the risk of such 

exposure. Whenever feasible, equipment to be monitored should be approached from 

downwind. Concentrations of equipment in a sheltered area should be approached 

relatively slowly from a more open area. In both cases, use your sense of smell and visual 

observation of the instrument background reading as an early means of detecting elevated 

concentrations. 

Fugitive emissions from pumps occur from the pump shaft seal used to isolate the 

process fluid from the atmosphere. Monitoring must be performed within one centimeter 

of the seal and the rotating shaft. Caution: A rigid probe tip should not be used near 

the rotating shaft because it could break if the monitoring personnel were not able 

to hold the probe absolutely steady during the measurement. A flexible tip is usually 

added to the end of the rigid probe when sampling pumps. If the housing configuration 

prevents a complete traverse of the shaft periphery, sample all accessible portions. 

Additional points on the pump or compressor housing where leaks could occur include 

flanges and other connections, and these should be sampled. Also, look for liquid leaks 

from the stuffing boxes of pumps. 

4-7
Care must be exercised when monitoring sources, such as valves and pumps, that 

handle heavy liquid streams at high temperatures. Relatively nonvolatile organic 

compounds can condense in the probe and detector. Both the instrument response to the 

emissions and the instrument return to zero may be slowed due to the condensation of 

these compounds. 

Fugitive leaks from flanges or other connectors typically occur at the flange or 

connector sealing interface. For all connections, the probe should be positioned at the 

outer edge of the flange-gasket interface, and monitoring should be conducted over the 

entire circumference of the flange. 

In most cases, the configuration of pressure relief devices prevents sampling at the 

sealing interface. However, for those pressure relief devices equipped with an enclosed 

discharge pipe, extension, or horn, the sample probe inlet should be placed at the 

approximate center of the exhaust area relative to the atmosphere. Also, sample at any 

"weep hole" at the bottom of such devices. 

Certain fugitive leak sources are subject to a "no detectable emission" regulation, 

i.e., the difference between the background organic vapor concentration and the 

concentration measured at the source should not be greater than 500 ppmv. The 

background concentration is determined by placing the probe one to two meters upwind 

of the source. If other equipment interferes with the background measurement, the 

upwind monitoring location can be as close as 25 centimeters. 

Leak monitoring personnel should record the highest instrument reading obtained 

at each piece of equipment. For fugitive VOC sources that have a highly variable leak 

rate, the maximum sustained concentration or maximum repeated concentration observed 

should be recorded. 

During observation of the leak monitoring, the inspector should note how well the 

monitoring personnel keep track of their monitoring equipment. While monitoring is 

underway, the probe tip should be routinely checked and cleaned out as necessary. 

Instrument background readings and return to zero rates should be monitored periodically. 

Also, note whether monitoring personnel are equipped with and using appropriate tags to 

mark leaking equipment. 

Finally, note the number of equipment components and the number of leaks 

detected by the monitoring personnel. These can be used to calculate rough estimates of 

leak monitoring rates (i.e., valves per hour or total components per hour) and component 

leak rates (e.g., eight leaking valves out of 150 tested equals six percent leak rate). These 

rates can be compared to leak monitoring rates and component leak rates calculated from 

the records for the same or similar process areas. A large and consistently repeated 

difference between reported rates and observed rates may indicate that monitoring 

4-8
personnel are changing their procedures in some consistent fashion while being observed 

by the inspector. 

In addition to observing the performance of routine monitoring, the inspector may 

wish to have the monitoring personnel spot-check a representative sample of equipment 

for leaks. This should be done by observing personnel perform leak detection monitoring 

on each type of equipment subject to the standard. The spot-checks should include: 

• recently leaking devices; 

• "no detectable emission" devices; 

• exempt devices (verify compliance). 

Finally, if a facility is using closed vent systems and control devices, ensure 

compliance with minimum temperature, residence time, efficiency and no detectable 

emissions requirements. If flares are being used, inspect for no visible emissions as 

determined by Reference Method 22. 

4.1.2.3 Process Area Inspection 

In addition to observing the leak monitoring program, an inspector should devote 

some time to observation of the process area itself and interviewing process personnel 

regarding their roles in the equipment leak program. By doing so, an inspector can 

determine compliance with observable requirements such as equipment tagging and gain a 

better understanding of the program implementation. 

The degree to which process area personnel will be aware of and involved in the 

equipment leak program will vary from facility to facility. At a minimum, there should be 

a designated individual (process area chief or shift foreman) responsible for (1) 

documentation of visual inspections, (2) maintenance of on-site logs, and (3) coordination 

between leak monitoring and equipment maintenance. Other areas in which process 

personnel may be involved include (1) performance of first attempt at repair, (2) oversight 

or quality review of leak monitoring personnel, and (3) on-site responsibility for 

equipment markers and removable equipment (e.g., end caps or plugs). 

Perhaps one of the most important areas to discuss with process personnel is the 

issue of coordination between leak monitoring and equipment maintenance personnel. 

Lack of communication between these groups is a significant source of errors and 

compliance problems. How well the facility understands these problems and the types of 

procedures undertaken to correct or prevent such oversights can reveal a lot about the 

development and effectiveness of a facility's equipment leak program. 

4-9
Observation of the process area should include verification of component tagging, 

observation of end caps or plugs on open ended lines, inspection of sampling connection 

systems and equipment in vacuum service, and evaluation of the operation of various 

control devices. 

Errors and oversights with respect to component tagging requirements are a 

common problem which can be directly observed by the inspector. All equipment that is 

scheduled for repair or to be monitored following repair must be clearly labeled. An 

inspector can use records and reports to develop a list of components that should be 

tagged and can then directly inspect those components to confirm the tags are being 

applied and maintained. For equipment that will not be repaired until the next process 

turnaround, the inspector can review the process equipment where the component is 

located to confirm that such repairs cannot be accomplished without a process shutdown. 

Open-ended lines are frequently out of compliance (e.g., no plug or end cap) and 

can be directly cited as a violation as a result of on-site inspections. Plant personnel may 

lose or misplace end caps or plugs when such lines are opened, then simply forget about 

them. An area-wide maintenance activity may result in numerous lines with missing caps. 

Sampling connection systems should be examined to confirm that the vent properly 

returns process fluids to the process. Similarly, equipment in vacuum service should be 

examined to confirm that equipment to create such a vacuum is in place, operating, and 

venting to a control device. 

Each dual mechanical seal with barrier fluid system is required to be equipped with 

a sensor that monitors the chosen criteria to detect a system failure. This sensor must be 

checked daily or be equipped with an audible alarm. The inspector should verify that the 

sensor has an alarm which is working properly or that the sensors are being monitored 

daily. 

If a control device is being used to control equipment leak emissions, the inspector 

needs to observe several items. The first is the identification of the control device and the 

manner in which the owner or operator is monitoring its operation. Following are several 

questions that should be answered during the inspection: 

• Why type of control device is used? 

• What is the claimed control device efficiency? 

• Is the efficiency measured (tested) or calculated? Obtain a copy of any of 

these test results or calculations. 

4-10
• For incineration devices, what is the combustion temperature (from the 

field or control room)? 

• For each type of control device in use, what are the critical parameters that 

demonstrate compliance (e.g., adsorber pressure drop/regeneration cycle 

time, scrubbing fluid flow rate/pressure drop, final temperature leaving 

condenser)? 

• For flares, during normal operation what is the net heating value and exit 

velocity of the flare gas? Is the velocity and net heating value of the flare 

gas measured (tested) or calculated? Obtain copies of these test results 

and/or calculations. Check the flame indicating device (probably a 

thermocouple readout) in the field or control room for proper operation. 

Observe the flare for visible emissions. 

The inspector should evaluate the parameters chosen and the rationale for this 

selection to determine if these parameters are appropriate to monitor proper operation for 

the type of control device. This evaluation may need to be done off-site if the inspector is 

not readily familiar with a particular type of control device. 

4.1.2.4 Inspection of Records 

Recordkeeping requirements and strategies for the review of records have been 

addressed in Chapter 3. The primary objective of the record inspections is to minimize 

fugitive emissions through requiring adherence to the recordkeeping requirements of the 

regulation. Records that are required to be kept by the facility (and not reported) should 

be reviewed by the inspector during the on-site inspection. The inspector should 

determine what information needs to be obtained to document compliance. In particular, 

the inspector should identify missing information, incomplete data or reports and 

inconsistencies in the available background material, and specifically seek to extract this 

information from on-site facility reports for the purpose of making a compliance 

determination. Likewise, if noncompliance is suspected, the inspector should concentrate 

efforts on obtaining necessary documentation for verifications. 

The first step in the records review should be to determine if the records are 

complete according to the regulations. After determining the completeness of the records, 

a check for consistency and validity should follow. An inspector should take along a few 

of the most recent semiannual reports so that comparisons can be drawn between the 

information contained in these reports and the information in the on-site records, 

especially if during the pre-inspection review the inspector identifies any inconsistencies. 

Alternatively, the inspector may copy the appropriate records and perform this comparison 

off-site. If any equipment is complying by an option of the regulations that requires annual 

testing, then it is advisable to bring semiannual reports which contain test results to check 

4-11
for consistency with the complete test reports. The records for leaking pumps, 

compressors, and valves should be compared with the numbers in the last several 

semiannual reports. Any inconsistencies between the reports and records should be noted. 

The inspector should then review the monitoring data to ascertain if the control 

device is being operated according to its design. The records must also contain design 

specifications, instrumentation diagrams, etc. so that this comparison can be drawn. The 

records are to contain a log of periods when the closed-vent systems and control devices 

are not operated in accordance with the design specifications. The duration and frequency 

of noncompliance episodes should be noted. The inspector should compare his findings 

regarding such periods (based on a review of the monitoring data) with the instances 

recorded in the log. Any inconsistencies should be noted in the inspection notebook. 

The test data pertaining to no detectable emissions equipment or valves complying 

with percentage of valves leaking provision that was reported should be compared with 

the test information contained in the records. Again, any inconsistencies should be noted. 

A test for a process unit complying with the percent leakage that indicates greater than 

two percent leakers is a violation. Any instance where such a test was conducted and not 

reported should be noted and evaluated as a possible inconsistency or a violation. 

4.1.3 Post-Inspection Review and Reports 

4.1.3.1 Post-Inspection Review 

The post-inspection process should begin by reviewing the applicability 

determination to ensure that all questions about the facility as a whole and all individual 

process units have been fully answered. The equipment listings should also be reviewed. 

There are two fundamental questions that an inspector should consider during this 

post-inspection data sorting. 

• Is the recordkeeping system adequate to track monitoring, leaks, and 

repairs? 

• Are the monitoring staff, equipment, and procedures adequate? 

The answers to these questions and rationale for these answers should be contained in the 

inspection report. If the response to either of these is no, suggestions should be made to 

proper plant personnel to address correction of the existing problems. 

4.1.3.2 Post-Inspection Reports 

4-12
Upon completion of the walk-through inspection, the inspector should begin 

preparing the inspection report while all the events of the inspection are still fresh in his or 

her mind. The inspector should prepare the report before conducting another leak 

detection inspection. When two or more inspections are done at one time, it becomes 

difficult to mentally separate one from another. The facility data contained in the initial 

report, the semiannual reports, as well as results of the facility record review and the 

inspection, constitute the information available to the inspector to evaluate compliance 

with the regulations. Additional information, elaboration or clarification may come from 

the inspector's field notebook. If the inspector feels that it is needed, letters may be issued 

or phone calls made requesting additional information. The instance may occur where a 

return visit to the plant is necessary. These follow-up type inspections should be 

abbreviated in nature and focus on the unanswered questions or problem areas. 

The next phase of the post-inspection process is to write the inspection report. 

The report organizes and correlates all evidence gathered during the inspection into a 

concise and useable format. The report serves to record the procedures used in gathering 

data and gives factual observations and evaluations drawn in determining facility 

compliance. The inspector's report will also serve as part of the evidence for any 

enforcement proceeding or compliance-related follow-up activities. 

The inspection results should be organized in a comprehensive, objective and 

accurate report. The recommended report elements are listed below: 

• Introduction 

• Compliance Status for Regulated Equipment 

• Evaluation of Observed Program 

• Data 

• Summary 

4.1.4 Preparation for Subsequent Inspections 

After completing the report, the inspector should prepare for the next inspection 

while the facility's processes are still fresh in his or her mind. This can be accomplished by 

preparing a list of items to be checked and information to be reviewed or gathered during 

the next inspection. 

There are several suggestions to be considered for subsequent inspections at a 

facility. The pre-inspection preparation should basically be the same for each inspection. 

The inspector should review all the information contained in the facility's file including the 

initial and semiannual reports. The semiannual reports that have been submitted since the 

last inspection should be reviewed most carefully. The past inspection reports should also 

be reviewed. If any items were noted in these reports which required action by the facility, 

then the semiannual reports should be examined with these specific areas in mind. There 

4-13
also are items to consider regarding the on-site inspection. Due to the large number of 

records that are required, it may be impossible to review all records on each visit. If this is 

the case, it is a good idea to spot-check a different portion of the records during each 

inspection. It is also suggested that the inspector check a different area of the plant by 

general walk-through and equipment spot-checks in an effort to eventually cover the entire 

affected facility. 

4.2 DIRECT MONITORING OF COMPONENTS 

The use of monitoring equipment by an inspector introduces an added level of 

complexity to the inspection process and may produce unsatisfactory results if the direct 

monitoring is not carefully planned. On the other hand, some detailed inspection data 

suggest that actual leak rates are often much higher than what is reported by the facilities, 

and some local agencies are convinced that a comprehensive direct monitoring strategy is 

necessary for effective enforcement of the equipment leak rules. However, the use of 

direct monitoring by inspectors does not necessarily guarantee an effective regulatory 

program in and of itself. 

In recent years, the National Enforcement Inspection Center (NEIC) of U.S. EPA 

has conducted a number of comprehensive sampling inspections of facilities subject to 40 

CFR 60, Subpart GGG, NSPS for petroleum refineries. These inspections included some 

facilities at which direct monitoring had been included as part of the local agency's 

inspection procedures. A typical NEIC inspection involved two or three inspectors 

conducting direct monitoring of eight or ten process areas. Plant personnel or their 

contractors accompanied the inspectors and conducted their own monitoring, employing 

the same methodology used by the EPA inspectors (Method 21). In all cases, the NEIC 

inspections measured leak rates at a majority of process areas that were substantially 

higher than leak rates currently being reported by the facilities. A typical inspection of ten 

process areas would find seven or more process areas with leak rates of three to five times 

the reported rates. In all cases but one, leak rates found by the plant personnel 

accompanying the inspection agreed with the findings of the inspectors. 

These inspections suggest that the primary problem is the monitoring methodology 

employed by the facilities or their contractors. Although ostensibly following Method 21 

procedures, the monitoring personnel appear to be performing cursory examinations in an 

attempt to complete as many inspections as possible within an allotted period of time, 

resulting in a chronic under-reporting of leak rates. 

These inspections also illustrate some of the difficulties associated with evaluating 

compliance with the equipment leak rules. If a facility is conducting the required 

monitoring, performing repairs on schedule, and complying with all of the recordkeeping 

and reporting requirements, it can be extremely difficult to demonstrate that the facility is 

4-14
not achieving the emission reductions expected from the reported level of performance. 

The inspector can only periodically observe performance of the monitoring personnel and 

can at best only develop circumstantial evidence of inconsistencies between routine and 

observed monitoring practices. 

The use of direct monitoring within the context of an agency inspection program 

needs to address this issue of verifying that the monitoring and testing procedures utilized 

by the plant are in full compliance with the Method 21 sampling methodology. To 

accomplish this, an inspector could monitor a representative sample of equipment within a 

process area and compare the results with the history of leak checks for that process area 

conducted by the plant. A large discrepancy between the inspector's findings and the 

plant's records would indicate that the monitoring procedures of the plant need to be 

improved. 

Another means of evaluating the monitoring procedures of plant personnel is to 

have them monitor all of the components in a specific area of a process unit, while the 

inspector follows and monitors the identical equipment. Alternatively, the inspector could 

accompany the plant personnel and monitor each piece of equipment concurrently, so that 

both operators obtain the same reading. In the first case, discrepancies in the results of the 

two evaluations would indicate a need for improved monitoring technique, while the 

second scenario allows the plant personnel to directly perform the monitoring method as 

practiced and approved by the Agency. 

4.2.1 Process Area Inspection 

Evaluating the monitoring technique of plant personnel is useful on an occasional 

basis, but conducting inspections of a representative sample of equipment within a process 

area is probably preferable as a long-term inspection practice. It directly addresses the 

performance of regulated equipment at a facility and can be more consistently replicated as 

an inspection procedure. Plant personnel would also have the opportunity to accompany 

the inspector with their own monitoring equipment without interfering with the inspection 

procedure. 

Determining what constitutes a representative sample of equipment within a 

process area is an issue of both numbers and accessibility. Equipment that is not classified 

as difficult or unsafe to monitor, but which requires some exertion to reach (e.g., climbing 

towers) should be systematically included in the inspector's sampling pattern. Equipment 

such as pumps and compressors, which are normally present in small numbers within a 

process area, can all be sampled. Valves, normally present in very large numbers within a 

process area, need to be systematically sampled. Other equipment, including connectors, 

pressure relief devices, and equipment subject to no detectable emission limits, can be 

spot-checked during the inspection. 

4-15
As a general rule of thumb, 200 to 300 valves can be inspected within a half day of 

direct monitoring and are usually a sufficient number to constitute a representative sample. 

Very large process areas (i.e., more than 1,000 valves) may require a larger sample. A 

purely random sampling of valves is often infeasible and is usually not necessary so long as 

other steps are taken to maintain representativeness. For example, if a process area has 

four reactor columns which require climbing to access equipment, select one or two 

columns and monitor all valves on those selected. 

Usually, one or two cohesive subsets of a large process area can be identified and 

sampled as a representative sample of that area. Often, the facility will have an established 

"start-to-finish" route to be used by its own monitoring personnel or subcontractors. 

Using a process flow diagram, it may be possible to divide the route into three or four 

sections and then select any one section as the representative sample for that area. Any 

equipment type such as pumps, reactor columns, surge control vessels, etc. that are 

concentrated in a specific area should be added to the inspection. Depending on the 

number involved, all or a portion of these units (as well as valves and other connectors 

associated with the units) can be sampled. 

To be most effective, direct monitoring needs to be repeated. An ideal practice 

might be to test each process area at a regulated facility once per year. The specific 

process area to be tested on any given day would be unannounced. If annual testing of all 

process areas cannot be achieved, the selection of process areas to be tested should be 

guided by the inspector's on-site observations and evaluation of the facility’s records and 

reports. Additionally, certain process areas can be expected to leak more often than 

others and should therefore be inspected more frequently. These areas include those 

processes containing more volatile materials and processes operating at elevated 

temperatures or pressures. 

4.2.2 Inspection Preparation 

Preparing for and conducting an inspection that includes direct monitoring of a 

process area is very similar to the procedures for a walk-through inspection described 

earlier in this section. The principal difference is that performance of the monitoring by 

the inspector replaces the observation of monitoring by facility personnel. Other 

inspection activities, including preview of reports, on-site observations of regulated 

equipment, interviews with plant personnel, and on-site inspection of records remain 

virtually unchanged. Direct monitoring activities may increase an inspector’s risk of 

exposure and the adequacy of safety planning steps should be reviewed. 

Several steps need to be added to the preparation stage to ensure a successful 

inspection. These include equipment maintenance, supplementary supplies, and planning 

the monitoring approach. 

4-16
Prior to each inspection, the monitoring instruments and supporting equipment 

should be inspected to confirm that everything is in good working order and will be 

available on the dates needed. 

The next step in the pre-check procedure is to confirm that the sampling 

instrument is properly calibrated. This includes checking that the monthly calibration 

precision test has been conducted and scheduling a daily calibration test for the inspection 

date. If a calibration test is to be performed in the field, confirm that disposable cylinders 

of certified gas mixtures in the appropriate concentrations will be available. 

Finally, check the condition of the analyzer backpack. All analyzers should be 

outfitted so that the instrument can be carried on the inspector's back. Additionally, the 

pack straps should be equipped with clips for the hand-held probe and the inspector's 

clipboard. This allows both hands to be free for climbing ladders. Use of a backpack will 

greatly reduce fatigue, and the probe can also be clipped to a strap when the inspector is 

writing in the clipboard. 

Selection of the specific process area or areas to be tested should be accomplished 

during the inspection preparation. This may be done as a result of a preliminary review of 

reports and records, notes from previous inspections, or an annual schedule. Process area 

schematics, leak monitoring and repair records, and information about process materials 

(type of service, heated or pressurized processes, volatility of process materials) can be 

used to make such determinations. These materials should be requested in advance from 

the facility. When the inspection is scheduled with the facility, the inspector should 

request that the most recent records for four or five process areas (including the one to be 

directly monitored) be available at the beginning of the inspection. This will allow the 

inspector to review the most up-to-date information on the process area immediately 

before the inspection. 

4-17
4.2.3 On-Site Inspection Procedures 

During the pre-inspection meeting, identify the specific process area(s) you plan to 

inspect and monitor and review the most recent records from those processes. Also, 

request to see a copy of the permit and check to see if the permit is current and valid. 

Compare your agency's current equipment list with the source's equipment list. Check 

existing permit conditions and ask if any changes have been made to the operation which 

are not reflected in the permit. 

Immediately prior to entering the process area, warm up your analyzer instrument, 

check that all components are operating properly, and perform a span check with the 

appropriate calibration gas. Upon entering the process area, ask the production personnel 

if there are any leaking components and when they were found leaking and tagged. 

Compare any reported leakers with the most recent records for that area. While 

conducting the monitoring inspection, observe tags on leaking components to ensure that 

they are properly dated and that the allowed time period for repair has not expired. 

While conducting the monitoring inspection, use your senses of sight, smell, and 

hearing to survey an area for leaks and to help you zero in on leaking components. As 

you enter an area and proceed from component to component, note any suspect odors and 

watch for any increases in background concentrations on your analyzer gauge. Look for 

any distortion emanating from the equipment similar to the distortion seen from infrared 

radiation near the ground or on a roof on a hot day. Also, look for such distortions in the 

shadow of the equipment. If background noises are not excessive, you may also detect 

leaks by hearing them. Investigate the source of any unexplained hissing sounds. 

Caution: Your risk of an exposure that exceeds acceptable levels can increase 

significantly as you zero in on leaking components. Be certain that all appropriate 

safety gear is donned before proceeding with your investigation. 

Always look for liquid leaks from components in the form of drips or spray mist. 

Investigate any stains which may be the result of recent evaporation of such leakage. If 

process or sealing fluids are present at valve stems, pump shafts, or connection points, 

look for bubbles which may indicate a leak. 

When using the analyzer to check each piece of equipment for a leak, move the 

probe slowly along the interface where a leak may be likely, holding the probe tip as close 

to the interface as possible. Look for blips in the meter reading, which may indicate that 

you recently passed over a leak. Remember that there is a response time lag (usually less 

than five or ten seconds) between the time a VOC is sucked into the probe and the time 

that a meter indication is observed. When a blip is observed, slowly retrace your sampling 

route until you find the point at the interface where the leak is highest. 

4-18
The leak rate is measured by finding the highest concentration of the leak. At the 

interface where the leak is highest, vary the angle of the probe to maximize the 

concentration. If possible, block any wind or draft from the area you are checking. Read 

and record the maximum concentration that you can maintain for several seconds, not just 

the peak of a spike. If the leak is intermittent or pulsing, note the maximum 

concentrations across several cycles and record the maximum of these readings. In the 

case of gross leaks (e.g., 50,000 ppp or more), attempting to read the maximum 

concentration following this procedure may lead to flame-out or saturation of the analyzer. 

Addition of dilution air to the probe intake may be necessary to obtain an accurate 

reading. Alternatively, the inspector may record the highest reading obtainable without 

risking damage to the analyzer and note any supplementary information (odors, etc.) 

associated with the leak. 

Within the portion of a process area selected for direct monitoring, certain 

components are more likely to leak than others, and these components should be carefully 

examined. Flow control valves, which are operated more frequently than other valves, are 

correspondingly more likely to leak. There are often valves and connectors located near 

pumps and compressors that are subjected to vibrations and pressure surges. A pump that 

is not running is more likely to leak at the shaft seal than one which is operating. Gauges 

and meters that have been repositioned by plant personnel are more likely to leak as a 

result of such movement. Finally, any equipment that has been worked on or recently 

installed is more likely to leak. Visual cues (tool marks, new looking or cleaner 

components) as well as the facility's monitoring and repair records will help you identify 

such components. 

It may not be necessary to record every component you examine, especially if you 

can use a process diagram to document the areas inspected. Ask the plant personnel who 

accompany you during the inspection to keep a running tally of the number and type of 

each component inspected. When a leak is detected, record the leak rate and the ID for 

the leaking component. Plant personnel should tag each leaking component. If plant 

personnel make an initial attempt to repair the component, try to reinspect these 

components to confirm the results of the initial repair attempt. It may be possible to do 

this after monitoring of the selected area is completed or at the end of the day. If 

personnel initiate repair attempts while you are conducting the monitoring inspection, do 

not slow down your own inspection schedule by waiting to monitor repairs. Come back 

after completing your monitoring schedule. 

Detailed inspection procedures for valves, pumps, compressors, pressure relief 

devices, connectors, and other equipment have been discussed earlier in this chapter. 

While conducting the inspections, remember to look for grease or other materials that 

could plug the probe and continually check the probe tip for any obstructions. Also, use 

caution when inspecting any moving equipment. Do not touch the surface of any rotating 

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or reciprocating shaft with the probe tip of your analyzer. Use a short piece of plastic or 

tygon tubing at the probe tip as an extra means of protection. 

4.2.4 Post-Inspection Interview 

Include a discussion of the findings from your monitoring inspection in the postinspection interview with plant personnel. Address any areas where the monitoring results 

may result in a notice of violation, such as leaks from equipment designated for no 

detectable emissions. If the monitoring results indicate a significant discrepancy with leak 

rates reported by the facility, discuss this issue and elicit comments from the plant 

personnel regarding specific actions to be taken to address the problem. 

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CHAPTER 5 

RECOMMENDED INSPECTION TECHNIQUES AND PROCEDURES 

5.1 INSPECTION PROGRAM DEVELOPMENT 

Chapter four briefly referred to the fact that the emphasis of equipment leak 

inspections will vary in response to a variety of factors. One important factor is the state 

of LDAR program development at a new facility or at a facility newly subject to a new 

rule. Initial inspections at such facilities would focus on applicability, appropriate 

classification of equipment, and documentation of exemptions. Later inspections would 

focus more heavily on inspection of monitoring practices, recordkeeping, and repair 

procedures, and addressing the correction of identified deficiencies. Assuming the LDAR 

program at the regulated facility matures and stabilizes, on-going inspections may evolve 

into a more-or-less routine pattern of compliance oversight. 

However, even within the context of inspections at a facility with an established 

LDAR program, the emphasis of individual inspections will vary. There may be one or 

two annual inspections that address the facility as a whole in addition to periodic 

inspections that look more closely at individual process areas. Intermittent events, such as 

start-up following a process shutdown or the employment of new monitoring personnel at 

the facility, may become the primary emphasis of individual inspections. Finally, the 

experience level of the inspector may be a factor in the selection of inspection emphasis. 

Implementation of the HON equipment leak provisions provides a convenient 

means of illustrating such an evolution of inspection emphasis. As the rule was 

implemented, many chemical facilities found themselves subject to equipment leak 

regulations for the first time. For those facilities already subject to NSPS or NESHAP 

regulations, the HON was likely to introduce an expansion of the number of regulated 

process areas as well as more extensive recordkeeping requirements and more stringent 

leak standards. Such facilities may have found that current monitoring and recordkeeping 

practices were inadequate, or even inappropriate, for the demands of the regulations and 

the needs of the facility. Those changes may have resulted in an expanded level of 

inspection activity for the regulatory agency as well as a need to adjust the inspection 

emphasis in step with development of the LDAR programs at the regulated facilities. 

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At the outset of implementation of new LDAR requirements for a facility, the first 

few inspections would focus primarily on applicability issues while developing familiarity 

with the plant's initial approaches to monitoring, recordkeeping, and equipment repair. 

Finding and reconciling any misclassification or oversight with respect to regulatory 

applicability during the initial phase could avoid more serious complications at a later 

stage. An inspector addressing this issue could consult with personnel in the agency who 

have developed the facility's permits, study process flows and material balances of the 

facility, and review the documentation and justification for those processes which have 

been classified as qualifying for various exemptions. At this time, the inspector should 

also look at equipment classified as "difficult to monitor" or "unsafe to monitor" to 

confirm that such equipment meets the applicable requirements. 

Once the issue of applicability has been adequately resolved, the inspector can 

begin to concentrate on direct observation of the facility's monitoring program and 

conduct visual inspections of individual process areas. While observing monitoring 

activities, the inspector may devote one or two site visits to conducting side-by-side 

monitoring with the facility's personnel. This would afford an opportunity to identify and 

address any problems with monitoring techniques at the facility. In the case of process 

area site visits, the inspector can interview operating personnel so as to gain insight into 

how well they understand their role in developing compliance with the equipment leak 

regulations. The inspector should also address issues such as proper tagging of leaking 

equipment, performance of repairs within the allotted time, follow-up monitoring of 

repaired equipment, visual inspections, and recordkeeping practices to document these 

activities. The inspector should also become familiar with closed-vent control devices at 

the facility and the equipment served by such devices. 

After several rounds of monitoring have been completed and the first one or two 

periodic reports submitted, the inspector can relate his or her developed familiarity with 

the facility to the information in these records and reports. The inspector will be able to 

identify those process areas and equipment types that are exhibiting higher than average 

leak rates and may even be able to identify specific pieces of equipment as "chronic 

leakers." 

The next phase of inspection activities, beginning perhaps midway through the 

second year of regulations, would begin to incorporate direct monitoring of representative 

portions of selected process areas. Once again, developed familiarity with the facility will 

aid the inspector in selection of appropriate areas to be monitored. Direct monitoring 

inspections can become an important part of inspection procedures over the next several 

years, along with periodic observational inspections or walk-throughs of larger portions of 

the facility. 

Maintaining consistent documentation in the form of inspection reports and 

associated notes will help to develop a consistent background file on the facility. This can 

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be especially important as experienced inspectors are replaced by new personnel. Ideally, 

one or two inspectors should be continuously assigned to the same facility or group of 

facilities and should be responsible for the full range of air related permits and emission 

control programs at those facilities. This will help to reinforce a fuller understanding of 

the facilities and will also broaden the range of regulatory expertise among the individual 

inspectors. Additionally, if possible, a new inspector should accompany a more 

experienced individual on several inspections for training. Finally, whenever feasible, 

experienced inspectors should accompany each other on inspections of their respective 

facilities. This will help to expand the inspector's perspective by exposing them to 

equipment leak programs at other facilities and will also help to reinforce consistent 

monitoring and inspection techniques among the inspection staff. 

A final, optional phase of inspection activities would be to conduct comprehensive 

monitoring inspections of individual facilities. This would involve two or three inspectors 

visiting a facility for several days to conduct complete monitoring of selected process 

areas and/or representative portions of larger process areas. Such inspections could be 

patterned after the in-depth inspections of the NEIC. Facility personnel would accompany 

the inspectors and conduct side-by-side monitoring of selected process areas. These 

comprehensive monitoring inspections could accomplish three purposes: (1) evaluate and 

compare the extent to which the facilities are accomplishing the emission reduction 

objectives of the regulations, (2) evaluate the effectiveness of the agency's inspection 

program, and (3) provide a basis for documenting noncompliance in the form of underreporting of leak rates at individual facilities. As a long-term program, comprehensive 

monitoring inspections could be performed on all facilities or a subset of facilities within 

an agency's jurisdiction on a cycle of once every four or five years. Additionally, 

comprehensive inspections could be performed at individual facilities whenever such 

action is necessary. 

5.2 WORKING WITH REGULATED FACILITIES 

Over the long term, a successful inspection and regulatory enforcement program 

for the equipment leak regulations is more likely to succeed if the inspector can develop a 

cooperative working relationship with the regulated facilities. Such a relationship will 

make it easier for the inspector to obtain information about the facility in the form of 

reformatted or supplemental reports and other information not specifically identified by the 

recordkeeping requirements. The inspector may also find it easier to elicit verbal 

information about planned changes or developments within the facility which can be useful 

to the planning effort for future inspections. In exchange, the inspector may be able to 

assist the regulated facility by providing information or assistance helpful to the facility's 

development of a successful equipment leak program. Such a relationship can therefore 

improve the probability that enforcement of the equipment leak regulations will contribute 

to effective and long-term reductions of this class of emissions. 

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The issue of component monitoring technique is a particularly important area in 

which the inspector can potentially contribute assistance. Facility personnel or contractors 

responsible for monitoring may feel inclined to complete the monitoring of as many 

components as possible within a limited amount of time. This emphasis on speed and 

efficiency may result in a decline in monitoring technique, with personnel moving their 

analyzers too quickly over the equipment or not holding the probe tip close enough to 

those points where leaks are likely to occur. As previously discussed, the inspector can 

review and critique the monitoring technique of plant personnel or engage in side-by-side 

monitoring with the personnel. This creates an opportunity for the inspector to 

demonstrate correct monitoring techniques and can improve the probability that reported 

leak rates accurately reflect conditions at the facility. 

Collaboration in the area of monitoring technique can be taken one step further by 

making agency training available to monitoring personnel from the regulated facilities. 

Shared training further reinforces the objective of getting the facilities to practice 

appropriate monitoring techniques and may also contribute to cost savings for both the 

agency and the facilities with respect to training costs. For example, the South Coast Air 

Quality Management District (SCAQMD) has found shared training to be a successful 

approach. The SCAQMD is planning to expand their program to include certification of 

facility monitoring personnel. 

As an inspector develops experience with equipment leak programs and learns 

more about how other facilities are developing their programs, the inspector may be able 

to offer additional assistance or advice in a number of areas. An inspector can develop 

such experience from accompanying other inspectors to other facilities, and through longterm observation of different approaches within facilities assigned to the inspector. If one 

or two facilities within an agency's jurisdiction are achieving exceptional success with their 

leak minimization programs, an inspector can inform other facilities of such 

accomplishments and encourage information sharing between the facilities. An inspector 

may also be aware of additional potential resources, such as trade associations, that may 

be a source of help to a facility. 

Some of the approaches used by successful facilities include in-plant oversight of 

monitoring procedures, use of internal leak standards, innovative component tracking 

systems, use of advanced repair systems and materials, and installation of new equipment 

with improved leak minimization performance. 

In-plant oversight of monitoring involves the application of quality assurance 

techniques to the equipment monitoring and leak reporting activities. Some facilities that 

employ subcontractors have found it advantageous to obtain analyzer instruments and 

train one or two plant personnel to provide oversight and backup to the contract 

monitoring service. By developing an in-house monitoring capability, the facility is better 

able to identify and correct any deficiencies in the contractor’s performance. As a backup 

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resource, the in-house personnel are most valuable as a means of assuring appropriate 

follow-up monitoring and reporting of repaired equipment. 

Although most contract monitoring services provide a database and recordkeeping 

system as part of their package, some facilities prefer to develop an internal system. This 

allows for faster acquisition of reports, enables report formats to be modified, addresses 

some issues of confidentiality, and creates the opportunity to incorporate the monitoring 

and recordkeeping systems in the development of additional program elements. 

Facilities that perform their own monitoring cite a number of factors which 

reinforce their commitment to this approach. Having plant-wide in-house monitoring 

capabilities permits the establishment and maintenance of higher performance standards 

and allows for greater flexibility in the utilization of monitoring resources. This flexibility 

can be applied to leak testing equipment during process repair and maintenance activities, 

during startup after a process shutdown, and for spot-checking suspect equipment without 

waiting for the routine monitoring schedule. 

Internal plant standards refer to a potentially broad range of activities designed to 

ensure compliance by doing more than the minimum requirements of the regulations. 

Some plants will repair equipment before applicable leak rate definitions are exceeded 

(e.g., conduct an initial repair procedure on any equipment leaking at 5,000 ppm or more 

when the leak definition is 10,000 ppm) Other strategies include supplemental monitoring 

as described previously, replacement of equipment which continues to leak after two or 

more attempts at repair, and repair of equipment which could be classified as nonrepairable. In a related approach, many facilities have incorporated environmental 

compliance, waste minimization, pollution prevention, and similar goals within the context 

of total quality management programs or other production quality initiatives. 

Component tracking addresses the utilization of repetitive monitoring data to 

evaluate the long-term performance of equipment. This can include the identification of 

equipment which leaks chronically or performance comparisons of alternative components 

within a process area. The increased sophistication and flexibility of internalized databases 

and recordkeeping systems lends support to the utilization of component tracking 

strategies. 

Equipment leak regulations have been in effect at some facilities for a number of 

years. Efforts to minimize equipment leaks have contributed to advances in repair 

techniques and materials and to development of new equipment with improved leak 

minimization performance. Improved repair techniques have greatly expanded the number 

and types of equipment which can be repaired in place, without a process shutdown. 

Improved component materials such as specialty gaskets can improve the performance and 

extend the life of existing equipment. Finally, the design of new processes or 

5-5
reconstruction of existing process areas can incorporate leak minimization efforts by 

reducing the number of valves, flanges, and other connectors within the process system. 

The leak standards and other specified control strategies within the HON are a 

reflection of the achievable standards resulting from the improved equipment, repair 

techniques, and information management strategies summarized above. Additionally, the 

QIP provisions of the HON are based on leak minimization programs that have worked 

for other facilities in the past. Although not formally required until Phase III, an inspector 

might suggest that facilities implement QIP plans or an in-house equivalent early on as a 

means of improving their opportunities to meet compliance with the standard. 

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