MEMORANDUM

Date: September 16, 2013

TO: Docket No. EPA-HQ-OAR-2012-0510: National Emissions Standards for 

Hazardous Air Pollutants for Flexible Polyurethane Foam Production

FROM: Kaye Whitfield, EPA/OAQPS/SPPD

SUBJECT: Technology Review and Cost Impacts for the Proposed Amendments to the 

Flexible Polyurethane Foam Production Source Category National Emissions 

Standards for Hazardous Air Pollutants (40 CFR part 63, subpart III)

1.0 INTRODUCTION

Section 112 of the Clean Air Act (CAA) requires the U.S. Environmental Protection Agency 

(EPA) to establish technology-based standards for listed source categories. These technologybased standards are often referred to as maximum achievable control technology (MACT) 

standards. The Flexible Polyurethane Foam (FPUF) Production MACT standard (40 CFR part 

63, subpart III) applies to major sources and regulates HAP emissions from three separate types 

of foam production operations: slabstock flexible polyurethane foam (i.e., slabstock foam), 

molded flexible polyurethane foam (i.e., molded foam), and rebond foam. The FPUF Production 

MACT standard includes requirements for foam production lines, storage vessels, transfer 

pumps, equipment leaks, and hazardous air pollutant (HAP) use restrictions and prohibitions.

Section 112 also contains provisions requiring the EPA to periodically revisit these standards. 

Specifically, section 112(d)(6) states:

(6) REVIEW AND REVISION. – The Administrator shall review, and revise as 

necessary (taking into account developments in practices, processes, and control 

technologies), emissions standards promulgated under this section no less often than 

every 8 years.

To comply with this CAA requirement, the EPA conducted a technology review for the FPUF

Production MACT standard for major sources. For the purposes of reviewing a MACT standard, 

the EPA considers a “development” in practices, processes, and control technologies to be:

• Any add-on control technology or other equipment that was not identified and considered 

during development of the original MACT standards.
2

• Any improvements in add-on control technology or other equipment (that were identified 

and considered during development of the original MACT standards) that could result in 

significant additional emissions reduction.

• Any work practice or operational procedure that was not identified or considered during 

development of the original MACT standards.

• Any process change or pollution prevention alternative that could be broadly applied to 

the industry and that was not identified or considered during development of the original 

MACT standards.

• Any significant changes in the cost (including cost effectiveness) of applying controls 

(including controls the EPA considered during the development of the original MACT 

standards).

Section 2 of this memorandum presents a background of the FPUF Production source category

and Section 3 presents a summary of the sources of data that were used to conduct the 

technology review. Sections 4 through 6 present the summaries of the technology reviews related 

to HAP ABA use at slabstock foam production facilities, the slabstock foam production line, 

diisocyanate storage vessels and diisocyanate equipment leaks.

2.0 DESCRIPTION OF THE SOURCE CATEGORY AND MACT STANDARD

The flexible polyurethane foam industry encompasses three separate types of foam production 

operations: slabstock flexible polyurethane foam (i.e., slabstock foam), molded flexible 

polyurethane foam (i.e., molded foam), and rebond foam. Slabstock foam is produced in large 

continuous buns that are then cut into the desired size and shape (fabricated). Slabstock foam is 

used in furniture, bedding, packaging, and carpet cushioning. Molded foam is produced by 

"shooting" the foam mixture into a mold of the desired shape and size. The major use of molded 

foam, by weight, is in automobile interiors, but is used in many other applications such as

packaging, novelty applications, and medical supplies. Rebond foam is made from scrap foam 

that is converted into a material primarily used for carpet underlay. 

The FPUF Production MACT standards were originally proposed in the Federal Register on 

December 27, 1996 (61 FR 68418) and promulgated on October 7, 1998 (63 FR 53980). The 

FPUF Production MACT standards for flexible polyurethane foam production contain 

requirements specific to the type of foam produced. For slabstock foam production, the FPUF 

Production MACT standards include diisocyanate and HAP auxiliary blowing agents (ABA)

emissions reduction requirements. For diisocyanate emissions from slabstock foam production, 

the FPUF Production MACT standards have requirements for storage vessels, transfer pumps 

and equipment leaks. Standards for HAP ABA emissions at slabstock facilities include 

requirements for storage vessels, equipment leaks, the production line, and equipment cleaning. 

For molded and rebond foam production, the FPUF Production MACT standards include HAP 

use restrictions. The requirements of the standards are the same for both new and existing 

sources.

For diisocyanate emissions from slabstock foam production, the FPUF Production MACT

standards have requirements for storage vessels, transfer pumps and equipment leaks. The 

storage vessels requirements include the installation of either a vapor recovery system or a 

carbon adsorption system. Transfer pumps are required to be either sealless pumps or pumps 
3

submerged in a neutral oil, and submerged pumps must be visually inspected periodically for 

leaks. Other components in diisocyanate service must be repaired when a leak is detected. 

Standards for HAP ABA emissions at slabstock facilities include requirements for storage 

vessels, equipment leaks, the production line, and equipment cleaning. For HAP ABA storage 

vessels, the FPUF Production MACT standards require installation of either a vapor recovery 

system, or a carbon adsorption system. For HAP ABA equipment leaks, the FPUF Production

MACT standards require a leak detection and repair (LDAR) program. For the slabstock 

production line, the amount of HAP ABA that can be used is restricted, calculated via a chart and 

a formula and based on production levels and the types of foam produced. HAP ABA use is only 

allowed for production of certain low-density grades of foam. The use of HAP or HAP-based 

products for equipment cleaning in slabstock foam production is prohibited. The rule also 

includes a “source-wide” HAP ABA alternative emission limit that allows slabstock facilities to 

comply by limiting the total amount of HAP ABA used at the facility (rather than by complying 

with the emission point-specific requirements). The “source-wide” HAP ABA usage limit is 

calculated in the same manner as the emission-point specific limit.

For molded foam and rebond foam production, the FPUF Production MACT standards prohibit 

the use of any HAP-based product as an equipment cleaner or as a mold release agent (with an 

exception for diisocyanates used for startup and maintenance mix head flush on molded foam 

lines, which must be contained in a closed-loop system). 

Various other practices, processes, and control technologies were considered in the development 

of the MACT standards, which are summarized below in Table 1. Additional information on 

these control techniques can be found in the Background Information and Supplementary 

Information Documents used to support the FPUF Production MACT standard rulemaking.1

 

1 Hazardous Air Pollutant Emissions from the Production of Flexible Polyurethane Foam Basis and Purpose 

Document for Proposed Standards, Emission Standards Division U.S. Environmental Protection Agency, September 

1996.
4

Table 1. Summary of Practices, Processes, and Control Technologies Identified and 

Considered During Flexible Polyurethane Foam Production MACT Standards 

Development

Source Category/

Emission Source Practices, Processes, and Control Technologies

Slabstock – Storage Vapor balancing system, carbon adsorption

Slabstock – Equipment Leaks LDAR program, equipment modification (leakless pumps)

Slabstock – Equipment 

Cleaning

Steam cleaning, material substitution (non-HAP cleaners)

Slabstock – Foam Repair Hot-melt adhesives, water-based adhesives, hydrofuse 

adhesive

Slabstock – Foam Tunnel Non-HAP ABA (Acetone or CO2), foaming in controlled 

environment, forced cooling, chemical modification, 

carbon adsorption

Molded – Mixhead Flush Non-HAP flush, high pressure mixheads, self-cleaning 

mixheads, solvent recovery

Molded – Mold Release Material substitution (non-HAP mold release agents), 

reduced-VOC solvent agents

Molded – Equipment Cleaning Material substitution (non-HAP cleaners)

Molded – Foam Repair Hot-melt adhesives, water-based adhesives, hydrofuse 

adhesive

Rebond – Mold Release Material substitution (non-HAP mold release agents)

Rebond – Equipment Cleaning Material substitution (non-HAP cleaners)

3.0 SOURCES OF AVAILABLE CONTROL TECHNOLOGY INFORMATION

To identify developments in practices, processes and control technologies since the MACT 

standards were developed, we consulted the following sources of data:

• Contacts with the industry 

• Regulatory analyses performed by the EPA and State regulatory agencies 

• State Regulations 

• The EPA’s RACT/BACT/LAER clearinghouse 
5

3.1 Contact with Industry

Industry trade organizations were consulted several times during the residual risk and technology 

(RTR) review process for FPUF Production. The primary source of industry information was the 

Polyurethane Foam Association (PFA), a trade association representing the slabstock 

polyurethane foam production industry. Information was also collected directly from individual 

foam production companies through a 2011 survey performed under Section 114 of the CAA. 

Information from individual foam production facilities was also gained through site visits 

conducted at four foam production facilities in 2012 and 2013.

Partially through contact with industry representatives, the EPA learned that HAP ABA use has 

been completely discontinued by foam producers in the U.S. This development in industry 

practice for HAP emissions reduction is discussed further in Section 4.1.

3.2 State Regulations

The EPA became aware of some state or local air permitting agencies regulations that apply to 

FPUF Production, specifically, California’s South Coast Air Quality Management District 

(SCAQMD) Rule 1175 for control of emissions from the manufacture of polymeric cellular 

(foam) products. In seeking other state or local regulations that would apply to foam production 

facilities, both a general internet search and a more targeted search directed at states known to 

have multiple foam production facilities (major and non-major sources) was conducted.

SCAQMD Rule 1175 is specific to the manufacture of polymeric cellular (foam) products, but 

addresses VOC emissions with no process specific requirements. It includes a prohibition on the 

use of methylene chloride, the most commonly used HAP ABA, for foam production. However, 

the methylene chloride prohibition went into effect on January 1, 1994, which is before the 

promulgation date of the FPUF Production standards. For this reason, this rule requirement was 

not considered as a development in practice, process, or control technology since the MACT 

standard was developed.

3.3 EPA Analyses

For the FPUF Production source category technology review, the EPA also considered other 

technology reviews the Agency has conducted for source categories that would have similar 

equipment or sources of emissions.

The specific technology reviews considered include those for the Group IV Polymers and Resins 

(P&R IV), Pesticide Active Ingredient Production (PAI), and Polyether Polyols Production 

(PEPO) that were recently conducted for a 2012 proposed RTR action for these source 

categories. These technology reviews were considered due to them being recently completed and 

because these source categories also have storage vessels and equipment leaks as HAP emissions 

sources. Similarly, the technology review analyses for the National Uniform Emission Standards 

for Storage Vessel and Transfer Operations, and Equipment Leaks were also considered in this 

review. Although these analyses are not based directly on operations in the FPUF Production

source category, the EPA believes that they are appropriate to consider with regard to FPUF 
6

Production storage vessels and equipment leaks because the process operations and equipment 

components are similar. Even though these industries may have variations in their process 

operations and the regulated materials used, the emission sources are generally amenable to 

similar methods for control and demonstration of compliance. Thus, it is expected that 

compliance methods that have been determined to be cost effective for control of a specific 

amount of a given regulated material at one of the emission points would generally be cost 

effective for the same regulated material at similar emission points. 

In addition, a review of an EPA survey of control technologies for low concentration organic 

vapor gas streams was conducted, due to the relevance of this information to the emissions from 

storage vessels in the FPUF production industry.

Several potential developments in practices, processes and control technologies were identified 

through these reviews, which are discussed further in Sections 4.3 for storage vessels and 4.4 for 

equipment leaks.

3.4 RACT/BACT/LAER Clearinghouse Database

Under the EPA's New Source Review (NSR) program, if a company is planning to build a new 

plant or modify an existing plant such that criteria air pollution emissions will increase by a 

certain amount, then the company must obtain an NSR permit. The NSR permit is a construction 

permit which generally requires the company to minimize air pollution emissions by changing 

the process to prevent air pollution and/or installing air pollution control equipment. 

The terms "RACT," "BACT," and "LAER" are acronyms for different program requirements 

relevant to the NSR program. RACT, or Reasonably Available Control Technology, is required 

on sources in areas that are not meeting national ambient air quality standards (non-attainment 

areas). BACT, or Best Available Control Technology, is required on new or modified major 

sources in clean areas (attainment areas). LAER, or Lowest Achievable Emission Rate, is 

required on new or modified major sources in non-attainment areas. 

BACT and LAER (and sometimes RACT) are determined on a case-by-case basis, usually by 

State or local permitting agencies. The EPA established the RACT/BACT/LAER Clearinghouse, 

or RBLC, to provide a central data base of air pollution technology information (including past 

BACT and LAER decisions contained in NSR permits) to promote the sharing of information 

among permitting agencies and to aid in future case-by-case determinations. However, data in 

the RBLC are not limited to sources subject to RACT, BACT, and LAER requirements. 

Noteworthy prevention and control technology decisions and information may be included even 

if they are not related to past RACT, BACT, or LAER decisions.2

The RBLC contains over 5,000 air pollution control permit determinations that can help identify 

appropriate technologies to mitigate most air pollutant emission streams. It was designed to help 

permit applicants and reviewers make pollution prevention and control technology decisions for 

 

2 Technology Transfer Network: Clean Air Technology Center. RACT/BACT/LAER Clearinghouse Basic 

Information. http://www.epa.gov/ttn/catc/rblc/htm/welcome_eg.html.
7

stationary air pollution sources, and includes data submitted by several U.S. territories and all 50 

States on over 200 different air pollutants and 1,000 industrial processes.

The RBLC provides several options for searching the permit database on-line to locate 

applicable control technologies. On June 27, 2012, we conducted a search of the RBLC. Our 

search specified VOC- and HAP-emitting processes from North American Industry

Classification System (NAICS) codes 326510 and SIC 3086.3 The search results included the 

following data fields:

• RBLC ID;

• Facility Name, and State;

• Permit Date;

• Process name;

• Throughput;

• Pollutant;

• Control technology; and

• Percent efficiency of control.

The results of the search are presented in Attachment 1. Only one process, practice, or control 

technology was identified for a FPUF facility - for reduction of VOC from application of mold 

release agents at a molded foam facility in Michigan. The existing FPUF Production MACT 

standards prohibit HAP-based mold release agents. Therefore, this exercise did not reveal any 

developments in practices, processes, or control technologies for HAP emissions from FPUF 

production facilities.

4.0 IDENTIFIED DEVELOPMENTS IN PRACTICES, PROCESSES AND 

CONTROL TECHNOLOGIES AND ESTIMATED COST IMPACTS 

Through searches of the data sources described in section 3, several developments in 

practices, process or control technologies were identified for the FPUF Production source 

category. Each of these developments is presented below. An engineering cost analysis was

performed for each of these options to determine whether these developments could costeffectively be put in place for the FPUF Production source category, and the results of these 

analyses are presented below.

4.1 HAP ABA Use in Slabstock Foam Production

During the development of the FPUF Production MACT standard, several technologies were 

identified which allowed reduction or elimination of HAP by switching to non-HAP products for 

equipment cleaning, mixhead flushing, mold releasing, and as ABA. The FPUF Production

MACT standard prohibited the use of HAP products for equipment cleaning, mixhead flushing, 

and mold releasing at molded and rebond foam facilities and prohibited their use for equipment 

cleaning at slabstock foam facilities (except at facilities operating under the provisions for a 

 

3 These NAICS and SIC codes were chosen to be inclusive of facilities in the FPUF source category. They also 

include facilities not in the FPUF source category. 
8

source-wide emission limit for a single HAP ABA). However, based on feedback from industry 

and EPA’s assessment of production at that time, the EPA believed that HAP ABA use was

necessary for production of some grades of foam. Therefore, the FPUF Production MACT

standards significantly limited the use of HAP ABA by slabstock foam producers, but still 

allowed their use in production of certain grades of foam, defined by density and Indentation 

Force Deflection (IFD).

Available data from EPA databases, the 2011 Section 114 survey, and information from State 

and local permitting agencies show that none of the 13 facilities which were identified as being 

subject to the FPUF Production MACT standards are currently using any HAP ABA.4 The 

absence of HAP ABA use was confirmed through discussion with PFA representatives, who 

stated that the few facilities who had continued using HAP ABAs after the promulgation of the 

Foam Production MACT standards and Area Source rules (40 CFR 63 Subparts III and 

OOOOOO) have since discontinued any use of HAP ABAs, and the products now used contain 

no HAP.

5 The complete discontinuation of HAP ABA use by FPUF producers demonstrates that 

foam producers have improved their ability to produce their products using alternatives to HAP 

ABA, which is a practice, process, or control technology that would be considered to be a 

development since the FPUF Production MACT standards were developed.

As no facilities subject to subpart III are currently using any HAP or HAP-based product as an 

ABA, we estimated there will be no cost associated with prohibiting the use of HAP and HAPbased ABAs. Although it is difficult to quantify, we believe there may even be a small cost 

savings at some facilities due to reduced recordkeeping and reporting costs.

4.2 Storage Vessels

During the development of the FPUF Production MACT standards, two compliance options were 

considered for diisocyanate storage vessels: equipping the storage vessels (tanks) with a vapor 

return line from the storage vessel to the truck or rail car during unloading; and equipping with a 

carbon adsorption system which routes displaced vapors through activated carbon. The vapor 

return system was assumed to have a control efficiency of 95 percent.

6 At the time of the MACT 

development, no control options that would result in a higher level of control were reported to be 

in use in the industry or appear to have been considered during the rule development. As noted in 

Section 3.3, for this technology review, a review of a survey of control technologies for lowconcentration organic vapor gas streams performed by the EPA7 was conducted, which identified 

control technologies that could achieve higher control efficiencies than the controls currently 

required by the FPUF Production MACT standards for storage vessels. These technologies are 

regenerative thermal oxidizers (RTO) and recuperative thermal oxidizers (RCO), which are 

capable of achieving 98-percent control efficiency.

 

4 See “Draft Development of the RTR Emissions Dataset for the Flexible Polyurethane Foam Production Source 

Category” in the docket for the FPUF RTR.

5 See “Documentation of Communications with Industry and Regulatory Agency Contacts for the Flexible 

Polyurethane Foam Industry” in the docket for the FPUF RTR.

6 Gasoline Distribution Industry (Stage I) - Background Information Standards. U.S. Environmental Protection 

Agency. Research Triangle Park, North Carolina. Publication No. EPA-453/R-94-002a. January 1994.

7 Survey of Control Technologies for Low Concentration Organic Vapor Gas Streams U.S. Environmental 

Protection Agency. Research Triangle Park, North Carolina. Publication No. EPA-456/R-95-003. May 1995.
9

To determine whether either of these technologies could cost effectively reduce diisocyanate

emissions from storage vessels at FPUF production facilities, a cost analysis was performed. For 

diisocyanate tanks, it is estimated that an additional emission reduction of 0.0026 tpy would be 

associated with an increase from 95 to 98 percent HAP control. The estimated cost per ton of 

emissions reduction would be $124 million and $269 million per ton of HAP using an RTO and 

RCO, respectively. Table 3 summarizes the calculated estimated costs and cost effectiveness 

associated with this increase in control efficiency.

Table 3. Estimated Costs and Cost Effectiveness of Increasing Control Efficiency for 

Slabstock Diisocyanate Storage Tanks

Type of Equipment Current Level of Control Control 

Option 1

Control 

Option 2

Tanks (Uncontrolled)

Vapor 

Balancing/Carbon 

Adsorber

Regenerative 

Thermal 

Oxidation

Recuperative 

Thermal 

Oxidation

Facility Capital Cost1 NA $6,150 $895,281 $537,915

Facility Annual Cost1 NA $1,133 $325,603 $702,280

Facility HAP 

Emissions (tpy)2

0.0867 0.0043 0.0017 0.0017

HAP Reduction from 

Uncontrolled (tpy)

NA 0.08237 0.08497 0.08497

HAP Cost 

Effectiveness ($/Ton)

NA $13,759 $3,832,154 $8,265,426

Incremental HAP Cost 

Effectiveness (vs. Vap. 

Bal.)($/Ton)

$124,245,790 $269,065,995

1 Cost estimates for RTO and RCO are based on methodology set out in the EPA Air Pollution Control Cost 

Manual (Sixth Edition), EPA/452/B-02-001, January 2002 Additional details are included in Attachment 3. 2 Tanks emissions were estimated based on average data from Section 114 survey facilities reporting tank 

emissions. Uncontrolled emissions were estimated by assuming that current reported emissions are 5% of the 

uncontrolled baseline.

4.3 Equipment Leaks

During the development of the FPUF Production MACT, an LDAR program was identified as a 

method for controlling emissions from equipment leaks at slabstock foam facilities for both HAP 

ABA and diisocyanates, and a LDAR program was required for equipment in HAP ABA service.

Numeric leak detection limits were not required for metering pumps, valves, connectors, and 

open-ended lines in diisocyanate service at slabstock foam production facilities. The standards 

require that if “evidence of a leak is found by visual, audible, or any other detection method, it 

shall be repaired as soon as practicable, but not later than 15 calendar days after it is detected.”

As noted in Section 3.3 of this memo, a review of other technology reviews the Agency has 

conducted for source categories that would have similar equipment or sources of emissions was 

conducted, which identified developments in LDAR programs that could reduce emissions 

further than equipment leak control program currently required by the FPUF Production MACT 
10

standards for diisocyanate emissions at slabstock foam production facilities. These developments 

include:

• LDAR programs incorporating the use of EPA Method 21 and revised leak detection 

limits

• Low-leak technology for valves, gaskets, and flanges

• Limits to the number of components allowed to be placed on a delay of repair list

Each of these developments are discussed below in Sections 4.3.1, 4.3.2, and 4.3.3.

4.3.1 LDAR Programs Incorporating EPA Method 21 and Various Leak Detection Limits

As noted in Section 3.3, reviews of the EPA analyses were conducted, including an analysis 

regarding LDAR programs and “low-leak” technologies performed in the development of the 

National Uniform Emission Standards for Storage Vessel and Transfer Operations, and 

Equipment Leaks (40 CFR part 65, subparts H and I). 8 This analysis was developed for the 

purpose of providing consistent requirements for equipment leaks that could be referenced by 

multiple NESHAP subparts, and it incorporates technical improvements based on the EPA’s 

experience with implementation of other subparts, such as the National Emission Standards for 

Petroleum Refineries (40 CFR part 60, subpart CC). As part of this process, the EPA investigated 

current practices and advances in technology and examined the cost effectiveness of applying 

certain technologies for control. For this analysis, the EPA also reviewed the applicability 

determination index database, test reports, title V permit requirements, Office of Enforcement 

and Compliance Assurance experience and recent EPA decisions to identify cost-effective 

technological, monitoring and compliance approaches that would reduce burden across source 

categories.

The EPA also considered the results of the technology reviews for the P&R IV, PAI, and PEPO

source categories that were recently conducted for a 2012 proposed RTR action. In addition, 

comments were received on this proposed RTR action that suggested that the EPA should also 

consider several additional improvements in LDAR programs that the EPA did not identify in the 

proposal technology review. As part of the technology review for the FPUF production source 

category, the EPA considered these suggestions for application to the FPUF Production MACT 

standard. 

Based on these data sources, the implementation of a more stringent LDAR program than 

currently exists for diisocyanate equipment leak emissions, incorporating lower leak detection 

limits than those considered during the FPUF Production MACT development, monitored via 

Method 21 of 40 CFR part 60, appendix A, was identified as a development in a process, 

practice, or control technology that could reduce these emissions from slabstock production 

facilities. Two options for a more stringent LDAR program were considered, based on the EPA 

uniform standards analysis and public comments received on the P&R IV, PAI, and PEPO 

technology review. In addition, analysis of the costs of the basic LDAR program, similar to that 

required by the FPUF Production MACT standard for HAP ABA emissions, was performed to 

 

8 Memorandum from Cindy Hancy, RTI to Jodi Howard, EPA, Analysis of Emission Reduction Techniques for 

Equipment Leaks, December 21, 2011. (EPA-HQ-OAR-2002-0037-0180.) See Attachment 3
11

provide the basic costs of the LDAR program for a starting point from which to gauge the more 

stringent options.

Table 4 shows the options which were considered for implementing a more stringent LDAR 

program incorporating leak detection limits monitored via Method 21 of 40 CFR part 60, 

appendix A. The base LDAR program and the two options are presented below and in Table 4. 

(Base LDAR): Implementation of a leak detection program, with leak detection limits for 

pump seals and valves of 10,000 parts per million (ppm), leak definition for connectors of 

500 ppm; and caps on open-ended lines

(Option 1): Same as base LDAR, but with leak definitions for pump seals lowered to 2,000 

ppm and valves lowered to 500 ppm

(Option 2): Same as Option 1, but with the leak definition for pump seals lowered to 500 

ppm and valves lowered to 100 ppm.

Table 5 details the calculated estimated costs and cost effectiveness associated with each option.

It is estimated that the capital and annual costs of the base LDAR program are approximately 

$32,000 and $28,000 per year, respectively, and the emission reduction would be 0.323 tpy 

relative to the existing equipment leak repair program. The cost effectiveness of the base LDAR 

program is estimated to be $87,000/ton of HAP reduced. 

For the first and second options incorporating reduced leak detection limits, it is estimated that 

the capital and annual costs would be nearly the same as the first option, but with slightly 

increased emission reductions. Estimated emissions reductions of 0.376 tpy and 0.384 tpy are 

associated with options1 and 2, respectively. The cost effectiveness of these options is estimated 

at approximately $75,000/ton of HAP reduced for the first option and $73,000/ton HAP reduced 

for the second option.
Table 4. LDAR Program Options Evaluated for Slabstock Diisocyanate Equipment Leaks

Type of 

Equipment

No. of 

Components

Current Level of 

Control Base LDAR Control Option 2 Control Option 3

Slabstock Diisocyanate Equipment Leaks

Pump Seals 4 Weekly visual 

inspection

Monthly Method 

21 monitoring 

(10,000 ppm leak 

definition)

Lowers leak 

definition to 2,000 

ppm

Lowers leak 

definition to 500 

ppm

Valves 32 Visual, audible, or 

any other 

detection method

Monthly Method 

21 monitoring 

(10,000 ppm leak 

definition)

Lowers leak 

definition to 500 

ppm

Lowers leak 

definition to 100 

ppm

Connectors 40 Visual, audible, or 

any other 

detection method

Monthly Quarterly 

Method 21 

monitoring (500 

ppm leak 

d fi i i )

Same as Option 1 Same as Option 1

Open-Ended 

Lines

12 Visual, audible, or 

any other 

detection method

Cap or 

comparable

Same as Option 1 Same as Option 1
13

Table 5. Estimated Costs and Cost Effectiveness of Enhanced LDAR Programs for Slabstock Diisocyanate Equipment Leaks1

Model Plant Total Capital 

Investment

Incremental 

Capital 

Investment

Annual 

LDAR 

Cost ($/yr)

Incremental 

Annual 

LDAR Cost 

($/yr)

Total HAP 

Emissions 

(Tons/yr)

HAP 

Emission 

Reductions 

from 

Baseline 

(Tons/yr)

Incremental 

HAP

Reduction 

(Tons/yr)

HAP Cost 

Effectiveness 

from 

Baseline 

($/Ton)

Incremental 

HAP Cost 

Effectiveness 

($/Ton)

LDAR Program

Baseline $1 ----- $44 ----- 0.492 ----- ----- ----- -----

Base LDAR $32,237 $32,236 $28,157 $28,113 0.169 0.323 0.3234 $86,933 $86,933

Option 1 $32,416 $179 $28,163 $6 0.116 0.376 0.0531 $74,691 $106

Option 2 $32,482 $66 $28,176 $13 0.108 0.384 0.0079 $73,182 $1,659

Pumps

Baseline $1 ----- $40 ----- 0.0950 ----- ----- ----- -----

Base LDAR $29,727 $29,726 $27,484 $27,444 0.0194 0.0756 0.0756 $362,885 $362,885

Option 1 $29,875 $148 $27,514 $30 0.0054 0.0896 0.0140 $306,464 $2,134

Option 2 $29,942 $66 $27,538 $24 0.0041 0.0909 0.0013 $302,458 $18,986

Valves

Baseline $0 ----- $3 ----- 0.1449 ----- ----- ----- -----

Base LDAR $30,440 $30,440 $27,727 $27,723 0.0964 0.0485 0.0485 $572,190 $572,190

Option 1 $30,470 $30 $27,731 $4 0.0574 0.0875 0.0391 $316,855 $110

Option 2 $30,624 $154 $27,780 $49 0.0507 0.0942 0.0067 $294,923 $7,369

Connectors

Baseline $0 ----- $1 ----- 0.0949 ----- ----- ----- -----

Base LDAR $29,720 $29,720 $27,466 $27,465 0.0501 0.0448 0.0448 $612,990 $612,990

Open-Ended Lines

Baseline $0 ----- $0 ----- 0.1576 ----- ----- ----- -----

Base LDAR $31,361 $31,361 $27,786 $27,786 0.0031 0.1545 0.1545 $179,837 $179,837

1 Equipment leak HAP emission factors and cost estimation methodology from Memorandum from Cindy Hancy, RTI to Jodi Howard, EPA, Analysis of 

Emission Reduction Techniques for Equipment Leaks, December 21, 2011. [EPA-HQ-OAR-2002-0037-0180]
14

4.3.2 “Low-Leak” Packing for Valves in Diisocyanate Service

As noted in Section 3.3, the EPA considered the results of the technology reviews for the (P&R 

IV, PAI, and Polyether PEPO source categories that were recently conducted for a 2012 

proposed RTR action for these source categories. One of the comments the EPA received on this 

proposed RTR action was that the EPA should also consider several additional improvements in 

LDAR programs that the EPA did not identify in this technology review. Therefore, as part of 

the technology review for the FPUF production source category, we also considered the 

comments received on the proposed RTR for the P&R IV, PAI and PEPO source categories for 

application to the FPUF production MACT standard. One potentially applicable suggestion was 

that “low-leak” technologies could be used for certain components. Therefore, we also evaluated 

low-leak valves in diisocyanate service in this analysis.

“Low-leak” packing for valves that significantly reduce emissions are in place in some facilities 

outside the FPUF Production source category, particularly oil refineries. Facilities and packing 

manufacturers have created emission testing protocols for low-leak packing in order to study and 

test their effectiveness.9 As described above, the use of low-leak technology was identified as a 

practice, process, or control technology that would be considered to be a development since the 

FPUF Production MACT standards were developed.

We analyzed the costs associated requiring low-leak valve technology for the FPUF Production

source category using costs for low-leak valves, which were previously estimated for the 

synthetic organic chemical manufacturing industry (SOCMI).

10,11 According to the SOCMI 

calculations, the nationwide total capital investment for low-leak valves was estimated to be $5.7 

billion. The nationwide annual cost for the SOCMI was $780 million/yr with a HAP emission 

reduction of 3,200 tpy.12

According to the background information for these costs, total capital investment and total 

annualized costs are proportional to the number of valves and therefore, proportional to the 

emissions from the valves. Thus, assuming that emissions from valves are constant and that the 

cost per valve is constant, we calculated a dollar per ton total capital investment factor for these 

low-leak valves of $3.9 million/ton HAP emissions and a total annualized cost factor of 

$542,000/yr/ton HAP (escalated from 2005 to 2011 dollars).13 ,14

Using these factors, nationwide annual costs for the FPUF Production source category were 

estimated to be $310,000/yr, with total capital investments of $2,260,000. Emission reductions 

 9 See Reference 5.

10 National Emission Standards for Hazardous Air Pollutants for Organic Hazardous Air Pollutants from the 

Synthetic Organic Chemical Manufacturing Industry: Proposed Rule. 71 FR 34422, June 14, 2006 11 Memorandum from Oommen, R., ERG, Morrisville, NC, to McDonald, R., U.S. Environmental Protection 

Agency, OAQPS. Cost and Emission Reduction of Leakless Valves for HON facilities. June 1, 2006. Docket No. 

EPA-HQ-OAR-2005-0475-0105. 12 Assuming VOC as a surrogate for HAP, because all HAP present (i.e., TDI) are VOC. See Reference 10. 13 Chemical Engineering Magazine. Economic Indicators. Chemical Engineering Plant Cost Index. CE Index for 

2005 is 468.2.

14 No cost basis for these values was presented in the background information. Therefore, it was assumed that these 

costs were presented in 2005 dollars.
15

were assumed to be 100 percent of the nationwide baseline emissions and were estimated to be 1 

tpy, with an estimated cost effectiveness of $305,000/ton HAP reduction. This analysis is 

presented in Table 6.

Table 6. Flexible Polyurethane Foam Equipment Cost and Cost Effectiveness Calculations 

for “Low-Leak” Packing

Source 

Category

Nationwide 

HAP 

Emissions 

from Valves 

(tpy)1

Nationwide 

Annual 

Cost2

# 

Facilities3

Annual 

Cost/ 

Facility

Nationwide 

Capital 

Cost2

Capital 

Cost/ 

Facility

Cost 

Effectiveness 

($/Ton 

reduced)4

FPUF

Production 1.01 $309,197 7 $44,171 $2,259,514 $322,788 $304,922

1 Represents baseline emissions, value based on calculation of potential VOC emissions per valve. Actual VOC 

and HAP emissions are for the FPUF source category are likely even lower than this assumption, considering 

the reported emissions in the EPA’s National Emissions Inventory for the facilities in this source category. 2 Based on total capital cost of $5.7 billion, total annual cost of $780 million, and HAP emission reduction of 

3,200, reported in the National Emission Standards for Hazardous Air Pollutants for Organic Hazardous Air 

Pollutants From the Synthetic Organic Chemical Manufacturing Industry: Proposed Rule. 71 FR 34422, June 14, 

2006. Also considers a 2005 CE Index of 468.2 and a 2011 CE index of 585.7. 3 Number of facilities represents slabstock facilities only. 4 Emission reductions assumed to be 100 percent of baseline emissions.

4.3.3 Repair Schedule for Diisocyanate Equipment Leaks

As noted in Section 3.3 and further above in section 4.4.2, the EPA considered the results of the 

technology reviews for the P&R IV, PAI, and PEPO source categories and the public comments 

received on the proposed RTR action for those source categories. One of the comments the EPA 

received on this proposed RTR action was that the EPA should also consider several additional 

improvements in LDAR programs that the EPA did not identify in this technology review. As 

part of the technology review for the FPUF Production source category, these suggestions were 

also considered for application to the FPUF Production MACT standard. One potentially 

applicable suggestion was that an LDAR program including tighter leak repair timelines be 

implemented, which some rules implemented by the California Bay Area Air Quality 

Management District (BAAQMD) and the California South Coast Air Quality Management 

District (SCAQMD) require. The FPUF Production MACT includes provisions regulating delay 

of repair for equipment leaks, but contains no limitation on the number of components awaiting 

repair. 

The BAAQMD Regulation 8, Rule 18 limits the number of equipment components awaiting 

repairs to 0.3 percent for valves, 0.025 percent for valves with major leaks (i.e., leaks greater 

than 10,000 ppm, including methane) and 1.0 percent for pumps and compressors. The 

BAAQMD also requires mass emission testing for non-repairable components with high leak 

rates and places an emission limit of 15 lbs/day on non-repairable components. The SCAQMD 

Rule 1173 limits the number of component awaiting repairs to 0.5 percent for valves and 1.0 

percent for pumps.
16

Background data for proposed amendments to BAAQMD Regulation 8 Rule 18 provides 

incremental costs associated with its amendment that lowers the number of components awaiting 

repairs from 0.5 percent to 0.3 percent for valves (no change was implemented for pumps, 

compressors, and pressure relief devices).15 The BAAQMD analysis was conducted for 233,000 

valves at five refineries (average of 46,600 valves per facility) located in the Bay Area District. 

Lowering the allowable percent of valves awaiting repairs from 0.5 to 0.3 percent was predicted 

to reduce emissions by 74 tpy (or by 57.1 percent). According to their analysis, BAAQMD 

estimated that an incremental total annualized cost associated with their amendment ranged from 

$34,200 to $173,000/yr per facility.16 These costs include the annual costs related to conducting 

mass emission rate determinations and cost to capture and control valves with excessive leaks. 

The BAAQMD estimated that mass emission rate determinations would apply to 60 valves per 

facility (or about 0.13 percent of the average number of valves at a facility). The BAAQMD 

estimated that the annualized cost of conducting the mass emission rate determinations would be 

range from $19,700 to $115,000/yr, 17 and the midpoint of the range is $67,100/yr or 

$1,120/yr/valve. Of these 60 valves, the BAAQMD assumed that about 2.5 percent would 

require control, or 2 valves per facility. The BAAQMD estimated that the annual cost of 

controlling these valves would range from $14,600 to $58,300/yr per facility,18 with a midpoint 

of $36,400 per year or $18,200/yr/valve. 

The BAAQMD approach was applied to a model plant for the FPUF Production source 

category.19 The results of this analysis are presented in Table 7. As shown in Table 7, the 

annualized cost associated with mass emission rate determinations for the FPUF Production

source category was estimated to be $1,120/yr and the annualized cost associated with control of 

valves with excessive leaks for the FPUF production model plant was estimated to be 

$18,200/yr. The cost effectiveness for the FPUF production model plant was estimated to be 

$234,000 per ton of HAP.

 15 Douglas, Victor, Compliance and Enforcement Division, BAAQMD. Draft Staff Report: Proposed Amendments 

Regulation 8 Rule 18: Equipment Leaks Control Measure SS-16. December 2003. See Attachment 4. 16 BAAQMD Costs were assumed to be in 2003 dollars. Costs escalated to 2011 dollars. CE Index for 2003 is 402 

and for 2011 is 585.7. See Reference 132. 17 See Reference 12. 18 See Reference 15. 19 Based on Model Plant 3 as identified in the 6/17/1996 memorandum: “Estimated Regulatory Alternative Impacts 

for Flexible Polyurethane Foam Production".
Table 7. Flexible Polyurethane Foam Production Equipment Cost & Cost Effectiveness Calculations for BAAQMD Repair Schedule

Number of 

Valves1,2

Uncontrolled 

Emissions 

(tpy)

Controlled 

Emissions 

(tpy)

Emissions 

Reductions 

(tpy)

Emission 

Reduction 

(%)

Emission 

Reduction per 

Valve 

(Ton/valve/yr)

Number of 

Valves 

Requiring 

Mass 

Measurements2

Percent of 

Valves 

Requiring 

Mass 

Measurement 

(%)

BAAQMD 46,600 26 11 14.7 57.1% 0.000316 60 0.129

FPUF 

Production

(slabstock 

diisocyanates)

32 0.145 .0622 0.08 57.1% 0.002584 1 3.125

Annual Cost 

of Mass 

Measurement 

($/yr)3,4

Annual Cost 

of Mass 

Measurement 

per Valve 

($/yr/valve)

Number of 

Valves 

with 

Excessive 

Leaking

Percent of 

Valves with 

Excessive 

Leaking 

(%)

Annual Cost 

of Excessive 

Leak 

Control 

($/yr)5

Annual Cost 

of Excessive 

Leak Control 

per Valve 

($/yr/valve)

Cost 

Effectiveness 

($/Ton)

BAAQMD $67,093 $1,118 2 3.33 $36,424 $18,212 $7,037

FPUF 

Production

(slabstock 

diisocyanates)

$1,118 -- 1 100.00 $18,212 -- $233,770

1 Number of components based on Model Plant 3 as identified in the 6/17/1996 memorandum: "Flexible Polyurethane Foam Model Plants.", available as part of “Hazardous Air 

Pollutant Emissions From The Production Of Flexible Polyurethane Foam: Supplementary Information Document For Proposed Standards” Emission Standards Division, U.S. 

EPA, September 1996. 2 Rounded up to the nearest whole number of valves. 3 Costs presented in Douglas, Victor, Compliance and Enforcement Division, BAAQMD. Draft Staff Report: Proposed Amendments Regulation 8 Rule 18: Equipment Leaks 

Control Measure SS-16. December 2003 were escalated to 2011 dollars. 2003 CE Index: 402, 2011 CE Index 585.7. See Attachment 4. 4 Calculated by dividing the annualized cost of mass emission determination from the BAAQMD cost estimate ($67,100/yr) by the number of valves in the BAAQMD estimate 

(60 valves), resulting in an average annualized cost per valve of $1,120/yr. This value was then applied to the FPUF production model plant. 5 Calculated by dividing the annualized cost of control of valves with excessive leaks ($36,400/yr) by the number of valves (60 valves) from the BAAQMD estimate, resulting in 

an average annualized cost per valve of $18,200/yr. This number was then multiplied by the number of valves in the model plant.