# Leak Detection and Repair A Best Practices GuideUnited States Environmental Protection Agency Offi ce of Compliance Offi ce of Enforcement and Compliance Assurance 1200 Pennsylvania A venue, NW (mail code) Washington, DC 20460Disclaimer The U.S. Environmental Protection Agency (EP A) has reviewed this document and approves it for publication. This document does not constitute rulemaking by the EP A and may not be relied on to create a substantive or procedural right or benefi t enforceable at law or in equity, by any person. The EP A may take actions at variance with this document and its internal procedures.

## Contents
1.0 Purpose
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 2.0 Why Regulate Equipment Leaks?
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 3.0 Sources, Causes And Control Of Equipment Leaks
. . . . . . . . . . . . . . . . . . . . . 3 3.1 How are emissions from equipment leaks reduced?
. . . . . . . . . . . . . . . 3 3.2 What regulations incorporate LDAR programs?
. . . . . . . . . . . . . . . . . . . 6 4.0 What Are the Benefi ts of an LDAR Program?
. . . . . . . . . . . . . . . . . . . . . . . . . . 7 4.1 Reducing Product Losses
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 4.2 Increasing Safety for Facility W orkers and Operators
. . . . . . . . . . . . . . . 8 4.3 Decreasing Exposure for the Surrounding Community
. . . . . . . . . . . . . . 8 4.4 Potentially Reducing Emission Fees
. . . . . . . . . . . . . . . . . . . . . . . . . . 8 4.5 Avoiding Enforcement Actions
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 5.0 Elements of an LDAR Program
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 6.0 What Compliance Problems Have Been Found W ith Current LDAR Programs?
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 7.0 Model LDAR Program
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 7.1 W ritten LDAR Program
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 7.2 Training
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 7.3 LDAR Audits
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 7.4 Contractor Accountability
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 7.5 Internal Leak Defi nition for Valves and Pumps
. . . . . . . . . . . . . . . . . . 22 7.6 More Frequent Monitoring
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 7.7 Repairing Leaking Components
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 7.8 Delay of Repair Compliance Assurance
. . . . . . . . . . . . . . . . . . . . . . . 24 7.9 Electronic Monitoring and Storage of LDAR Data
. . . . . . . . . . . . . . . . 24 7.10 QA/QC of LDAR Data
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 7.11 Calibration/Calibration Drift Assessment
. . . . . . . . . . . . . . . . . . . . . . 25 7.12 Records Maintenance
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 8.0 Sources of Additional Information
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

## T ables

T

able 3.1 Sources of equipment leaks
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 T

able 3.2 Equipment component counts at a typical refi nery or chemical plant
. . . . 5 T

able 3.3 Uncontrolled VOC emissions at a typical facility
. . . . . . . . . . . . . . . . . . 5 T

able 4.1 Control effectiveness for an LDAR program at a chemical process unit and a refi nery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7Leak Detection and Repair Compliance Assistance Guidance—A Best Practices Guide 

## Appendices
Appendix A Federal Regulations That Require a Formal LDAR Program W ith Method 21
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 Appendix B Federal Regulations That Require the Use of Method 21 But Do Not Require a Formal LDAR Program
. . . . . . . . . . . . . . . . . . . 30 Appendix C Method 21 General Procedure
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Appendix D Method 21—Determination of Volatile Organic Compound Leaks
. . . . . 32 Appendix E Summary of NEIC Comparative Monitoring Results of Leaking Valves at 17 Refi neries
. . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 Appendix F Enforcement Alert
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40Leak Detection and Repair—A Best Practices Guide 

## 1.0 Purpose

I ngen e r al , EP A has found s ignifi cant wi d e s p r e ad nonc ompli a nc e wi th L e ak D e t e ction and Re p air (LD AR) r e gul ations and mor e s p e c ifi call y

, noncompl i a nce wi th M e thod 21 r e quir em ents. I n1999, EP A es timat e d that, as a r e s ul to f thi s nonc ompl i a nce, an ad ditional 40,000 tons o f VO C s ar e emitt e d annual l y

fr om valves at p e tr ol eum r e fi n e ri es alon e. Th i s do cum e nt i s int e nd ed for use b y r e gul at e d entiti e s as we l las c o mpli anc e ins p e ctors to i d e ntify so me o f t h e p r ob le ms ide n t ifi ed wi th LDAR pr ogr ams fo cus i n g in on M e tho d21 r e quir em ents and d e scri b e th e pr actice s that can b e used to incr ease th e eff ectiven e s s o f an LDAR pr ogr a m . Sp ecifi cal l y

, thi s do cum e nt e x pl ains:

•Th e imp o r t ance o f r e gul atin g equipm ent le ak s ;
•Th e major el em ents o f an LDAR pr ogr a m ;
• T y

p i cal mi s t akes mad e wh en moni toring to de tec tle ak s ;
• P r obl e ms that o c cur fr om impr op er manag e m e nt o f an LDAR pr ogr a m ; and
• A set o f b e s tpr actices that can b e used to impl em ent eff ective an LDAR pr ogr a m . S o m e o f th e el em ents o f a mod e l LDAR pr ogr a m , as d e scri b ed in Se ction 7.0, ar e r e quir ed b y curr ent F e d e r al r e gul ations. O t h e r mo d e l LD AR progr a m el em ents h e lp ens u r e c o ntinuous c o mpli ance although th ey ma y not b e mand at ed fr om a r e gul ator y

s t andp oint. Fu r t h e rmor e, Stat e or lo cal r e quir em e nts ma y b e mor e s t ring ent than s o m e el em ents o f

th e mod e l LDAR pr ogr a m , s u ch as wi th l e ak de fi nitions. P r ior to d e ve lopin g a wr it t e n LD AR progr a m pl an , al l applicabl e r e gul ations shoul db e r e vi e wed to d e t e rmin e and ens u r e c o mpli ance wi th th e mo s ts t rin g ent r e quir em ents.

1According to EP A s 2002 National Emissions Inventory (NEI) database, 125,000 tons per year (tpy) of VOC are emitted from petroleum refi ner ies. It is estimated that over 49,000 tpy of VOC from refi neries are equipment leak emissions. Of the 165,000 tpy of VOC emissions from chemical manufacturing facilities, 21,000 tpy is attributable to equipment leaks. Leak Detection and Repair—A Best Practices Guide 

## 2.0 Why Regulate Equipment Leaks?

EP A has d e t e rmin ed that l e aking equipm ent, s u ch as val ve s, pumps, and c o nn e ctors, ar e th e l arg e s t s our ce o f emi s s ions o f v o l ati l e org a nic c o mp ound s ( VO C s ) and v o l ati l e hazar d ous air p o l l utants ( V HAP s ) fr om p e tr ol eum r e fi n e ri es and ch emical manufacturing faci l i t i e s. Th e Ag ency has es timat e d that ap pr o ximat el y 70,367 tons p e r year o f VO C s and 9,357 tons p e r year o f HAP s ha ve b e en emi t t e d from equipm ent l e ak s. Emi s s ions from equipm ent l e ak s exceed emi s s ions fr om s tor ag e ves sel s, was t e wat e r , tr ans f er op er ations, or pro c e s s ve nts. VO C s c o ntri but e to th e formation o f ground-l e vel o zon e. Ozon e i s a major c o mp on ent o f s m og, and causes or aggr a vat e s r e s p ir ator y d i sease, par t icul arl y in chi l d r e n , as thmatics, and h e al thy adul ts wh o par t icipat e in mod e r at e exer ci se. M a n y ar eas o f th e Un it ed St at e s, par t icul arl y

tho s e ar eas wh er e r e fi n e ri es and ch emical faci l i t i e s ar e lo cat e d , do not m e et th e N ational Ambi ent A i r Qu alit y Stand ar d(N A

A Q S) for o zon e. Ozon e can b e tr ansp o r t ed in th e atmo s p h e r e and c o ntri but e to nonatt ainm ent in downwi nd ar eas. S o m e s p eci e s o f VO C s ar e al s o cl as s i fi ed as VHAP s. S o m e kn own or s u s p ect e d eff ects o f exp o s ur e to VHAP s includ e cancer , r e pro ductive eff ects, and b i r t h d e f e cts. Th e high e s t c o nc entr ations o f VHAP s t e nd to b e clo s es t to th e emi s s ion s our ce, wh er e th e high es t publ ic exp o s ur e l e vel s ar e al s o o f t e n d e t e ct ed
. S o m e c o mmon VHAP s emi tt e d fr om r e fi n e ri es and ch emical pl ants includ e acetal d e hyd e, b e nzen e, formal d e h yd e, m e th yl en e chlori d e, naphthal en e, tolu en e, and x yl e n e .

’

-

2Leak Detection and Repair—A Best Practices Guide 

## 3.0 Sources, Causes And Control Of Equipment Leaks

A t y

p i cal r e fi n e r y or ch emical pl ant can emi t600­ 700 tons p e r year o f VO C s fr om l e aking equipm ent, s u ch as val ve s, c o nn e ctors, pumps, samplin g c o nn e ctions, c o mpr e s s ors, pr e s s u r e-r eli e f d e vi c e s, and op en-end ed l i n e s. T

abl e 3.1 show s th e primar y s our ces o f emi s s ions fr om c o mp on ents s ubject to equipm ent l e ak r e gul ations. I na t y

pical faci lit y

, mo s to f th e emi s s ions ar e from valve s and c o nn e ctors b e cause th e s e ar e th e mo s tpr e val ent c o mp on ents and can numb er in th e thousand s (T abl e 3.2). Th e major cause o f emi s s ions from valve s and c o nn e ctors i s seal or gasket fai lur e du e to normal wear or improp er maint e nance. P r e vious EP A s tudi e s ha ve es timat e d that val ves and c o nn e ctors ac c ount for mor e than 90% o f emi s s ions fr om l e aking equipm ent wi th valves b e ing th e mos ts ign ifi cant s our ce (T abl e 3.3). N e wer information s u gg e s ts that op en-end ed lin e s and samplin g c o nn e ctions ma y ac c ount for as much as 5-10% o f total VO C emi s s ions fr om equipm ent l e ak s. 3.1 How are emissions from equipment leaks reduced? F a ci l i t i e s can c o ntr o l emi s s ions fr om equipm ent l e ak s b y impl em entin g a l e ak d e t e ction and r e p air (LDAR) pr ogr a m or b y modi fying/r e p l a cing l e ak

ing equipm ent wi th “ l eak l es s ” c o mp on ents. M o s t equipm ent l e ak r e gul ations al low a c o mbination o f b o th c o ntr o l m e thod s.

• L e ak s fr om op en-end ed l i n e s, c o mpr e s s ors, and samplin g c o nn e ctions ar e us ual l y fi xe d b y modi fying th e equipm ent or c o mp on ent. Emi s s ions fr om pumps and val ves can al s o b e r e duced thr o ugh th e use o f “ l eak l es s ” valves and “ seal l es s ” pumps. Common l e ak l e s s val ves includ e b e l l ow s val ves and di aphr agm val ves, and c o mmon seal l es s pumps ar e di aphr a gm pumps, cann ed motor pumps, and magn etic drive pumps. L e ak s fr om pumps can al s o b e r e duced b y us ing dual seal s wi th or wi thout barri e r fl ui d
.

• L e ak l e s s valves and seal l es s pumps ar e effe ctive at minimi zin g or eliminatin g l e ak s, but th eir use ma y b e l i mi t e d b y mat e ri al s o f

c o ns tr uction c o ns i d e r ations and pro c e s s op er atin g c o nditions. I n s t al lin g l e ak l e s s and seal l es s equipm ent c o mp on ents ma y b e a wi se choice for r e pl acing ind ivi dual , chr o nic l e akin g c o mp on ents.
LDARis a work practice designed to identify leaking equipment so that emissions can be reduced through repairs. A component that is subject to LDAR requirements must be monitored at specifi ed, regular intervals to determine whether or not it is leaking. Any leaking component must then be repaired or replaced within a specifi ed time frame.

3Leak Detection and Repair—A Best Practices Guide

T

able 3.1 – Sources of equipment leaks.
Pumps are used to move fl uids from one point to another . Two types of pumps extensively used in petroleum refi neries and chemical plants are centrifugal pumps and positive displacement, or reciprocating pumps. Valves are used to either restrict or allow the movement of fl uids. Valves come in numerous varieties andwith the exception of connectors, are the most common piece of process equipment in industry

. Connectors are components such as fl anges and fi ttings used to join piping and process equipment together . Gaskets and blinds are usually installed between fl anges. Sampling connections are utilized to obtain samples from within a process.
Compressors are designed to increase the pressure of a fl uid and provide motive force. They can have rotary or reciprocating designs. Pressure relief devices are safety devices designed to protect equipment from exceeding the maximum allowable working pressure. Pressure relief valves and rupture disks are examples of pressure relief devices.
Open-ended lines are pipes or hoses open to the atmosphere or surrounding environment. Leaks from pumps typically occur at the seal.

Leaks from valves usually occur at the stem or gland area of the valve body and are commonly caused by a failure of the valve packing or O-ring.

Leaks from connectors are commonly caused from gasket failure and improperly torqued bolts on fl anges. Leaks from sampling connections usually occur at the outlet of the sampling valve when the sampling line is purged to obtain the sample. Leaks from compressors most often occur from the seals.
Leaks from pressure relief valves can occur if the valve is not seated properly, operating too close to the set point, or if the seal is worn or damaged. Leaks from rupture disks can occur around the disk gasket if not properly installed. Leaks from open-ended lines occur at the point of theline open to the atmosphere and are usually controlled by using caps, plugs, and fl anges. Leaks can also be caused by the incorrect implementation of the block and bleed procedure.

4Leak Detection and Repair—A Best Practices Guide

T

able 3.2 – Equipment component counts at a typical refi nery or chemical plant.
Component Range Average

Pumps 10 – 360 100 Valves 150 – 46,000 7,400 Connectors 600 – 60,000 12,000 Open-ended lines 1 – 1,600 560 Sampling connections 20 – 200 80 Pressure relief valves 5 – 360 90 Source: “Cost and Emission Reductions for Meeting Percent Leaker Requirements for HON Sources.” Memorandum to Hazardous Organic NESHAP Residual Risk and Review of T echnology Standard Rulemaking docket. Docket ID EP A-HQ-OAR-2005-0475-0105.

T

able 3.3 – Uncontrolled VOC emissions at a typical facility .
Component Average Uncontrolled VOC Emissions (ton/yr) Percent of Total Emissions Pumps 19 3 Valves 408 62 Connectors 201 31 Open-ended lines 9 1 Sampling connections 11 2 Pressure relief valves 5 1 T

otal 653Source: Emission factors are from Protocol for Equipment Leak Emission Estimates, EP A-453/R-95-017, Nov 1995, and equipment counts in T able 3.2. More recent dataindicates that openended lines and sampling connectionseach account for approximately 5-10% of total VOC emissions.

5For a comprehensive discussion of equipment leak regulation applicability determinations, see Inspection Manual: Federal Equipment Leak Regulations for the Chemical Manufacturing Industry, V ol. 1: Inspection Manual, EP A/305/B98/011 (Dec 1998), Chapter 2. Leak Detection and Repair—A Best Practices Guide

3.2 What regulations incorporate LDAR programs? LDAR pr ogr a ms ar e r e quir ed b y man y

N e w S our ce P e r f ormance St and ar d s (N SP S), N ational Emi s s ion Stand ar d s for H a zar d ous A i r P o l l utants (NE S HAP ), St at e I mpl em ent ation P l a ns ( S IP s ), th e Re s ourc e C o nser vation and Re c o ve r y A c t (RC R A), and oth e r s t at e or lo cal r e quir em ents. Th er e ar e 25 f e d e r al s t and ar d s that r e quir e faci l i t i e s to impl em ent LDAR pr ogr a ms. A p p e ndix A show s th e 25 f e d e r al s t and ar d s that r e quir e th e impl em ent ation o f a for

mal LDAR pr ogr a m us ing M e thod 21. A p p e ndix B li s t s 28 oth e r fed e r al r e gul ations that r e quir e s o m e M e thod 21 moni toring, but do not r e quir e LDAR pr ogr a ms to b e in pl ace.

• N S P S (40 C F R P ar t60) equipm ent l e ak s t and ar d s ar e r e l at e d to fugi tive emi s s ions o f VO C s and appl y to s t ationar y s ourc e s that c o mm enc e c o ns tr uction , mo difi cation , or r e c o ns tr uction aft e r th e d at e that an N S P S i s pr op o sed in th e F e d e r al Regi s t er. • NE SHAP (40 C F R P ar t s 61, 63, and 65) equipm e nt l e ak s t and ar d s ap pl y to b o th n e w and e xi s tin g s t ationar y s ourc e s o f fu gitive VHAP s.
• RC RA (40 C F R P ar t s 264 and 265) equipm ent l e ak s t and ar d s ap pl y to hazar d ous was t e tr eatm ent, s tor ag e, and d i s p o s al faci l i t i e s.
• M a n y

s t at e and lo cal air ag enci es inc o rp or at e f e d e r al LDAR r e quir em ents b y r e f e r e nce, but s o m e ha ve es tabl i s h e d mor e s t ring ent LDAR r e quir em ents to m e et lo cal air qual i t y n e ed s. A faci l i t y ma y ha ve equipm ent that i s s ubject to multipl e N S P S and NE SHAP equipm ent l e ak s s t and ar d s. F o r exampl e, a numb er o f manufacturing pr o c es ses l i s t ed in th e H a zar d ous O rg a nic NE SHAP (HO N) equipm ent l e ak s t and ar d(40 C F R 63, Sub p ar t H) ma y uti l i z e equipm ent for wh ich oth e r NE SHAP or N S P S equipm ent l e ak s t and ar d s c o ul d ap pl y ( s uch as 40 C F R 60, Sub p ar t V V ). I nad di

tion , on e pro c e s s lin e ma y b e s ubje ct to on e r ul e and anoth e r pr o c es s l i n e s ubject to anoth e r r ul e. F a ci l i t i e s mus tens u r e that th ey ar e c o mpl ying wi th th e prop er equipm ent l e ak r e gul ations if multipl e r e gul ations appl y

.

6Leak Detection and Repair—A Best Practices Guide 

## 4.0 What Are the Benefi ts of an LDAR Program?

Wh en th e LD AR r e quir em ents we r e d e ve lop e d , EP A es timat e d that p e tr ol eum r e fi n e ri es c o ul d r e duce emi s s ions fr om equipm ent l e ak s b y 63% b y impl em e ntin g a faci lit y LD AR progr a m . Ad ditional l y

, EP A es timat e d that ch emical faci l i t i e s c o ul d r e duce VO C emi s s ions b y 56% b y impl em enting s u ch a progr a m . T

abl e 4.1 pr esents th e c o ntr o l eff e ctive n e s s o f an LDAR pr ogr a m for di ff er ent monitorin g int e r val s a n dle ak de fi nitions at ch emical pro c e s s units and p e tr ol eum r e fi n e ri es. Emi s s ions r e ductions from impl em entin g an LD AR pr ogr a m p o t e nti al l y r e duce pr oduct lo s s es, incr ease safet y

for w o rkers and op er ators, d e cr ease exp o s ur e o f

th e s u rroundin g c o mmunit y

, r e duce emi s s ions fe e s, and h e lp faci liti e s a v oi d enforc em ent actions. Example – Emissions reductions at a typical SOCMI facility . Applying the equipment modifi cations and LDAR requirements of the HON to the sources of uncontrolled emissions in the typical facility presented in T ables 3.2 and 3.3 would reduce the emissions per facility by approximately 582 tons per year of emissions, an 89% reduction.
T

able 4.1 – Control effectiveness for an LDAR program at a chemical process unit and a refi nery .

Equipment T ype and Service Control Effectiveness (% Reduction) Monthly Monitoring

10,000 ppmv Leak Defi nition Quarterly Monitoring 10,000 ppmv Leak Defi nition 500 ppm Leak Defi nition a Chemical Process Unit Valves – Gas Service b 87 67 92 Valves – Light Liquid Service c 84 61 88 Pumps – Light Liquid Service c 69 45 75

Connectors – All Services 93 Refi

nery Valves – Gas Service b 88 70 96 Valves – Light Liquid Service c 76 61 95 Pumps – Light Liquid Service c 68 45 88

Connectors – All Services 81 Source: Protocol for Equipment Leak Emission Estimates, EP A-453/R-95-017, Nov 1995.

a Control effectiveness attributable to the HON-negotiated equipment leak regulation (40 CFR 63, Subpart H) is estimated bas ed on equipment-specifi c leak defi nitions and performance levels. However, pumps subject to the HON at existing process units have a 1,000 to 5,000 ppm leakdefi nition, depending on the type of process. b Gas (vapor) service means the material in contact with the equipment component is in a gaseous state at the process operatingconditions. c Light liquid service means the material in contact with the equipment component is in a liquid state in which the sum of the concentration of individual constituents with a vapor pressure above 0.3 kilopascals (kPa) at 20°C is greater than or equal to 20% by weight.

7Leak Detection and Repair—A Best Practices Guide

4.1 Reducing Product Losses I nth e p e tr o c h e mical indus t r y , sal e abl e pr oducts ar e lo s twh en e ver emi s s ions e scap e from pro c e s s equipm ent. L o s tpr oduct g e n e r al l y tr ansl at es into lo s tr e venu e. 4.2 Increasing Safety for Facility W orkers and Operators M a n y

o f th e c o mp ound s emi t t e d fr om r e fi n e ri es and ch emical faci l i t i e s ma y p o s e a hazar dto ex

p o sed w o rkers and op er ators. Reducing emi s s ions fr om l e aking equipm ent has th e di r e ct b e n e fi t o f r e ducin g o c cup ational e x p o s ur e to hazar d ous c o mp ound s . 4.3 Decreasing Exposure for the Surrounding Community I nad dition to w o rkers and op er ators at a faci lit

y

, th e p o pul ation o f a s u rroundin g c o mmunit y can b e aff ect e d b y se ver e, long-t erm exp o s ur e to to xic air p o l l utants as a r e s ul to f l e aking equipm e nt. A l though mo s to f th e c o mmuni t y exp o s ur e ma y b e e p i s odic, chr o nic h e al th eff e c ts can r e s ult fr om long-t erm exp o s ur e to emi s s ions fr om l e aking equipm ent that i s ei th er not i d e ntifi ed as l e aking or not r e pair ed
. 4.4 Potentially Reducing Emission Fees T

o fund p e rmi tting pr ogr a ms, s o m e s t at es and lo cal air p o l l ution di s t ricts charge annual fe e s that ar e based on total faci l i t y emi s s ions. A faci l i t y wi th an eff ective pr ogr a m for r e ducing l e aking equipm ent can p o t e nti al l y d e cr ease th e amount o f th e s e annu al fe e s . 4.5 A voiding Enforcement Actions I nsett in g C o mpli anc e and Enforc em ent N ational P r iori t i e s for A i r T o xics, EP A has i d e ntifi ed LD AR progr a ms as a national fo cus. Th er efor e, faci l i t i e s can exp e ct an incr eased numb er and fr equ e nc y o f c o mpli anc e ins p e ctions and a clo ser r e vi e w o f c o mpl i a nce r e p o r t s s ubmi tt e d to p e rmi tting authori t i e s in an eff or t b y th e Ag ency to as ses s LDAR pr ogr a ms and i d e ntify p o t e nti al LDAR pr obl e ms. A faci li t

y wi th an eff ective LDAR pr ogr a m d e cr eases th e chanc e s o f b e in g t arg et ed for enforc em ent actions and a v oi d s th e c o s t s and p e nal t i e s as s o ci at ed wi th r ul e vi o l ations.

Example – Cost of product lost. In previous rulemaking efforts, EP A has esti­ mated that the average value of product lost due to equipment leaks is $1,370 per ton. a Applying this cost factor results in a potential savings of $730,000 per year per facility

. a Source: Hazardous Air Pollutant Emissions From Process Units in the Synthetic Organic Chemical Manufacturing Industry-Background Information for Proposed Standards, V ol. 1C-Model Emission Sources. Emission Standards Division, US EP A, Offi ce of Air and Radiation, OAQPS, Research Triangle Park, NC. Nov 1992.

8Leak Detection and Repair—A Best Practices Guide 

## 5.0 Elements of an LDAR Program

Th e r e quir em ents amon g th e r e gul ations var y , F o r each el em ent, thi s se ction outlin e s th e t y

pical but al l LDAR pr ogr a ms c o ns i s t o f five bas i c el e- LD AR progr a m r e quir em ents, c o mmon c o mpli ance m e nts, wh ich ar e di scus sed in d e t ai lin Se ctions 5.1 pro b l e ms found throu gh fi el d ins p e ctions, and a thr o ugh 5.5. set o f b e s tpr actices used b y faci l i t i e s wi th eff e ctive LDAR p r ogr a ms.

Identifying Components

Leak Defi nition

Monitoring Components

Repairing Components

Recordkeeping

9Leak Detection and Repair—A Best Practices Guide

Current Requirements • Assign a unique identifi cation (ID) number to each regulated component. • Record each regulated component and its unique ID number in a log. • Physically locate each regulated component in the facility, verify itslocation on the piping and instrumentation diagrams (P&IDs) or process fl ow diagrams, and update the log if necessary

. Some states require a physical tag on each component subject to the LDAR requirements. Leak Defi nition • Identify each regulated component on a site plot plan or on a continuously updated equipment log. • Promptly note in the equipment log when new and replacement pieces of equipment are added and equipment is taken out of ser

vice. Monitoring Components Common Problems • Not properly identifying all regulated equipment components. • Not properly documenting exempt components (e.g., <300 hour exemption and <5 (or <10) weight % HAP). Repairing Components Best Practices • Physically tag each regulated equipment component with a unique ID number

. • Write the component ID number on piping and instrumentation diagrams. • Institute an electronic data management system for LDAR data and records, possibly including the use of bar coding equipment. • Periodically perform a fi eld audit to ensure lists and diagrams accurately represent equipment installed in the plant. Identifying Components

Recordkeeping

10Leak Detection and Repair—A Best Practices Guide

Current Requirements • Method 21 requires VOC emissions from regulated components to be measured in parts per million (ppm). A leak is detected whenever the measured concentration exceeds the threshold standard (i.e., leak defi nition ) for the applicable regulation.

– Leak defi nitions vary by regulation, component type, service (e.g., light liquid, heavy liquid, gas/vapor), and monitoring interval.

– Most NSPS have a leak defi nition of 10,000 ppm. Many NESHAP use a 500-ppm or 1,000-ppm leak defi nition. Leak Defi nition • Many equipment leak regulations also defi ne a leak based on visual inspections and observations (such as fl uids dripping, spraying, misting or clouding from or around components), sound (such as hissing), and smell. Note: The LDAR requirements specify weekly visual inspections of Monitoring Components pumps, agitators, and compressors for indications of liquids leaking from the seals. Identifying Components

Repairing Components Common Problems • Using the wrong leak defi nition for a particular component due to confusion at facilities where multiple LDAR regulations apply

. Best Practices • Utilize a leak defi nition lower than what the regulation requires. • Simplify the program by using the lowest leak defi nition when multiple leak defi nitions exist. Recordkeeping • Make the lowest leak defi nition conservative to provide a margin of safety when monitoring components. • Keep the lowest leak defi nition consistent among all similar component types. For example, all valves in a facility might have a leak defi nition of 500 ppm.

11Leak Detection and Repair—A Best Practices Guide

Identifying Components

Leak Defi nition

Monitoring Components

Repairing Components

Recordkeeping

The monitoring interval is the frequency atwhich individual component monitoring is conducted. For example, valves are generally required to be monitored once amonth using a leak detection instrument, but the monitoring inter

val may be extended (e.g. to once every quarter for each valve that has not leaked for two successive months for Part 60 Subpart VV , or on a process unit basis of once every quarter for process units that have less than a 2% leak rate for Part 63 Subpart H). Current Requirements • For many NSPS and NESHAP regulations with leak detection provisions, the primary method for monitoring to detect leaking components is EP A Reference Method 21 (40 CFR Part 60, Appendix A). • Method 21 is a procedure used to detect VOC leaks from process equipment using a portable detecting instrument. • Appendix C of this guide explains the general procedure and Appendix D presents the complete Method 21 requirements. • Monitoring intervals vary according to the applicable regulation, but are typically weekly, monthly, quarterly, and yearly

. For connectors, the monitoring interval can be every 2, 4, or 8 years. The monitoring interval depends on the component type and periodic leak rate for the component type. Common Problems • Not following Method 21 properly

. • Failing to monitor at the maximum leak location (once the highest reading is obtained by placing the probe on and around the interface, hold the probe at that location approximately two times the response rate of the instrument). • Not monitoring long enough to identify a leak. • Holding the detection probe too far away from the component interface. The reading must be taken at the interface. • Not monitoring all potential leak interfaces. • Using an incorrect or an expired calibration gas. • Not monitoring all regulated components. • Not completing monitoring if the fi rst monitoring attempt is unsuccessful due to equipment being temporarily out of service. Best Practices • Although not required by Method 21, use an automatic (electronic) data logger to save time, improve accuracy, and provide an audit record. • Audit the LDAR program to help ensure that the correct equipment is being monitored, Method 21 procedures are being followed properly, and the required records are being kept. • Monitor components more frequently than required by the regulations. • Perform QA/QC of LDAR data to ensure accuracy, completeness, and to check for inconsistencies. • Eliminate any obstructions (e.g., grease on the component interface) that would prevent monitoring at the interface. • If a rule allows the use of alternatives to Method 21 monitoring, Method 21 should still be used periodically to check the results of the alternative monitoring method.
12Leak Detection and Repair—A Best Practices Guide

Identifying Components

Leak Defi nition

Monitoring Components

Repairing Components

Recordkeeping Current Requirements • Repair leaking components as soon as practicable, but not later than a specifi ed number of calendar days (usually 5 days for a fi rst attempt at repair and 15 days for fi nal attempt at repair) after the leak is detected. • First attempts at repair include, but are not limited to, the following practices where practicable and appropriate: • Tightening bonnet bolts • Replacing bonnet bolts • Tightening packing gland nuts • Injecting lubricant into lubricated packing • If the repair of any component is technically infeasible without a process unit shutdown, the component may be placed on the Delay of Repairlist, the ID number is recorded, and an explanation of why the component cannot be repaired immediately is provided. An estimated date for repairing the component must be included in the facility records. Note: The “drill and tap” method for repairing leaking valves is gener

ally considered technically feasible without requiring a process unit shutdown and should be tried if the fi rst attempt at repair does not fi x the leaking valve. See section 6.7 for a discussion of “drill and tap”. • The component is considered to be repaired only after it has been monitored and shown not to be leaking above the applicable leak defi nition. Common Problems • Not repairing leaking equipment within the required amount of time specifi ed by the applicable regulation. • Improperly placing components on the Delay of Repair list. • Not having a justifi able reason for why it is technically infeasible to repair the component without a process unit shutdown. • Not exploring all available repair alternatives before exercising the Delay of Repair exemption (specifi cally as it pertains to valves and “drill and tap” repairs). Best Practices • Develop a plan and timetable for repairing components. • Make a fi rst attempt at repair as soon as possible after a leak is detected. • Monitor components daily and over several days to ensure a leak has been successfully repaired. • Replace problem components with “leakless” or other technologies.

13Leak Detection and Repair—A Best Practices Guide

Identifying Components

Leak Defi nit ion

Monitoring Components

Repairing Components

Recordkeeping Current Requirements For each regulated process: • Maintain a list of all ID numbers for all equipment subject to an equipment leak regulation. • For valves designated as “unsafe to monitor,” maintain a list of IDnumbers and an explanation/review of conditions for the designation. • Maintain detailed schematics, equipment design specifi cations (including dates and descriptions of any changes), and piping and instrumentation diagrams. • Maintain the results of performance testing and leak detection monitoring, including leak monitoring results per the leak frequency, monitoring leakless equipment, and non-periodic event monitoring. For leaking equipment: • Attach ID tags to the equipment. • Maintain records of the equipment ID number, the instrument and operator ID numbers, and the date the leak was detected. • Maintain a list of the dates of each repair attempt and an explanation of the attempted repair method. • Note the dates of successful repairs. • Include the results of monitoring tests to determine if the repair was successful. Common Problems • Not keeping detailed and accurate records required by the applicable regulation. • Not updating records to designate new components that are subject to LDAR due to revised regulations or process modifi cations. Best Practices • Perform internal and third-party audits of LDAR records on a regular basis to ensure compliance. • Electronically monitor and store LDAR data including regular QA/QC audits. • Perform regular records maintenance. • Continually search for and update regulatory requirements. • Properly record and report fi rst attempts at repair

. • Keep the proper records for components on Delay of Repair lists.

14Leak Detection and Repair—A Best Practices Guide 

## 6.0 What Compliance Problems Have Been Found W ith Current LDAR Programs? M a ny r e gul ator y ag enci es d e t e rmin e th e c o mpl i

ance s t atus o f LDAR pr ogr a ms based on a r e vi e w o f s ubmi tt e d pap e r w ork. S o m e c o nduct wal k -thr ough ins p e ctions to r e vi e w LD AR r e c o r d s maint ain ed on s i t e and p e r f orm a vi s u al ch eck o f moni toring pr actices. H o we ver , a r e c o r d s r e vi e w wi l lnot show if monitorin g pro c edur e s ar e b e in g fo l l owed
. Simil arl y

, th e t y

pical wal k throu gh ins p e ction wi l lnot li ke l y

d e t e ct improp er monitorin g pr actic e s s i nc e op er ators wi l lt e nd to ens u r e that th e y ar e fo l l owin g prop er pro c edur e s wh en th e y ar e b e in g watch e d
. EP A

’s N ational Enforc em ent I n ve s tigations C e nt er (NEIC ) c o nduct e d a numb er o f sampl i ng in ves tig a tions o f LD AR progr a ms at 17 p e tro l eum r e fi n e ri es. A

p p e ndix E s ummari z es th e c o mpar ative moni tor

ing r e s ul t s, and A p p e ndix F c o ntains a c o p y o f th e 1999 Enfor c em ent A l er t that expl ains th e moni tor

ing r e s ul t s. Th e in ve s tigations c o ns i s t e d o f r e c o r d s r e vi e w and c o mp ar ative l e ak m o nitorin g ( c omp ar in g th e l e ak r at e found b y NEIC to th e faci l i t y ’s hi s toric l e ak r at e ) at a s ubset o f th e faci l i t y ’s total c o mp on ents. Th e s e in ve s tigations ha ve shown a patt ern o f s ignifi cantl y high er equipm ent l e ak r at e s (5%) than wh at th e r e fi n e ri es r e p o r t ed (1.3%). Wh i l e th er e ha ve b e en impr ovem ents s i nce 1999, faci l i t y audi t s ar e s t i l lshowing s ignifi cantl y el e vated l e ak r at e s, es p e ci al l y

in th e ch emical manufactu ring indus t ri es. Th e di scr e p anc y in l e ak r at e s indicat e s that monitorin g s t aff ma y not b e c o mpl ying wi th M e thod 21 pr o c edur es. F ai l ur e to accur at e l y

d e t e ct l e ak s ma y b e du e to a l a ck o f int e rnal qual i t y c o ntr o l overs ight or manag e m e nt acc ountab i l i t y for th e LDAR pr ogr ams r e g ar d l e s s o f wh eth e r th e moni toring i s don e b y c o ntr a ctors or in-house p e rs onn e l
. Each l e ak that i s not d e t e ct ed and r e pair ed i s a lo s t op p o r tuni t y to r e duce emi s s ions. I nth e O ctob e r 1999 Enfor c em ent A l er t, EP A es timat e s that an additional 40,000 tons o f VO C s ar e emit t e d annual l y from p e tro l eum r e fi ne ries bec aus e le ak i ng val ves ar e not found and r e pair ed
. Se ve r al imp o r t ant factors c o ntri but e to fai lin g to i d e nti f y and r e p air l e akin g c o mp on ents: 1. No t i d entif yin g al l r e gul at ed c o mp on e nt s/unit s in in ventor y I f

a faci l i t y does not pr op erl y

i d e ntify al l o f i t s r e gul at e d c o mp on ents, s o m e l e ak s ma y go u n ide n t ifi ed
. Un i d e ntifi ed c o mp on ents ma y l e ak or ha ve exi s ting l e ak s that wi l lw o rsen over tim e if th e c o mp on ents ar e not pr op erl y ide n t ifi ed , moni tor ed and r e pair ed
. F a ci l i

ti es can fai l to i d e ntify r e gul at e d c o mp on ents wh en n e w pr o c es ses ar e c o ns tr uct e d , exi s ting pr o c es s ar e modi fi ed , or n e w or r e vi sed equipm ent l e ak r e gul ations ar e publi s h e d
. 2. No t m o nitorin g c o mp on ent s I ns o m e cases, th e numb er o f c o mp on ents r e p o r t ed to ha ve b e en monitor ed ma y indicat e pr obl e ms wi th moni toring pr o c edur es. Wh at faci lit y ins p e ctors ha ve found:

• A d ata logg er tim e s t amp showed val ves b e ing moni tor ed at th e r at e o f on e p e r sec o nd wi th t w o val ves o c cas ional l y

b e 15Leak Detection and Repair—A Best Practices Guide
ing moni tor ed wi thin th e sam e 1-sec ond p e riod
. • A ton e faci l i t y

, a p e rs on r e p o r t ed moni tor

ing 8,000 c o mp on ents in on e d a y ( a s s uming an 8-hour w o rk d a y

, that r e pr esents on e c o mp on ent e ver y 3.6 sec o nd s )
. • Re c o r d s e valuations showed wi d e l y

var ying c o mp on ent moni toring c ounts, s u gg e s t ing equipm ent might not alwa y s b e monitor ed wh en r e quir ed
. • Equipm ent was marked “ t e mp or ari l y out o f

ser vi c e” b e cause th e initi al ins p e ction at

t e mpt c o ul d not b e p e r f orm e d
. H o we ver

, th e equipm ent was in ser vi ce for mo s t o f

th e p e riod , and no s ubsequ e nt (o r prior) ins p e ction att e mpts we r e p e r f orm e d to m e et th e monitorin g r e quir em ent. H o we ver , e ven wh en r e c o r d s show a r e al i s tic numb er o f c o mp on ents ar e b e in g monitor ed , if th er e ar e no overs ight or acc ountab i l i t y ch eck s, th en th er e i s no guar ant e e that c o mp o n e nts ar e actu al l y

b e ing moni tor ed
.

A well-trained LDAR inspection team (two people) can monitor approximately 500-700 valves per day

. 3. I n s u ffi ci ent tim e to i d entif y

a l e ak I noth e r cases, faci l i t i e s ar e not fol l owing prop er monitorin g pro c edur e s, r e s ultin g in a lower numb er o f l e aking c o mp on ents b e ing r epo rte d
.

• I f a w o rker moves th e pr ob e ar ound th e c o mp on ent int e r f ace s o r a p i d l y that th e ins t r u m e nt does not ha ve tim e to pr op erl y r e s p ond , th en a c o mp on ent ma y n e ver b e ide n t ifi ed as l e akin g . • I f a w o rker fai l s to fi nd th e maximum l e ak lo cation for th e c o mp on ent and th en do e s not s p end t wice th e r e s p onse tim e at that lo cation , th en th e monitorin g ins t r u m e nt wi l lnot m e as ur e th e c o rr ect c o ncentr ation o f hydro carb o ns and th e l e ak ma y go und e t e ct ed
. O p tical l e ak ima gin g show s th e imp o r t anc e o f i d entif yin g th e ma ximum l e ak lo cation , a s h

ydro car b o n s ar e quickl y

di sp ersed and di lut ed by air curr ent s around th e c o mp on ent . 4. H o l din g th e prob e a wa y

from th e c o mp on e nt int e r f ac e Th e pr ob e mus tb e pl aced at th e pr op er int e r f ace o f th e c o mp on ent b e ing anal yzed
. P l a cing th e pr ob e e ven 1 centim et er fr om th e int e r f ace can r e s ult in a fal se r e adin g, indicating that th e c o mp on ent i s not l e aking, wh en in fact i ti s l e aking. El iminat e an y i s s u es (e.g., gr ease on th e c o mp on ent int e r f ace ) that pr event moni toring at th e int e r f ace (e.g., r e move exce s s gr ease from th e c o mp on ent b efor e moni toring or use a moni tor that w o n ’t b e impact ed b y th e gr ease and i s easy to cl ean .

16A California Bay Area Air Quality Management District rule effectiveness study showed that if an operator measured 1 centimeter (0.4 inches) from the component leak interface, the operator would fi nd only 79% of valves leaking between 100 ppm and 500 ppm and only 43% of the valves leaking above 500 ppm. Source: Draft Staff Report, Regulation 8, Rule 18, Equipment Leaks, Bay Area Air Quality Management District, Jul 1997. Leak Detection and Repair—A Best Practices Guide

F o r equipm ent wi th r o tating shafts ( p umps and c o mpr e s s ors ), M e thod 21 r e quir es th e pr ob e b e pl aced wi thin 1 centim et er o f th e

T

ypical TV A (T oxic Vapor Analyzer) response times are around 2 – 4 seconds.

shaft-seal int e r f ace. P l a cing th e pr ob e at th e s u r f ace o f th e r o tating shaft i s a saf e t

y

hazar d a n ds h o uldbe a v oide d
. 5. Fai l in g to prop erl y

m aint ain m o nitorin g in s tr u m e nt F a ctors that ma y pr e vent th e ins t r u m e nt fr om i d e ntifying l e ak s ar e:

• N o t us ing an ins t r u m e nt that m e ets th e sp e c i fi cations r e quir ed in M e tho d21, se ction 6.
• D i r t y ins t r u m e nt pr ob es;
• L e akag e fr om th e ins t r u m e nt pr ob es;
• N o t zer o ing ins t r u m e nt m e t e r ;
• In c o rre ct calibration gase s used; and
• N o t cali br atin g th e d e t e ction ins t r u m e nt on a d ai l y bas i s. 6. I mprop erl y

i d entif yin g c o mp on ent s a s “un safe ” or “ diffi c u lt ” to m o nitor C o mp on ents that ar e i d e nti fi ed as b e in g “unsaf e to moni tor” or “ diffi cult to monitor ” m u s tbe ide n t ifi ed as s u ch b e cause th er e i s a saf e t

y

c o ncern or an acces s i b i l i t y i s s u e that pr e vents th e c o mp on ent fr om b e ing s u cces sful l y moni tor ed
. A

l l unsaf e or di ffi cul t-to-moni tor c o mp on e nts mus tb e includ ed on a log wi th i d e ntifi cation numb ers and an e x pl anation o f why th e c o mp on ent i s “unsaf e to moni tor” or “ diffi cult to monitor
. ” M o nitorin g can b e d e ferr ed for al l s u ch c o mp on ents, but th e faci l i t y mus t maint ain a pl an that e x pl ains th e c o nditions und e r wh ich th e c o mp on ents b e c o m e saf e to monitor or no lon ger diffi cult to monitor
.

17Leak Detection and Repair—A Best Practices Guide

7. I mprop erl y

pl acin g c o mp on ent s/unit s on th e “ D el a y

o f Rep air ” l i s t G e n e r al l y

, pl acing a l e aking c o mp on ent on th e “ D el a y

o f Re pair” l i s ti s p e rmi s s i bl e onl y wh en th e c o mp on ent i s t e chnical l y inf e as i b l e to r e pair wi thout a pr o c es s uni tshutdown (e.g., for val ves th e own e r/op e r ator mus t d e mons tr at e that th e emi s s ions fr om imm edi at e r e pair wi l lb e gr eat e r than wai t ing for uni tshutdown ). Re pair m e thod s ma y exi s t, s u ch as “ d ri l land tap” for valves, that al low l e ak s to b e fi xe d wh i l e th e c o mp on ent i s s t i l lin ser vi ce. F ai l

ing to c o ns i d e r s u ch r e pair m e thod s b efor e exer ci s i ng th e “ D el a y

o f Re pair” l i s tma y c o ns t i tut e nonc ompl i a nce wi th r e pair r e quir em e nts (u s u al l y

15 d a y s und e r f e d e r al LDAR s t and ar d s ). Comp on ents pl aced on th e “ D el a y

o f Re pair” l i s tmus tb e acc o mpani e d b y th eir ID numb e rs and an e x pl anation o f why th e y ha ve b e en pl aced on th e l i s t. Th ese c o mp on ents cannot r e main on th e li s tind e fi ni t e l y

– th ey mus tb e r e pair ed b y th e end o f th e n e xt pr oces s uni tshutdown . Drill and T a p is a repair method wherea hole is drilled into the valve packing gland and tapped, so that a small valve and fi tting can be attached to the gland. A packing gun is connected to this fi tting and the small valve is opened allowing new packing material to be pumped into the packing gland. Many companies consider this a permanent repair technique, as newer, pumpable packingtypes are frequently superior to the older packing types they replace. Packing types can be changed and optimized for the specifi c application over time.

18Leak Detection and Repair—A Best Practices Guide 

## 7.0 Model LDAR Program

E x p e ri ence has shown that faci l i t i e s wi th an effective r e c o r do f pr e venting l e ak s int e gr at e an a war enes s o f t h e be ne fi ts o f l e ak d e t e ction and r e p air into th eir op er ating and maint e nance pr ogr a m . Th is se ction outlin e s s o m e o f th e major el em ents o f s u cces s ful LDAR pr ogr a ms. Th ese pr ogr a m el em ents we r e de ve l o pe d f r o m :

• Evaluation o f b e s tpr actic e s i d e ntifi ed at faci l i t i e s wi th s u cces s f ul LDAR pr ogr a ms, and
• An al y s i s o f th e r o ot causes o f nonc ompl i a nce at faci liti e s that we r e found to ha ve r e currin g vi o l ations o f LD AR r e gul ator y r e quir em ents. LDAR pr ogr a ms that inc o rp or at e mo s tor al l o f th e el em ents d e scri b ed in th e fo l l owin g se ctions ha ve achi e ved mor e c o ns i s t e nt r e s ul t s in th eir LDAR pr ogr a ms, l e ading to in cr eased c o mpli ance and lowe r emi s s ions.

Written LDAR Program (Section 7.1)

Training (Section 7.2)

QA/QC of LDAR Data (Section 7.10) Calibration/Calibration Drift Assessment

(Section 7.11) Electronic Monitoring

and Storage of Data (Section 7.9) First Attempt at Repair (Section 7.7)

More Frequent Monitoring (Section 7.6) LDAR Audits (Section 7.3) Contractor Accountability (Section 7.4)
Internal Leak Defi nitions (Section 7.5)

Records Maintenance (Section 7.12)Delay of Repair Compliance Assurance

(Section 7.8)

M odel L DAR P rogram

19Leak Detection and Repair—A Best Practices Guide

7.1 W ritten LDAR Program A wr i t t e n LDAR pr ogr a m s p ecifi e s th e r e gul ator y r e quir em ents and faci l i t y-s p e cifi c pro c edur e s for r e co r d ke ep i n g ce rt ifi cations, monitorin g, and r e p airs. A wr i tt e n pr ogr a m al s o d e l i n e at es th e r o l e s o f each p e rs on on th e LDAR t eam as wel las do cum e nts al l th e r e quir ed pr o c edur es to b e c o mpl e t e d and d ata to b e g ath er ed , thus es tabl i s hing acc ountab i l i t y

. Th e pl an shoul di d e ntify al l pr o c es s uni t s s ubject to fed e r al , s t at e, and lo cal LD AR r e gul ations and b e upd at e d as n e ces s ar y to ens u r e accur a cy and c o ntinuin g c o mpli an c e . Elements: • An overall, facility-wide leak rate goal that will be a target on a process-unit-by-process-unit basis; • A list of all equipment in light liquid and/or in gas/ vapor service that has the potential to leak VOCs and VHAPs, within process units that are owned and maintained by each facility; • Procedures for identifying leaking equipment within process units; • Procedures for repairing and keeping track of leak­ ing equipment; • A process for evaluating new and replacement equipment to promote the consideration of install­ ing equipment that will minimize leaks or eliminate chronic leakers; • A list of “LDAR Personnel” and a description of their roles and responsibilities, including the person or position for each facility that has the authority to implement improvements to the LDAR program; and • Procedures (e.g., a Management of Change pro­ gram) to ensure that components added to each facility during maintenance and construction are evaluated to determine if they are subject to LDAR requirements, and that affected components are integrated into the LDAR program. W i thin thir t y

(30) d a y s aft e r d e velop i ng th e wr i t

t e n faci l i t y-wi d e LDAR pr ogr a m , s ubmi ta c o p y o f th e P r ogr a m to EP A and to th e ap pr opri at e s t at e ag e n cy . 7.2 T raining A tr aining pr ogr a m wi l lpr ovi d e LDAR p e rs onn e l th e t e chnical und e rs tand ing to make th e wr i tt e n LDAR pr ogr a m w o rk. Ital s o wi l leducat e m e mb ers o f

th e LDAR t eam on th eir ind ivi dual r e s p ons i b i l i

ti es. Th ese tr aining pr ogr a ms can var y acc o r ding to th e l e vel o f in v o lvem ent and d e gr ee o f r e s p ons i b i l i t y of

L D AR p e r s o n n e l
. Elements: • Provide and require initial training and annual LDAR refresher training for all facility employees assigned LDAR compliance responsibilities, such as monitoring technicians, database users, QA/QC personnel, and the LDAR Coordinator; • For other operations and maintenance personnel with responsibilities related to LDAR, provide and require an initial training program that includes instruction on aspects of LDAR that are relevant to their duties (e.g., operators and mechanics per­ forming valve packing and unit supervisors that approve delay of repair work). Provide and require “refresher” training in LDAR for these personnel at least every three years. • Collect training information and records of contrac­ tors, if used.

20Leak Detection and Repair—A Best Practices Guide

7.3 LDAR Audits Wh eth e r LDAR moni toring i s don e in house or c o ntr a ct ed to thir d par t i e s outs i d e th e c o mpan y

, th e p o t e nti al exi s ts for LDAR s t aff not to ad h e r e c o rr ectl y to th e LDAR pr ogr a m . I n t e rnal and thir d-par t y

audi t s o f a faci l i t y LDAR pr ogr a m ar e a cri t ical c o mp on ent o f eff ective LDAR pr ogr a ms. Th e audi t s ch eck that th e c o rr ect equipm ent i s b e ing moni tor ed , M e thod 21 pr o c edur es ar e b e ing fol l owed , l e ak s ar e b e ing fi xe d , and th e r e quir ed r e c o r d s ar e b e ing ke pt. I nshor t, th e audi t s ens u r e that th e LDAR pr ogr a m i s b e ing c o nduct e d c o r r e ctl y

and pr obl e ms ar e i d e ntifi ed and c o rr e c t e d
. Elements: • Review records on a regular cycle to ensure that all required LDAR-related records, logs, and databases are being maintained and are up to date. • Ensure and document that the correct equipment is included in the LDAR program and that equipment identifi ed as leaking is physically tagged with the equipment ID number

. • Observe the calibration and monitoring techniques used by LDAR technicians, in particular to ensure the entire interface is checked and the probe is held at the interface, not away from the interface. • Retain a contractor to perform a third-party audit of the facility LDAR program at least once every four (4) years. • Perform facility-led audits every four (4) years.

– Use personnel familiar with the LDAR program and its requirements from one or more of the company’ s other facilities or locations (if available).

– Perform the fi rst round of facility-led LDAR audits no later than two (2) years after completion of the third-party audits outlined above, and every four (4) years thereafter

.
– This rotation ensures that the facility is being audited once every two (2) years. • If areas of noncompliance are discovered, initiate a plan to resolve and document those issues. • Implement, as soon as practicable, steps necessary to correct causes of noncompliance, and prevent, to the extent practicable, a recurrence of the cause of the noncompliance. • Retain the audit reports and maintain a written record of the corrective actions taken in response to any defi ciencies identifi ed.

217.4 Contractor Accountability C o ntr a ctors p e r f ormin g monitorin g ar e fr equ e ntl y c o mp ensat e d for th e numb er o f c o mp on ents th ey moni tor , wh ich might pr ovi d e an incentive to r u sh thr o ugh moni toring pr o c edur es and not ad h e r e to M e thod 21 r e quir em ents for r e s p onse tim e, monitoring di s t ance, etc. I f thi s hap p ens, s o m e equipm e nt l e ak s ma y not b e d e t e ct ed
. T o over c o m e thi s p o t e nti al pr obl e m , faci l i t i e s shoul dha ve in pl ace su ffi ci ent overs ight pro c edur e s to incr ease th e acc ount abi lit y o f c o ntr a ctors. Elements: • Write contracts that emphasize the quality of work instead of the quantity of work only

. • Require contractors to submit documentation that their LDAR personnel have been trained on Method 21 and facility-specifi c LDAR proce­ dures. • Ensure that the contractor has a procedure in place to review and certify the monitoring data before submitting the data to the facility

. • Review daily results of contractor work to en­ sure that a realistic number of components are being monitored. • Perform spot audits in the fi eld to ensure that Method 21 procedures are being followed. This can include spot-checking monitored components with another hydrocarbon analyzer or following LDAR personnel as they perform monitoring. • Have periodic reviews of contractor perfor­ mance (e.g., quarterly or semi-annually) to resolve issues and correct problems. Leak Detection and Repair—A Best Practices Guide

7.5 Internal Leak Defi nition for V alves and Pumps Th e var ying l e ak d e fi nitions that can appl y to di ff er ent pro c e s s units and c o mp on ents can b e c o nfus in g and l e ad to errors in prop erl y

i d e ntifyi n g l e ak s. T o c ount e r thi s p o t e nti al pr obl e m , op er at e y our LDAR pr ogr a m us ing an int e rnal l e ak d e finition for valve s and pumps in light li qui dor gas vap o r ser vi ce. Th e int e rnal l e ak d e fi nition w o ul d b e equival e nt to or lower than th e ap pl icabl e d e finitions in y our p e rmit and th e applicabl e fed e r al , s t at e, and lo cal r e gul ations. M o nitorin g a g ains t a uniform d e fi nition that i s lowe r than th e applicabl e r e gul ator y d e fi nition wi l lr e duc e errors and provi d e a margin o f saf e t

y

for i d e ntifying l e aking c o mp on e nts. Th e int e rnal l e ak d e fi nition w o ul d appl y to val ve s and pumps ( a nd p o s s i bl y c o nn e ctors ) in light l i qui dor g a s vap o r ser vi ce.

Elements: • Adopt a 500-ppm or lower internal leak defi nition for VOCs for all valves in light liquid and/or gas vapor service, excluding pressure relief devices. • Adopt a 2,000-ppm or lower internal leak defi nition for pumps in light liquid and/or gas/vapor service. • Record, track, repair, and monitor leaks in excess of the internal leak defi nition. Repair and monitor leaks that are greater than the internal leak defi nitions but less than the applicable regulatory leak defi nitions within thirty (30) days of detection.

Consent Decrees between EP A and many chemical facilities subject to the HON require using a 250-ppm leak defi nition for valves and connectors and a 500­ ppm leak defi nition for pumps. Note: If a state or local agency has lower leak defi nitions, then the internal leak defi nition should be set to the lowest defi nition or even lower to include/allow for margin of error

. 22Leak Detection and Repair—A Best Practices Guide

7.6 More Frequent Monitoring M a ny r e gul ations al low for l e s s fr equ e nt monitor

ing ( i .e. skip p e riod s ) wh en go od p e r f ormance ( a s de fi n e d in th e applicabl e r e gul ation ) i s d e mons t r at e d
. S kip p e riod i s an al t e rnative w o rk pr actice found in s o m e equipm ent l e ak r e gul ations and us ual l y appli e s onl y

to val ve s and c o nn e ctors. Af t e r a s p ecifi ed numb er o f l e ak d e t e ction p e rio d s (e.g., monthl y

) during wh ich th e p e r c entag e o f l e aking c o mp on ents i s b e low a cer t ain valu e (e.g., 2% for N S P S faci l i t i e s ), a faci l i t y can moni tor l e s s fr equ entl y (e.g., quar t e rl y

) as long as th e p e r c entag e o f

l e aking c o mp on ents r e mains low
. Th e faci l i t y mus tke e p a r e c o r do f th e p e r c entag e o f th e c o mp on e nt t y

p e found l e akin g durin g each l e ak d e t e ction p e riod
. E x p e ri ence has shown that p o o r moni toring r ath er than go od p e r f ormance has al lowed faci l i t i e s to take ad vantag e o f th e l e s s fr equ e nt moni toring pr ovi s ions. T o ens u r e that l e ak s ar e s t i l lb e ing ide n t ifi ed in a tim e l y

mann er and that pr e viousl y u n ide n t ifi ed l e ak s ar e not w o rsening over tim e, impl em ent a pl an for mor e fr equ e nt monitorin g for c o mp on ents that c o ntri but e mo s tto equipm ent l e ak emi s s ions. Elements: • Monitor pumps in light liquid and/or gas vapor service on a monthly basis. • Monitor valves in light liquid and/or gas vapor service – other than diffi cult-to-monitor or unsafeto-monitor valves – with no skip periods.
Consent Decrees between EP A and many chemical facilities subject to the HON require semiannual monitoring of connectors. 7.7 Repairing Leaking Components T

o s t op d e t e ct ed l e ak s wh i l e th ey ar e s t i l ls m al l , mo s tr ul e s r e quir e a fi rs t at t e mpt at r e pair wi thin 5 d a y s o f th e l e ak d e t e ction and a fi nal r e pair wi thin 15 d a y s. H o we ve r , an y c o mp on ent that cannot b e r e pair ed wi thin tho s e tim e fr am e s mus tb e pl aced on a “ D el a y

o f Re pair” l i s tto b e r e pair ed during th e n e xt shut downc ycl e. F i rs t att e mpts at r e pair includ e, but ar e not l i mi t e d to, th e fol l owing b e s tpr actic e s wh er e pr acticabl e and ap pr opri at e:

• Tight e ning b o nn et b o l t s;
• Re pl acing b o nn et b o l t s;
• Tight e ning packing gl and nuts; and
• I n jecting lubricant into lubricat ed packing.
Elements: • Schedule the “fi rst attempt at repair” of those components that the monitoring personnel are not authorized to repair consistent with the existing regulatory requirements. • Monitor the component for which a “fi rst attempt at repair” was performed no later than the next regular business day to ensure the leak has not worsened. • If the fi rst attempt at repair has not succeeded then other methods, such as “drill and tap” should be employed where feasible. Drill and tap procedures are no longer considered extraordinary practices.

237.8 Delay of Repair Compliance Assurance An y c o mp on ent that cannot b e r e pair ed durin g th e sp e c i fi ed r e pair int e r val mus tb e pl aced on a “ D el a y o f

Re pair” l i s tto b e r e pair ed during th e n e xt shutdowncycl e. D e l a y o f r e pair c o mpl i ance as s u r a nce pro c edur e s ens u r e that th e ap propri at e equipm ent i s jus t ifi abl y

on th e “ D el a y

o f Re pair” l i s tand that faci l i t i e s ha ve a pl an to fix th ese c o mp on ents.
Elements: • Have the unit supervisor approve in advance and certify all components that are technically infeasible to repair without a process unit shut­ down. • Continue to monitor equipment that is placed on the “Delay of Repair” list in the facility’ s regular LDAR monitoring. For leaks above the internal leak defi nition rate and below the regulatory rate, put the equipment on the “Delay of Repair” list within 30 days. • Implement the following repair policies and procedures within 15 days of implementing the written LDAR program:

– For valves, other than control valves or pressure relief valves, that are leaking at a rate of 10,000 ppm or greater and cannot be feasibly repaired without a process unit shutdown, use “drill and tap” repair methods to fi x the leaking valve, unless you can determine and document that there is a safety, mechanical, or major environmental concern posed by repairing the leak in this manner

.
– Perform up to two “drill and tap” repair attempts to repair a leaking valve, if necessary, within 30 days of identifying the leak. Leak Detection and Repair—A Best Practices Guide

7.9 Electronic Monitoring and Storage of LDAR Data El ectr onic moni toring and s tor ag e o f LDAR d ata wi l lh e lp e valuat e th e p e r f ormance o f moni tor

ing p e rs onn e l ( vi a tim e/d at e s t amps ), impr ove accur a cy , pr ovi d e an eff ective m eans for QA/Q C, and r e tri e ve r e c o r d s in a tim e l y

mann er for r e vi e w purp o s es. I n c o rp or at e and maintain an el ectr onic d atabase for s toring and r e p o r t ing LDAR d ata . U s e d at a logg ers or oth e r d at a c o l l e ction d e vi c e s durin g al l LDAR moni toring.
Elements: • Use best efforts to transfer, on a daily basis, electronic data from electronic data logging devices to the database. • For all monitoring events in which an electronic data collection device is used, include a time and date stamp, operator identifi cation, and instrument identifi cation. • Paper logs can be used where necessary or more feasible (e.g., small rounds, re-monitoring fi xed leaks, or when data loggers are not available or broken), and should record, at a minimum, the monitoring technician, date, and monitoring equipment used. • Transfer any manually recorded monitoring data to the database within 7 days of monitoring. • Review records to identify “problem” componentsfor preventative maintenance (repair prior to anticipated failure) or for replacement with “leakless” technology

.

24Leak Detection and Repair—A Best Practices Guide

7.10 QA/QC of LDAR Data QA/Q C audi t s ens u r e that M e thod 21 pr o c edur es ar e b e in g fo l l owed and LD AR p e rs onn e l ar e monitoring th e c o rr ect c o mp on ents in th e pr op er mann e r. D e ve lop and impl em ent a pro c edur e to ens u r e QA/Q C r e vi e w o f al l d ata g e n e r at e d b y LDAR moni toring t e chnici ans on a d ai l y bas i s or at th e c o nclus ion o f each moni toring e p i s od e.
Elements: Some QA/QC procedures include: • Daily review/sign-off by monitoring technicians of the data they collected to ensure accuracy and validity

. • Periodic review of the daily monitoring reports generated in conjunction with recordkeeping and reporting requirements. • Quarterly QA/QC of the facility’ s and contractor ’ s monitoring data including:

– Number of components monitored per technician;

– Time between monitoring events; and

– Abnormal data patterns. 7.11 Calibration/Calibration Drift Assessment A

lwa y s cal i br at e LDAR moni toring equipm ent usin g an appropri at e cali br ation gas, in ac c o r d anc e wi th 40 C F R P ar t60, EP A Ref e r e nce T e s tM e thod 21.

Elements: • Conduct calibration drift assessments of LDARmonitoring equipment at the end of each monitoring shift, at a minimum. • Conduct the calibration drift assessment using, ata minimum, approximately 500 ppm of calibration gas. • If any calibration drift assessment after the initial calibration shows a negative drift of more than 10% from the previous calibration, re-monitor allvalves that were monitored since the last calibration with a reading of greater than 100 ppm. Re-monitor all pumps that were monitored since the last calibration with a reading of greater than 500 ppm.

25Leak Detection and Repair—A Best Practices Guide

7.12 Records Maintenance O rg a ni zed and r e ad i l y a vai l abl e r e c o r d s ar e on e p o t e nti al indication o f an eff ective LDAR pr ogr a m . W e l l-ke p t r e c o r d s ma y al s o indi cat e that th e LDAR pr ogr a m i s int e gr at ed into th e faci l i t y ’s r o utin e op er ation and mana gem e nt. Th e equipm ent l e ak r e gul ations s p e c ify r e c o r d ke e p in g and r e p o r t in g r e quir em ents; inc o rp or atin g th e el em ents b e low wi l lh e lp ens u r e y our faci l i t y LDAR r e c o r d s ar e thorou gh and c o mpl e t e .
Elements: (4) The number of valves and pumps found leaking; Records to maintain: (5) The number of “diffi cult to monitor” pieces • A certifi cation that the facility implemented the of equipment monitored; “fi rst attempt at repair” program. (6) A list of all equipment currently on the • A certifi cation that the facility implemented “Delay of Repair” list and the date each QA/QC procedures for review of data generated component was placed on the list; by LDAR technicians. (7) The number of repair attempts not com­ • An identifi cation of the person/position at each pleted promptly or completed within 5 facility responsible for LDAR program perfor

­ days; mance as defi ned in the written program. (8) The number of repairs not completed • A certifi cation that the facility developed and within 30 days and the number of compo- implemented a tracking program for new nents not placed on the “Delay of Repair” valves and pumps added during maintenance list; and and construction defi ned in the written pro­ (9) The number of chronic leakers that do not gram. get repaired. • A certifi cation that the facility properly completed calibration drift assessments. • Records of audits and corrective actions. Prior to the fi rst third-party audit at each facility, • A certifi cation that the facility implemented the include in your records a copy of each audit “delay of repair” procedures. report from audits conducted in the previous • The following information on LDAR monitoring: calendar year and a summary of the actions (1) The number of valves and pumps present planned or taken to correct all defi ciencies in each process unit during the quarter; identifi ed in the audits. (2) The number of valves and pumps moni- • For the audits performed in prior years, identored in each process unit; tifi cation of the auditors and documentation (3) An explanation for missed monitoring if that a written plan exists identifying corrective the number of valves and pumps present action for any defi ciencies identifi ed and that exceeds the number of valves and pumps this plan is being implemented. monitored during the quarter;

26Leak Detection and Repair—A Best Practices Guide 

## 8.0 Sources of Additional Information

I n s p e ction M a nual: F e d e r al E quipm ent L e ak Regul ations for th e Ch emical M a nufacturin g I n dus t r y , EP A/305/B-98/011, D e cemb er 1998. http://cfpub.e pa .gov/c ompli a nc e/r e s ource s/publications/as s i s t ance/se ctors/ch e mical/ind ex.cfm V

o l 1: I n s p e ction M a nual ht

t p://www .e pa .gov/c ompli a nce/r e s ource s/publ ications/as s i s t a nce/se ctors/ins man v o l1.pdf V

o l 2: Ch emical M a nufacturin g I n dus t r y Regul ations (3 p ar t s on th e I n t e rn et) ht

t p://www .e pa .gov/c ompli a nce/r e s ource s/publ ications/as s i s t a nce/se ctors/ins man v o l2pt1.pdf ht

t p://www .e pa .gov/c ompli a nce/r e s ource s/publ ications/as s i s t a nce/se ctors/ins man v o l2pt2.pdf ht

t p://www .e pa .gov/c ompli a nce/r e s ource s/publ ications/as s i s t a nce/se ctors/ins man v o l2pt3.pdf V

o l 3: P e tr ol eum Refi nin g I n dus t r y Regul ations ht

t p://www .e pa .gov/c ompli a nce/r e s ource s/publ ications/as s i s t a nce/se ctors/ins man v o l3.pdf 1995 P r oto c ol for Equipm ent L e ak Emi s s ion Es timat e s , EP A-453/R -95-017, N o v 1995. ht

tp://www .e pa .gov/t tnchi e1/efdo c s/equipl k s.pdf Enfor c em ent A l er t, EP A O ffi ce o f Enforcem ent and C o mpli ance A s s u r a nce , EP A 300-N-99-014, O c t 1999. ht

tp://www .e p a .gov/c ompli a nc e/r e s ourc e s/n e w sl et t e rs/civi l/enfal er t/emi s s ions.p df N ational P e tro l eum Refi n e r y I n i t i ative , EP A. http://www .e pa .gov/c ompl i a nce/r es our ces/cases/civi l/caa/r efi n e r yini t i ative032106.pdf P e tr ol eum Refi n e r y I n i t i ative F a ct S h eet , EP A. http://www .e pa .gov/c ompl i a nce/r es our ces/cases/civi l/caa/p etr o l e umr efi n e r y-fcsht.html P e tr ol eum Refi n e r y N ational P r iorit y Case Re s ults
. ht

tp://www .e pa .gov/c ompl i a nce/r es our ces/cases/civi l/caa/oi l / D r aft St aff Re p o r t, Regul ation 8, Rul e 18, E quipm ent L e ak s, Ba y Ar ea A i r Qu alit y M a na gem e nt D i s t rict , Jul 1997. ht

tp://www .baaqmd .gov/pln/r ul ed e v/8-18/1997/0818_s r_071097.pdf Stand ar d s o f P e r f ormance for Equipm ent L e ak s o f VO C in th e Synth etic O rg a nic Ch emical s M a nu­ facturing I n dus t r y ; Stand ar d s o f P e r f ormance for Equipm ent L e ak s o f VO C in P e tr ol eum Refi n e ri es; P r op o sed Rul e , [EP A-HQ-OAR -2006-0699; F RL- ] RIN 2060-AN71. ht

tp://www .e pa .gov/ttn/oarpg/t3/f r_notices/equip_l eak_pr o p103106.pdf I n dus t ri al O rg a nic Ch emical s Compl i ance I n centive P r ogr a m , EP A Compl i ance and Enfor c em ent. ht

tp://www .e pa .gov/c ompl i a nce/i ncentives/pr o gr ams/io c cip.html
27Leak Detection and Repair—A Best Practices Guide

L e ak D e t e ction and Re p air P r ogr a m D e ve lopm ents . http://www .e pa .gov/c ompl i a nce/n eic/fi el d/l eak.html C o mpli anc e and Enforc em ent An nual Re s ults: I mp o r t ant En vi ronm ent al P r o b l e ms / N ational P r ioriti e s . http://www .e pa .gov/c ompl i a nce/r es our ces/r e p o r t s/end o f year/e oy2006/s p-air to xics-natl-priori t i e s.html P o r t abl e I n s t r u m e nts U ser’s M a nual F o r M o ni toring VO C S our ces , EP A-340/1-86-015. I n s p e ction T e chni qu e s F o r Fu gitive VO C Emi s s ion S ource s, EP A 340/1-90-026a ,d ,e,f (r e v M a y 1993) C ourse #380. En vironm ental c o mpl i anc e a s s i s t anc e r e sourc e s can b e found at:

ht

tp://cfpub.e pa .gov/cl earinghouse/ htt p://www .as s i s tancecent e rs.n et/ ht

t p://www .e pa .gov/c ompli a nce/as s i s t a nce/se ctors/ind ex.html

28Leak Detection and Repair—A Best Practices Guide 

## Appendix A Federal Regulations That Require a Formal LDAR Program W ith Method 21

Part 40 CFR Subpart Regulation T itle 60 VV SOCMI VOC Equipment Leaks NSPS 60 DDD Volatile Organic Compound (VOC) Emissions from the Polymer Manufacturing Industry 60 GGG Petroleum Refi nery VOC Equipment Leaks NSPS 60 KKK Onshore Natural Gas Processing Plant VOC Equipment Leaks NSPS 61 J National Emission Standard for Equipment Leaks (Fugitive Emission Sources) of Benzene 61 V Equipment Leaks NESHAP 63 H Organic HAP Equipment Leak NESHAP (HON) 63 I Organic HAP Equipment Leak NESHAP for Certain Processes 63 J Polyvinyl Chloride and Copolymers Production NESHAP 63 R Gasoline Distribution Facilities (Bulk Gasoline T erminals and Pipeline Breakout Stations) 63 CC Hazardous Air Pollutants from Petroleum Refi neries 63 DD Hazardous Air Pollutants from Off-Site W aste and Recovery Operations 63 SS Closed Vent Systems, Control Devices, Recovery Devices and Routing to a Fuel Gas System or a Process 63 TT Equipment Leaks – Control Level 1 63 UU Equipment Leaks – Control Level 2 63 YY Hazardous Air Pollutants for Source Categories: Generic Maximum Achievable Control T echnology Standards 63 GGG Pharmaceuticals Production 63 III Hazardous Air Pollutants from Flexible Polyurethane Foam Production 63 MMM Hazardous Air Pollutants for Pesticide Active Ingredient Production 63 FFFF Hazardous Air Pollutants: Miscellaneous Organic Chemical Manufacturing 63 GGGGG Hazardous Air Pollutants: Site Remediation 63 HHHHH Hazardous Air Pollutants: Miscellaneous Coating Manufacturing 65 F Consolidated Federal Air Rule – Equipment Leaks 264 BB Equipment Leaks for Hazardous W aste TSDFs 265 BB Equipment Leaks for Interim Status Hazardous W aste TSDFs Note: Many of these regulations have identical requirements, but some have different applicability and control requirements.

29Leak Detection and Repair—A Best Practices Guide 

## Appendix B Federal Regulations That Require the Use of Method 21 But Do Not Require a Formal LDAR Program 40 CFR Regulation T itle Part Subpart 60 XX Bulk Gasoline T erminals 60 QQQ VOC Emissions from Petroleum Refi nery W astewater Systems 60 WWW Municipal Solid W aste Landfi lls 61 F Vinyl Chloride 61 L Benzene from Coke By-Products 61 BB Benzene Transfer 61 FF Benzene W aste Operations 63 G Organic Hazardous Air Pollutants from SOCMI for Process Vents, Storage Vessels, Transfer Operations, and W astewater 63 M Perchloroethylene Standards for Dry Cleaning 63 S Hazardous Air Pollutants from the Pulp and Paper Industry 63 Y Marine Unloading Operations 63 EE Magnetic T ape Manufacturing Operations 63 GG Aerospace Manufacturing and Rework Facilities 63 HH Hazardous Air Pollutants from Oil and Gas Production Facilities 63 OO T anks – Level 1 63 PP Containers 63 QQ Surface Impoundments 63 VV Oil/W ater , Organic/W ater Separators 63 HHH Hazardous Air Pollutants from Natural Gas T ransmission and Storage 63 JJJ Hazardous Air Pollutant Emissions: Group IV Polymers and Resins 63 VVV Hazardous Air Pollutants: Publicly Owned Treatment W orks 65 G C F AR – Closed Vent Systems 264 AA Owners and Operators of Hazardous W aste T reatment, Storage, and Disposal Facilities - Process Vents 264 CC Owners and Operators of Hazardous W aste T reatment, Storage and Disposal Facilities - T anks, Surface Impoundments, Containers 265 AA Interim Standards for Owners and Operators of Hazardous W aste Treatment, Storage, and Disposal Facilities – Process Vents 265 CC Interim Standards for Owners and Operators of Hazardous W aste Treatment, Storage, and Disposal Facilities - T anks, Surface Impoundments, Containers 270 B Hazardous W aste Permit Program – Permit Application 270 J Hazardous W aste Permit Program – RCRA Standardized Permits for Storage T

anks and Treatment Units

30Leak Detection and Repair—A Best Practices Guide 

## Appendix C Method 21 General Procedure

F ai l ur e o f faci l i t i e s to fol l ow M e thod 21 can l e ad to th em not pr op erl y

i d e ntifying and s ubsequ e ntl y

r e pairing l e aking c o mp on ents. Iti s cri t ical for faci l i t i e s to r e f e r to th e c o mpl e t e t e xt o f M e thod 21 ( s ee A p p e ndix D) for d e t ai l ed e x pl anations o f each gen e r al pro c edur e found b e low and how to prop erl y

p e r f orm each s t e p. 1. E valuat e I n s tr u m e nt P e r formanc e Per f

o r

man c e criteriafo r the mo nito ring in st rument:

• F o r each VO C m e as ur ed , th e r e s p onse factor shoul db e <10 unl e s s sp e c i fi ed in th e ap pl icabl e r e gul a tion
. Re s p onse factor i s th e r atio o f th e known c o nc entr ation o f a VO C c o mp ound to th e obser ved m e t e r r e adin g wh en m e as ur ed us in g an ins t r u m e nt cali br at ed wi th th e re f e re n c e c o mp o u n ds p e c i fi ed in th e applicabl e r e gul ation
. •Th e cali br ation pr e c i s ion shoul db e <10 p e rcent o f th e cali br ation g a s valu e. Cali br ation pr e c i s ion i s th e d e gr ee o f agr e em ent b e t ween m e as u r e m e nts o f th e sam e kn own valu e, ex p r es s e das t h e r e lat ive pe r c e n tag e o f

th e a ver ag e d i ff er ence b e t ween th e m e t e r r e adings and th e kn own c o nc entr ation to th e known c o nc entr ation
. •Th e r e s p onse tim e shoul db e ≤30 sec o nd s. Res p onse tim e i s th e tim e int e r val fr om a s t e p chang e in VO C c o nc entr ation at th e input o f

th e sampl i ng sy s t em to th e tim e at wh ich 90% o f th e c o rr es p o nding fi nal valu e i s r e ach e d as d i s p l a ye d on t h e i n s t ru me n tr e a d o utme te r. 2. Cal i b r at e I n s tr u m e nt B e

fo r eea ch mo nito ring epis od e:

• L e t th e ins t r u m e nt warm up.
• I n tro duc e th e cali br ation gas into th e ins t r u m e nt pr ob e.
• Adjus tth e ins t r u m e nt m e t e r r e adout to match th e cali br ation gas c o nc e ntr ation valu e. 3. M o nitor I n divi du al c o mp on ent s W

h en mo nito ring co mp o n ent s

:

• P l a ce th e pr ob e at th e s u r f ace o f th e c o mp on ent int e r f ace wh er e l e akag e co ul docc u r. • M o ve th e pr ob e along th e int e r f ace p e riph er y wh i l e obser vi ng th e ins t r u m e nt r e adout.
• L o cat e th e maximum r e ading b y movi ng th e pr ob e ar ound th e int e r fa c e . • Ke e p th e pro b e at th e lo cation o f th e maximum r e ading for 2 tim e s th e r e s p onse factor
. • I f th e c o nc entr ation r e adin g on th e ins t r u m e nt r e adout i s ab ove th e appli c abl e l e ak d e fi nition , th en th e c o mp on ent i s l e aking and mus tb e r e pair ed
. 31Leak Detection and Repair—A Best Practices Guide 

## Appendix D Method 21—Determination of V olatile Organic Compound Leaks
1.0 Scope and Application 1.1 An al yt e s. Analyte CAS No. Volatile Organic Compounds (VOC).......... No CAS number assigned. 1.2 S c op e. Th i s m e thod i s ap pl icabl e for th e d e t e rmination o f VO C l e ak s from pro c e s s equipm ent. Th ese s our ces includ e, but ar e not l i mi t e d to, valves, fl ang e s and oth e r c o nn ections, pumps and c o mpr e s s ors, pr e s s u r e r e li ef d e vi ces, pr o c es s dr ains, op en-end ed val ves, pump and c o mpr e s s or seal sy s t em d e g a ss i ng ve n t s, acc u m ulat o rves s e l ve n t s, agi t at o r seal s, and acces s do or seal s. 1.3 D ata Qu al i t y O bjectives. Ad h e r e nce to th e r e quir em ents o f thi s m e thod wi l lenhance th e qual i t y o f th e d ata obtain ed fr om air p o l l utant sampl i ng m e thod s. 2.0 Summary of Method 2.1 A p o r t abl e ins t r u m e nt i s used to d e t e ct VO C l e ak s fr om indivi dual s our ces. Th e ins t r u m e nt d e t e ctor t y

p e i s not s p e c ifi ed , but i tmus tm e et th e s p ecifi cations and p e r f or mance crit eri a c o nt ain e d in Se ction 6.0. A le ak de fi nition c o nc entr ation b a sed on a r e f e r e nce c o mp ound i s s p ecifi ed in each applicabl e r e gul ation . Th is me t h o dis i n te n d e d to lo cat e and cl as s i fy l e ak s onl y

, and i s not to b e used as a di r e ct m e as ur e o f mas s emi s s ion r at e from indivi dual s ource s. 3.0 Defi nitions 3.1 Cali br ation g a s m eans th e VO C c o mp ound used to adjus tth e ins t r u m e nt m e t e r r e ading to a kn own valu e. Th e cali br ation gas i s us ual l y th e r e f e r e nce c o mp ound at a kn own c o nc entr ation appro ximat el y equal to th e le ak de fi nition c o nc entr ation
. 3.2 Cali br ation pr e c i s ion m eans th e d e gr ee o f

a gr e em ent b e t ween m e as ur em ents o f th e sam e kn own valu e, expr es sed as th e r e l ative p e r c entag e o f th e a ver ag e d i ff er ence b e t ween th e m e t e r r e adings and th e kn own c o ncentr ation to th e known c o nc entr ation
. 3.3 L e ak d e fi nition c o nc entr ation m eans th e lo cal VO C c o nc entr ation at th e s u r f ac e o f a l e ak s our ce that indi cat e s that a VO C emi s s ion ( l eak ) i s pr esent. Th e le ak de fi nition i s an ins t r u m e nt m e t e r r e ading based on a r e f e r ence c o mp ound
. 3.4 N o d e t e ctabl e emi s s ion m eans a local VO C c o nc entr ation at th e s u r f ac e o f a l e ak s our ce, adjus t ed for lo cal VO C amb i ent c o ncentr ation , that i s l e s s than 2.5 % o f th e sp e c i fi e dle ak de fi nition c o nc entr ation . Th at indi cat e s that a VO C emi s s ion ( l eak ) i s not pr e sent.

32Leak Detection and Repair—A Best Practices Guide

3.5 Ref e r e nce c o mp ound m eans th e VO C s p eci e s sel e ct ed as th e ins t r u m e nt cali br ation b a s i s for sp e c i fi cation o f th e l e ak d e fi nition c o nc entr ation
. (F or exampl e, if a l e ak d e fi nition c o nc entr ation i s 10,000 p p m as m e than e, th en any s our ce emi s s ion that r e s ults in a lo cal c o nc entr ation that yi el d s a m e t e r r e ading o f 10,000 on an ins t r u m e nt m e t e r cal i br at ed wi th m e than e w o ul d b e cl as s i fi ed as a l e ak. I nthi s exampl e, th e l e ak d e fi nition c o nc entr ation i s 10,000 p p m and th e r e fer e nce c o mp ound i s m e than e.) 3.6 Re s p onse factor m eans th e r atio o f th e known c o nc entr ation o f a VO C c o mp ound to th e o b ser ve d m e t e r r e adin g wh en m e as ur ed us in g an ins t r u m e nt cal i br at ed wi th th e r e f e r e nce c o mp ound s p ecifi ed in th e applicabl e r e gul ation
. 3.7 Res p onse tim e m eans th e tim e int e r val fr om a s t e p chan ge in VO C c o nc entr ation at th e input o f th e sampl i ng sy s t em to th e tim e at wh ich 90 p e r cent o f th e c o rr es p o nding fi nal valu e i s r e ach e d as di s p l a ye d on th e ins t r u m e nt r e adout m e t e r. 4.0 Interferences [Reserved] 5.0 Safety 5.1 D i scl aim er. Th i s m e thod ma y in v o lve hazar d

ous mat e ri al s, op er ations, and equipm ent. Th is te s t m e thod ma y not ad dr es s al l o f th e saf e t

y

pr obl e ms as s o ci at ed wi th i t s use. Iti s th e r e s p ons i b i l i t y o f th e user o f thi s t e s tm e thod to es tabl i s h ap pr opri at e saf e t

y

and h e al th pr actices and d e t e rmin e th e applicabi lit y o f r e gul ator y limit ations prior to p e r forming thi s t e s tm e thod
. 5.2 H a zar d ous P o l l utants. Se ver al o f th e c o mp ound s, l e ak s o f wh ich ma y b e d e t e rmin ed b y thi s m e thod , ma y b e irri tating or c o rr o s ive to ti s s u e s (e.g., h e ptan e ) or ma y b e to xic (e.g., b e nzen e, m e thyl alc o hol). N earl y

al l ar e fi r e hazar d s. Comp ound s in emi s s ions shoul db e d e t e rmin ed throu gh fami li ar it

y wi th th e s ourc e. A p propri at e pr e c autions can b e found in r e fer e nce do cum e nts, s u ch as r e fer e nce N o. 4 in Se ction 16.0. 6.0 Equipment and Supplies A VO C moni toring ins t r u m e nt m e eting th e fol l owin g s p e c ifi cations i s r e quir ed: 6.1 Th e VO C ins t r u m e nt d e t e ctor shal l r e s p ond to th e c o mp ound s b e in g pro c e s sed . D e t e ctor t y

p e s that ma y m e et thi s r e quir em ent includ e, but ar e not limit e d to, cat al ytic o xi d ation , fl am e ioni z ation , infr ar ed abs o rption , and photoioni z ation
. 6.2 Th e ins t r u m e nt shal l b e capabl e o f m e as uring t h e le ak de fi nition c o nc entr ation s p e c ifi ed in th e r e gul ation
. 6.3 Th e scal e o f th e ins t r u m e nt m e t e r shal l b e r e ad abl e to ±2.5 % o f th e s p ecifi e dle ak de fi nition c o nc entr ation
. 6.4 Th e ins t r u m e nt shal l b e equip p ed wi th an el ectrical l y

driven pump to ens u r e that a sampl e i s provi d e d to th e d e t e ctor at a c o ns t a nt fl ow r at e. Th e nominal sampl e fl ow r at e, as m e as ur ed at th e sampl e pr ob e tip, shal l b e 0.10 to 3.0 l/min (0.004 to 0.1 ft 3 /min ) wh en th e pr ob e i s fi tt ed wi th a gl as s w o ol p l ug o rfi l t er that ma y b e used to pr e vent plugging o f th e ins t r u m e nt. 6.5 Th e ins t r u m e nt shal l b e equip p ed wi th a pr ob e or pr ob e ext e ns ion or sampl i ng not to exceed 6.4 mm ( 1/4 in ) in outs i d e di am et er , wi th a s i ngl e end op ening for admi s s ion o f sampl e.

33Leak Detection and Repair—A Best Practices Guide

6.6 Th e ins tr u m e nt shal l b eintrins i cal l y saf efor op er ation in ex plo s i veatmo sp h e re s as d e fi ne d by the National El e c trical C o d e by th e National Fi reP re vention A s s o ci ation or oth e r applicabl ere gul atory c o d e for op er ation in an y ex plo s i veatmo sp h e re s that ma y b eenc ount e re d in it s use. Th e ins tr u m e nt shal l , at a minimum , b eintrins i cal l y saf efor Cl as s 1, D i vi s ion 1 c o nditions, and/or Cl as s 2, D i vi s ion 1 c o nditions, as appr opri at e, as d e fi n e d by th e exampl e c o d e. Th e ins tr u m e nt shal l not b eop er at ed w ith an y saf e t

y d e vi ce, s u ch as an exhaus t fl am e arre s tor , re move d
. 7.0 Reagents and Standards 7.1 T w o g a s mixtur es ar e r e quir ed for ins t r u m e nt cali br ation and p e r f ormanc e e valuation : 7.1.1 Z e r o Gas. A i r

, l e s s than 10 par t s p e r mi l l ion b y v o lum e ( p pm v

) VO C. 7.1.2 Cali br ation Gas. F o r each org a nic s p e c i e s that i s to b e m e as ur ed during indivi dual s our ce s u r vey s, obtain or pr e p ar e a kn own s t and ar din air at a c o nc e ntr ation appro ximat el y equal to th e applicabl e le ak de fi nition s p e c ifi ed in th e r e gul ation
. 7.2 Cylind er Gase s. I f c ylind er cali br ation g a s mixtu r e s ar e used , th ey mus tb e anal yzed and cer t ifi ed b y th e manufactur er to b e wi thin 2 % accur a cy , and a sh elf l i f e mus tb e s p ecifi ed . Cylind er s t and ar d s mus tb e ei th er r eanal yzed or r e pl aced at th e end o f th e sp e c i fi ed sh elf l i f e. 7.3 P r e p ar ed Gase s. Cali br ation g a se s ma y b e pr e p ar ed b y th e user ac c o r din g to an y ac ce pt ed gase ous pr e p ar ation pro c edur e that wi l lyi el d a mi xtur e accur at e to wi thin 2 p e r c ent. P r e p ar ed s t and ar d s mus tb e r e pl aced each d a y o f use unl e s s it i s d e mons tr at ed that d e gr ad ation do e s not o c cur during s tor ag e. 7.4 Mixtur es wi th non-Ref e r e nce Comp ound Gases. Cali br ations ma y b e p e r f orm e d us in g a c o mp ound oth e r than th e r e f e r e nce c o mp ound
. I nthi s case, a c o n vers ion factor mus tb e d e t e rmin ed for th e alt e rnative c o mp ound s u ch that th e r e s ul t ing m e t e r r e adings during s our ce s u r vey s can b e c o n ver t e d to r e f e r e nce c o mp ound r e s ul t s. 8.0 Sample Collection, Preservation, Storage, and T ransport 8.1 I n s t r u m e nt P e r f ormance Evaluation . A s sembl e and s t ar t up th e ins t r u m e nt acc o r ding to th e manufactur er ’s ins t r u ctions for r e c o mm end e d warmup p e riod and pr el iminar y adjus t m e nts. 8.1.1 Re s p onse F a ctor. A r e s p onse factor mus tb e d e t e rmin ed for each c o mp ound that i s to b e m e as u r e d , ei th er b y t e s t ing or fr om r e f e r e nce s our ces. Th e r e s p onse factor t e s t s ar e r e quir ed b efor e pl acing th e anal yzer into ser vi ce, but do not ha ve to b e r e p e at ed at s ubsequ e nt int e r val s. 8.1.1.1 Cal i br at e th e ins t r u m e nt wi th th e r e f e r e nce c o mp ound as s p e c ifi ed in th e ap pl icabl e r e gul a tion . I n tro duc e th e cali br ation gas mixtur e to th e anal yzer and r e c o r dth e obser ved m e t e r r e ading. I n tr oduce zer o g a s unti l a s t abl e r e ading i s obtain ed
. M ake a total o f thr e e m e as ur em ents b y al t e rnating b e t we e n th e cali br ation gas and z e ro gas. Calcul at e th e r e s p onse factor for each r e p etition and th e a ver a g e r e s p onse factor
. 8.1.1.2 Th e ins t r u m e nt r e s p onse factors for each o f

th e ind ivi dual VO C to b e m e as ur ed shal l b e l e s s than 10 unl e s s oth e r wi s e s p ecifi ed in th e ap pl icabl e r e gul ation . Wh en no ins t r u m e nt i s a vai l abl e that m e ets thi s s p ecifi cation wh en cali br at ed wi th th e r e f e r e nce VO C s p ecifi ed in th e ap pl icabl e r e gul a 34Leak Detection and Repair—A Best Practices Guide

tion , th e a vai l abl e ins t r u m e nt ma y b e cali br at ed wi th on e o f th e VO C to b e m e as ur ed , or any oth e r VO C, s o long as th e ins t r u m e nt th en has a r e s p onse factor o f l e s s than 10 for each o f th e indivi dual VO C to b e m e as ur ed
. 8.1.1.3 A l t e rnative l y

, if r e s p onse factors ha ve b e en publ i s h e d for th e c o mp ound s o f int e r e s tfor th e ins t r u m e nt or d e t e ctor t y

p e, th e r e s p onse factor d e t e rmination i s not r e quir ed , and e xi s tin g r e s ults ma y b e r e f e r e nced . E x ampl es o f publ i s h e d r e s p onse factors for fl am e ioni z ation and cat al ytic o xi d ation d e t e ctors ar e includ ed in Refer e nce s 1–3 o f Se ction 17.0. 8.1.2 Cali br ation P r e c i s ion . Th e cali br ation pr e cis ion t e s tmus tb e c o mpl e t e d prior to pl acing th e anal yzer into ser vi ce and at s ubsequ e nt 3-month int e r val s or at th e n e xt use, wh ich e ver i s l at e r. 8.1.2.1 M ake a total o f thr e e m e as ur em ents b y al t e rnat e l y

us ing zer o g a s and th e s p ecifi ed cali br ation gas. Re c o r dth e m e t e r r e adin gs. Calcul at e th e a

ver ag e alg e br aic di ff er ence b e t ween th e m e t e r r e adings and th e kn own valu e. D ivi d e thi s a ver ag e di ff er enc e b y th e known cali br ation valu e and multipl y

b y 100 to expr e s s th e r e s ultin g cali br ation pr eci s ion as a p e r c entag e. 8.1.2.2 Th e cali br ation pr e c i s ion shal l b e equal to or l e s s than 10 % o f th e cali br ation gas valu e. 8.1.3 Resp onse T im e. Th e re sp onse tim et e st i sre quired b eforepl acin g th e instrum e nt into serv i ce. If a modifi cation to th e sampl epumping s yst em or fl ow co nfigura tion i smad e that wo ul d chan ge th e re sp onse tim e, a n ew t e st i sre quired b eforefurth e r use. 8.1.3.1 I n tr oduce zer o g a s into th e ins t r u m e nt sampl e pr ob e. Wh en th e m e t e r r e ading has s t ab i l i zed , s wi t ch quick l y to th e s p ecifi ed cali br ation g a s. Af t e r s wi t ching, m e as ur e th e tim e r e quir ed to attain 90 % o f th e fi nal s t abl e r e ading. P e r f orm thi s t e s tsequ e nce thr e e tim e s and r e c o r dth e r e s ul t s. Calcul at e th e a ver ag e r e s p onse tim e. 8.1.3.2 Th e ins t r u m e nt r e s p onse tim e shal l b e equal to or l e s s than 30 sec o nd s. Th e ins t r u m e nt pump, di lution pro b e ( i f any ), sampl e pro b e, and pro b e fi l t er that wi l lb e used during t e s t ing shal l al l b e in pl ac e durin g th e r e s p onse tim e d e t e rmination
. 8.2 I n s t r u m e nt Cali br ation . Cali br at e th e VO C monitorin g ins t r u m e nt ac c o r din g to Se ction 10.0. 8.3 I n divi dual S our ce Sur vey s. 8.3.1 T y

p e I—L eak D e fi nition Based on C o nc entr ation . P l a c e th e pro b e inl e t at th e s u r f ac e o f th e c o mp on ent int e r f ace wh er e l e akag e c o ul d o c cur. M o ve th e pr ob e along th e int e r f ace p e riph er y wh i l e o b ser vi n g th e ins t r u m e nt r e adout. I f an incr eased m e t e r r e ading i s obser ved , slowl y

sampl e th e int e r face wh er e l e akag e i s indi cat e d unti l th e maximum m e t e r r e ad ing i s obtain ed . L e a ve th e pr ob e inl e t at thi s maximum r e adin g lo cation for appro ximat el y t w o tim e s th e ins t r u m e nt r e s p onse tim e. I f th e maximum obser ved m e t e r r e ad ing i s gr eat e r than t h e le ak de fi nition in th e applicabl e r e gul ation , r e c o r dand r e p o r tth e r e s ul t s as s p ecifi ed in th e r e gul ation r e p o r t in g r e quir em ents. E x ampl e s o f th e application o f thi s gen e r al t e chni qu e to s p e c ifi c equipm ent t y

p e s ar e: 8.3.1.1 V alves. Th e mo s tc o mmon s our ce o f l e ak s fr om valves i s th e seal b e t ween th e s t em and housing. P l a ce th e pr ob e at th e int e r f ace wh er e th e s t em exi t s th e packing gl and and sampl e th e s t em cir

cumf er ence. A l s o, pl ace th e pr ob e at th e int e r f ace o f

th e packing gl and take-up fl an ge seat and sampl e

35th e p e riph er y . I nad dition , s u r ve y valve hous in gs o f mul t ipar t as sembl y at th e s u r f ace o f al l int e r f aces wh er e a l e ak c o ul d o c cur. 8.3.1.2 F l an ge s and O t h e r C o nn e ctions. F o r we l d e d fl ang e s, pl ace th e pr ob e at th e out e r edg e o f th e fl ang e-g aske t int e r f ace and sampl e th e cir c umf e r ence o f th e fl ang e. S a mpl e oth e r t y

p e s o f nonp er man e nt joints ( s uch as thr e ad ed c o nn e ctions ) wi th a s i mi l ar tr a verse. 8.3.1.3 Pumps and Compr e s s ors. Conduct a cir

cumf er enti al tr a verse at th e out e r s u r f ace o f th e pump or c o mpr e s s or shaft and seal int e r f ace. I f th e s ourc e i s a rot atin g shaft, p o s ition th e pro b e inl e t wi thin 1 cm o f th e shaft-seal int e r f ace for th e s u r vey . I f th e hous ing c o nfi gur ation pr e vents a c o mpl e t e tr a verse o f th e shaft p e riph er y , sampl e al l ac c e s s i b l e p o r tions. S a mpl e al l oth e r joints on th e pump or c o mpr e s s or hous ing wh er e l e akag e c o ul d occ u r. 8.3.1.4 P r es s u r e Rel i ef D e vi ces. Th e c o nfi gur ation o f

mo s tpr es s u r e r e l i ef d e vi ces pr e vents sampl i ng at th e seal i ng seat int e r f ace. F o r tho s e d e vi ces equip p ed wi th an enclo sed ext e ns ion , or horn , pl ace th e pr ob e inl e t at ap pr o ximat el y th e cent er o f th e exhaus t ar ea to th e atmo s p h e r e. 8.3.1.5 P r o c es s D r ains. F o r op en dr ains, pl ace th e pr ob e inl e t at ap pr o xima t e l y

th e cent er o f th e ar ea op en to th e atmo s p h e r e. F o r c o ver e d dr ains, pl ace th e pr ob e at th e s u r f ace o f th e c o ver int e r f ace and c o nduct a p e riph er al tr a verse. 8.3.1.6 O p en-end ed Lin e s or V alves. P l a ce th e pr ob e inl e t at ap pr o ximat el y th e cent er o f th e op ening to th e atmo s p h e r e. Leak Detection and Repair—A Best Practices Guide

8.3.1.7 Seal Sy s t em D e g a s s ing V e nts and A c cumul a tor V e nts. P l a ce th e pr ob e inl e t at ap pr o ximat el y th e cent er o f th e op ening to th e atmo s p h e r e. 8.3.1.8 A c ces s do or seal s. P l a ce th e pr ob e inl e t at th e s u r f ace o f th e do or seal int e r f ace and c o nduct a p e riph er al tr a verse. 8.3.2 T y

p e II—“ N o D e t e ctabl e Emi s s ion ”. D e t e r min e th e lo cal ambi ent VO C c o nc entr ation around th e s our ce b y movi ng th e pr ob e r a ndoml y

upwi nd and downwi nd at a d i s t ance o f on e to t w o m e t e rs from th e s ource. I f an int e r f er ence exi s ts wi th thi s d e t e rmination du e to a n earb y emi s s ion or l e ak, th e lo cal ambi ent c o nc entr ation ma y b e d e t e rmin ed at di s t ances clo ser to th e s our ce, but in no case shal l th e di s t ance b e l e s s than 25 centim et ers. Th en move th e pr ob e inl e t to th e s u r f ace o f th e s our ce and d e t e rmin e th e c o nc entr ation as outlin ed in Se ction 8.3.1. Th e di ff er ence b e t ween th e s e c o ncentr ations d e t e rmin e s wh eth e r th er e ar e no d e t e ctabl e emi s s ions. Rec o r dand r e p o r tth e r e s ul t s as sp e c i fi ed b y th e r e gul ation . F o r tho s e case s wh er e th e r e gul ation r e quir e s a s p e c ifi c device i n s t al la

tion , or that s p e c ifi ed vents b e duct ed or p ip e d to a c o ntro l d e vi c e, th e e xi s t e nc e o f th e s e c o nditions shal l b e vi s u al l y

c o nfi rm ed . Wh en th e r e gul ation al s o r e quir es that no d e t e ctabl e emi s s ions exi s t, vi s u al o b ser vations and samplin g s u r ve y s ar e r e quir ed . E x ampl es o f thi s t e chni qu e ar e: 8.3.2.1 Pump or Compr e s s or Seal s. I f ap pl icabl e, d e t e rmin e th e t y

p e o f shaft seal
. P e r f orm a s u r vey o f th e lo cal ar ea ambi ent VO C c o nc entr ation and d e t e rmin e if d e t e ctabl e emi s s ions exi s t as d e scri b ed in Se ction 8.3.2. 8.3.2.2 Seal Sy s t em D e g a s s ing V e nts, A c cumul ator V

e s s el V e nts, P r es s u r e Rel i ef D e vi ces. I f ap pl icabl e,

36Leak Detection and Repair—A Best Practices Guide

o b ser ve wh eth e r or not th e applicabl e ductin g or p ip i ng exi s ts. A l s o, d e t e rmin e if any s our ces exi s t in th e ducting or p ip i ng wh er e emi s s ions c o ul d o c cur ups t r eam o f th e c o ntr o l d e vi ce. I f th e r e quir ed ducting or p ip i ng exi s ts and th er e ar e no s our ces wh er e th e emi s s ions c o ul d b e vent ed to th e atmo s p h e r e ups t r eam o f th e c o ntr o l d e vi ce, th en i ti s pr es um ed that no d e t e ctabl e emi s s ions ar e pr esent. I f th er e ar e s our ces in th e ducting or p ip i ng wh er e emi s s ions c o ul d b e vent ed or s our ces wh er e l e ak s c o ul d o c cur , th e samplin g s u r ve y s d e scri b ed in Se ction 8.3.2 shal l b e used to d e t e rmin e if d e t e ctabl e emi s s ions exi s t. 8.3.3 A l t e rnative S c r e ening P r o c edur e. 8.3.3.1 A scr eening pr o c edur e based on th e formation o f bubbl e s in a s o ap s o lution that i s s p r a yed on a p o t e nti al l e ak s our ce ma y b e used for tho s e s our ces that do not ha ve c o ntinuousl y

movi ng par t s, that do not ha ve s u r f ace t e mp er atur es gr eat e r than th e b o i l ing p o int or l e s s than th e fr eezing p o int o f th e s o ap s o lution , that do not ha ve op en ar eas to th e atmo s p h e r e that th e s o ap s o lution cannot bri d ge, or that do not exhi b i te vi d e nce o f l i qui dl e akag e. S ourc e s that ha ve th e s e c o nditions pr e sent mus tb e s u r ve yed us in g th e ins t r u m e nt t e chni qu e o f Se ction 8.3.1 or 8.3.2. 8.3.3.2 Spr a y

a s o ap s o lution over al l p o t e nti al l e ak s our ces. Th e s o ap s o lution ma y b e a c o mm erci al l y a

vai l abl e l e ak d e t e ction s o lution or ma y b e pr epar e d us ing c o ncentr at ed d e t e rg ent and wat e r. A pr es s u r e s p r a ye r or squ e eze b o ttl e ma y b e used to di s p ense th e s o lution . O b ser ve th e p o t e nti al l e ak s i t e s to d e t e rmin e if any bubbl es ar e form ed . I f no bubbl e s ar e o b ser ve d , th e s ource i s pr e s um ed to ha ve no d e t e ctabl e emi s s ions or l e ak s as ap pl icabl e. I f any bubbl es ar e obser ved , th e ins t r u m e nt t e chni qu e s o f Se ction 8.3.1 or 8.3.2 shal l b e used to d e t e rmin e if a l e ak exi s ts, or if th e s our ce has d e t e ctabl e emi s s ions, as ap pl icabl e.

37Leak Detection and Repair—A Best Practices Guide

9.0 Quality Control

Section Quality control measure Effect 8.1.2....................................... Instrument calibration Ensure precision and accuracy , precision check. respectively , of instrument response to standard. 10.0........................................ Instrument calibration.

10.0Calibration and Standardization 10.1 Cal i br at e th e VO C moni toring ins t r u m e nt as fol l ow s. Af t e r th e ap pr opri at e warmup p e riod and z e ro int e rnal cali br ation pro c edur e, intro duc e th e cali br ation gas into th e ins t r u m e nt sampl e pro b e. Adjus tth e ins t r u m e nt m e t e r r e adout to c o rr es p o nd to th e cali br ation gas valu e. N o t e: I f th e m e t e r r e adout cannot b e adjus t ed to th e prop er valu e, a malfunction o f th e anal yz er i s indicat e d and c o rr e ctive actions ar e n e c e s s ar y b efor e use. 11.0 Analytical Procedures [Reserved] 12.0 Data Analyses and Calculations [Reserved] 13.0 Method Performance [Reserved] 14.0 Pollution Prevention [Reserved] 15.0 W aste Management [Reserved] 16.0References 1. D ub o s e, D .A., and G.E. H arri s. Res p onse F a ctors o f VO C An al yz ers at a M e t e r Reading o f 10,000 p p m v

for Sel e ct ed O rg a nic C o mp ound s. U
. S
. En vi ronm ent al P r ot e ction Ag enc y , Re sear ch T r i a n gl e P ark, NC. P ubl ication N o. EP A 600/2–81051. Se pt emb e r 1981. 2. B r own , G.E., et al . Re s p onse F a ctors o f VO C An al yzers Cal i br at ed wi th M e than e for Sel e ct ed O rg a nic Comp ound s. U
. S. En vi r o nm e nt al P r ot e ction Agenc y , Re search T r i a n gl e P ark, NC. P ublication N o. EP A 600/2–81–022. M a y 1981. 3. D u B o se, D .A. et al . Res p onse o f P o r t abl e VO C An al yzers to Ch emical Mixtur es. U
. S. En vi ronm ent al P r ot e ction Agenc y , Re search Tr i a n gl e P ark, NC. P ublication N o. EP A 600/2–81–110. Se pt emb e r 1981. 4. H a ndb o o k o f H a zar d ous M at e ri al s: F i r e, S af e t

y

, H e al th . A l l i ance o f Am erican I n s u r e rs. S c haumb e rg, IL. 1983. 17.0 T ables, Diagrams, Flowcharts, and Validation Data [Reserved]

38Leak Detection and Repair—A Best Practices Guide 

## Appendix E Summary of NEIC Comparative Monitoring Results of Leaking V alves at 17 Refi neries

Refi neries Total NEIC Total Valves Monitored 170,717 47,526 Number of Leaks 2,266 2,372

Leak Rate (%) 1.3 5.0 (avg) Emissions Rate (lb/hr) 1,177.0 2,775.5

Potential Emissions from Undetected Leaks (lb/ hr) a 1,598.5

Source: Enforcement Alert – Proper Monitoring Essential to Reducing ‘Fugitive Emissions’ Under Leak Detection and Repair Programs , EPA 300-N-99-014. US EPA Offi ce of Enforcement and Compliance Assurance. Vol. 2, No. 9, Oct 1999.

a Potential Emissions from Undetected Leaks (lb/hr) = NEIC T otal Emissions Rate (lb/hr)

–Refi neries T otal Emissions Rate (lb/hr)

39Leak Detection and Repair—A Best Practices Guide 

## Appendix F Enforcement Alert

40Leak Detection and Repair—A Best Practices Guide

41Leak Detection and Repair—A Best Practices Guide

42Leak Detection and Repair—A Best Practices Guide

43United States Environmental Protection Agency Offi ce of Compliance Offi ce of Enforcement and Compliance Assurance (mail code) EP A-305-D-07-001 October 2007 www .epa.gov/compliance