Final

— July 2, 2015

1 

## Significant New Alternatives Policy Program

Refrigeration and Air Conditioning Sector
Risk Screen on Substitutes in Cold Storage Warehouses and Industrial Process Refrigeration
Substitute: R

- 513A (Opteon® XP10)

This risk screen does not contain Clean Air Act (CAA) Confidential Business Information (CBI) and, therefore, may be disclosed to the public.



### 1. INTRODUCTION
Ozone

- depleting substances (ODS) are being phased out of production in response to a series of diplomatic and legislative efforts that have taken place over the past two decades, including the Montreal Protocol and the Clean Air Act Amendments of 1990 (CAAA). The U.S. Environmental Protection Agency (EPA), as authorized by Section 612 of the CAAA, administers the Significan t New Alternatives Policy (SNAP) Program, which identifies acceptable and unacceptable substitutes for ODS in specific end

- uses based on assessment of their health and environmental impacts. EPA’s decision on the acceptability of a substitute is based on the findings of a screening assessment of potential human health and environmental risks posed by the substitute in specific applications. EPA has already screened a large number of substitutes in many end

- use applications within all of the major ODS

usi ng sectors including: refrigeration and air conditioning, solvent cleaning, foam blowing, aerosols, fire suppression, adhesives, coatings and inks, and sterilization. The results of these risk screens are presented in a series of Background Documents that are available in EPA's docket. The purpose of this risk screen is to supplement EPA’s Background Document on the refrigeration and air conditioning sector (EPA 1994) (hereinafter referred to as the Background Document). This risk screen evaluates the poten tial use of R

- 513A (also known as Opteon® XP10) as a substitute in the cold storage warehouse s and industrial process refrigeration end

- use s . Table 1 presents the composition of the proposed substitute. Table 1 . Composition of R

- 5 13A and Potential Impurities
Constituent Chemical Formula CAS Number Concentration (Weight Percent) 2,3,3,3

- Tetrafluoropropene (HFO

- 1234yf) CH 2 CFCF 3 754

- 12

- 1 ≤56% 1,1,1,2

- Tetrafluoroethane (HFC

- 134a) CF 3 CH 2 F 811

- 97

- 2 ≤44% Potential Impurities

Section 2 summarizes the results of the risk screen for the proposed substitute blend listed in Table 1 . The remainder of the risk screen is organized into the following sections:

• Section 3 : Atmospheric Assessment

• Section 4 : Volatile Organic Compound Assessment

• Section 5 : Potential Health Effects

• Section 6 : Flammability Assessment

• Section 7: Asphyxiation Assessme n t

• Section 8 : Occupational Exposure AssessmentFinal

— July 2, 2015

2 • Section 9 : General Population Exposure Assessment

• Section 10 : References



### 2. SUMMARY OF RESULTS
R

- 513A is recommended for SNAP approval for cold storage warehouses and industrial process refrigeration . EPA's risk screen indicates that the use of the proposed substitute will be less harmful to the atmosphere than the continued use of ODS and other commonly used refrigerants, as it is less harmful to the ozone layer, has lower climate impact, and a shorter atmospher ic lifetime. The components of R

- 513A
are not subject to volatile organic compound (VOC) regulations under the CAA (40 CFR 51.100(s)), so environmental impact from the release of these substances is not a concern. In addition, because R

- 513A is considered to be nonflammable , the proposed substitute is not expected to present a flammability concern. It is expected that the manufacturer’s safety data sheet ( SDS) for R

- 513A and good manufacturing practices will be adhered to during handling or use of R

- 513A

. Additionally, it is expected that the appropriate safety and personal protective equipment (PPE) (e.g., protective gloves, tightly sealed goggles, protective work clothing, and suitable respiratory protection in case of leakage or insufficient ventilation) consistent with Occupational Safety and Health Administration (OSHA) guidelines will be used during manufacture, installation and servicing, and disposal of cold storage and industrial process refrigeration systems using R

- 513A . Because cold storage and i ndustrial process refrigeration systems are to be installed in locations with adequate space and/or ventilation in accordance with EPA recommendations and the equipment maintenance manuals for R

- 513A in each end

use, significant toxicity risk to consumers is also unlikely. Exposure at the end

- use is captured in the occupational exposure assessment , as consumer use of cold storage and industrial process refrigeration equipment is not anticipated

. I n addition, potential health risks from exposure to the prop osed substitute is considered to be a larger concern for workers than asphyxiat ion, 1 due to the large spaces in which these sys tems are installed and serviced. Therefore, an as phyxiation assessment was not conducted. Additional safeguards, including specified refrigerant concentration limits (RCL) of R

- 513A components, are also provided by adherence to industry standards including American Society of Heating, Refrigerating and Air

- Conditioning Engineers (ASHRAE) Standa rds 15, 2 34, 3 and 62. 4



### 3. ATMOSPHERIC ASSESSMENT This section presents an assessment of the potential risks to atmospheric integrity posed by the use of R

513A in cold storage warehouses and industrial process refrigeration . The ozone depletion potentia l (ODP), global warming potential (GWP), and atmospheric lifetime (ALT) of the proposed substitute are presented in Table 2

. The proposed substitute i s substantially less harmful to the ozone layer, has lower climate impact, and a shorter ALT when compared to CFC

- 12 and HCFC

- 22. In addition, R

- 513A also has lower climate impact and a shorter ALT than those predicted for other substitutes examined in the Background Document , as

1 The oxygen deprivation limit (ODL) for R

- 513A is 140,000 ppm per Sta ndard 34

- 2010 ( ASHRAE 2015 ). Exposure estimates remain significantly below this level (see Table 6). 2 Safety Standard for Refrigeration Systems ASHRAE Standard 15 establishes safeguards for life, limb, health, and property and prescribes safety requirements. 3 Designation and Safety Classification of R efrigerants ASHRAE Standard 34 establishes a uniform system for assigning reference numbers, safety classifications, and refrigerant concentration limits to refrigerants. Safety classifications bas ed on toxicity and flammability data are included. 4 Ventilation for Acceptable Indoor Air Quality ASHRAE Standard 62 establishes minimum ventilation rates and other measures intended to provide indoor air quality that is acceptable to human occupants and that minimizes adverse health effects.Final

— July 2, 2015

3 well as commonly utilized refrigerants HFC

- 134a, R

- 404A, and R

- 5 07 A . Thus , EPA believes that the use of R

- 513A would result in substantially less harm to the climate and oz one layer than the continued use of ODS and other commonly used refrigerants in cold storage and industrial process refrigeration systems

.

Table 2 . Atmospheric Impacts of R

- 513A Components Compared to Other Refrigerants Used in Cold Storage Warehouses and Industrial Process Refrigeration Refrigerant Ozone Depleting Potential (ODP) a Global Warming Potential (GWP) b Atmospheric Lifetime in Years (ALT) b R

- 513A 0 631 NA c Individual Components HFC

- 134a 0 1,430 14 HFO

- 1234yf 0 4 d 11 days d CFC

- 12 0.82 10,900 100 HCFC

- 22 0.13 1,810 12 a HFC

- 134a 0 1,430 14 R

- 404A e 0 3,922 NA f R

- 507A g 0 3,985 NA h

a WMO 2010 Scientific Assessment Report (2011) b IPCC 4 th Assessment Report (Forster et al. 2007)

c Atmospheric lifetimes are not given for blends, because the components separate in the atmosphere. The ALT for the individual components are also listed in Table 2

. d Papadimitriou et al. ( 2007 )

e R

- 404A is a blend consisting of HFC

- 143a (52%), HFC

- 125 ( 44%) and HFC

- 134a (4%). f Atmospheric lifetimes are not given for blends, because the components separate in the atmosphere. The ALT for HFC

- 143a is 52 years, the ALT for HFC

- 125 is 29 years, and t he ALT for HFC

- 134a is 14 years (IPCC 4 th Assessment Report [Forster et al. 2007]). g R

- 507A is a blend consisting of HFC

- 125 (50%) and HFC

- 143a (50%). h Atmospheric lifetimes are not given for blends, because the components separate in the atmosphere. The ALT for HFC

- 1 25 is 29 years and ALT for HFC

- 143a is 52 years (IPCC 4 th Assessment Report [Forster et al. 2007])


### 4. VOLATILE ORGANIC COMPOUND ASSESSMENT The components of R

- 513A (i.e., HFC

- 134a and HFO

- 1234yf ) , are exempt from the definition of VOCs under CAA regulations (40 CFR 51.100(s)). Therefore, VOC impacts from the release of R

- 513A are not a
concern.


### 5

. POTENTIAL HEALTH EFFECTS To assess potential health risks from exposure to the proposed substitute in cold storage warehouses and industrial process refrigeration , EPA identified the relevant toxici ty threshold values for comparison to modeled exposure concentrations for different scenarios. According to ASHRAE Standard 34

- 2013, R

513A is listed under safety group A1 with a RCL of 72,000 ppm (ASHRAE 2015) . ASHRAE 34 RCLs are intended to reduce the ri sks of acute toxicity, asphyxiation, and flammability hazards in normally occupied, enclosed spaces during refrigerant use and protect end

- users from the potential dangers of a catastrophic leak from a refrigeration unit (ASHRAE 2010b). ASHRAE Standard 15 implements the aforementioned standard, requiring that “the concentration of refrigerant in an enclosed space following a complete discharge of a high

- probability system shall not exceed the RCL” (ASHRAE 2010a). As such, this risk screen references the pro posed RCL for R

- 513A to ensure that significant end

- us e exposure risks do not occur. For the occupational exposure analysis, potential risks from chronic and acute worker exposure were evaluated by comparing exposure concentrations to available occupationa l exposure limits. Potential risks of chronic worker exposure were evaluated using workplace guidance levels (WGL) , such as Workplace Environmental Exposure Levels (WEELs)

. Risks from potential short

- term consumer exposures were evaluated by comparing exp osure concentrations to emergency guidance levels (EGL). In the absence ofFinal

— July 2, 2015

4 an established short

- term exposure limit (STEL), acute exposure guideline level (AEGL), or emergency response planning guideline (ERPG) for R

- 513A, potential short

- term end

- use expo sures were evaluated on a component basis (i.e., HFC

- 134a and HFO

- 1234yf). Table 3 lists the relevant toxicity limits for R

513A and its components , and is followed by Table 4 , which provides an explanation of each toxicity limit. EPA’s approach for iden tifying or developing these values is discussed in Chapter 3 of the Background Document.

Table 3 . Exposure Limits of R

- 513A Components
R

- 513A Component WGL (Long

- term Exposure)

ppm EGL (Short

- term Exposure) ppm Refrigerant Concentration Limit (RCL) ppm R

- 513A 653 (8

- hour AEL) 1,960 (15

- min STEL) a 72,000 Individual Components
HFC

- 134a 1,000 (8

- hour WEEL) 8,000 (10

- min AEGL

- 1) 8,000 (30

- min AEGL

- 1) 50,000 HFO

- 1234yf 500 (8

- hour WEEL) 1,500 (15

- min STEL) b 10 1 ,000 c

a Neither the American Conference of Governmental Industrial Hygienists ( ACGIH ) nor the American Industrial Hygiene Association ( AIHA ) recommend ceiling or short term exposure limits for the R

- 513A blend . A STEL for R

- 513A of 1,9 60 ppm was developed by EPA based on the 653 ppm acceptable e xposure limit ( AEL ) value. The STEL was estimated as three to five times the AEL, which is an established method of estimating a short

- term exposure limit by ACGIH. [STEL] = [AEL] x 3 = 653 ppm x 3 ≈ 1,960 ppm b Neither ACGIH nor AIHA recommend ceiling or short term exposure limits for HFO

- 1234yf. A STEL for HFO

- 1234yf of 1,500 ppm was developed by EPA based on the 500 ppm WEEL value. The STEL was estimated as three to five times the AEL, which is an established m ethod of estimating a short

- term exposure limit by ACGIH. [STEL] = [AEL] x 3 = 500 ppm x 3 ≈ 1,500 ppm

c Although an RCL has not been proposed for HFO

- 1234yf, the recommended ATEL for HFO

- 1234yf is 10 1 ,000 ppm (DuPont Fluoroproducts 2014).

Table 4 . Explan ation of Exposure Limit

- Related Terminology a

Organization Definition OSHA Occupational Safety and Health Administration NIOSH National Institute for Occupational Safety and Health ACGIH American Conference of Governmental Industrial Hygienists AIHA American Industrial Hygiene Association OARS Occupational Alliance for Risk Science Exposure Limit Definition Explanation Short

- Term Exposure RCL Refrigerant Concentration Limit The RCL for a refrigerant is intended to reduce the risks of acute toxicity, asphyxiation, and flammability hazards in normally occupied, enclosed spaces. The RCL for each refrigerant is the lowest of the Acute

- Toxicity Exposure Limit (ATEL), Oxygen Deprivation Limit (ODL), and Flammable Concentration Limit (FCL). Determi nation assumes full vaporization with no removal by ventilation, dissolution, reaction, or decomposition and complete mixing of refrigerant in the space to which it is released. ATEL Acute Toxicity Exposure Limit The ATEL is t he refrigerant concentration limit intended to r educe the risks of acute toxicity hazards in normally occupied, enclosed spaces according to ASHRAE Standard 34. The ATEL includes consideration of mortality, cardiac sensitization, anesthetic or central nervous system effects and other escape i mpairing effects and permanent injury. The ATEL is similar to the Immediately Dangerous to Life or Health (IDLH) concentrations set by NIOSH

. STEL Short

- Term Exposure Limit A 15

- minute time

- weighted average (TWA) exposure that should not be exceed ed during a workday, even if the 8

- hour TWA is within the threshold limit value

- time weighted average ( TLV

– TWA ) , set by ACGIH.Final

— July 2, 2015

5 AEGL b,c Acute Exposure Guideline Level 1 AEGL

- 1 is the airborne concentration (expressed as ppm or mg/m 3 ) of a substance above which it is predicted that the general population, including susceptible individuals, could experience notable discomfort, irritation, or certain asymptomatic nonsensory effects. However, the effects are not disabling and are transient and reversible upon cessation of exposure. Acute Exposure Guideline Level 2 AEGL

- 2 is the airborne concentration (expressed as ppm or mg/m 3 ) of a substance above which it is predicted that the general population, including susceptible individuals, coul d experience irreversible or other serious, long

- lasting adverse health effects or an impaired ability to escape. Acute Exposure Guideline Level 3 AEGL

- 3 is the airborne concentration (expressed as ppm or mg/m 3 ) of a substance above which it is predicted that the general population, including susceptible individuals, could experience life

- threatening health effects or death. Long

- Term Exposure PEL Permissible Exposure Limit This is an 8

- hour TWA exposure limit set by OSHA. AEL Acceptable Exposure Limit The maximum 8

- hour TWA at which a worker can be exposed regularly without adverse effects. WEEL Workplace Environmental Exposure Level Developed by OARS for to protect healthy workers against acute and chronic health effects, this limit is based on repeated daily exposures over a working lifetime and averaged over an 8

- hour workday. TLV

- TWA Threshold Limit Value

– Time

Weighted Average The TWA concentration for a conventional 8

- hour workday and a 40

- hour workweek, to which it is believed that nearly all workers may be repeatedly exposed, day after day, for a working lifetime without adverse effect according to ACGIH.

a All information in this table taken from EPA (1994) except where otherwise noted. b EPA (2012)

c A pplicable to emergency exposure periods ranging from 10 minutes to 8 hours. According to the SDS, exposure to R

- 513A may be hazardous if inhalation, skin contact, or eye contact with the substitute occurs. The most likely pathway of exposure is through inhalation. R

- 513 A can cause symptoms of asphyxiation when present in concentrations high enough to significantly lower oxygen concentrations below 19.5 percent by volume, s uch as headaches, ringing in ears, dizziness, drowsiness, nausea, vomiting, depression of all senses, and also unconsciousness. Under some circumstances of over

exposure (i.e., oxygen levels fall below 6 percent by volume), death may occur. If inhaled, R

- 513A can cause symptoms such as light

- headedness, dizziness, confusion, incoordination, drowsiness, unconsciousness, and anesthetic effects. Excessive inhalation of R

- 513A may also result in an irregular heartbeat or death, due to cardiac effects. Furtherm ore, R

- 513A vapors are denser than air and can cause asphyxiation if the oxygen concentration in a room is significantly reduced. If R

- 513A is inhaled, person(s) should be immediately removed from the contaminated space and exposed to fresh air. In accor dance with the SDS, EPA further recommends that if breathing is difficult or irregular, person(s) should be given oxygen, provided a qualified operator is present, and medical attention be sought. Exposures of R

- 513A to the skin may cause frostbite. In th e case of dermal exposure, the SDS for R

- 513A recommends that person(s) immediately wash the affected area with water and remove all contaminated clothing; if frostbite occurs, bathe (not rub) the affected area with lukewarm, not hot, water. If water is not available, cover the affected area with a clean, soft cloth, and seek medical attention immediately. Exposures of R

- 513A to the eyes could cause eye irritation. I n case of ocular exposure, the SDS for R

- 513A recommends that person(s) immediately flush the eyes, including under the eyelids, with copious amounts of water for 15 minutes. EPA’s review of the human health impacts of this proposed substitute is contained in the public docket for this decision. These risks and procedures after exposure are simil ar for other common refrigerants. TheFinal

— July 2, 2015

6 potential health effects of R

- 513A can be minimized by following the exposure guidelines , and ventilation and PPE r ecommendations outlined in the SDS for R

- 513A and this risk screen.


### 6

. FLAMMABILITY ASSESSMENT
R

- 513A is classified as an A1 refrigerant by ASHRAE, and is considered to be nonflammable (DuPont Fluoroproducts 2014 ; ASHRAE 2015 ). Based on this classification, manufacture, servicing, and use of R

513A is not expected to present a flammability risk in cold sto rage warehouses or industrial process refrigeration

. 

### 7

. ASPHYXIATION ASSESSMENT
R

- 513A is not expected to cause a significant risk of asphyxiation when used in cold storage warehouses or industrial process refrigeration

. These systems are typically install ed in large spaces (e.g., outdoors, on roofs, large manufacturing facilities) where it would be unlikely for a release of R

- 513A to reduce the normal concentration of oxygen in air (21 percent) in the space to 12 percent, 5 even in the case of a catastrophi c leak. EPA believe s that by installing R

- 513A cold storage warehouses and industrial process refrigeration systems in appropriate spaces according to guidelines from the manufacturer and the SDS for R

- 513A , potential releases of R

- 513A are not expected to pose a significant risk of asphyxiation or impaired coordination to personnel , and are consistent with the potential risks for other commonly used refrigerants in these end uses

. 

### 8

. OCCUPATIONAL EXPOSURE ASSESSMENT
To ensure that use of t he proposed substitute in cold storage warehouses and industrial process refrigeration does not pose an unacceptable risk to workers during installation, servicing, and disposal, occupational exposure modeling at installation was performed for the proposed substitute. All installation, maintenance, and disposal activities for R

- 513 A cold storage and industrial refrigeration systems are anticipated to occur on

- site. Although modeling is only performed for installation, it is assumed that exposure during serv icing and disposal would not exceed exposure during installation because similar refrigerant charging and/or recovery equipment , as well as the connection of pipes to transfer the refrigerant , would be used. Furthermore, because it is likely that essential ly equivalent or marginally less refrigerant amount remains in the unit at disposal as would be present during installation or servicing , it is assumed that installation of refrigeration units in cold storage warehouses or industrial process refrigeration systems wo uld require transfer of a greater amount of refrigerant, and thus result in greater worker exposure. Thus, occupational exposure was conservatively modeled based on installation.

The submitter anticipates that R

- 513A in cold storage warehouse refrigeration will have a typical charge size of 50 kg and a maximum charge size of 2,000 k g. However, charge sizes in cold storage warehouses can vary greatly by the storage volume, the desired temperature for refrigeration, and refrigeration feed (i.e. , direct expansion, flooded, or liquid recirculation)

. According to the submitter, charge sizes in i ndustrial process refrigeration system s can range from a typical charge size of 5 0 kg to a maximum charge size of 5 ,000 kg. The anticipated maximum and typica l charge sizes for the proposed applications are summarized in Table 5.

Table 5. Typical and Maximum Charge Sizes for R

- 513A Cold Storage Warehouses and Industrial Process Refrigeration Applications
End

- Use Typical Charge Size (kg) Maximum Charge Size (kg) Cold Storage Warehouses 50 2,000

5 Twelve percent oxygen in air is the No Observed Adverse Effect Level (NOAEL) for hypoxia (ICF 1997).Final

— July 2, 2015

7 Industrial Process Refrigeration 50 5,000

Installation of cold storage warehouses and industrial process refrigeration systems is expected to occur with limited frequency (up to approximately one event per day) and with limited duration of exposure to the refrigerant charge. Release points during charging would be connection/disconnection of temporary lines from charging equipment. Refrigerant contained in temporary lines during charging would be recovered, and breaking of fittings should result in de minimus releases . Such activities and related exposure is anticipated to occur within 15

- 30 minutes (per event/day). To eva luate the risk of exposure at installation, the maximum modeled exposur e concentration for each component of R

- 513A was compared to the 15

- min ute STEL values , which were developed by EPA for each component based on the individual WEEL value s

. The methodology used for this screening assessment is described in Chapter 5 of the Background Document. A box

- model approach was used to evaluate potential worker exposure to alternative refrigerants. This approach has been widely used for many years to e stimate probable exposures of workers to hazardous airborne materials, and has been described in detail by NIOSH. This model takes into consideration the duration and magnitude of the resulting exposure which is influenced by 1) duration and intensity of t he release, 2) rate at which contaminated air is diluted with uncontaminated air, 3) proximity of the worker to the source of the release, and 4) the length of time the worker remains in the affected space. The release per event was assumed to be 1 perce nt of the equipment charge during installation 6 and was multiplied by the number of installations est imated to occur over a workday (i.e

. , one installation was assumed for both cold storage and industrial process refrigeration systems )

. The analysis models the typical and maximum anticipated charge sizes for cold storage warehouse and industrial process refrigeration systems, due to the wide range in charge sizes provided by the submitter. Because cold storage warehouses and industrial p rocess refrigeration systems have the same typical charge size and are anticipated to result in similar exposures at installation, Table 6 only presents the typical charge size of 50 kg once

. The maximum 15

- minute TWA exposures for each R

- 513A constituent were estimated for the servicing exposure scenario and compared to their respective STELs (see Table 6 )

. Because HFO

- 1234yf is present in larger concentrations and because it has a lower expos ure limit than HFC

- 134a, Table 6 only presents exposures for HFO

- 1234yf, the component with greater potential concerns.

Table 6. Occupational Risk Assessment at Installation for R

- 513A a

6 IPCC (2006) estimate s that first

- fill losses during installation of industrial refrigeration systems in food processing and cold storage warehouse systems can range from 0.5% to 3% ; DECC (2011) estimates that first

- fill losses for cold storage and industrial process refrigeration is approximately 1%; and SKM Enviros (2011) suggests that this loss rate should be l ess than 4%. A proposed update to EPA’s Vintaging Model recommends a first

- fill emissions rate of 1% from cold storage and industrial process refrigeration manufactured after 1990.Final

— July 2, 2015

8 System Scenario Charge Size (kg) R

- 513A Component 15

- minute TWA Occupational

Exposure

(ppm) 1 5

- min Short Term Exposure

Limit (ppm) b Acute Toxicity Exposure Limit (ppm) c Cold Storage Warehouse or Industrial Process

Refrigeration Typical Charge Size 50 HFO

- 1234yf 70

1,500 101,000 Cold Storage Warehouse Maximum Charge Size 2,000 HFO

- 1234yf 2,700
Industrial Process

Refrigeration Maximum Charge Size 5,000 HFO

- 1234yf 6,700
Bold font indicates modeling results.

a Cells highlighted in green are the scenarios that are deemed to be acceptable given various modeling assumption options. b EPA

- derived STEL; see Table 3 for more information.

c ATEL for HFO

- 1234yf is 101,000 ppm; see Table 3 for more information.
Based on the assumptions described above, the s hort

- term (15

- minute) worker exposure concentrations are not likely to exceed the STEL for the HFO

- 1234yf component of R

- 513A for the typical charge size for cold storage warehouses and industrial process refrigeration . The modeling indicates that worker exposure could exceed the STEL for the HFO

- 1234yf component for the installation sc enario for the maximum charge size for cold storage warehouses and industrial process refrigeration ; however, t he estimated exposures were derived using conservative assumptions and do not take into account the use of ventilation or PPE. In addition, all of the estimated exposures are significantly lower than the ATEL for HFO

- 1234yf which is a limit intended to reduce the risks of acute toxicity hazards in normally occupied, enclosed spaces according to ASHRAE Standard 34

. T he maximum charge sizes for both end

- uses are representative of l arge system s , and as such, additional precautions are appropriate for cold storage warehouses and industrial process refrigeration applications. Furthermore, the modeling assumptions do not reflect the use of any local exhaust ventilation or other engineering controls, which are likely to be used during installation, servicing, and disposal operations, thereby preventing significant exposure to R

- 513A

. Cold storage warehouses and i ndustrial process refrigeration systems are complex systems used in various types of commercial and manufacturing industries and are installed in large facilities. Such facilities are already equipped with proper engineering controls and industrial hygiene practices for safety purposes and ther efore are expected to have the capabilities to mitigate exposures to any large releases of refrigerant from the refrigeration system. Facility personnel are also equipped with proper PPE and trained to work in such environments that contain numerous workpl ace hazards, and are expected to be only at marginally incremental risk for exposures to refrigerant releases in these settings. Furthermore , these types of systems are typically installed, maintained, and disposed by trained and EPA Section 608

- certified refrigerant technicians using proper industrial hygiene techniques. When installing, servicing, or disposing of such large refrigeration systems , these techniqu es should be strictly followed. Adherence to the proposed substitute’s SDS and use of proper eng ineering controls and PPE make it unlikely that exposure to R

- 513A would occur

. Adequate ventilation should always be established during any use, handling, or storage of R

- 513A

. If installation, recovery, and/or disposal is taking place in an enclosed spac e without any mechanical ventilation, facilities should be cleared of non

- essential personnel and technicians should wear a self

- contained breathing apparatus (SCBA) and other appropriate protective equipment. Engineering controls should include vapor

- in a ir detection systems and local exhaust ventilation during use of R

- 513A to prevent dispersion throughout the workplace. In addition, an eye wash and safety shower should be near the manufacturing facility and locations where R

- 513A is stored and ready for use. In general, use of PPE is recommended, such as splash goggles, mechanically

- resistanceFinal

— July 2, 2015

9 gloves when handling cylinders , and chemically

- resistant gloves when handling the gas mixture (e.g., butyl rubber, chlorinated polyethylene, or neoprene). Toxicity risks would be further minimized by t he installation of signage , which warns room occupants to remain standing (as higher concentrations are likely to accumulate near the floor) , not enter recessed parts of the facility (e.g. , maintenance crawl spaces and below grade service areas) , and exit the facility immediately should they hear the refrigerant detector alarm and/or smell the leaked refrigerant

. In addition, as for other halogenated refrigerants, there is a risk of generation of toxic degradation products such as hydrogen fluoride and hydrogen chloride if the components of R

- 513A (i.e., HFC

- 134a and HFO

1234yf ) are exposed to high temperatures or fire. Other reaction products such as carbon dioxide might also be present. Containers should be stored in cool, dry conditions (maximum storage temperature should be 40 ° C) in well

- sealed receptacles and should not be allowed to contact open flames, glowin g metal surfaces, or electrical heating elements. EPA believes that when proper handling and disposal guidelines are followed , in accordance with both good industrial hygiene practices and the SDS for R

- 513A and its components, there is no significant risk to workers during the use of R

- 513A in cold storage warehouses and industrial process refrigeration end

- uses

. 

### 9

. GENERAL POPULATION EXPOSURE ASSESSMENT
R

- 513A is not expected to cause a significant risk to human health in the general population when manuf actured for use and used as a refrigerant in cold storage warehouses and industrial process refrigeration systems . The proposed substitute will be manufactured in a closed process and is proposed for use in closed systems; thus, significant releases are no t anticipated. At room temperature, R

- 513A is a gas and, therefore, releases to ground or surface water are not anticipated, as R

- 513A is anticipated to dissipate into the atmosphere upon release to outside air (i.e., because natural ventilation rates woul d be higher and there is no enclosed space to maintain a high concentration of R

- 513A ). Should air releases during manufacturing operations occur, engineering controls should be used (e.g., carbon absorption scrubbers) to collect R

- 513A and prevent the rel ease of R

- 513A to the atmosphere. EPA believes that by using proper engineering controls and by following disposal and containment recommendations outline d in the proposed substitute’s SDS and this risk screen , exposure to R

- 513A is not expected to pose a significant toxicity risk to the general population.Final

— July 2, 2015

10 

### 10

. REFERENCES
ACGIH. 2012. Guide to Occupational Exposure Values. American Conference of Governmental Industrial Hygienists.
AIHA. 2013. WEEL® Values (2011). 2013 ERPG/WEEL Handbook. AIHA Guideline Foundation. Available online at: https://www.aiha.org/get

involved/AIHAGuidelineFoundation/WEELs/Pages/default.aspx

. ANSI/ASHRAE. 2015. 2015 Supplement to Standard 34: Designation and Safety Classification of Refrigerants. American Society of Heating, Refrigerating and Air

- Conditioning En gineers, Inc. ANSI/ASHRAE. 2013. Standard 62: Ventilation for Acceptable Indoor Air Quality. American Society of Heating, Refrigerating and A ir

- Conditioning Engineers, Inc. ANSI/ASHRAE. 2010a. Standard 15: Safety Standard for Refrigeration Systems. America n Society of Heating, Refrigerating and Air

- Conditioning Engineers, Inc. ANSI/ASHRAE. 2010b. Standard 34: Designation and Safety Classification of Refrigerants. American Society of Heating, Refrigerating and Air

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