Final—July 2, 2015

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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 Significant 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 ODSusing 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 potential use of R-513A (also known as Opteon® XP10) as a substitute in the cold storage 

warehouses and industrial process refrigeration end-uses. Table 1 presents the composition of the proposed 

substitute. 

Table 1. Composition of R-513A and Potential Impurities

Constituent Chemical Formula CAS Number Concentration

(Weight Percent)

2,3,3,3-Tetrafluoropropene 

(HFO-1234yf) CH2CFCF3 754-12-1 ≤56%

1,1,1,2-Tetrafluoroethane

(HFC-134a) CF3CH2F 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 Assessment

• Section 8: Occupational Exposure Assessment 
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• 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 atmospheric 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 industrial 

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 enduse, 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. 

In addition, potential health risks from exposure to the proposed substitute is considered to be a larger 

concern for workers than asphyxiation,1 due to the large spaces in which these systems are installed and 

serviced. Therefore, an asphyxiation 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) Standards 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 R513A in cold storage warehouses and industrial process refrigeration. The ozone depletion potential 

(ODP), global warming potential (GWP), and atmospheric lifetime (ALT) of the proposed substitute are 

presented in Table 2.

The proposed substitute is 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 Standard 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 Refrigerants ASHRAE Standard 34 establishes a uniform system for assigning reference 

numbers, safety classifications, and refrigerant concentration limits to refrigerants. Safety classifications based 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

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well as commonly utilized refrigerants HFC-134a, R-404A, and R-507A. Thus, EPA believes that the use 

of R-513A would result in substantially less harm to the climate and ozone 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 NAc

Individual Components

HFC-134a 0 1,430 14

HFO-1234yf 0 4d 11 daysd

CFC-12 0.82 10,900 100

HCFC-22 0.13 1,810 12a

HFC-134a 0 1,430 14

R-404Ae 0 3,922 NAf

R-507Ag 0 3,985 NAh

a WMO 2010 Scientific Assessment Report (2011)

b IPCC 4th 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 the ALT for HFC-134a is 14 years (IPCC 4th 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-125 is 29 years and 

ALT for HFC-143a is 52 years (IPCC 4th 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 toxicity threshold values for comparison to 

modeled exposure concentrations for different scenarios. According to ASHRAE Standard 34-2013, R513A is listed under safety group A1 with a RCL of 72,000 ppm (ASHRAE 2015). ASHRAE 34 RCLs are 

intended to reduce the risks 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 proposed RCL for R-513A to ensure that significant end-use 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 occupational 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 exposure concentrations to emergency guidance levels (EGL). In the absence of 
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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 exposures were evaluated 

on a component basis (i.e., HFC-134a and HFO-1234yf). Table 3 lists the relevant toxicity limits for R513A and its components, and is followed by Table 4, which provides an explanation of each toxicity 

limit. EPA’s approach for identifying 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 101,000c

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 1,960 ppm was developed by EPA based on the 

653 ppm acceptable exposure 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 method 

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 101,000 ppm (DuPont Fluoroproducts 

2014).

Table 4. Explanation of Exposure Limit-Related Terminologya

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). Determination 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 the refrigerant concentration limit intended to reduce 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 impairing 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 

exceeded during a workday, even if the 8-hour TWA is within the 

threshold limit value-time weighted average (TLV–TWA), set by ACGIH. 
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AEGLb,c

Acute Exposure Guideline 

Level 1

AEGL-1 is the airborne concentration (expressed as ppm or mg/m3) 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/m3) of a 

substance above which it is predicted that the general population, 

including susceptible individuals, could 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/m3) 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 –TimeWeighted AverageThe 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 Applicable 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-513A can cause 

symptoms of asphyxiation when present in concentrations high enough to significantly lower oxygen 

concentrations below 19.5 percent by volume, such as headaches, ringing in ears, dizziness, drowsiness, 

nausea, vomiting, depression of all senses, and also unconsciousness. Under some circumstances of overexposure (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. Furthermore, 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 accordance 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 the 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. In 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 similar for other common refrigerants. The 
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potential health effects of R-513A can be minimized by following the exposure guidelines, and ventilation 

and PPE recommendations 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 R513A is not expected to present a flammability risk in cold storage 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 installed 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 

catastrophic leak. EPA believes 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 the 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-513A 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 servicing 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 essentially 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 would 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 kg. 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 

industrial process refrigeration systems can range from a typical charge size of 50 kg to a maximum charge 

size of 5,000 kg. The anticipated maximum and typical 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

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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 evaluate the risk of exposure at 

installation, the maximum modeled exposure concentration for each component of R-513A was compared 

to the 15-minute STEL values, which were developed by EPA for each component based on the individual 

WEEL values.

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 estimate 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 the 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 percent of the equipment charge during installation6 and was 

multiplied by the number of installations estimated 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 process 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 exposure 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-513Aa

 6 IPCC (2006) estimates 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 less 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

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System Scenario Charge 

Size (kg)

R-513A 

Component

15-minute TWA 

Occupational 

Exposure 

(ppm)

15-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 short-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 scenario for the maximum 

charge size for cold storage warehouses and industrial process refrigeration; however, the 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. 

The maximum charge sizes for both end-uses are representative of large systems, 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 industrial 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 therefore 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 workplace 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 techniques should be strictly followed.

Adherence to the proposed substitute’s SDS and use of proper engineering 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 space 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 air 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-resistance 
Final—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 the 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 HFO1234yf) 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, glowing 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 

manufactured 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 not 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 would 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 release of R-513A to the atmosphere. EPA believes that by using proper 

engineering controls and by following disposal and containment recommendations outlined 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/getinvolved/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 Engineers, Inc.

ANSI/ASHRAE. 2013. Standard 62: Ventilation for Acceptable Indoor Air Quality. American Society of 

Heating, Refrigerating and Air-Conditioning Engineers, Inc.

ANSI/ASHRAE. 2010a. Standard 15: Safety Standard for Refrigeration Systems. American 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-Conditioning Engineers, Inc. DuPont Fluoroproducts. 2014. 

Opteon® XP10 for Use as a Refrigerant. Significant New Alternatives Policy Program Submission to the 

United States Environmental Protection Agency. August 2014.

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