FINAL—October 10, 2014

Significant New Alternatives Policy Program

Foam-Blowing Sector

Risk Screen on Substitutes in Flexible Polyurethane Foams

Substitute: trans-1-Chloro-3,3,3-trifluoroprop-1-ene

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. 

The 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. The

EPA has already screened a large number of substitutes in many end uses 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 the EPA's docket.

The purpose of this risk screen is to supplement the EPA’s Background Document on the foam blowing 

sector (EPA 1994) (hereinafter referred to as the Background Document). This risk screen evaluates the 

potential use of trans-1-chloro-3,3,3-trifluoroprop-1-ene (hereinafter referred to as SolsticeTM 1233zd(E))

as a blowing agent substitute in flexible polyurethane foam. SolsticeTM 1233zd(E)) presently has EPA 

SNAP approval for use as a blowing agent in rigid polyurethane and polyisocyanurate laminated 

boardstock; rigid polyurethane appliance, commercial refrigeration, spray, and slabstock; and integral skin 

polyurethane foams. Table 1 presents information on the proposed substitute. 

Table 1. Composition of SolsticeTM 1233zd(E)

Constituent Chemical Formula CAS Number Percent of Total

(by weight)

trans-1-Chloro-3,3,3-trifluoroprop-1-ene C3H2ClF3 102687-65-0 >99%

Potential Impurities (maximum concentration)
FINAL—October 10, 2014

The potential risks associated with use of foam blowing agents have been examined at length in the 

Background Document. The reader is referred to this reference for a detailed discussion of the 

methodologies used to conduct this risk screen. This risk screen addresses flammability risk and assesses 

the impact of potential releases of SolsticeTM 1233zd(E) on the atmosphere and climate. Occupational 

exposure was assessed to ensure that manufacture and application of the proposed substitute in the 

proposed foam-blowing end use does not pose unacceptable risk to workers. Lastly, general population

exposure was assessed to ensure that the proposed substitute would not pose an unacceptable risk to the 

population at large. 

Section 2 of this report summarizes the results of the risk screen for the proposed substitute. The 

remainder of the report is organized into the following sections:

 Section 3: Atmospheric Assessment 

 Section 4: Volatile Organic Compound Assessment 

 Section 5: Flammability Assessment

 Section 6: Potential Health Effects

 Section 7: Occupational Exposure Assessment

 Section 8: General Population Assessment

 Section 9: References

2. SUMMARY OF RESULTS

SolsticeTM 1233zd(E) is recommended for SNAP approval as a foam-blowing agent in flexible 

polyurethane. The EPA's risk screen indicates that the use of the proposed substitute will be less harmful to 

the atmosphere than the continued use of CFC-11, CFC-113, HCFC-141b, and HCFC-22, as well as other 

commonly used blowing agents. In addition, SolsticeTM 1233zd(E) contributions to volatile organic 

compound (VOC) emissions are not a concern as SolsticeTM 1233zd(E) is exempt under CAA regulations 

(40 CFR § 51.100(s)). Given that appropriate personal protective equipment (PPE) and engineering 

controls (e.g., exhaust ventilation, vapor-in-air detection systems) will be used during installation, 

maintenance, and disposal activities, no significant toxicity risks to workers or the general population are 

expected. In addition, based on the characteristics of the proposed substitute and the proper precautions 

listed in the MSDS for SolsticeTM 1233zd(E), the proposed substitute is not expected to present a 

significant flammability concern during manufacture or end use (see Section 7). 

3. ATMOSPHERIC ASSESSMENT

This section presents an assessment of the potential risks to atmospheric integrity posed by the use of 
FINAL—October 10, 2014

SolsticeTM 1233zd(E) in the foam blowing sector. The ozone depletion potential (ODP), global warming 

potential (GWP), and atmospheric lifetime (ALT) of the proposed substitute are presented in Table 2. As 

compared with ODS blowing agents currently in this end use such as CFC-11, CFC-113, HCFC-141b, and

HCFC-22, SolsticeTM 1233zd(E) is substantially less harmful to the ozone layer, has less climate impact, 

and a shorter atmospheric lifetime. In addition, SolsticeTM 1233zd(E) also has lower climate impact and a 

shorter atmospheric lifetime than those predicted for other substitutes examined in the Background 

Document, as well as commonly used blowing agent HFC-134a. SolsticeTM 1233zd(E) has a non-zero 

ODP, but, at 0.00024, this value is very small when compared with continued used of HCFC-141b or 

HCFC-22. A recent report by Wang et al. (2011) modeled the potential of SolsticeTM 1233zd(E) to affect 

the amount of ozone in the global atmosphere (tropospheric and stratospheric). This report found that the 

release of all SolsticeTM 1233zd(E), assuming it were substituted for all compounds it might replace and 

that the entire amount used were released, would have statistically zero impact on global atmospheric 

ozone (less than 0.01% change in total column ozone). Thus, EPA believes that use of SolsticeTM 

1233zd(E) would result in substantially less harm to the climate and ozone layer than the continued use of

ODS and other commonly used blowing agents.

Table 2. Atmospheric Impacts of SolsticeTM 1233zd(E) Compared with CFC-11, CFC-113, HCFC141b, HCFC-22, and HFC-134a

Chemical ODP GWP (100-year) ALT

SolsticeTM 1233zd(E) 0.00024

a 1b 26.0 daysb

CFC-11 1.0c 4,750d 45 yearsd

CFC-113 0.85c 6,130d 85 yearsd

HCFC-141b 0.12c 725d 9.3 yearsd

HCFC-22 0.13c 1,810d 12 yearsd

HFC-134a 0 1,430d 12 yearsd

a Assuming SolsticeTM 1233zd(E) emissions occur with the same geographic distribution as the blowing agents it might replace (Wang et al. 2011).

b Hodnebrog, O. et al. (2013)

cWMO (2011)

d

IPCC 4th Assessment Report (Forster et al. 2007)

4. VOLATILE ORGANIC COMPOUND ASSESSMENT

SolsticeTM 1233zd(E) is exempt from the definition of volatile organic compound (VOC) under CAA 

regulations (40 CFR § 51.100(s)). Therefore, environmental impacts from the release of SolsticeTM 

1233zd(E) as a VOC are not a concern. 

5. FLAMMABILITY ASSESSMENT

SolsticeTM 1233zd(E) is not considered to be flammable at ambient temperatures and atmospheric pressure, 

but it can ignite when mixed with air under pressure and exposed to strong ignition sources; also, 

containers of SolsticeTM 1233zd(E) may rupture when exposed to heat or temperatures above the proposed 

substitute’s auto-ignition temperature of 380°C (Honeywell 2011a). SolsticeTM 1233zd(E) is not expected 

be used under pressure in flexible polyurethane foam. By keeping SolsticeTM 1233zd(E) away from all 

sources of ignition and high heat and adhering to the other precautions listed in the proposed substitute’s 

MSDS, SolsticeTM 1233zd(E) does not pose a significant flammability risk.

In addition, SolsticeTM 1233zd(E) is expected to be incorporated into a typical flexible polyurethane foam 

formulation (e.g., polyol blend or “B” component) consisting of up to 15% flame retardants and other 

materials (e.g., a co-blowing agent such as CO2) such that the concentration of SolsticeTM 1233zd(E) is 

expected to be less than 5% of the foam formulation by weight, further reducing flammability risk

(Honeywell 2011b, Honeywell 2014). By following the proper precautions specified by the proposed 

substitute’s MSDS, it is unlikely that SolsticeTM 1233zd(E) will pose a significant flammability risk.
FINAL—October 10, 2014

6. POTENTIAL HEALTH EFFECTS

To assess potential health risks from exposure to this proposed substitute, the submitter provided a

workplace environmental exposure limit (WEEL) of 800 ppmfor SolsticeTM 1233zd(E) (OARS 2013). The 

WEEL represents the maximum 8-hour time weighted average (TWA) at which a worker can be exposed

regularly without adverse effects. 

According to the MSDS, exposure to SolsticeTM 1233zd(E) through ocular or dermal absorption, 

inhalation, or ingestion may be harmful. Ocular exposures to SolsticeTM 1233zd(E) will cause serious eye 

irritation and may cause frostbite through dermal exposure. In case of ocular exposure, the MSDS for 

SolsticeTM 1233zd(E) recommends that person(s) should immediately flush the eyes, including under the 

eyelids, with water for 15 minutes; should frostbite occur, affected areas should be rinsed with lukewarm

water. Medical attention should be sought if irritation develops or persists. 

In the case of dermal exposure to SolsticeTM 1233zd(E), the MSDS for SolsticeTM 1233zd(E) recommends 

that person(s) should immediately wash the affected area with water and remove all contaminated clothing

to avoid irritation; should frostbite occur, bathe (do not rub) the affected area with lukewarm, not hot, 

water. If water is not available, cover the affected area with a clean, soft cloth. Medical attention should be 

sought if irritation develops or persists. SolsticeTM 1233zd(E) vapors are heavier than air and cause 

suffocation by reducing oxygen available for breathing, causing asphyxiation in high concentrations. If 

person(s) are exposed to high concentrations, the person(s) will likely not realize that he/she is suffocating, 

but may experience central nervous system effects, such as drowsiness and dizziness. If SolsticeTM 

1233zd(E) is inhaled, person(s) should be immediately removed and exposed to fresh air. The MSDS 

recommends that if breathing is difficult, person(s) should be given oxygen, provided a qualified operator 

is present, and medical attention be sought. SolsticeTM 1233zd(E) is not likely to be hazardous by 

ingestion; however, in case of ingestion, the MSDS recommends the person(s) drink a cup of water, if fully 

conscious, and consult a physician immediately. Do not induce vomiting without medical advice. The 

EPA’s review of the human health impacts of this proposed substitute is contained in the public docket for 

this decision. 

The potential health effects of SolsticeTM 1233zd(E) are unlikely to occur when following good industrial 

hygiene practices and the PPE and engineering control (e.g., ventilation) recommendations outlined in the 

MSDS for SolsticeTM 1233zd(E) and Sections 7 and 8 of this risk screen.

7. OCCUPATIONAL EXPOSURE ASSESSMENT

This section discusses potential occupational exposures to SolsticeTM 1233zd(E) in the manufacture of 

flexible polyurethane foam. Flexible polyurethane foam is estimated to have 100% first year losses, and

the majority of losses are anticipated to occur after manufacture, during processing (Jeffs 2012). For 

flexible polyurethane foams, this would include removing the foam from its molds. However, the resulting 

occupational exposure during this activity is not anticipated to present a significant concern (Jeffs 2012).

Although exposure data were not available for the manufacture of flexible polyurethane foam, 

instantaneous exposure concentrations were modeled for spray foam applications, which have the highest 

exposure potential of all foam types. Using HFC-245fa surrogate data provided by the submitter, the 

maximum modeled exposure for employees involved in the use of SolsticeTM 1233zd(E) for spray foams 

was 291 ppm, which is less than the 8-hour WEEL for SolsticeTM 1233zd(E) (i.e., 800 ppm) (Honeywell 

2011a). Furthermore, given that 291 ppm was calculated from the maximum exposure concentration and 

that exposure concentrations over the time duration were significantly lower than the maximum recorded 

value, concentrations of SolsticeTM 1233zd(E) also would not reach or exceed the WEEL over an 8-hour 

time-weighted average. Because spray foam applications have the highest exposure potential of all foam 
FINAL—October 10, 2014

types, it is unlikely that the time-weighted concentrations during manufacture and processing of flexible

polyurethane foam would result in concentrations higher than those modeled for spray foam applications. 

Therefore, it is unlikely that the acceptable occupational exposure limit for SolsticeTM 1233zd(E) would be 

exceeded during the manufacture and processing of flexible polyurethane foam. 

Although anticipated occupational exposures are well below the exposure limit for SolsticeTM 1233zd(E), 

engineering controls should be in place during manufacture and use of SolsticeTM 1233zd(E), such as 

vapor-in-air detection systems. Adequate ventilation should always be established during any use, 

handling, or storage of SolsticeTM 1233zd(E). In addition, an eye wash and safety shower should be near 

the manufacturing facility and ready for use. In general, use of PPE is recommended, such as respiratory 

protection (a NIOSH-approved positive-pressure supplied-air respirator is recommended where there is 

insufficient ventilation; self-contained breathing apparatuses should be used for rescue and maintenance 

work in storage tanks), chemical splash goggles or face shield, impervious gloves, and chemical-resistant 

boots and clothing (Honeywell 2011a, OSHA 1994). Contaminated clothing is not to leave the workplace 

and must be cleaned before reuse (Honeywell 2011a).

During handling of liquid SolsticeTM 1233zd(E) blowing agent for manufacture of flexible polyurethane

foam, there is also a risk of generation of toxic decomposition products such as hydrochloric acid, 

hydrofluoric acid, and carbonyl halides if liquid SolsticeTM 1233zd(E) is exposed to fires or temperatures 

greater than 250°C. Containers of SolsticeTM 1233zd(E) should not be allowed to contact open flames, 

glowing metal surfaces, or electrical heating elements.

The EPA believes that if proper handling guidelines are followed in accordance with good industrial 

hygiene and manufacturing practices and the MSDS for SolsticeTM 1233zd(E), as described above, 

manufacture of SolsticeTM 1233zd(E) foam does not present a significant risk to workers.

8. GENERAL POPULATION EXPOSURE ASSESSMENT

SolsticeTM 1233zd(E) is not expected to cause a significant impact on human health in the general 

population when manufactured or used for the flexible polyurethane foam end use. Because flexible 

polyurethane foams are estimated to lose 100% of the foam blowing agent during manufacturing and 

processing, the EPA does not anticipate chronic general population exposures to SolsticeTM 1233zd(E)

during the lifetime of the foam. Should releases during manufacturing operations occur, engineering 

controls should be used (e.g., carbon absorption scrubbers) to collect and prevent the release of the 

proposed substitute to the atmosphere. Furthermore, at room temperature and atmospheric pressure, 

SolsticeTM 1233zd(E) is a gas. Therefore, releases to ground or surface water are not anticipated, as 

SolsticeTM 1233zd(E) is anticipated to dissipate into the atmosphere upon release to outside air.

Due to the low toxicity of SolsticeTM 1233zd(E) and its minimal expected release, the EPA believes that 

such exposures do not pose a significant toxicity risk, and SolsticeTM 1233zd(E) is not expected to cause a 

significant impact on human health in the general population when used as a foam blowing agent in 

flexible polyurethane foams.
FINAL—October 10, 2014

9. REFERENCES

Forster, P., V. Ramaswamy, P. Artaxo, T. Berntsen, R. Betts, D.W. Fahey, J. Haywood, J. Lean, D.C. 

Lowe, G. Myhre, J. Nganga, R. Prinn, G. Raga, M. Schulz and R. Van Dorland. 2007. Changes in 

Atmospheric Constituents and in Radiative Forcing. In: Climate Change 2007:The Physical Science 

Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel 

on Climate Change [Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M.Tignor and 

H.L. Miller (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA.

Hodnebrog, Ø., Etminan, M., Fuglestvedt, J. S., Marston, G., Myhre, G., Nielsen, C. J., Shine, K. P., 

Wallington, T. J.: Global Warming Potentials and Radiative Efficiencies of Halocarbons and Related 

Compounds: A Comprehensive Review, Reviews of Geophysics, 51, 300-378, doi:10.1002/rog.20013, 

2013.

Honeywell, Inc. 2011a. SNAP Submission to EPA for SolsticeTM 1233zd(E). May 13, 2011. 

Honeywell, Inc. 2011b. Response to Incomplete SNAP Submission for SolsticeTM 1233zd(E). October 20, 

2011.

Honeywell, Inc. 2012a. SolsticeTM 1233zd(E) Material Safety Data Sheet. February 28, 2012.

Honeywell, Inc. 2012b. Response to A Few More Questions on Foam Uses for SolsticeTM 1233zd(E). 

February 6, 2012.

Honeywell, Inc. 2012c. Response to Incomplete SNAP Submission for SolsticeTM 1233zd(E). January 31, 

2012. 

Honeywell, Inc. 2014. Addendum to SNAP Submission to EPA for SolsticeTM 1233zd(E). March 4, 2014.

Jeffs, Mike. 2012. Personal communication between ICF International and Mike Jeffs. April 24–26, 2012. 

Occupational Alliance for Risk Science (OARS). 2013. Workplace Environmental Exposure Level 

(WEEL): trans-1-Chloro-3,3,3-Trifluoropropene (1233zd(E)). Conducted for Honeywell International, 

2013. 

OSHA. 1994. General description and discussion of the levels of protection and protective gear. 1910.120 

App B. Last updated August 22, 1994. Available at: 

http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=9767

U.S. EPA. 1994. Significant New Alternatives Policy Technical Background Document: Risk Screen on 

the Use of Substitutes for Class I Ozone-depleting Substances: Refrigeration and Air Conditioning. 

Stratospheric Protection Division. March, 1994.

U.S EPA. 2011. National Emissions Inventory Air Pollutant Emissions Trends Data. Accessed 23 

December 2011. Updated October 2011. Available at: 

http://www.epa.gov/ttn/chief/trends/index.html#tables

U.S. EPA. 2012. Risk Screen on the Use of SolsticeTM 1233zd(E) in Rigid Polyurethane and 

Polyisocyanurate Laminated Boardstock; Rigid Polyurethane Appliance, Commercial Refrigeration, 

Spray, and Slabstock; Integral Skin Polyurethane. Stratospheric Protection Division. August 2012. 
FINAL—October 10, 2014

Wang D., Olsen S., Wuebbles D. Undated. “Three-Dimensional Model Evaluation of the Global 

Warming Potentials for tCFP.” Department of Atmospheric Sciences. University of Illinois, Urbana, IL. 

Draft Report. 

Wang D., Olsen S., Wuebbles D. 2011. “Preliminary Report: Analyses of tCFP’s Potential Impact on 

Atmospheric Ozone.” Department of Atmospheric Sciences. University of Illinois, Urbana, IL. September 

26, 2011. 

WMO (World Meteorological Organization). 2011. Scientific Assessment of Ozone Depletion: 2010, 

Global Ozone Research and Monitoring Project—Report No. 52, 516 pp., Geneva, Switzerland, 2011.