Final—July 2, 2015

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Significant New Alternatives Policy Program

Foam-Blowing Sector

Risk Screen on Substitutes in Rigid Polyurethane Appliance Foam; Rigid Polyurethane 

and Polyisocyanurate Laminated Boardstock; Rigid Polyurethane Spray, Commercial 

Refrigeration, and Sandwich Panels; Rigid Polyurethane Slabstock and Other; Flexible 

Polyurethane; Integral Skin Polyurethane; and Phenolic Insulation Board and Bunstock

Substitute: HFO-1336mzz(Z) (Formacel® 1100)

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-uses within all of the major ODS-using 

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 foam blowing 

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

potential use of HFO-1336mzz(Z) (also known as 2-Butene, 1,1,1,4,4,4-hexafluoro-,(2Z-) and hereinafter 

referred to as Formacel® 1100) as a substitute in Rigid Polyurethane Appliance Foam; Rigid 

Polyurethane and Polyisocyanurate Laminated Boardstock; Rigid Polyurethane Spray, Commercial 

Refrigeration, and Sandwich Panels; Rigid Polyurethane Slabstock and Other; Flexible Polyurethane; 

Integral Skin Polyurethane; and Phenolic Insulation Board and Bunstock. Table 1 presents information on 

the proposed substitute.
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Table 1. Composition of Formacel® 1100

Constituent Chemical Formula CAS Number Percent of Total

(by weight)

2-Butene, 1,1,1,4,4,4-hexafluoro-,(2Z-)

(HFO-1336mzz(Z)) CF3CHCHCF3 692-49-9 >99%

Potential Impurities (maximum concentration)

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 Formacel® 1100 on the atmosphere, climate and other environmental 

impacts. Occupational exposure was modeled to ensure that manufacture and application of the proposed 

substitute in the proposed foam blowing end-uses does not pose unacceptable risk to workers. Lastly, 

general population exposure modeling was performed 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: Potential Health Effects

• Section 6: Flammability Assessment

• Section 7: Occupational Exposure Assessment

• Section 8: General Population Assessment

• Section 9: Aquatic and Ecosystem Impact Assessment

• Section 10: References

2. SUMMARY OF RESULTS

Formacel® 1100 is recommended for SNAP approval as a foam-blowing agent in the following end-uses: 

rigid polyurethane appliance foam; rigid polyurethane and polyisocyanurate laminated boardstock; rigid 

polyurethane spray, commercial refrigeration, and sandwich panels; rigid polyurethane slabstock and 

other; flexible polyurethane; integral skin polyurethane; and phenolic insulation board and bunstock. 
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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 blowing agents. Formacel® 1100 is regulated as 

a volatile organic compound (VOC) under the CAA (40 CFR 51.000) and emissions should be controlled 

through regulations and standard industry practices. In addition, based on the non-flammable nature of the 

proposed substitute, Formacel® 1100 is not expected to present a significant flammability concern during 

manufacture or end-use (see Section 6).

Given that appropriate personal protective equipment (PPE) (e.g., respiratory protection, goggles, 

impervious gloves, chemical-resistant clothing and boots) consistent with Occupational Safety & Health 

Administration (OSHA) guidelines will be used during manufacture; and proper procedures according to 

the manufacturer’s Safety Data Sheet (SDS) (including provisions of engineering controls [e.g., exhaust 

ventilation, vapor-in-air detection systems]) will be used during manufacturing and application activities, 

no significant toxicity risks to workers or the general population are expected. 

3. ATMOSPHERIC ASSESSMENT

This section presents an assessment of the potential risks to atmospheric integrity posed by the use of 

Formacel® 1100 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 to CFC-11 and HCFC-141b, CFC-113, and HCFC-22, Formacel® 1100 is substantially less 

harmful to the ozone layer, has less climate impact, and a shorter ALT. Formacel® 1100 has a non-zero 

GWP, but at 8.9, this value is very small when considering continued use of HCFC-141b or HCFC-22. 

Further, Formacel® 1100 has a lower climate impact and a shorter ALT than those predicted for other 

substitutes examined in the Background Document. Thus, EPA believes that use of Formacel® 1100

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 Formacel® 1100 Compared to Other Foam-Blowing Agents

Refrigerant ODPa GWPb ALT (years)b

Formacel® 1100 0c 8.9c 22 daysc

CFC-11 1.0 4,750 45

CFC-113 0.85 6,130 85

HCFC-141b 0.12 725 9.3

HCFC-22 0.04 1,810 12

HFC-134a 0 1,430 14

HFC-245fa 0 1,030 7.6

HFC-365mfc 0 794 8.6 aWMO (2011)

b IPCC 4th Assessment Report (Forster et al. 2007) c DuPont (2011c)

4. VOLATILE ORGANIC COMPOUND ASSESSMENT

Formacel® 1100 is regulated as a VOC under the CAA (40 CFR 51.000). Through regulations and 

standard industry practices, emissions of Formacel® 1100 should be controlled. The submitter has 

indicated that a petition has been submitted to exempt this compound from the definition of VOC for 

purposes of regulations in state implementation plans for local air quality; however, Formacel® 1100

continues to be regulated as a VOC for that purpose unless and until EPA issues a final rule exempting it.

An assessment was performed to compare the annual VOC emissions from use of Formacel® 1100 in the 

foam blowing end-uses in one year to other anthropogenic sources of VOC emissions. Assuming the 
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submitter’s maximum anticipated annual production of Formacel® 1100 for all proposed foam blowing 

end-uses is entirely released (in the absence of controls), approximately [ ] MT of VOCs would be 

emitted. This is approximately equal to [ ] percent of all anthropogenic VOC emissions from 2013 in the 

United States;

1 however, the release of total production for all foam blowing end-uses is extremely 

unlikely to occur. Thus, an additional analysis was performed to determine likely annual VOC emissions 

from use of Formacel® 1100 in the foam blowing sector. Table 3 summarizes leak estimates and market 

penetrations from the Vintaging Model for the proposed foam blowing end-uses.

Table 3. Foam Release Rates and Market Penetrations by End-Use

Foam End-Use Annual Leak 

Rate First Year Lossa Disposal Loss Lifetime (yrs)

Average Annual 

Release Rateb

Market 

Share

PU Rigid – Commercial 

Refrigeration 0.25% 6.0% 90% 15 6.0% 1%

PU Rigid – Slabstock 0.75% 38% 51% 15 6.0% 1%

PU Rigid – Spray 1.5% 15% 1.0% 56 0.3% 17%

PU Rigid – Appliance 0.25% 3.8% 40% 14 3.0% 11%

PU Rigid – Sandwich 

Panels 0.50% 5.5% 70% 50 2.0% 2%

PU and PIR Rigid –

Boardstock 1.0% 6.0% 44% 50 1.0% 64%

Flexible PU - Slabstock 0.0% 100% 0.0% 1 100% 1%

Flexible PU - Integral 

Skin 2.5% 95% 0.0% 2 49% 0%

Phenolic Insulation 

Board and Bunstock 0.88% 23% 49% 32 2.0% 2%

Source: Vintaging Model (v4.4_10.13.14). a First year losses include losses at manufacture and other production steps that occur prior to end-use. b Calculated as (Leak Rate + First Year Loss + Disposal Loss)/Lifetime

Assuming the average annual release rates for each proposed foam blowing end-use, and that use of 

Formacel® 1100 is distributed according to existing market share for each proposed foam end-use,2

approximately [ ] MT of VOCs would be expected to be released into the atmosphere annually. This 

amount is approximately [ ] percent of all anthropogenic VOC emissions in the United States. In addition, 

the end-uses with the greatest annual release rate (e.g., integral skin and flexible polyurethane slabstock) 

are reasonably expected to occur indoors in a manufacturing or disposal facility, which would have 

engineering controls in place (e.g., carbon adsorption systems or scrubbers) such that actual quantities of 

Formacel® 1100 emissions would be less than the quantity calculated in this assessment.

Although the VOC emissions for these foam blowing applications are several orders of magnitude lower

than other anthropogenic emissions, it is likely that the estimated VOC emissions estimated here can be 

further reduced. Furthermore, there are acceptable foam blowing agents currently in use that are VOCs 

(e.g., hydrocarbons, formic acid), and thus, use of Formacel® 1100 is not expected to increase VOC 

emissions relative to these other acceptable substitutes.

 1 Based on the 2013 annual total VOC emissions for the United States (i.e., approximately 16.1x106 MT) as reported in the 

National Emissions Inventory (EPA 2014).

2 The distribution of proposed foam end-uses is based on EPA’s Vintaging Model and may not necessarily represent the 

submitter’s intended market share for production of Formacel® 1100.
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Therefore, use of Formacel® 1100 would not result in greater impacts on local air quality than other 

available options. In addition, Formacel® 1100 has a lower Maximum Incremental Reactivity (MIR) (i.e., 

0.04) relative to other commonly used blowing agents (i.e., ethane [MIR = 0.28], dichloroethylene [MIR 

= 1.70], and cyclopentane [MIR = 2.39]) (DuPont 2012a). Thus, Formacel® 1100 has a lower potential to 

produce ozone in the atmosphere compared to other commonly used blowing agents. As the calculated 

annual releases of Formacel® 1100 from these analyses are several orders of magnitude smaller than 

other anthropogenic sources of VOC emissions, EPA believes that through the use of regulations and 

standard industry practices, the environmental impacts of these VOCs are not considered a significant 

concern.

5. POTENTIAL HEALTH EFFECTS

To assess potential health risks from exposure to this proposed substitute, DuPont developed a workplace 

environmental exposure level (WEEL) of 500 ppm for Formacel® 1100 (DuPont 2014). 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 SDS, exposure to Formacel® 1100 may be harmful by ocular or dermal absorption, 

inhalation, or ingestion. Regardless of the route of exposure, the SDS recommends that a physician be 

contacted in the case of any exposure. Specifically, in case of ocular exposure, the SDS for Formacel®

1100 recommends that person(s) should immediately flush the eyes with water for at least 15 minutes.

Exposures of Formacel® 1100 to the skin should also immediately be flushed with water for at least 15 

minutes; should frostbite occur, it should be treated by gently warming the affected area. All 

contaminated clothing should be removed and washed before re-use. Inhalation may cause cardiac effects 

such as irregular heartbeat accompanied by atypical chest sensations, heart thumping, apprehension, 

fainting, dizziness, or weakness. In addition, Formacel® 1100 vapors are heavier than air and in high 

concentrations cause suffocation and asphyxiation by reducing oxygen available for breathing. If

Formacel® 1100 is inhaled, person(s) should be immediately moved to fresh air. The SDS further 

recommends that person(s) be kept lying and warm, and provided oxygen and/or artificial respiration if 

necessary. In situations of emergency life support, physicians should use catecholamine drugs with 

particular caution because of possible cardiac rhythm disturbances. In case of ingestion, the SDS 

recommends having the person(s) drink one to two cups of water, if fully conscious. If the person vomits 

while lying on his/her back, the person should be repositioned. Do not induce vomiting without medical 

advice. 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 blowing 

agents.

The potential health effects of Formacel® 1100 are unlikely to occur when following good industrial 

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

SDS for Formacel® 1100 and Sections 7 and 8 of this risk screen. 

6. FLAMMABILITY ASSESSMENT

Formacel® 1100 is not flammable [ ]; thus, the proposed substitute is not considered to pose a 

flammability risk. 

7. OCCUPATIONAL EXPOSURE ASSESSMENT

This section presents an assessment of potential occupational exposures to Formacel® 1100, which is 

anticipated to occur during manufacture of blown foam. Based on this assessment, Formacel® 1100 was

found not to present a significant risk to workers.
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7.1 Occupational Exposure at Manufacture

Limited data are available regarding employee exposures to blowing agents for the proposed foam types

at manufacture. The submitter, however, was able to provide results of a laboratory test to measure the 

worst-case occupational exposures [ ].

Although exposure data were not available for the manufacture of most foam blowing end-uses, such as 

integral skin foam and slabstock foam, which are estimated to have the greatest first year losses (see 

Table 3), the majority of losses are anticipated to occur after manufacture, during processing (Jeffs 2012). 

For slabstock foam and flexible polyurethane foam, this would include cutting of the foam, and for 

integral skin, this would include removing the foam from its molds. However, the resulting occupational 

exposure during these activities is not anticipated to present a significant concern (Jeffs 2012). Further, 

since the monitoring data indicates that the 8-hour time-weighted average exposure concentration ([ ]

ppm) during [ ] foam manufacturing under a conservative scenario are significantly lower than the 8-hour 

WEEL for Formacel® 1100 (500 ppm), it is unlikely that exposure during manufacture and processing of 

the other proposed foam end-uses would result in concentrations beyond the acceptable occupational 

exposure limit.

During manufacture and use of Formacel® 1100, engineering controls should be in place, such as vaporin air detection systems. Adequate ventilation should always be established during any use, handling, or 

storage of Formacel® 1100. 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 NIOSH-approved respiratory 

protection, chemical splash goggles or face shield, impervious gloves, and chemical-resistant boots and 

clothing consistent with OSHA guidelines (DuPont 2011c, OSHA 1994).

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

hygiene and manufacturing practices and the SDS for Formacel® 1100, as described above, manufacture 

of Formacel® 1100 foam does not present a significant risk to workers.

7.2 Occupational Exposure at Spray Foam Application

In addition to occupational exposure during manufacture of blown foam, there is also potential for 

occupational exposure to Formacel® 1100 during rigid polyurethane spray foaming operations, which 

typically occurs on the site of installation, outside of a manufacturing facility. Monitoring data for 

Formacel® 1100 in this application was not available. The submitter did, however, provide the maximum 

occupational exposures recorded during HFC-245fa spray foam application for comparison. The HFC245fa data was used as a surrogate to model exposure concentrations of Formacel® 1100 during spray 

foam application and ensure that it does not present a risk to workers. Due to the lower vapor pressure and 

higher boiling point of Formacel® 1100 (see Table 4), EPA believes that using HFC-245fa as a surrogate 

provides a reasonable estimate of potential air concentrations of Formacel® 1100.

Table 4. Physical Properties of Formacel® 1100 and HFC-245fa Analog

Parameter Formacel® 1100 HFC-245fa Analog

Boiling Point (°F) 92.1 62.4

Vapor Pressure (PSIA at 68°C) 8.7 18

Molecular Weight (g/mol) 164 134

Using the HFC-245fa surrogate data provided, the maximum exposure for employees involved in the use 

of Formacel® 1100 for spray foam was calculated to be [ ] ppm, which is less than the WEEL of 500 

ppm. In addition, the submitter has indicated that Formacel® 1100 will only be used in industrial or 

commercial spray foam applications (DuPont 2012), and thus is anticipated to be used by trained 
Final—July 2, 2015

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personnel where blowing agent losses are minimized and adequate ventilation is in place. As indicated by 

the submitter, the PPE required for spray foam application would typically eliminate the occupational 

exposure or reduce exposure to concentrations below the 500 ppm WEEL (DuPont 2011). EPA believes 

that because proper handling guidelines are followed in accordance with good industrial hygiene and 

manufacturing practices and the SDS for Formacel® 1100, use of Formacel® 1100 for the spray foam 

end-use does not present a significant risk to workers.

8. GENERAL POPULATION EXPOSURE ASSESSMENT

This section screens potential risks to the general population from exposures to releases of Formacel®

1100, specifically acute exposures when used in spray foam, and chronic exposures during the lifetime of 

the foam, because these agents can slowly leak from the foam over time. Because the proper safety 

precautions, as listed in the remainder of this section, are followed, Formacel® 1100 is not expected to 

cause a significant impact on human health in the general population when used for foam end-uses. 

8.1 Acute Exposure at Spray Foam Application

There is potential for general population exposure to Formacel® 1100 during rigid polyurethane spray 

foaming operations when performed in buildings with occupants. To ensure that these instances do not 

present a risk to the general population, EPA recommends that the contractors consult the building 

management prior to commencing foam blowing activities. The building management should also ensure 

that building occupants are made aware that foam blowing is about to occur and should suggest the 

occupants leave the premises until foam blowing is complete.

8.2 Chronic Exposure during Lifetime Foam-Blowing Agent Releases 

There is the potential for chronic general population exposures to foam-blowing agents during the lifetime 

of the foam in which they are used, because these agents can slowly leak from the foam over time. As a 

result, in locations where persons are regularly present for extended periods, such as a home or apartment, 

the persons could be exposed to very low levels of Formacel® 1100 over time. Based on the foam 

blowing end-uses proposed for Formacel® 1100, the maximum annual operating leak rate of Formacel®

1100 during the lifetime of the foam (i.e., after manufacture and before disposal) is anticipated to be 1.5%

(see Table 3), resulting in very minimal exposure concentrations well below the WEEL of 500 ppm. Due 

to the low toxicity of Formacel® 1100 and minimal expected release, EPA believes that such exposures 

do not pose a significant toxicity risk, and thus, Formacel® 1100 is not expected to cause a significant 

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

end-uses.

9. AQUATIC AND ECOSYSTEM IMPACT ASSESSMENT

To assess potential environmental risks from releases of the proposed substitute to water and aquatic life, 

EPA reviewed studies evaluating the ecotoxicity of Formacel® 1100. Notably, the studies indicated that 

the chemical has high volatility and would very likely not remain in surface water at concentrations high 

enough to be considered toxic to the environment. Mitsubishi (2011) indicated that Formacel® 1100

could be toxic to fish. However, the study authors had to continually replenish the Formacel® 1100 in the 

samples in order to try to maintain the test concentrations of 100 mg/L and observe these effects. The 

submitter has indicated that releases of the proposed substitute to surface water are expected to be less 

than [ ] grams/hour, in accordance with facility permit limits. Because releases are expected to be minimal 

and highly volatile, toxic concentrations of Formacel® 1100 are not likely to occur under normal 

manufacture and use of the proposed substitute. Based on these considerations, EPA believes that 

Formacel® 1100 will not pose significant environmental risks through contact with aquatic life. 
Final—July 2, 2015

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10. REFERENCES

DuPont Chemicals and Fluoroproducts. 2014. Letter from Toxicology Excellence for Risk Assessment on 

the Workplace Environmental Exposure Level (WEEL) developed by the Occupational Alliance for Risk 

Science for Formacel® 1100. September 12, 2014

DuPont Chemicals and Fluoroproducts. 2012a. Performance Update on Formacel® 1100– a Zero ODP 

and Low GWP Foam Expansion Agent. May 8-9, 2012. Available at: 

< http://www2.dupont.com/Formacel/en_US/assets/downloads/20120508_FEA1100_Performance_Update_charts.pdf>

DuPont Chemicals and Fluoroproducts. 2012b. Response to Incomplete SNAP Submission for 

Formacel® 1100. September 5, 2012.

DuPont Chemicals and Fluoroproducts. 2011a. Formacel® 1100 Foam Stability Testing. September 9, 

2011.

DuPont Chemicals and Fluoroproducts. 2011b. Response to Incomplete SNAP Submission for 

Formacel® 1100. August 15, 2011.

DuPont Chemicals and Fluoroproducts. 2011c. SNAP Submission to EPA for Formacel® 1100. August 3, 

2011. 

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

Use of Substitutes for Class I Ozone-depleting Substances: Foam Blowing Agents. Stratospheric 

Protection Division. March, 1994.

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>

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.

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

Mitsubishi Chemical Medience Corporation. 2011. Acute Toxicity Test of 1100 with Medaka (Oryzias 

latipes). Study Number A100566. Submitted to DuPont-Mitsui Fluorochemicals, Co., Ltd. August 26, 

2011.

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

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.