Document ID: EPA-HQ-OAR-2003-0118-1710
Agency: epa
Document Type: Rule
Title: Protection of Stratospheric Ozone: Determination 36 for Significant New Alternatives Policy Program
Posted Date: 2020-12-11T05:00Z

[Federal Register Volume 85, Number 239 (Friday, December 11, 2020)]
[Rules and Regulations]
[Pages 79863-79872]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-23861]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 82

[EPA-HQ-OAR-2003-0118; FRL-10016-19-OAR]
RIN 2060-AG12

Protection of Stratospheric Ozone: Determination 36 for 
Significant New Alternatives Policy Program

AGENCY: Environmental Protection Agency (EPA).

ACTION: Determination of acceptability.

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SUMMARY: This determination of acceptability expands the list of 
acceptable substitutes pursuant to the U.S. Environmental Protection 
Agency's (EPA) Significant New Alternatives Policy (SNAP) program. This 
action lists as acceptable additional substitutes for use in the 
refrigeration and air conditioning, foam blowing, and fire suppression 
sectors.

DATES: This determination is applicable on December 11, 2020.

ADDRESSES: The EPA established a docket for this action under Docket ID 
No. EPA-HQ-OAR-2003-0118 (continuation of Air Docket A-91-42). All 
electronic documents in the docket

[[Page 79864]]

are listed in the index at www.regulations.gov. Although listed in the 
index, some information is not publicly available, i.e., Confidential 
Business Information (CBI) or other information whose disclosure is 
restricted by statute. Publicly available docket materials are 
available either electronically at www.regulations.gov or in hard copy 
at the EPA Air Docket (Nos. A-91-42 and EPA-HQ-OAR-2003-0118), EPA 
Docket Center (EPA/DC), William J. Clinton West, Room 3334, 1301 
Constitution Avenue NW, Washington, DC 20460. The telephone number for 
the Public Reading Room is (202) 566-1744, and the telephone number for 
the Air Docket is (202) 566-1742. Out of an abundance of caution for 
members of the public and our staff, the EPA Docket Center and Reading 
Room are closed to public visitors, with limited exceptions, to reduce 
the risk of transmitting COVID-19. Our Docket Center staff will 
continue to provide remote customer service via email, phone, and 
webform.

FOR FURTHER INFORMATION CONTACT: Chenise Farquharson by telephone at 
(202) 564-7768, by email at Farquharson.chenise@epa.gov, or by mail at 
U.S. Environmental Protection Agency, Mail Code 6205T, 1200 
Pennsylvania Avenue NW, Washington, DC 20460. Overnight or courier 
deliveries should be sent to the office location at 1201 Constitution 
Avenue NW, Washington, DC 20004.

SUPPLEMENTARY INFORMATION:

Table of Contents

I. Listing of New Acceptable Substitutes
    A. Refrigeration and Air Conditioning
    B. Foam Blowing
    C. Fire Suppression and Explosion Protection
Appendix A: Summary of Decisions for New Acceptable Substitutes

I. Listing of New Acceptable Substitutes

    This action is listing as acceptable additional substitutes for use 
in the refrigeration and air conditioning, foam blowing, and fire 
suppression sectors. This action presents EPA's most recent decision to 
list as acceptable several substitutes in different SNAP end-uses. New 
substitutes are:
     Hydrochlorofluoroolefin (HCFO)-1233zd(E) in industrial 
process refrigeration (new and retrofit equipment);
     R-515B in centrifugal and positive displacement chillers 
and industrial process air conditioning (new equipment);
     Blends of 10 to 99 percent by weight hydrofluoroolefin 
(HFO)-1336mzz(Z) and the remainder hydrofluorocarbon (HFC)-152a in 
polystyrene: Extruded boardstock and billet;
     HFO-1336mzz(E) in a number of foam blowing end-uses;
     Methylal in rigid polyurethane (PU) spray foam (high-
pressure two-component, low-pressure two-component, and one-component 
foam sealants); and
     HCFO-1233zd(E)/C6-perfluoroketone blend in total flooding 
fire suppression (normally occupied and unoccupied spaces).
    EPA's review of certain substitutes listed in this document is 
pending for other uses. Listing decisions in the end-uses and 
applications in this document do not prejudge EPA's listings of these 
substitutes for other end-uses. The substitutes being added through 
this action to the acceptable lists for specific end-uses have a 
similar or lower risk than other substitutes already listed as 
acceptable in those end-uses. However, certain substitutes may have a 
higher overall risk than certain other substitutes already listed as 
acceptable or acceptable subject to restrictions. In such cases, those 
already-listed alternatives have not yet proved feasible in those 
specific end-uses to date.
    For additional information on SNAP, visit the SNAP portion of EPA's 
Ozone Layer Protection website at: www.epa.gov/snap. Copies of the full 
lists of acceptable substitutes for ozone-depleting substances (ODS) in 
all industrial sectors are available at www.epa.gov/snap/substitutes-sector. For more information on the Agency's process for administering 
the SNAP program or criteria for evaluation of substitutes, refer to 
the initial SNAP rulemaking published March 18, 1994 (59 FR 13044), and 
the regulations codified at 40 CFR part 82, subpart G. SNAP decisions 
and the appropriate Federal Register citations are found at: 
www.epa.gov/snap/snap-regulations. Substitutes listed as unacceptable; 
acceptable, subject to narrowed use limits; or acceptable, subject to 
use conditions are also listed in the appendices to 40 CFR part 82, 
subpart G.
    The sections below discuss each substitute listing in detail. 
Appendix A contains tables summarizing each listing decision in this 
action. The statements in the ``Further Information'' column in the 
tables provide additional information but these are not legally binding 
under section 612 of the Clean Air Act (CAA). Although you are not 
required to follow recommendations in the ``Further Information'' 
column of the table to use a substitute consistent with section 612 of 
the CAA, some of these statements may refer to obligations that are 
enforceable or binding under federal or state programs other than the 
SNAP program. The identification of other enforceable or binding 
requirements should not be construed as a comprehensive list of such 
obligations. In many instances, the information simply refers to 
standard operating practices in existing industry standards and/or 
building codes. When using these substitutes in the identified end-use, 
EPA strongly encourages you to apply the information in the ``Further 
Information'' column. Many of these recommendations, if adopted, would 
not require significant changes to existing operating practices.
    You can find submissions to EPA for the substitutes listed in this 
document, as well as other materials supporting the decisions in this 
action, in Docket EPA-HQ-OAR-2003-0118 at www.regulations.gov.

A. Refrigeration and Air Conditioning

1. HCFO-1233zd(E)
    EPA's decision: EPA finds HCFO-1233zd(E) acceptable as a substitute 
for use in:

 Industrial Process Refrigeration (new and retrofit equipment)

    HCFO-1233zd(E), marketed under the trade name SolsticeTM 
N12 Refrigerant, is also known as trans-1-chloro-3,3,3-trifluoroprop-1-
ene (Chemical Abstracts Service Registry Number [CAS Reg. No.] 102687-
65-0).
    You may find a copy of the applicant's submission, with CBI 
redacted, providing the required health and environmental information 
for this substitute in this end-use in Docket EPA-HQ-OAR-2003-0118 at 
www.regulations.gov under the name, ``Supporting Materials for Notice 
36 Listing of HCFO-1233zd(E) in Refrigeration and Air Conditioning. 
SNAP Submission Received June 6, 2019.'' EPA performed an assessment to 
examine the health and environmental risks of this substitute. This 
assessment is available in Docket EPA-HQ-OAR-2003-0118: ``Risk Screen 
on Substitutes in Industrial Process Refrigeration. Substitute: HCFO-
1233zd(E).''
    EPA previously listed HCFO-1233zd(E) as acceptable for use in 
several refrigeration and air conditioning and foam blowing end-uses 
(August 10, 2012, 77 FR 47768; October 21, 2014, 79 FR 62863).
    Environmental information: HCFO-1233zd(E) has an ozone depletion 
potential (ODP) of less than 0.0004 and a global warming potential 
(GWP) of

[[Page 79865]]

3.7.\1\ HCFO-1233zd(E) is excluded from the definition of volatile 
organic compounds (VOC) under CAA regulations (see 40 CFR 51.100(s)) 
addressing the development of state implementation plans (SIPs) to 
attain and maintain the National Ambient Air Quality Standards (NAAQS). 
Knowingly venting or releasing this refrigerant blend is limited by the 
venting prohibition under section 608(c)(2) of the CAA, codified at 40 
CFR 82.154(a)(1).
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    \1\ WMO (World Meteorological Organization), Scientific 
Assessment of Ozone Depletion: 2018, Global Ozone Research and 
Monitoring Project--Report No. 58, 588 pp., Geneva, Switzerland, 
2018. Available at: https://ozone.unep.org/sites/default/files/2019-05/SAP-2018-Assessment-report.pdf. In this action, the 100-year GWP 
values are used.
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    Flammability information: HCFO-1233zd(E) is not flammable.
    Toxicity and exposure data: Potential health effects of exposure to 
this substitute include drowsiness or dizziness. The substitute may 
also irritate the skin or eyes or cause frostbite. The substitute could 
cause asphyxiation if air is displaced by vapors in a confined space. 
These potential health effects are common to many refrigerants.
    The American Industrial Hygiene Association (AIHA) has established 
a Workplace Environmental Exposure Limit (WEEL) of 800 ppm on an eight-
hour time-weighted average (8-hr TWA) for HCFO-1233zd(E). EPA 
anticipates that users will be able to meet the WEEL and address 
potential health risks by following requirements and recommendations in 
the manufacturer's safety data sheet (SDS), American Society of 
Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) 
Standard 15, and other safety precautions common to the refrigeration 
and air conditioning industry.
    Comparison to other substitutes in these end-uses: HCFO-1233zd(E) 
has an ODP of less than 0.0004, comparable to or less than other listed 
substitutes in this end-use with ODPs ranging from zero to 0.098.
    For industrial process refrigeration, HCFO-1233zd(E)'s GWP of about 
3.7 is comparable to or lower than that of other acceptable substitutes 
such as ammonia absorption for new equipment and carbon dioxide 
(CO2), R-450A, R-513A and hydrofluorocarbon (HFC)-23 for new 
and retrofit equipment, with GWPs \2\ ranging from zero to 14,800.
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    \2\ Unless otherwise stated, all GWPs in this document are 100-
year values from: IPCC, 2007: 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., Qin, D., Manning, M., Chen, Z., Marquis, M., Averyt, 
K.B., Tignor M., and Miller, H.L. (eds.)]. Cambridge University 
Press, Cambridge, United Kingdom and New York, NY, USA. This 
document is accessible at www.ipcc.ch/publications_and_data/ar4/wg1/
en/contents.html.
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    Flammability and toxicity risks are comparable to or lower than 
flammability and toxicity risks of other available substitutes in the 
same end-use. Toxicity risks can be minimized by use consistent with 
the AIHA WEEL, ASHRAE 15, and other industry standards, recommendations 
in the manufacturer's SDS, and other safety precautions common in the 
refrigeration and air conditioning industry.
    EPA finds HCFO-1233zd(E) acceptable in the industrial process 
refrigeration (new and retrofit equipment) end-use because it does not 
pose greater overall environmental and human health risk than other 
available substitutes in the same end-use.
2. R-515B
    EPA's decision: EPA finds R-515B acceptable as a substitute for use 
in:

 Centrifugal chillers (new equipment)
 Positive displacement chillers (new equipment)
 Industrial process air conditioning (new equipment)

    R-515B is a weighted blend of 91.1 percent HFO-1234ze(E), which is 
also known as trans-1,3,3,3-tetrafluoroprop-1-ene (CAS Reg. No. 29118-
24-9) and 8.9 percent HFC-227ea, also known as 1,1,1,2,3,3,3-
heptafluoropropane (CAS Reg. No. 431-89-0).
    You may find a copy of the applicant's submission, with CBI 
redacted, providing the required health and environmental information 
for this substitute in these end-uses in Docket EPA-HQ-OAR-2003-0118 at 
www.regulations.gov under the name, ``Supporting Materials for Notice 
36 Listing of R-515B in Refrigeration and Air Conditioning. SNAP 
Submission Received September 6, 2019.'' EPA performed an assessment to 
examine the health and environmental risks of this substitute. This 
assessment is available in Docket EPA-HQ-OAR-2003-0118: ``Risk Screen 
on Substitutes in Centrifugal and Positive Displacement Chillers and 
Industrial Process Air Conditioning. Substitute: R-515B.''
    Environmental information: R-515B has an ODP of zero. Its 
components, HFO-1234ze(E) and HFC-227ea, have a GWP of less than one 
\3\ and 3,220, respectively. If these values are weighted by mass 
percentage, then R-515B has a GWP of about 287. The components of R-
515B are excluded from the definition of VOC under CAA regulations (see 
40 CFR 51.100(s)) addressing the development of SIPs to attain and 
maintain the NAAQS. Knowingly venting or releasing this refrigerant 
blend is limited by the venting prohibition under section 608(c)(2) of 
the CAA, codified at 40 CFR 82.154(a)(1).
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    \3\ WMO (World Meteorological Organization), Scientific 
Assessment of Ozone Depletion: 2018, Global Ozone Research and 
Monitoring Project--Report No. 58, 588 pp., Geneva, Switzerland, 
2018. Available at: https://ozone.unep.org/sites/default/files/2019-05/SAP-2018-Assessment-report.pdf.
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    Flammability information: R-515B is not flammable.
    Toxicity and exposure data: Potential health effects of exposure to 
this substitute include drowsiness or dizziness. The substitute may 
also irritate the skin or eyes or cause frostbite. The substitute could 
cause asphyxiation if air is displaced by vapors in a confined space. 
These potential health effects are common to many refrigerants.
    For the components of R-515B, the AIHA has established WEELs of 800 
ppm and 1000 ppm as an 8-hr TWA for HFO-1234ze(E) and HFC-227ea, 
respectively. The manufacturer of R-515B recommends an acceptable 
exposure limit (AEL) for the blend of 810 ppm as an 8-hr TWA. EPA 
anticipates that users will be able to meet each of the WEELs, the 
manufacturer's AEL, and address potential health risks by following 
requirements and recommendations in the manufacturer's SDS, in ASHRAE 
Standard 15, and other safety precautions common to the refrigeration 
and air conditioning industry.
    Comparison to other substitutes in these end-uses: R-515B has an 
ODP of zero, comparable to or less than other listed substitutes in 
these end-uses, with ODPs ranging from zero to 0.055.
    For centrifugal and positive displacement chillers, R-515B's GWP of 
about 287 is comparable to or lower than that of other acceptable 
substitutes for new equipment, such as ammonia absorption, 
CO2, HFO-1336mzz(Z), and R-513A, with GWPs ranging from zero 
to 630.
    For industrial process air conditioning, R-515B's GWP of about 287 
is comparable to or lower than that of other acceptable substitutes for 
new equipment, such as ammonia absorption, CO2, HFO-
1336mzz(Z), R-134a, and R-507A, with GWPs ranging from zero to 3,985.
    Flammability and toxicity risks are comparable to or lower than 
flammability and toxicity risks of other available substitutes in the 
same end-uses. Toxicity risks can be minimized by use consistent with 
the AIHA WEEL, manufacturer's AEL, ASHRAE 15, and other industry 
standards,

[[Page 79866]]

recommendations in the manufacturer's SDS, and other safety precautions 
common in the refrigeration and air conditioning industry.
    EPA finds R-515B acceptable in the centrifugal chillers, positive 
displacement chillers, and industrial process air conditioning end-uses 
because it does not pose greater overall environmental and human health 
risk than other available substitutes in the same end-uses.

B. Foam Blowing

1. Blends of 10 to 99 percent by weight HFO-1336mzz(Z) and the 
remainder HFC-152a
    EPA's decision: EPA finds blends of 10 to 99 percent by weight HFO-
1336mzz(Z) andthe remainder HFC-152a (``HFO-1336mzz(Z)/HFC-152a 
blends'') acceptable as a substitute for use as a blowing agent in:

 Polystyrene: Extruded boardstock and billet

    These blends range in composition from 10 percent HFO-1336mzz(Z) 
and 90 percent HFC-152a to 99 percent HFO-1336mzz(Z) and 1 percent HFC-
152a. Accordingly, these blends are also referred to as blends of 10 to 
99 percent by weight HFO-1336mzz(Z) and the remainder HFC-152a in this 
action. HFO-1336mzz(Z) is an HFO and is also called (Z)-1,1,1,4,4,4-
hexafluorobut-2-ene or cis-1,1,1,4,4,4-hexafluorobut-2-ene (CAS Reg. 
No. 692-49-9); it also goes by the trade names of FEA-1100 or 
Formacel[supreg] 1100. HFC-152a is an HFC and is also called ethane, 
1,1-difluoro (CAS Reg. No. 75-37-6).
    You may find a copy of the applicant's submission, with CBI 
redacted, providing the required health and environmental information 
for this substitute in this end-use in Docket EPA-HQ-OAR-2003-0118 at 
www.regulations.gov under the name, ``SNAP Information Notice for 
Blends of 10 to 99 percent by Weight HFO-1336mzz(Z) and the Remainder 
HFC-152a as a Foam Blowing Agent. SNAP Submission Received October 10, 
2019.'' EPA has performed an assessment to examine the health and 
environmental risks of this substitute. This assessment is available in 
docket EPA-HQ-OAR-2003-0118 under the name ``Risk Screen on Substitutes 
for Use in Extruded Polystyrene Boardstock and Billet Foam Substitute: 
HFO-1336mzz(Z) and HFC-152a Blends .''
    Environmental information: These HFO-1336mzz(Z)/HFC-152a blends 
have an ODP of zero. Their components, HFO-1336mzz(Z) and HFC-152a, 
have GWPs of about two \4\ and 124, respectively. If these values are 
weighted by mass percentage, then the blends range in GWP from about 
three to about 110. Both components of the blends are excluded from the 
definition of VOC under CAA regulations (see 40 CFR 51.100(s)) 
addressing the development of SIPs to attain and maintain the NAAQS.
---------------------------------------------------------------------------

    \4\ WMO (World Meteorological Organization), Scientific 
Assessment of Ozone Depletion: 2018, Global Ozone Research and 
Monitoring Project--Report No. 58, 588 pp., Geneva, Switzerland, 
2018. Available at: https://ozone.unep.org/sites/default/files/2019-05/SAP-2018-Assessment-report.pdf.
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    Flammability information: The component HFC-152a is moderately 
flammable. HFO-1336mzz(Z) is not flammable at standard temperature and 
pressure using the standard test method ASTM E681. Certain of these 
HFO-1336mzz(Z)/HFC-152a blends are flammable, depending on the specific 
composition. For example, blends containing less than 91.5 percent HFO-
1336mzz(Z) and more than 8.5 percent HFC-152a by weight are flammable.
    Toxicity and exposure data: Potential health effects of this 
substitute include skin or eye irritation or frostbite. At sufficiently 
high concentrations, the substitute may cause irregular heartbeat. The 
substitute could cause asphyxiation if air is displaced by vapors in a 
confined space. These potential health effects are common to many foam 
blowing agents. The EPA anticipates that these HFO-1336mzz(Z)/HFC-152a 
blends will be used consistent with the recommendations specified in 
the SDS.
    The AIHA has established a WEEL of 1,000 ppm as an 8-hr TWA for 
HFC-152a, and the WEEL committee of the Occupational Alliance for Risk 
Science (OARS) has established a WEEL of 500 ppm for HFO-1336mzz(Z). 
EPA anticipates that users will be able to meet the AIHA and OARS WEELs 
and will address potential health risks by following requirements and 
recommendations in the manufacturer's SDSs and other safety precautions 
common to the foam blowing industry.
    Comparison to other foam blowing agents: These HFO-1336mzz(Z)/HFC-
152a blends have an ODP of zero, comparable to all other acceptable 
substitutes in this end-use, such as HFC-152a, HFO-1234ze(E), methyl 
formate, and CO2. These HFO-1336mzz(Z)/HFC-152a blends' GWPs 
from about three to 110 is lower than or comparable to those of other 
acceptable substitutes in the same end-use for which we are finding it 
acceptable, such as HFC-152a, HFO-1234ze(E), light saturated 
hydrocarbons C3-C6 and methyl formate, with respective GWPs of 124, 
one, \5\ less than one,\6\ and 11.\7\ Flammability and toxicity risks 
are comparable to or lower than flammability and toxicity risks of 
other available substitutes in the same end-use. Toxicity risks can be 
minimized by use consistent with the AIHA's and OARS's WEELs, 
recommendations in the SDS, and other safety precautions common in the 
foam blowing industry.
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    \5\ WMO (World Meteorological Organization), Scientific 
Assessment of Ozone Depletion: 2018, Global Ozone Research and 
Monitoring Project--Report No. 58, 588 pp., Geneva, Switzerland, 
2018. Available at: https://ozone.unep.org/sites/default/files/2019-05/SAP-2018-Assessment-report.pdf.
    \6\ Ibid.
    \7\ Ibid.
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    EPA finds blends of 10 to 99 percent by weight HFO-1336mzz(Z) and 
the remainder HFC-152a acceptable in the polystyrene: extruded 
boardstock and billet end-use because they do not pose greater overall 
environmental and human health risk than other available substitutes in 
the same end-use.
2. HFO-1336mzz(E)
    EPA's decision: EPA finds HFO-1336mzz(E) acceptable as a substitute 
for use in:

 Flexible Polyurethane (PU)
 Integral skin PU
 Rigid PU: Appliance
 Rigid PU: Commercial refrigeration
 Rigid PU and polyisocyanurate laminated boardstock
 Rigid PU: Sandwich panels
 Rigid PU: Slabstock and other
 Rigid PU: Spray--high-pressure two-component
 Rigid PU: Spray--low-pressure two-component
 Rigid PU: Spray--one-component foam sealants

    HFO-1336mzz(E) is also known as (2E)-1,1,1,4,4,4-hexafluoro-2-
butene and trans-1,1,1,4,4,4-hexafluoro-2-butene (CAS Reg. No. 66711-
86-2). It is marketed under the trade names OpteonTM 1150 
and FormacelTM 1150.
    You may find a copy of the applicant's submission, with CBI 
redacted, providing the required health and environmental information 
for this substitute in these end-uses in Docket EPA-HQ-OAR-2003-0118 at 
www.regulations.gov under the name, ``Supporting Documentation for 
Notice 36 Listing of HFO-1336mzz(E) in Foam Blowing. SNAP Submission 
Received December 5, 2018.'' EPA performed assessments to examine the 
health and environmental risks of this substitute. These assessments 
are available in Docket EPA-HQ-OAR-2003-0118 under the following names:

 ``Foam Blowing Sector--Risk Screen on Substitutes in Rigid 
Polyurethane

[[Page 79867]]

Appliance; Rigid Polyurethane Commercial Refrigeration; Rigid 
Polyurethane Sandwich Panels; Rigid Polyurethane & Polyisocyanurate 
Laminate Boardstock; Rigid Polyurethane Slabstock and Other; Flexible 
Polyurethane; Integral Skin Polyurethane--Substitute: HFO-1336mzz(E)''
 ``Foam Blowing Sector--Risk Screen on Substitutes in Rigid 
Polyurethane Spray Foam--Substitute: HFO-1336mzz(E)''

    Environmental information: HFO-1336mzz(E) has an ODP of zero. It 
has a GWP of about 16.\8\ Under CAA regulations (see 40 CFR 51.100(s)) 
defining VOC for the purpose of addressing the development of SIPs to 
attain and maintain the NAAQS, HFO-1336mzz(E) would be considered a 
VOC. That definition provides that ``any compound of carbon'' which 
``participates in atmospheric photochemical reactions'' is considered a 
VOC unless expressly excluded in that provision based on a 
determination of ``negligible photochemical reactivity.'' The 
manufacturer has petitioned the EPA to exclude HFO-1336mzz(E) from the 
definition of VOC under those regulations based on its claim that the 
chemical exhibits low photochemical reactivity. EPA has not yet taken 
action on that petition. EPA notes for informational purposes that this 
substitute is subject to a Toxic Substances Control Act (TSCA) section 
5(e) Consent Order and a TSCA section 5(a)(2) Significant New Use Rule 
(SNUR).
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    \8\ WMO (World Meteorological Organization), Scientific 
Assessment of Ozone Depletion: 2018, Global Ozone Research and 
Monitoring Project--Report No. 58, 588 pp., Geneva, Switzerland, 
2018. Available at: https://www.esrl.noaa.gov/csl/assessments/ozone/2018/.
---------------------------------------------------------------------------

    EPA anticipates that HFO-1336mzz(E) will be used consistent with 
the recommendations specified in the SDS. The OARS WEEL committee 
recommends a WEEL for the workplace of 400 ppm on an 8-hour TWA. EPA 
anticipates that users will be able to meet the WEEL and address 
potential health risks by following requirements and recommendations in 
the SDS and other safety precautions common to the foam blowing 
industry.
    Comparison to other substitutes in these end-uses: HFO-1336mzz(E) 
has an ODP of zero, comparable to or lower than that for other listed 
substitutes in these end-uses, with ODPs ranging from zero to 0.02.
    HFO-1336mzz(E)'s GWP of about 16 is lower than that of other 
acceptable substitutes in the listed end-uses, such as HFC-152a with a 
GWP of 124. HFO-1336mzz(E)'s GWP is higher than or comparable to the 
GWPs of other acceptable substitutes for these end-uses, such as HFO-
1336mzz(Z), methyl formate, saturated light hydrocarbons C3-C6,\9\ and 
trans-1-chloro-3,3,3-trifluoroprop-1-ene with GWPs ranging from less 
than one to approximately 11.
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    \9\ That is, hydrocarbons with single bonds with three to six 
carbons, such as propane, isobutane, pentane, isopentane, 
cyclopentane, and hexane.
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    Flammability and toxicity risks are comparable to or lower than 
flammability and toxicity risks of other available substitutes in the 
same end-use. Toxicity risks can be minimized by use consistent with 
the OARS WEEL, recommendations in the manufacturer's SDS, and other 
safety precautions common in the foam blowing industry; moreover, those 
risks are common to many foam blowing agents, including many of those 
already listed as acceptable under SNAP for these end-uses.
    EPA anticipates that HFO-1336mzz(E) will be used consistent with 
the recommendations specified in the SDS. The OARS WEEL committee 
recommends a WEEL for the workplace of 400 ppm on an 8-hour TWA. EPA 
anticipates that users will be able to meet the WEEL and address 
potential health risks by following requirements and recommendations in 
the SDS and other safety precautions common to the foam blowing 
industry.
    Comparison to other substitutes in these end-uses: HFO-1336mzz(E) 
has an ODP of zero, comparable to or lower than that for other listed 
substitutes in these end-uses, with ODPs ranging from zero to 0.02.
    HFO-1336mzz(E)'s GWP of about 16 is lower than that of other 
acceptable substitutes in the listed end-uses, such as HFC-152a with a 
GWP of 124. HFO-1336mzz(E)'s GWP is higher than or comparable to the 
GWPs of other acceptable substitutes for these end-uses, such as HFO-
1336mzz(Z), methyl formate, saturated light hydrocarbons C3-C6,\9\ and 
trans-1-chloro-3,3,3-trifluoroprop-1-ene with GWPs ranging from less 
than one to approximately 11.
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    \9\ That is, hydrocarbons with single bonds with three to six 
carbons, such as propane, isobutane, pentane, isopentane, 
cyclopentane, and hexane.
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    Flammability and toxicity risks are comparable to or lower than 
flammability and toxicity risks of other available substitutes in the 
same end-use. Toxicity risks can be minimized by use consistent with 
the OARS WEEL, recommendations in the manufacturer's SDS, and other 
safety precautions common in the foam blowing industry; moreover, those 
risks are common to many foam blowing agents, including many of those 
already listed as acceptable under SNAP for these end-uses.
    EPA finds HFO-1336mzz(E) acceptable in the end-uses listed above in 
section 1.B.2 because it does not pose greater overall environmental 
and human health risk than other available substitutes in the same end-
uses.
3. Methylal
    EPA's decision: EPA finds methylal acceptable as a substitute for 
use in:

     Rigid PU: Spray--high-pressure two-component
     Rigid PU: Spray--low-pressure two-component
     Rigid PU: Spray--one-component foam sealants

    Methylal is also called dimethoxymethane (CAS Reg. No. 109-87-5) 
and belongs to a class of chemicals referred to as acetals; it also 
goes by the trade name NovicellTM.
    You may find a copy of the applicant's submission, with CBI 
redacted, providing the required health and environmental information 
for this substitute in these end-uses in Docket EPA-HQ-OAR-2003-0118 at 
www.regulations.gov under the name, ``Supporting Materials for Notice 
36 Listing of Methylal in Foam Blowing. SNAP Submission Received April 
18, 2014.'' EPA performed an assessment to examine the health and 
environmental risks of this substitute. This assessment is available in 
Docket EPA-HQ-OAR-2003-0118 under the following name: ``Risk Screen on 
Substitutes for Use in Rigid Polyurethane Spray Foam Substitute: 
Methylal.''
    EPA previously listed methylal as acceptable for use as a foam-
blowing agent in a variety of foam blowing end-uses (October 21, 2014; 
79 FR 62863).
    Environmental information: Methylal has an ODP of zero and a GWP 
less than one.\10\ Under CAA regulations (see 40 CFR 51.100(s)) 
defining VOC for the purpose of addressing the development of SIPs to 
attain and maintain the NAAQS, methylal would be considered a VOC. That 
definition provides that ``any compound of carbon'' which 
``participates in atmospheric photochemical reactions'' is considered a 
VOC unless expressly excluded in that provision based on a 
determination of ``negligible photochemical reactivity.''
---------------------------------------------------------------------------

    \10\ WMO (World Meteorological Organization), Scientific 
Assessment of Ozone Depletion: 2018, Global Ozone Research and 
Monitoring Project--Report No. 58, 588 pp., Geneva, Switzerland, 
2018. Available at: https://ozone.unep.org/sites/default/files/2019-05/SAP-2018-Assessment-report.pdf.
---------------------------------------------------------------------------

    Flammability information: Methylal is flammable. Under the Globally

[[Page 79868]]

Harmonized System of Classification and Labelling of Chemicals, it is 
classified as a Class II flammable liquid and under the Occupational 
Safety and Health Administration's (OSHA's) regulations at 29 CFR 
1910.106, it is classified as a Class IB flammable liquid. Some 
specific blends of methylal with other blowing agents are flammable as 
formulated and should be handled with proper precautions, as specified 
by the manufacturer. EPA recommends that users follow all requirements 
and recommendations specified in the SDS and other safety precautions 
for use of flammable blowing agents used in the foam blowing industry. 
Use of methylal will require safe handling and shipping as prescribed 
by OSHA and the Department of Transportation (for example, using 
personal protective equipment (PPE) and following requirements for 
shipping hazardous materials at 49 CFR parts 170 through 173).
    Toxicity and exposure data: Potential health effects of exposure to 
this substitute include drowsiness or dizziness. Higher concentrations 
may cause central nervous system depression and loss of consciousness. 
The substitute may also irritate the skin or eyes. The substitute could 
cause asphyxiation if air is displaced by vapors in a confined space. 
These potential health effects are common to many foam-blowing agents.
    For methylal, the American Conference of Governmental Industrial 
Hygienists (ACGIH) has established a threshold limit value (TLV) of 
1,000 ppm on an 8-hr TWA. The National Institute of Occupational Safety 
and Health (NIOSH) has established a recommended exposure limit (REL) 
of 1,000 ppm for methylal on a 10-hour TWA. EPA anticipates that users 
will be able to meet workplace exposure limits (TLV and REL) and 
address potential health risks by following requirements and 
recommendations in the manufacturer's SDS and other safety precautions 
common to the foam-blowing industry.
    Comparison to other substitutes in these end-uses: Methylal has an 
ODP of zero, comparable to other listed substitutes in these end-uses, 
with ODPs ranging from zero to 0.012.
    Methylal's GWP of less than one is less than or comparable to the 
GWPs of other acceptable substitutes in the listed end-uses, including 
CO2, ExxsolTM blowing agents, HFC-152a, HFO-
1336mzz(Z), methyl formate,\11\ and trans-1-chloro-3,3,3-trifluoroprop-
1-ene, with GWPs ranging from less than 1 to approximately 124.\12\
---------------------------------------------------------------------------

    \11\ Originally listed under the trade name 
``ecomateTM'' in these end-uses. 69 FR 5803, October 4, 
2004.
    \12\ Except for HFC-152a, all the GWPs in this sentence are from 
WMO (World Meteorological Organization), Scientific Assessment of 
Ozone Depletion: 2018, Global Ozone Research and Monitoring 
Project--Report No. 58, 588 pp., Geneva, Switzerland, 2018. 
Available at: https://ozone.unep.org/sites/default/files/2019-05/SAP-2018-Assessment-report.pdf.
---------------------------------------------------------------------------

    Methylal's flammability risks are comparable to or lower than 
flammability risks of other available substitutes in the same end-uses, 
including ExxsolTM blowing agents and methyl formate. Other 
acceptable substitutes in these end-uses are nonflammable (e.g., 
CO2, HFO-1336mzz(Z), and trans-1-chloro-3,3,3-trifluoroprop-
1-ene.
    Toxicity risks are comparable to or lower than toxicity risks of 
other available substitutes in the same end-use. Toxicity risks can be 
minimized by use consistent with the ACGIH TLV, recommendations in the 
manufacturer's SDS, and other safety precautions common in the foam-
blowing industry.
    EPA finds methylal acceptable in the end-uses listed above in 
section I.B.3 because it does not pose greater overall environmental 
and human health risk than other available substitutes in the same end-
use.

C. Fire Suppression and Explosion Protection

HCFO-1233zd(E)/C6-perfluoroketone blend
    EPA's decision: EPA finds HCFO-1233zd(E)/C6-perfluoroketone blend 
acceptable as a substitute for:

 Total flooding (normally occupied and unoccupied spaces)

    HCFO-1233zd(E)/C6-perfluoroketone blend is a weighted blend of 50 
percent (E)-1-chloro-3,3,3-trifluoroprop-1-ene or HCFO-1233zd(E) (CAS 
Reg. No. 102687-65-0) and 50 percent C6-perfluoroketone (CAS Reg. No. 
756-13-8), also known as 1,1,1,2,2,4,5,5,5-nonafluoro-4-
(trifluoromethyl)-3-pentanone or FK-5-1-12. Both components are 
currently listed as acceptable under SNAP for use in this end-use. The 
blend is sold under the trade name SolsticeTM Quench 55.
    You may find a copy of the applicant's submission, with CBI 
redacted, providing the required health and environmental information 
for this substitute in this end-use in Docket EPA-HQ-OAR-2003-0118 at 
www.regulations.gov under the name, ``Supporting Documentation for 
Notice 36 Listing of HCFO-1233zd(E)/C6-perfluoroketone blend in Fire 
Suppression. SNAP Submission Received August 1, 2018.'' EPA performed 
an assessment to examine the health and environmental risks of this 
substitute. This assessment is available in Docket EPA-HQ-OAR-2003-
0118: ``Risk Screen on Substitutes for Total Flooding Systems in 
Normally Occupied and Unoccupied Spaces. Substitute: HCFO-1233zd(E)/C6-
perfluoroketone blend (SolsticeTM Quench 55).''
    Environmental information: The HCFO-1233zd(E) component of the 
blend has an ODP less than 0.0004 and a GWP of 3.7.\13\ The C6-
perfluoroketone component has no ODP and a GWP of less than one.\14\ 
The blend has an average ODP of less than 0.0002 and an average GWP of 
less than two. The HCFO-1233zd(E) component is excluded from the 
definition of VOC under CAA regulations (see 40 CFR 51.100(s)) 
addressing the development of SIPs to attain and maintain the NAAQS; 
the C6-perfluoroketone component falls within the definition of VOC in 
those regulations.
---------------------------------------------------------------------------

    \13\ WMO (World Meteorological Organization), Scientific 
Assessment of Ozone Depletion: 2018, Global Ozone Research and 
Monitoring Project--Report No. 58, 588 pp., Geneva, Switzerland, 
2018. Available at: https://ozone.unep.org/sites/default/files/2019-05/SAP-2018-Assessment-report.pdf.
    \14\ Ibid.
---------------------------------------------------------------------------

    Flammability information: HCFO-1233zd(E)/C6-perfluoroketone blend 
is not flammable.
    Toxicity and exposure data: Potential health effects of this 
substitute include serious eye and skin irritation. If eye or skin 
contact occurs, end users should flush the affected area with large 
amounts of water. If inhaled, end users should be removed and exposed 
to fresh air. The potential health effects of HCFO-1233zd(E)/C6-
perfluoroketone blend are unlikely to occur when following good 
industrial hygiene practices and the PPE and engineering control (e.g., 
ventilation) recommendations outlined in the SDSs for HCFO-1233zd(E)/
C6-perfluoroketone blend.
    The OARS has established a WEEL as an 8-hr TWA of 800 ppm for HCFO-
1233zd(E). The manufacturer of C6-perfluoroketone recommends an AEL of 
150 ppm on an 8-hr TWA. During installation or servicing of HCFO-
1233zd(E)/C6-perfluoroketone blend total flooding systems, exposure to 
the substitute is not likely if the instructions on system installation 
and servicing are adhered to; these instructions are included in 
manuals for the HCFO-

[[Page 79869]]

1233zd(E)/C6-perfluoroketone blend systems and the relevant industry 
standards (i.e., latest edition of the National Fire Protection 
Association [NFPA] 2001 Standard for Clean Agent Fire Extinguishing 
Systems and Underwriters' Laboratories [UL] 2166 Standard for 
Halocarbon Clean Agent Extinguishing System Units). In the event of an 
accidental release of the substitute from the total flooding system, 
potential acute exposures may be of concern. The design concentration 
is less than the cardiotoxic No Observed Adverse Effect Level of 8.66 
percent (86,600 ppm) for the blend. Appropriate protective measures 
should be taken, and proper training administered for the manufacture, 
clean-up and disposal of this product and for the installation and 
maintenance of the total flooding systems using this product.
    NFPA 2001 provides that in the case of accidental release in 
normally occupied spaces, required engineering controls as specified in 
NFPA 2001 should be employed to limit personnel exposure to clean agent 
discharges. Specifically, audible and visual pre-discharge alarms and a 
30-60 second time delay should be employed within the protected space 
to indicate the operation of the system and pending discharge to ensure 
egress for all personnel prior to activation. EPA's evaluation 
indicates that the use of HCFO-1233zd(E)/C6-perfluoroketone blend is 
not expected to pose a significant toxicity risk to personnel or the 
general population. In addition, the risks it may pose after exposure 
are common to many total flooding agents, including those already 
listed as acceptable under SNAP for this same end-use. EPA's review of 
the human health impacts of HCFO-1233zd(E)/C6-perfluoroketone blend, 
including the summary of available toxicity studies, is in the risk 
screen mentioned above in the docket for this action (EPA-HQ-OAR-2003-
0118).
    Protective gloves and tightly sealed goggles should be worn for 
installation and servicing activities to protect workers in any event 
of potential discharge of the substitute, accidental or otherwise. 
Filling or servicing operations should be performed in well-ventilated 
areas. Toxicity risks can be minimized by use consistent with NFPA 2001 
standard, recommendations in the SDS, and other safety precautions 
common in the fire suppression industry. EPA provides additional 
information on safe use of this substitute in the ``Further 
Information'' column of the table summarizing this listing for total 
flooding agents (see Appendix A).
    Comparison to other substitutes in this end-use: HCFO-1233zd(E)/C6-
perfluoroketone blend has an average ODP of less than 0.0002, 
comparable to or less than that for other listed substitutes in this 
end-use, with ODPs ranging from zero to 0.048.
    For total flooding agents, HCFO-1233zd(E)/C6-perfluoroketone 
blend's average GWP of less than two is lower than that of other 
acceptable substitutes, such as HFC-227ea and other HFCs, with GWPs 
which range from about 1,430 to 14,800. Other acceptable substitutes in 
this end-use, such as water, inert gases, and a number of powdered 
aerosol fire suppressants, have lower or comparable GWPs ranging from 
zero to seven.
    Toxicity risks can be minimized by use consistent with the NFPA 
2001 standard, recommendations in the SDS, and other safety precautions 
common in the fire suppression industry. The potential toxicity risks 
due to inhalation exposure are common to many total flooding agents, 
including those already listed as acceptable under SNAP for this same 
end-use. HCFO-1233zd(E)/C6-perfluoroketone blend is nonflammable, as 
are all other available total flooding agents.
    EPA finds HCFO-1233zd(E)/C6-perfluoroketone blend acceptable in the 
total flooding end-use because it does not pose greater overall 
environmental and human health risk than other available substitutes in 
this end-use.

List of Subjects in 40 CFR Part 82

    Environmental protection, Administrative practice and procedure, 
Air pollution control, Reporting and recordkeeping requirements.

Hans Christopher Grundler,
Director, Office of Atmospheric Programs.

    Note:  The following appendix will not appear in the Code of 
Federal Regulations:

APPENDIX A: SUMMARY OF DECISIONS FOR NEW ACCEPTABLE SUBSTITUTES

                                       Refrigeration and Air Conditioning
----------------------------------------------------------------------------------------------------------------
           End-use                Substitute            Decision                 Further information \1\
----------------------------------------------------------------------------------------------------------------
Centrifugal chillers (new      R-515B..........  Acceptable...........  This substitute is a blend of HFO-
 equipment).                                                             1234ze(E), which is also known as trans-
                                                                         1,3,3,3-tetrafluoroprop-1-ene (Chemical
                                                                         Abstracts Service Registry Number [CAS
                                                                         Reg. No.] 29118-24-9) and HFC-227ea,
                                                                         also known as 1,1,1,2,3,3,3-
                                                                         heptafluoropropane (CAS Reg. No. 431-89-
                                                                         0).
                                                                        R-515B has a 100-year global warming
                                                                         potential (GWP) of 287.
                                                                        The blend is not flammable.
                                                                        The American Industrial Hygiene
                                                                         Association (AIHA) has established
                                                                         Workplace Environmental Exposure Limits
                                                                         (WEELs) of 800 ppm and 1000 ppm on an
                                                                         eight-hour Time-Weighted Average (8-hr
                                                                         TWA), respectively, for HFO-1234ze(E)
                                                                         and for HFC-227ea.
                                                                        The manufacturer has established an
                                                                         Acceptable Exposure Limit (AEL) of 810
                                                                         ppm, on an 8-hr TWA for R-515B.
Industrial process air         R-515B..........  Acceptable...........  This substitute is a blend of HFO-
 conditioning (new equipment).                                           1234ze(E), which is also known as trans-
                                                                         1,3,3,3-tetrafluoroprop-1-ene (CAS Reg.
                                                                         No. 29118-24-9) and HFC-227ea, also
                                                                         known as 1,1,1,2,3,3,3-
                                                                         heptafluoropropane (CAS Reg. No. 431-89-
                                                                         0).
                                                                        R-515B has a GWP of 287.
                                                                        The blend is not flammable.
                                                                        The AIHA has established WEELs of 800
                                                                         ppm and 1000 ppm on an 8-hr TWA,
                                                                         respectively, for HFO-1234ze(E) and for
                                                                         HFC-227ea.
                                                                        The manufacturer has established an AEL
                                                                         of 810 ppm on an 8-hr TWA for R-515B.

[[Page 79870]]

 
Industrial process             HCFO-1233zd(E)..  Acceptable...........  HCFO-1233zd(E) is also known as trans-1-
 refrigeration (new and                                                  chloro-3,3,3-trifluoroprop-1-ene (CAS
 retrofit equipment).                                                    Reg. No 102687-65-0).
                                                                        HCFO-1233zd(E) has an ozone-depleting
                                                                         potential (ODP) of less than 0.0004 and
                                                                         a GWP of about 3.7.
                                                                        HCFO-1233zd(E) is nonflammable.
                                                                        The AIHA has established a WEEL of 800
                                                                         ppm on an 8-hr TWA for HCFO-1233zd(E).
Positive displacement          R-515B..........  Acceptable...........  This substitute is a blend of HFO-
 chillers (new equipment).                                               1234ze(E), which is also known as trans-
                                                                         1,3,3,3-tetrafluoroprop-1-ene (CAS Reg.
                                                                         No. 29118-24-9) and HFC-227ea, also
                                                                         known as 1,1,1,2,3,3,3-
                                                                         heptafluoropropane (CAS Reg. No. 431-89-
                                                                         0). R-515B has a GWP of 287.
                                                                        The blend is not flammable.
                                                                        The AIHA has established WEELs of 800
                                                                         ppm and 1000 ppm on an 8-hr TWA,
                                                                         respectively, for HFO-1234ze(E) and for
                                                                         HFC-227ea.
                                                                        The manufacturer has established an AEL
                                                                         of 810 ppm on an 8-hr TWA for R-515B.
----------------------------------------------------------------------------------------------------------------
\1\ Observe recommendations in the manufacturer's SDS and guidance for all listed refrigerants.

                                               Foam Blowing Agents
----------------------------------------------------------------------------------------------------------------
           End-use                Substitute            Decision                 Further information \1\
----------------------------------------------------------------------------------------------------------------
Extruded Polystyrene:          Blends of 10 to   Acceptable...........  HFO-1336mzz(Z) is also known as (2Z)-
 Boardstock and Billet.         99 percent by                            1,1,1,4,4,4-hexafluoro-2-butene and cis-
                                weight HFO-                              1,1,1,4,4,4-hexafluoro-2-butene (CAS
                                1336mzz(Z) and                           Reg. No. 692-49-9). HFC-152a is also
                                the remainder                            known as ethane, 1,1-difluoro (CAS Reg.
                                HFC-152a.                                No. 75-37-6). The blends range in
                                                                         composition from 10 percent HFO-
                                                                         1336mzz(Z) and 90 percent HFC-152a to
                                                                         99 percent HFO-1336mzz(Z) and 1 percent
                                                                         HFC-152a.
                                                                        These blends have 100-year global
                                                                         warming potentials (GWPs) from about
                                                                         three to about 110, depending on the
                                                                         specific composition. Certain blends of
                                                                         these compounds are flammable,
                                                                         depending on the specific composition.
                                                                         The American Industrial Hygiene
                                                                         Association (AIHA) has established a
                                                                         Workplace Environmental Exposure Limit
                                                                         (WEEL) of 1,000 ppm as an 8-hour Time-
                                                                         Weighted Average (8-hr TWA) for HFC-
                                                                         152a and Occupational Alliance for Risk
                                                                         Science (OARS) has established a WEEL
                                                                         of 500 ppm for HFO-1336mzz(Z).
Flexible Polyurethane (PU)...  HFO-1336mzz(E)..  Acceptable...........  HFO-1336mzz(E) is also known as (2E)-
                                                                         1,1,1,4,4,4-hexafluoro-2-butene and
                                                                         trans-1,1,1,4,4,4-hexafluoro-2-butene
                                                                         (CAS Reg. No. 66711-86-2).
                                                                        HFO-1336mzz(E) has a GWP of
                                                                         approximately 16.
                                                                        HFO-1336mzz(E) is nonflammable.
                                                                        The OARS recommends a WEEL for the
                                                                         workplace of 400 ppm on an 8-hr TWA.
                                                                        This substitute is subject to a Toxic
                                                                         Substances Control Act (TSCA) section
                                                                         5(e) Consent Order and a TSCA section
                                                                         5(a)(2) Significant New Use Rule
                                                                         (SNUR).
Integral skin PU.............  HFO-1336mzz(E)..  Acceptable...........  HFO-1336mzz(E) is also known as (2E)-
                                                                         1,1,1,4,4,4-hexafluoro-2-butene and
                                                                         trans-1,1,1,4,4,4-hexafluoro-2-butene
                                                                         (CAS Reg. No. 66711-86-2).
                                                                        HFO-1336mzz(E) has a GWP of
                                                                         approximately 16.
                                                                        HFO-1336mzz(E) is nonflammable.
                                                                        The OARS recommends a WEEL for the
                                                                         workplace of 400 ppm on an 8-hr TWA.
                                                                        This substitute is subject to a TSCA
                                                                         section 5(e) Consent Order and a TSCA
                                                                         section 5(a)(2) SNUR.
Rigid PU: Appliance..........  HFO-1336mzz(E)..  Acceptable...........  HFO-1336mzz(E) is also known as (2E)-
                                                                         1,1,1,4,4,4-hexafluoro-2-butene and
                                                                         trans-1,1,1,4,4,4-hexafluoro-2-butene
                                                                         (CAS Reg. No. 66711-86-2).
                                                                        HFO-1336mzz(E) has a GWP of
                                                                         approximately 16.
                                                                        HFO-1336mzz(E) is nonflammable.
                                                                        The OARS recommends a WEEL for the
                                                                         workplace of 400 ppm on an 8-hr TWA.
                                                                        This substitute is subject to a TSCA
                                                                         section 5(e) Consent Order and a TSCA
                                                                         section 5(a)(2) SNUR.
Rigid PU: Commercial           HFO-1336mzz(E)..  Acceptable...........  HFO-1336mzz(E) is also known as (2E)-
 refrigeration.                                                          1,1,1,4,4,4-hexafluoro-2-butene and
                                                                         trans-1,1,1,4,4,4-hexafluoro-2-butene
                                                                         (CAS Reg. No. 66711-86-2).
                                                                        HFO-1336mzz(E) has a GWP of
                                                                         approximately 16.
                                                                        HFO-1336mzz(E) is nonflammable.
                                                                        The OARS recommends a WEEL for the
                                                                         workplace of 400 ppm on an 8-hr TWA.
                                                                        This substitute is subject to a TSCA
                                                                         section 5(e) Consent Order and a TSCA
                                                                         section 5(a)(2) SNUR.

[[Page 79871]]

 
Rigid PU and polyisocyanurate  HFO-1336mzz(E)..  Acceptable...........  HFO-1336mzz(E) is also known as (2E)-
 laminated boardstock.                                                   1,1,1,4,4,4-hexafluoro-2-butene and
                                                                         trans-1,1,1,4,4,4-hexafluoro-2-butene
                                                                         (CAS Reg. No. 66711-86-2).
                                                                        HFO-1336mzz(E) has a GWP of
                                                                         approximately 16.
                                                                        HFO-1336mzz(E) is nonflammable.
                                                                        The OARS recommends a WEEL for the
                                                                         workplace of 400 ppm on an 8-hr TWA.
                                                                        This substitute is subject to a TSCA
                                                                         section 5(e) Consent Order and a TSCA
                                                                         section 5(a)(2) SNUR.
Rigid PU: Sandwich panels....  HFO-1336mzz(E)..  Acceptable...........  HFO-1336mzz(E) is also known as (2E)-
                                                                         1,1,1,4,4,4-hexafluoro-2-butene and
                                                                         trans-1,1,1,4,4,4-hexafluoro-2-butene
                                                                         (CAS Reg. No. 66711-86-2).
                                                                        HFO-1336mzz(E) has a GWP of
                                                                         approximately 16.
                                                                        HFO-1336mzz(E) is nonflammable.
                                                                        The OARS recommends a WEEL for the
                                                                         workplace of 400 ppm on an 8-hr TWA.
                                                                        This substitute is subject to a TSCA
                                                                         section 5(e) Consent Order and a TSCA
                                                                         section 5(a)(2) SNUR.
Rigid PU: Slabstock and other  HFO-1336mzz(E)..  Acceptable...........  HFO-1336mzz(E) is also known as (2E)-
                                                                         1,1,1,4,4,4-hexafluoro-2-butene and
                                                                         trans-1,1,1,4,4,4-hexafluoro-2-butene
                                                                         (CAS Reg. No. 66711-86-2).
                                                                        HFO-1336mzz(E) has a GWP of
                                                                         approximately 16.
                                                                        HFO-1336mzz(E) is nonflammable.
                                                                        The OARS recommends a WEEL for the
                                                                         workplace of 400 ppm on an 8-hr TWA.
                                                                        This substitute is subject to a TSCA
                                                                         section 5(e) Consent Order and a TSCA
                                                                         section 5(a)(2) SNUR.
Rigid PU: spray-high-pressure  HFO-1336mzz(E)..  Acceptable...........  HFO-1336mzz(E) is also known as (2E)-
 two-component.                                                          1,1,1,4,4,4-hexafluoro-2-butene and
                                                                         trans-1,1,1,4,4,4-hexafluoro-2-butene
                                                                         (CAS Reg. No. 66711-86-2).
                                                                        HFO-1336mzz(E) has a GWP of
                                                                         approximately 16.
                                                                        HFO-1336mzz(E) is nonflammable.
                                                                        The OARS recommends a WEEL for the
                                                                         workplace of 400 ppm on an 8-hr TWA.
                                                                        This substitute is subject to a TSCA
                                                                         section 5(e) Consent Order and a TSCA
                                                                         section 5(a)(2) SNUR.
Rigid PU: Spray-high-pressure  Methylal........  Acceptable...........  Methylal is also known as
 two-component.                                                          dimethoxymethane and belongs to a class
                                                                         of chemicals referred to as acetals
                                                                         (CAS Reg. No. 109-87-5).
                                                                        Methylal has a GWP of less than one.
                                                                        Methylal is flammable.
                                                                        The American Conference of Governmental
                                                                         Industrial Hygienists (ACGIH) has
                                                                         established a threshold limit value
                                                                         (TLV) of 1,000 ppm, on an 8-hr TWA for
                                                                         methylal. The National Institute of
                                                                         Occupational Safety and Health (NIOSH)
                                                                         has established a recommended exposure
                                                                         limit (REL) of 1,000 ppm for methylal
                                                                         on a 10-hour TWA.
Rigid PU: Spray-low-pressure   HFO-1336mzz(E)..  Acceptable...........  HFO-1336mzz(E) is also known as (2E)-
 two-component.                                                          1,1,1,4,4,4-hexafluoro-2-butene and
                                                                         trans-1,1,1,4,4,4-hexafluoro-2-butene
                                                                         (CAS Reg. No. 66711-86-2).
                                                                        HFO-1336mzz(E) has a GWP of
                                                                         approximately 16.
                                                                        HFO-1336mzz(E) is nonflammable.
                                                                        The OARS recommends a WEEL for the
                                                                         workplace of 400 ppm on an 8-hr TWA.
                                                                        This substitute is subject to a TSCA
                                                                         section 5(e) Consent Order and a TSCA
                                                                         section 5(a)(2) SNUR.
Rigid PU: Spray-low-pressure   Methylal........  Acceptable...........  Methylal is also known as
 two-component.                                                          dimethoxymethane and belongs to a class
                                                                         of chemicals referred to as acetals
                                                                         (CAS Reg. No. 109-87-5).
                                                                        Methylal has a GWP of approximately less
                                                                         than one.
                                                                        Methylal is flammable.
                                                                        ACGIH has established a TLV of 1,000 ppm
                                                                         on an 8-hr TWA for methylal. The NIOSH
                                                                         has established a REL of 1,000 ppm for
                                                                         methylal on a 10-hour TWA.
Rigid PU: Spray-one-component  HFO-1336mzz(E)..  Acceptable...........  HFO-1336mzz(E) is also known as (2E)-
 foam sealants.                                                          1,1,1,4,4,4-hexafluoro-2-butene and
                                                                         trans-1,1,1,4,4,4-hexafluoro-2-butene
                                                                         (CAS Reg. No. 66711-86-2).
                                                                        HFO-1336mzz(E) has a GWP of
                                                                         approximately 16.
                                                                        HFO-1336mzz(E) is nonflammable.
                                                                        The OARS recommends a WEEL for the
                                                                         workplace of 400 ppm on an 8-hr TWA.
                                                                        This substitute is subject to a TSCA
                                                                         section 5(e) Consent Order and a TSCA
                                                                         section 5(a)(2) SNUR.
Rigid PU: Spray-one-component  Methylal........  Acceptable...........  Methylal is also known as
 foam sealants.                                                          dimethoxymethane and belongs to a class
                                                                         of chemicals referred to as acetals
                                                                         (CAS Reg. No. 109-87-5).
                                                                        Methylal has a GWP of less than one.
                                                                        Methylal is flammable.
                                                                        ACGIH has established a TLV of 1,000 ppm
                                                                         on an 8-hr TWA for methylal. NIOSH has
                                                                         established a REL of 1,000 ppm for
                                                                         methylal on a 10-hour TWA.
----------------------------------------------------------------------------------------------------------------
\1\ Observe recommendations in the manufacturer's SDS and guidance for all listed foam blowing agents.

[[Page 79872]]

                                    Fire Suppression and Explosion Protection
----------------------------------------------------------------------------------------------------------------
           End-use                Substitute            Decision                   Further information
----------------------------------------------------------------------------------------------------------------
Total flooding (normally       HCFO-1233zd(E)/   Acceptable...........  HCFO-1233zd(E)/C6-perfluoroketone blend
 occupied and unoccupied        C6-                                      is a blend of (E)-
 spaces).                       perfluoroketone                          1[hyphen]chloro[hyphen]3,3,3[hyphen]tri
                                blend.                                   fluoroprop[hyphen]1[hyphen]ene or HCFO-
                                                                         1233zd(E) (CAS Reg. No. 102687-65-0)
                                                                         and C6-perfluoroketone (CAS Reg. No.
                                                                         756-13-8), also known as
                                                                         1,1,1,2,2,4,5,5,5[hyphen]nonafluoro[hyp
                                                                         hen]4[hyphen](trifluoromethyl)[hyphen]3
                                                                         [hyphen]pentanone or FK-5-1-12.
                                                                        This blend has an average ozone
                                                                         depletion potential (ODP) of <0.0002
                                                                         and an average 100-year global warming
                                                                         potential (GWP) of less than two.
                                                                        The blend is nonflammable.
                                                                        The Occupational Alliance for Risk
                                                                         Science (OARS) has established a
                                                                         Workplace Environmental Exposure Limit
                                                                         (WEEL) as an 8-hour Time-Weighted
                                                                         Average (8-hr TWA) of 800 ppm for HCFO-
                                                                         1233zd(E). The manufacturer of C6-
                                                                         perfluoroketone recommends an
                                                                         Acceptable Exposure Limit (AEL) of 150
                                                                         ppm on an 8-hr TWA. The cardiotoxic No
                                                                         Observed Adverse Effect Level (NOAEL)
                                                                         is 8.66 percent for the blend.
                                                                        Use of this agent should be in
                                                                         accordance with the safety guidelines
                                                                         in the latest edition of the National
                                                                         Fire Protection Association (NFPA) 2001
                                                                         Standard on Clean Agent Fire
                                                                         Extinguishing Systems. Safety features
                                                                         that are typical of total flooding
                                                                         systems such as pre-discharge alarms,
                                                                         time delays, and system abort switches
                                                                         should be provided, as directed by
                                                                         applicable Occupational Safety and
                                                                         Health Administration (OSHA)
                                                                         regulations and NFPA standards.
                                                                        For establishments manufacturing,
                                                                         installing and maintaining equipment
                                                                         using this agent, EPA recommends the
                                                                         following:
                                                                         In the case that HCFO-1233zd(E)/
                                                                         C6-perfluoroketone blend is inhaled,
                                                                         person(s) should be immediately removed
                                                                         and exposed to fresh air; if breathing
                                                                         is difficult, person(s) should seek
                                                                         medical attention.
                                                                         Eye wash and quick drench
                                                                         facilities should be available. In case
                                                                         of ocular exposure, person(s) should
                                                                         immediately flush the eyes, including
                                                                         under the eyelids, with water for 15
                                                                         minutes.
                                                                         In the case of dermal exposure,
                                                                         the safety data sheet (SDS) recommends
                                                                         that person(s) should immediately wash
                                                                         the affected area with water and remove
                                                                         all contaminated clothing to avoid
                                                                         irritation.
                                                                         Although unlikely, in case of
                                                                         ingestion of HCFO-1233zd(E)/C6-
                                                                         perfluoroketone blend, the person(s)
                                                                         should drink a cup of water, if fully
                                                                         conscious, and consult a physician
                                                                         immediately.
                                                                         Manufacturing space should be
                                                                         equipped with engineering controls,
                                                                         specifically an adequate exhaust
                                                                         ventilation system, to effectively
                                                                         mitigate potential occupational
                                                                         exposure.
                                                                         Employees responsible for
                                                                         chemical processing should wear the
                                                                         appropriate personnel protective
                                                                         equipment (PPE), such as protective
                                                                         gloves, tightly sealed goggles,
                                                                         protective work clothing, and suitable
                                                                         respiratory protection in case of
                                                                         release or insufficient ventilation.
                                                                         All spills should be cleaned up
                                                                         immediately in accordance with good
                                                                         industrial hygiene practices.
                                                                         Training for safe handling
                                                                         procedures should be provided to all
                                                                         employees that would be likely to
                                                                         handle containers of the agent or
                                                                         extinguishing units filled with the
                                                                         agent.
                                                                        See additional comments 1, 2, 3, 4, 5.
----------------------------------------------------------------------------------------------------------------
\1\ The EPA recommends that users consult Section VIII of the OSHA Technical Manual for information on selecting
  the appropriate types of personal protective equipment for all listed fire suppression agents. The EPA has no
  intention of duplicating or displacing OSHA coverage related to the use of personal protective equipment
  (e.g., respiratory protection), fire protection, hazard communication, worker training or any other
  occupational safety and health standard with respect to halon substitutes.
\2\ Use of all listed fire suppression agents should conform to relevant OSHA requirements, including 29 CFR
  part 1910, subpart L, sections 1910.160 and 1910.162.
\3\ Per OSHA requirements, protective gear (SCBA) should be available in the event personnel should reenter the
  area.
\4\ Discharge testing should be strictly limited to that which is essential to meet safety or performance
  requirements.
\5\ The agent should be recovered from the fire protection system in conjunction with testing or servicing, and
  recycled for later use or destroyed.

[FR Doc. 2020-23861 Filed 12-10-20; 8:45 am]
BILLING CODE 6560-50-P