This document summarizes research being conducted on flammable refrigerants. It discusses ASHRAE standards 34 and 15 which classify and set safety limits for refrigerants. New low global warming potential refrigerants that are mildly flammable require updates to these standards. Seven research projects funded by ASHRAE, DOE, and AHRTI aim to provide data to support revising standards to safely allow use of these alternative refrigerants. The research includes risk assessments of ignition events, guidelines for safe handling, leak and ignition testing, and determining appropriate charge limits. The goal is completing revisions to ASHRAE 15 by end of 2017 to include these alternative refrigerants.

1. Latest Technology in Refrigeration and Air Conditioning - XVII European Conference Milano, 9 - 10 June 2017
Flammable Refrigerants
Research and
Implementation
Walid Chakroun, Fellow ASHRAE
ASHRAE Vice President
Mechanical Engineering Department
Kuwait University

2. Latest Technology in Refrigeration and Air Conditioning - XVII European Conference Milano, 9 - 10 June 2017
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3. Latest Technology in Refrigeration and Air Conditioning - XVII European Conference Milano, 9 - 10 June 2017
What is Standard 34?
• Describes a shorthand way of naming
refrigerants and assigns safety
classifications and refrigerant
concentration limits based on toxicity and
flammability data.
• First published in 1957 as an ASRE
standard
• Main components:
―Numbering & Designation of Refrigerants
―Safety Group Classifications
―Refrigerant Concentration Limit
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4. Latest Technology in Refrigeration and Air Conditioning - XVII European Conference Milano, 9 - 10 June 2017
ASHRAE Standard 34 – Basis of Standard
©2014 Daikin Applied 4

5. Latest Technology in Refrigeration and Air Conditioning - XVII European Conference Milano, 9 - 10 June 2017
What is ASHRAE Standard 15?
• ASHRAE Standard 15 is directed
toward the safety of persons and
property on or near the premises
where refrigeration facilities are
located.
• The first Safety Code for
Mechanical Refrigeration,
recognized as American Standard
B9 in October 1930, appeared in
the first edition, 1932–1933, of
the ASRE Refrigerating Handbook
and Catalog.
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6. Latest Technology in Refrigeration and Air Conditioning - XVII European Conference Milano, 9 - 10 June 2017
ASHRAE Standard 15 – Basis of Standard
Restrictions on Refrigerant Use
• concept of Refrigerant Concentration Limit (RCL)
• RCL established based on the worst case of:
― flammability risk (with factor of safety, ≤25% of LFL)
― acute toxicity risk (worst case of: ① mortality, ② cardiac
sensitization, ③ anesthetic or central nervous system effects, and ④
other escape impairing effects and permanent injury)
― asphyxiation risk (oxygen deprivation limit)
• Underlying assumption within Standard 15 is that the total
refrigerant charge (per refrigerant circuit) is completely discharged
and uniformly mixes within the volume of the occupied space under
consideration
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Standards Update Process
• Standard 15 & 34 are both “Continuous
Maintenance”
• Anyone can submit change proposals at
any time, ASHRAE SSPC committee
reviews and can modify, accept, or reject
• Consensus-based development with a
public review process
• Addenda published on continuous basis
• Every 3 years publish an updated edition,
including all addenda approved since the
prior edition
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8. Latest Technology in Refrigeration and Air Conditioning - XVII European Conference Milano, 9 - 10 June 2017
Low-GWP Alternative Refrigerants Research
• Viable low GWP alternatives exist
• Many promising refrigerants are classified
2L under ASHRAE 34 (mildly flammable)
• ASHRAE 15 does not currently differentiate
between class 2 and 2L refrigerants
• IEC 60335-2-40 does not currently have
requirements for 2L refrigerants

9. Latest Technology in Refrigeration and Air Conditioning - XVII European Conference Milano, 9 - 10 June 2017
Refrigerant Selection Criteria

10. Latest Technology in Refrigeration and Air Conditioning - XVII European Conference Milano, 9 - 10 June 2017
Flammable Refrigerant Research
• Joint effort by, ASHRAE, AHRTI and U.S. Dept
of Energy
• The objective is to
– produce publicly available technical results
to support code and standard activities
related to the use of flammable refrigerants.
• Ensure a timely completion of relevant
standard revision.
Summer
2017:
draft
ASHRAE 15
completed
for PPR
End of 2017:
publication of the
updated ASHRAE
15 including 2L
refrigerants
Jan 2018:
2021 IMC: change
proposals are due
AHRTI/ASHRAE/
DOE Research
to support
ASHRAE 15
revisions

11. Latest Technology in Refrigeration and Air Conditioning - XVII European Conference Milano, 9 - 10 June 2017
Funding for Top Priority Research Projects on
Flammable Refrigerants
• 7 top priority projects have been identified
• Funding commitments are in from:
– U.S. DOE -- $3 million
– ASHRAE -- $1.2 million
– AHRTI -- $1 million

12. Latest Technology in Refrigeration and Air Conditioning - XVII European Conference Milano, 9 - 10 June 2017
Flammable Refrigerant Research
• ASHRAE-RP 1806: Flammable Refrigerants Post-ignition Risk Assessment
• Cost: $800,000, Duration 12 months
– Objectives:
• Understand the severity of events where flammable refrigerants are
being ignited.
• Assess the overall risks of using flammable refrigerants taking into
account both event probability and severity.
– Findings will:
• Aide in the proper design and the associated fire mitigation and
detection methods.
• Update existing risk assessments by adding the event severity to the
overall risk (probability x severity)
• Help further refine the accuracy of Safety Standards currently being
developed for flammable refrigerants and the associated Building
Codes.

13. Latest Technology in Refrigeration and Air Conditioning - XVII European Conference Milano, 9 - 10 June 2017
• ASHRAE-RP 1808: Servicing and Installing Equipment using
Flammable Refrigerants-Assessment of Field-made Mechanical
Joints
• Cost:$80,000, Duration: 6 months
– Objective:
• Assess effectiveness of joints made in the field, taking into
account human and mechanical factors.
– Findings will
• Help determine whether common types of joints other than
brazed or soldered joints should or should not be allowed in
the ASHRAE Standard 15.2 and relevant codes and
standards.
Flammable Refrigerant Research

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Flammable Refrigerant Research
• ASHRAE-RP 1807: Guidelines for flammable refrigerant
handling, and equipment servicing and installation
• Cost: $80,000, Duration: 6 months
– Objectives:
• Review existing requirements/practice for safe handling of
flammable refrigerants
• Review technician licensing or certification requirements
• Propose requirements for servicing and installing HVACR products
using flammable refrigerants
– Findings will support revisions of relevant sections in
ASHRAE and UL safety standards.

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Flammable Refrigerant Research
• AHRTI 9007: Benchmarking Risk by Real Life Leaks and Ignitions Testing
• Cost: $600,000, Duration : 9 months
– Objectives:
• Conduct A2L refrigerant leak and ignition testing under realistic
conditions
• Understand the risk relative to the A1 refrigerants while considering
ambient conditions and refrigerant lubricants.
– Findings will:
• Provide input to the next ASHRAE 15 code cycle and follow-on
revisions to building codes
• Benchmark/validate risk
• Determine the type of (or need for) hazard mitigation strategies

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Flammable Refrigerant Research
• AHRTI 9008: Investigation of Hot surface Ignition Temperature
(HSIT) for A2L Refrigerants
• Cost: $100,000, Duration: 6 months
– Objectives:
• Establish a standard HSIT test method
• Conduct the HSIT testing at various ambient conditions
with oil and air velocity effects included
– Findings will:
• Determine/define appropriate HSIT limits for
appropriate HVACR equipment and safety standards.

17. Latest Technology in Refrigeration and Air Conditioning - XVII European Conference Milano, 9 - 10 June 2017
Flammable Refrigerant Research
• AHRTI 9009: Leak Detection of A2L Refrigerants in HVACR
Equipment
• Cost: $50,000, Duration: 6 months
– Objective:
• Assess sensor technologies that can be used to detect A2L
refrigerants and easily integrated into HVACR equipment
– Main tasks are:
• Review existing and new sensor technologies
• Identify key known failure modes
• Propose a suitable reliability testing program/procedure to
address the potential failure modes

18. Latest Technology in Refrigeration and Air Conditioning - XVII European Conference Milano, 9 - 10 June 2017
Flammable Refrigerant Research
• DOE/ORNL: Determination of setting charge limits for various types of equipment
employing Flammable Refrigerants
• Cost: $1,000,000, Duration: 12 months
– Objectives:
• Determine the effectiveness to mitigate the risk of current m1/m2/m3
refrigerant charge limits in the IEC 60335-2-40 Annex GG
– Main tasks:
• Evaluate existing CFD results effectiveness for setting the charge limit and
mitigation requirements
• Identify gaps and develop CFD matrix to account for:
– Equipment
– room layout
– leak scenarios (rates and location)
– mitigation strategies
• Conduct CFD simulations

19. Latest Technology in Refrigeration and Air Conditioning - XVII European Conference Milano, 9 - 10 June 2017
Thank you!