ASTM D7326-21

Standard Practice for Handling, Transportation, and Storage of HFC Blend B (CH<inf >2</inf>FCF<inf>3</inf>, CHF<inf>2</inf>CF<inf>3</inf>, and CO<inf >2</inf>)

SIGNIFICANCE AND USE
4.1 This practice provides requirements for the handling, transportation, and storage of HFC Blend B encountered in distribution through both commercial and military channels. It is intended to ensure that HFC Blend B is handled, transported, and stored in such a way that its physical property virtues are not degraded. Transport may be by various means, such as, but not limited to, highway, rail, water, and air.
SCOPE
1.1 This practice covers guidance and direction to suppliers, reclaimers, purchasers, and users in the handling, transportation, and storage of HFC Blend B.  
1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.  
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 31-May-2021
• ICS: 71.080.20 - Halogenated hydrocarbons
• Technical Committee: D26 - Halogenated Organic Solvents and Fire Extinguishing Agents
• Drafting Committee: D26.09 - Fire Extinguishing Agents

Relations

• Refers: ASTM D7327-12 - Standard Specification for HFC Blend B (CH₂FCF₃, CHF₂CF₃, and CO₂)
• Effective Date: 01-Sep-2012
• Refers: ASTM D7327-07 - Standard Specification for HFC Blend B (CH₂FCF₃, CHF₂CF₃, and CO₂)
• Effective Date: 01-Apr-2007

Overview

ASTM D7326-21 is the internationally recognized standard practice issued by ASTM International for the proper handling, transportation, and storage of HFC Blend B. HFC Blend B is a tertiary blend composed of HFC-134a (1,1,1,2-tetrafluoroethane), HFC-125 (pentafluoroethane), and carbon dioxide (CO₂). The blend is widely utilized as a fire suppressant and explosion hazard mitigation agent in both commercial and military applications.

This standard offers comprehensive requirements and practical guidance to suppliers, reclaimers, purchasers, and end-users for ensuring that the integrity of HFC Blend B is maintained throughout its lifecycle. The procedures outlined in ASTM D7326-21 are designed to prevent product degradation and preserve its essential properties during distribution and storage.

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Key Topics

• Personnel Training
  Personnel involved in handling HFC Blend B must be properly trained in relevant compressed gas safety standards (such as those by the Compressed Gas Association) and comply with U.S. Department of Transportation (DOT) regulations.

• Handling Practices
  Safe handling includes using well-ventilated, nonsmoking facilities, preventing contamination, and adhering to maximum filling densities as specified in regulatory guidelines.

• Transportation Requirements
  Transportation of HFC Blend B must comply with DOT 49 CFR regulations, including the use of approved containers, proper labeling, and securing cylinders to avoid mechanical or thermal damage.

• Storage Guidelines
  Storage requires protection from physical and environmental hazards, routine inspection, appropriate safety relief devices, and segregation of conforming vs. non-conforming product as per Specification D7327.

• Inspection and Marking
  Cylinders are to undergo periodic hydrostatic testing and must be clearly marked with product identification, conforming status, and supplier information according to DOT and ASTM requirements.

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Applications

HFC Blend B covered under ASTM D7326-21 is applied extensively in:

• Fire Suppression Systems:
  Used in portable and fixed fire extinguishing equipment for critical infrastructure, defense applications, and commercial facilities.

• Explosion Protection:
  Ideal for environments at risk of explosion, including chemical plants, data centers, and transportation hubs.

• Reclamation and Recycling:
  The standard facilitates proper procedures for the safe and environmentally responsible recovery, recycling, and reissue of reclaimed HFC Blend B.

• Military and Industrial Distribution:
  Ensures that product distributed via rail, road, air, or marine channels maintains its safety and efficacy.

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Related Standards

For comprehensive compliance and best practices, ASTM D7326-21 references several key standards, including:

• ASTM D7327 - Specification for HFC Blend B composition and quality.
• CGA C-1, C-6, C-7, P-1, SB-1, SB-18 - Compressed Gas Association standards for pressure testing, inspection, labeling, and safe handling of compressed gases.
• U.S. DOT 49 CFR Parts 172, 173, 178, 180 - U.S. Department of Transportation regulations on hazardous materials classification, packaging, labeling, and cylinder maintenance.
• WTO TBT Committee Principles - Underpinning international standardization principles for global trade and regulatory compliance.

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Adopting ASTM D7326-21 ensures that all stakeholders involved in the supply chain-from manufacturers and distributors to end-users-manage HFC Blend B safely, efficiently, and in accordance with applicable international regulations and industry best practices. Proper implementation limits risks, maintains product value, and supports environmental, health, and safety objectives.

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: D7326 − 21
Standard Practice for
Handling, Transportation, and Storage of HFC Blend B
(CH FCF , CHF CF , and CO )
2 3 2 3 2
This standard is issued under the fixed designation D7326; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope C-7 Guide to Classification and Labeling of Compressed
Gases
1.1 This practice covers guidance and direction to suppliers,
P-1 Standard for Safe Handling of Compressed Gases in
reclaimers, purchasers, and users in the handling,
Containers
transportation, and storage of HFC Blend B.
2.3 U.S. Government Standards:
1.2 The values stated in inch-pound units are to be regarded
49 CFR Part 172 Hazardous Materials Table, Special
as standard. The values given in parentheses are mathematical
Provisions, Hazardous Materials Communications, Emer-
conversions to SI units that are provided for information only
gency Response Information, Training Requirements, and
and are not considered standard.
Security Plans
1.3 This standard does not purport to address all of the 49 CFR Part 172.101 Purpose and Use of Hazardous Mate-
safety concerns, if any, associated with its use. It is the
rials Table
responsibility of the user of this standard to establish appro- 49 CFR Part 173 Shippers—General Requirements for Ship-
priate safety, health, and environmental practices and deter-
ments and Packagings
mine the applicability of regulatory limitations prior to use. 49 CFR Part 178 Specifications for Packagings
1.4 This international standard was developed in accor-
49 CFR Part 180 Continuing Qualification and Maintenance
dance with internationally recognized principles on standard- of Packagings
ization established in the Decision on Principles for the
3. Terminology
Development of International Standards, Guides and Recom-
mendations issued by the World Trade Organization Technical
3.1 Definitions of Terms Specific to This Standard:
Barriers to Trade (TBT) Committee.
3.1.1 containers, n—storage vessels for HFC Blend B.
3.1.2 cylinders, n—containers of HFC Blend B.
2. Referenced Documents
2 3.1.3 HFC Blend B, n—tertiary blend comprised of HFC-
2.1 ASTM Standard:
134a (1,1,1,2-tetrafluoroethane), HFC-125
D7327 Specification for HFC Blend B (CH FCF ,
2 3
(pentafluoroethane), and carbon dioxide (CO ); a compound
CHF CF , and CO )
2 3 2
3 used to inert, extinguish, or suppress a fire or explosion hazard.
2.2 CGA Standards:
3.1.4 insulated, adj—placed in an isolated situation to pro-
C-1 Methods for Pressure Testing Compressed Gas Cylin-
tect and prevent the transfer of damage.
ders
C-6 Standards for Visual Inspection of Steel Compressed
4. Significance and Use
Gas Cylinders
4.1 This practice provides requirements for the handling,
transportation, and storage of HFC Blend B encountered in
This practice is under the jurisdiction of ASTM Committee D26 on Haloge-
distribution through both commercial and military channels. It
nated Organic Solvents and Fire Extinguishing Agents and is the direct responsi-
bility of Subcommittee D26.09 on Fire Extinguishing Agents. is intended to ensure that HFC Blend B is handled, transported,
Current edition approved June 1, 2021. Published June 2021. Originally
and stored in such a way that its physical property virtues are
approved in 2006. Last previous edition approved in 2017 as D7326-17. DOI:
not degraded. Transport may be by various means, such as, but
10.1520/D7326-21.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or not limited to, highway, rail, water, and air.
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. Code of Federal Regulations (CFR) documents are available from U.S.
Available from Compressed GasAssociation (CGA), 8484 Westpark Dr., Suite Government Publishing Office (GPO), 732 N. Capitol Street, NW, Washington, DC
220, McLean, VA 22102, http://www.cganet.com. 20401, http://www.gpo.gov.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D7326 − 21
3 3
5. Practice B shall be 58 lb/ft (930 kg/m ). Filling density requirements
arespecifiedin49CFRPart173.304and49CFRPart173.305.
5.1 To ensure safe handling, loading, unloading, storing,
5.2.5 Handling of materials should be done in a manner that
and transporting of material, personnel shall be trained in the
CGApublications and 49 CFR regulations as listed in Sections prevents contamination or comingling of materials other than
2.2 and 2.3, respectively.
HFC Blend B.
5.2 Handling:
5.3 Transportation:
5.2.1 Handling shall be in accordance with CGA Publica-
5.3.1 Transportationshallbeasspecifiedinaccordancewith
tion P-1.
Department of Transportation (DOT) regulations of 49 CFR.
5.2.1.1 Personnel who handle or store, or both, cylinders of
5.3.1.1 Shipment of materials between collectors, recyclers,
HFC Blend B shall be trained properly to recognize and
and reclaimers should be within approved DOT guidelines for
identify the characteristics of the product and the proper
Class 2, Division 2.2, regulated materials. Any further provi-
methods of safely handling full, partially full, and empty
sions for special transportation or packaging should be agreed
cylinders.
5.2.2 All HFC Blend B transfers between storage containers upon between the collectors, recyclers, and reclaimers.
and recycling processes shall be performed by personnel
5.3.1.2 The minimum design pressure requirements shall be
trained in handling procedures.
as indicated in 49 CFR Part 173.304. The pressure inside the
5.2.2.1 HFC Blend B recycling and transfer processes shall
container at 70 °F (21 °C) shall not exceed the service pressure
be in conjunction with the equipment specified by the manu-
for which the container is marked. The pressure inside the
facturer.
container at 130 °F (54 °C) shall not exceed ⁄4 times the
5.2.3 To preclude product accumulation and decomposition,
service pressure
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: D7326 − 17 D7326 − 21
Standard Practice for
Handling, Transportation, and Storage of HFC Blend B
(CH FCF , CHF CF , and CO )
2 3 2 3 2
This standard is issued under the fixed designation D7326; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This practice covers guidance and direction to suppliers, reclaimers, purchasers, and users in the handling, transportation, and
storage of HFC Blend B.
1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical
conversions to SI units that are provided for information only and are not considered standard.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety safety, health, and healthenvironmental practices and determine the
applicability of regulatory limitations prior to use.
1.4 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standard:
D7327 Specification for HFC Blend B (CH FCF , CHF CF , and CO )
2 3 2 3 2
2.2 CGA Standards:
C-1 Methods for Pressure Testing Compressed Gas Cylinders
C-6 StandardStandards for Visual Inspection of Steel Compressed Gas Cylinders
C-7 Guide to Classification and Labeling of Compressed Gases
P-1 Standard for Safe Handling of Compressed Gases in Containers
SB-1 Safety Bulletin: Hazards of Refilling or Reusing Compressed Refrigerant (Halogenated Hydrocarbon) Gas Cylinders
SB-18 Safety Bulletin: Use of Refrigerant (Halogenated Hydrocarbons) Recovery Cylinders
2.3 U.S. Government Standards:
49 CFR Title 49, Part 172, U.S. Department of Transportation (DOT),Part 172 Hazardous Materials Table, Special Provisions,
Hazardous Materials Communications, Emergency Response Information, and Training RequirementsTraining Requirements,
and Security Plans
This practice is under the jurisdiction of ASTM Committee D26 on Halogenated Organic Solvents and Fire Extinguishing Agents and is the direct responsibility of
Subcommittee D26.09 on Fire Extinguishing Agents.
Current edition approved Feb. 1, 2017June 1, 2021. Published February 2017June 2021. Originally approved in 2006. Last previous edition approved in 20122017 as
D7326-12.-17. DOI: 10.1520/D7326-17.10.1520/D7326-21.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Available from Compressed Gas Association (CGA), 14501 George Carter Way, Suite 103, Chantilly, VA 20151,8484 Westpark Dr., Suite 220, McLean, VA 22102,
http://www.cganet.com.
Available Code of Federal Regulations (CFR) documents are available from U.S. Government Publishing Office (GPO), 732 N. Capitol Street, NW, Washington, DC
20401-0001,20401, http://www.gpo.gov.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D7326 − 21
49 CFR Title 49, Part 172.101, U.S. DOT,Part 172.101 Tables Purpose and Use of Hazardous Materials and Special
ProvisionsTable
49 CFR Title 49, Part 173, U.S. DOT,Part 173 Shippers-GeneralShippers—General Requirements for ShippingShipments and
Packagings
49 CFR Title 49, Part 178, U.S. DOT,Part 178 Specifications for Packagings
49 CFR Title 49, Part 180, U.S. DOT,Part 180 Continuing Qualification and Maintenance of Packagings
3. Terminology
3.1 Definitions of Terms Specific to This Standard:
3.1.1 containers—containers, n—storage vessels for HFC Blend B.
3.1.2 cylinders—cylinders, n—containers of HFC Blend B.
3.1.3 HFC Blend B—B, n—tertiary blend comprised of HFC-134a (1,1,1,2-tetrafluoroethane), HFC-125 (pentafluoroethane), and
carbon dioxide (CO ); a compound used to inert, extinguish, or suppress a fire or explosion hazard.
3.1.4 insulated—insulated, adj—placed in an isolated situation to protect and prevent the transfer of damage.
4. Significance and Use
4.1 This practice provides requirements for the handling, transportation, and storage of HFC Blend B encountered in distribution
through both commercial and military channels. It is intended to ensure that HFC Blend B is handled, transported, and stored in
such a way that its physical property virtues are not degraded. Transport may be by various means, such as, but not limited to,
highway, rail, water, and air.
D7326 − 21
5. Practice
5.1 To ensure safe handling, loading, unloading, storing, and transporting of material, personnel shall be trained in the CGA
publications and Title 49 CFR regulations as listed in Sections 2.2 and 2.3, respectively.
5.2 Handling:
5.2.1 Handling shall be in accordance with CGA P-1,Publication Safe Handling of Compressed Gases in Containers.P-1.
5.2.1.1 Personnel who handle or store, or both, cylinders of HFC Blend B shall be trained properly to recognize and identify the
characteristics of the product and the proper methods of safely handling full, partially full, and empty cylinders.
5.2.2 All HFC Blend B transfers between storage containers and recycling processes shall be performed by personnel trained in
handling procedures.
5.2.2.1 HFC Blend B recycling and transfer processes shall be in conjunction with the equipment specified by the manufacturer.
5.2.3 To preclude product accumulation and decomposition, HFC Blend B handling shall be performed in ventilated areas that are
nonsmoking and free of portable heaters. Provisions shall be made to ensure that service areas limit HFC Blend B concentrations
do not exceed 75 000 ppm (7.5 %) (7.5 %) by volume for 1 min and 100 ppm by volume for a time weighted time-weighted
exposure of 8 h.
5.2.4 Cylinders shall not be overfilled. The liquid portion of the HFC Blend B must not completely fill the container’scontainer’s
internal volume at any temperature up to and including 130 °F (54 °C). The maximum permitted filling density for HFC Blend B
3 3
shall be 58 lb/ft (930 kg/m ). Filling density requirements are specified in Title 49 CFR, CFR Part 173.304 and Title 49 CFR, CFR
Part 173.305.
5.2.5 Handling of materials should be done in a manner that prevents contamination or comminglingcomingling of halocarbons-
materials other than HFC Blend B.
5.2.6 Cylin
...