• ASHRAE Updates Refrigerant Safety Standards

    Oct. 15, 2010
    The updated ASHRAE Refrigerant safety standards publication includes 14 new blends.

    The 2010 editions of ASHRAE’s major refrigerants-related standards have been published as a package. It includes the addition of 14 new refrigerant blends.

    Requirements in ANSI/ASHRAE Standard 34-2010, Designation and Safety Classification of Refrigerants, and ANSI/ASHRAE Standard 15-2010, Safety Standard for Refrigeration System, complement each other, in that Standard 34 describes a shorthand way of naming refrigerants and assigns safety classifications based on toxicity and flammability data; Standard 15 establishes procedures for operating equipment and systems when using those refrigerants. ASHRAE sells the standards as a set.

    Standard 34-2010 combines the 2007 standard and 37 published addenda. Among the key changes incorporated into the 2010 edition are:

    • assignment of designations and safety classifications for one new single compound refrigerant and 14 new refrigerant blends
    • addition of occupational exposure limits for refrigerants to Tables 1 and 2
    • addition of new data and updates of refrigerant concentration limits (RCL) and safety classifications for several existing refrigerants
    • addition of an optional 2L subclass to the existing Class 2 flammability classification, which signifies Class 2 refrigerants with a burning velocity less than or equal to 10 cm/s.
    • introduction of a modified method of calculating the heat of combustion for refrigerants along with inclusion of an illustrative example of the calculation
    • addition of an informative appendix showing an example of the calculation of the acute toxicity exposure limit and refrigerant concentration limit for a refrigerant blend

    Changes to Standard 15 include incorporation of nine new addenda. The changes made through these addenda include:

    • a revision of requirements for terminating relief vent discharge lines
    • revision to bring the standard into alignment with UL 984 (Hermetic Refrigerant-Motor Compressors)
    • addition of definitions so the standard can better provide for the safety of cascade refrigeration systems
    • a revision to provide appropriate guidance for the protection of positive displacement compressors when used in cascade refrigeration system configurations
    • a revision to bring the standard into alignment with Standard 34, by removing Table 1 for “refrigerant quantity limits,” and uniformly using the term “refrigerant concentration limits.”

    Standard 15-2010 and Standard 34-2010 are sold together. The cost is $89 ($75 for ASHRAE members). To order, contact ASHRAE Customer Service at 800/527-4723 or visit ashrae.org/bookstore.