ASHRAE Insights

Revisions to ASHRAE’s Standard 34 should make it easier for manufacturers to prepare applications for refrigerant number assignment and safety classification.

ANSI/ASHRAE Standard 34-2007, Designation and Safety Classification of Refrigerants, establishes a simple means of referring to common refrigerants in place of chemical names, formulas or trade names. It also establishes safety classifications based on toxicity and flammability data. The 2007 standard contains a total of 16 new refrigerants.

The new standard contains revisions to the flammability classification and details on the flammability and fractionation testing procedures. These are intended to make it easier for manufacturers to prepare applications for refrigerant number assignment and safety classification, according to Bill Walter, Standard 34 committee chair.

In addition, a new section has been added specifying the criteria to determine recommended refrigerant concentration limits (RCL) in occupied spaces. The addition of RCL values will be useful in application of the refrigerants in the field.

“In general, incorporating the 23 approved addenda into one document makes the standard easier to read and understand, making it easier for users to determine the current requirements to get a refrigerant listed in the standard,” said Walter.

The cost of Standard 34-2007 is $39 for ASHRAE members.

To order, contact ASHRAE Customer Service at 1-800-527-4723 (United States and Canada) or 404-636-8400 (worldwide), by mail at 1791 Tullie Circle NE, Atlanta, GA 30329, or visit www.ashrae.org/bookstore.