Dec. 1, 2010

The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) recently announced the publication of ANSI/ASHRAE Standard 55-2010, Thermal Environmental Conditions for Human Occupancy.

The standard specifies combinations of indoor thermal environmental factors and personal factors that produce conditions acceptable to a majority of the occupants of a space. The 2010 version combines Standard 55-2004 and 10 approved and published addenda, including:

  • Recent innovations, such as the use of elevated air speeds, to widen the acceptable range of thermal conditions.

  • A new method of determining the cooling effect of air movement above 30 fpm. This allows ceiling fans and other means of elevating air speed to provide comfort at temperatures higher than those permissible previously.

  • Clearer minimum requirements for showing a design meets the standard. Additionally, a form for documenting compliance is provided in an informative appendix.

  • Improved and expanded graphics.

The cost of Standard 55-2010 is $59 for ASHRAE members and $69 for non-members. To order, contact ASHRAE Customer Service by phone at 1-800-527-4723 (United States and Canada) or 404-636-8400 or by fax at 404-321-5478, or visit

In other news, ASHRAE announced the International Code Council's (ICC's) approval of several recent ASHRAE proposals.

The 2012 International Mechanical Code, due in April 2011, will incorporate requirements from ANSI/ASHRAE/ACCA Standard 180-2008, Standard Practice for Inspection and Maintenance of Commercial Building HVAC Systems.

“Inclusion of Standard 180 in code documents is an important advance,” Robert Baker, chair of the Standard 180 committee, said. “Proper maintenance is critical to preserving an HVAC system's ability to continue to realize the energy-efficiency capabilities that are designed into today's systems. If we are to realize the vital energy-independence goals that we have established, excellence in maintenance will be an important part of the package of things we must achieve.”

John Sedine, chairman of the Air Conditioning Contractors of America's (ACCA's) board of directors, called the ICC's approval “an important step toward safer and more efficient commercial buildings.”

Also approved were changes regarding energy stringency based on requirements in ANSI/ASHRAE/IES Standard 90.1-2010, Energy Standard for Buildings Except Low-Rise Residential Buildings, including:

  • The addition of requirements for areas under skylights.

  • The modification of efficiency requirements for heat-rejection and heat-transfer equipment.

  • The modification of piping-insulation requirements.

Also approved was a proposal rewriting the majority of the commercial chapter of the International Energy Conservation Code. The proposal maintains the reference to the prescriptive requirements of Standard 90.1 and makes the following consistent with the 2010 version of Standard 90.1: fenestration leakage, demand controlled ventilation, energy recovery, economizer efficiency, lighting controls, lighting-system functional testing, and space-lighting power densities. Also, the proposal calls for an additional path of compliance for water-cooled chillers.

About the Author

Scott Arnold | Executive Editor

Described by a colleague as "a cyborg ... requir(ing) virtually no sleep, no time off, and bland nourishment that can be consumed while at his desk" who was sent "back from the future not to terminate anyone, but with the prime directive 'to edit dry technical copy' in order to save the world at a later date," Scott Arnold joined the editorial staff of HPAC Engineering in 1999. Prior to that, he worked as an editor for daily newspapers and a specialty-publications company. He has a bachelor's degree in journalism from Kent State University.