Codes & Standards

April 1, 2007
ASHRAE The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) recently announced that five proposed addenda to ANSI/ASHRAE/IESNA


The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) recently announced that five proposed addenda to ANSI/ASHRAE/IESNA Standard 90.1-2007, Energy Standard for Buildings Except Low-Rise Residential Buildings, are open for public review.

Open for public review until April 15 are:

  • Addendum a, which clarifies that the standard applies to open-circuit cooling towers only.

  • Addendum b, which, for minimum ventilation requirements, references ANSI/ASHRAE Standard 62.1-2004, Ventilation for Acceptable Indoor Air Quality, rather than a specific section of the standard, and provides an exception allowing a regulating body to require more-stringent ventilation rates.

  • Addendum c, which adds vivaria to the list of spaces requiring specific humidity levels to satisfy the process needs in Section

Open for public review until April 30 are:

  • Addendum d, which allows the use of high-solar-heat-gain-coefficient plastic skylights in climate zones 1 through 3 when high-diffusion skylights are used in conjunction with a multilevel photocontrol system.

  • Addendum e, which expands energy-recovery requirements to cover use by weather zone and for outside-air percentages equal to or greater than 30 percent.

In other news, ASHRAE recently announced that five proposed addenda to Standard 62.1-2007 are open for public review until April 30:

  • Addendum a, which addresses compliance issues that may result from unclear wording or phrasing in Section 5.

  • Addendum b, which clarifies informative language in appendices C, D, and F.

  • Addendum c, which adds air-cleaning requirements to Section 6. If the addendum is approved, intake air filters with a minimum efficiency reporting value of 11 would be needed for particulate matter 2.5 microns in diameter in non-attainment areas. Additionally, ozone air cleaners with at least 40-percent efficiency would be needed for systems in non-attainment areas designated by the U.S. Environmental Protection Agency as “serious,” “severe,” or “extreme.”

  • Addendum d, which adds occupancy categories to Table 6-1.

  • Addendum i, which requires that zones with environmental tobacco smoke (ETS) be supplied with more outdoor air than ETS-free areas of the same occupancy category. Outdoor airflow rate would be determined using “engineered methods with the approval of the authority having jurisdiction.”

To read and comment on any of the addenda above, visit during the public-review period.

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.