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  • Writer's pictureTom Petersen

ASHRAE Standard 62: Ventilation for Acceptable Indoor Air Quality

Updated: Aug 28, 2023

American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) Standard 62 specifies levels for ventilation rates and other indoor air quality parameters, such as formaldehyde, lead, and carbon monoxide. The Standard provides procedures for achieving acceptable indoor air quality. All updated Standards revise 62-1989 while keeping consistent with its scope and philosophy. None of the changes impact the design procedures contained in the Standard.

See the revisions found in each publication below.

ASHRAE 62-1999

ASHRAE 62-2001

ASHRAE 62.2-2003

The following revisions can be found in ASHRAE 62-1999 – Ventilation for Acceptable Indoor Air Quality:

  • Removal of the consideration of thermal comfort from the standard.

  • Addition of a disclaimer that says compliance with the standard will not necessarily result in acceptable indoor air quality because there are different circumstances for different occupants and the comfort and health effects of indoor environments are very complex and not fully understood.

  • Removal of the statement that recommended ventilation rates are intended to accommodate a moderate amount of smoking. The standard does not attempt to prohibit smoking or any other activity in buildings.

  • Clarification of the significance of indoor carbon dioxide levels. The standard now stresses that carbon dioxide is simply a useful indicator of the concentration of human bioeffluents, rather than a comprehensive indicator of indoor air quality

The following revisions can be found in ASHRAE 62-2001 – Ventilation for Acceptable Indoor Air Quality:

  • Addition of prescriptive requirement for natural ventilation systems and of performance criteria for surface materials in ventilation equipment and ducts.

  • Creation of new sections on construction and ventilation system startup requirements and on operation and maintenance procedures.

  • Modified requirements for providing combustions air for fuel-burning appliances

  • Clarification and removal of several definitions.

  • Updated particle filtration requirements.

The following revisions can be found in ASHRAE 62.2-2003 – Ventilation and Acceptable Indoor Air Quality in Low-Rise Buildings:

  • Clarification of the description of the Ventilation Rate Procedure and of condensate management and control of contaminants from some local sources.

  • Clarification of the standard’s relevance to new and existing buildings and its coverage of industrial and laboratory spaces and of several definitions

  • Addition of an informative appendix addressing the application of the standard in new and existing buildings and a caveat concerning situations where outdoor air quality may be poor

  • Creation of new sections on determining design ventilation rates in smoking permitted areas, on indoor humidity and the building envelope requirements, and on monitoring of air-distribution systems in occupied spaces.

  • Modification of outdoor air quality assessment and air intake filtration requirements

  • Updated contaminant concentration guidelines and intake air cleaning requirements when outdoor ozone levels are elevated.

For more information about the ASHRAE Standard 62, check out

This page was previously known as ASHRAE Standard 62-1999

EES can help you meet the recommendations of ASHRAE Standard 62 and EPAINIOSH Guidelines. We provide IAQ and ventilation services for industrial and commercial facilities.



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