scope:

In the 2016 standard ". . . three stories or fewer above grade. . ." was deleted, changing the scope of the standard to include dwelling units in multifamily buildings of any height. Standard 62.1-2016 addresses spaces other than dwelling units in residential occupancies in multifamily buildings, such as corridors, mechanical rooms, and garages.

§2.3. Section 2.3 was deleted in the 2016 Standard, which stated "This standard does not address unvented combustion space heaters." As determined appropriate, provisions addressing unvented combustion space heaters will be considered in future editions.

Purpose

This section of the Standard describes why the Standard exists and what compliance with the standard is expected to achieve. For the 2016 standard, the words "low-rise" were deleted from the one-sentence purpose statement to reflect the expanded scope of the standard from residential buildings of three or fewer stories above grade to the dwelling units in buildings of any height.

The Purpose of the standard has two parts. The first part states "This standard defines the roles of and minimum requirements for mechanical and natural ventilation systems and the building envelope…." This describes the parts of the building that the provisions of the standard address: the ventilation system (mechanical and natural) and the building envelope (air leakage).

The second part of the Purpose states the standard is ". . . intended to provide acceptable indoor air quality (IAQ) in residential buildings." This short statement describes the purpose of the provisions of the standard. Acceptable indoor air quality is a term defined in §3, Definitions, to mean air that is neither irritating nor unhealthy. Indoor air that is not acceptable is air that smells bad; contains irritating contaminants, such as pollen or other allergens; or contains contaminants at concentrations that might have harmful health effects. Unacceptable indoor air can have one, two, or all three of these characteristics. It might have odors only, but not be unhealthy, or it might be air that seems healthy, but contains dangerous concentrations of toxic chemicals that cannot be sensed by the occupants.

In summary, the Purpose states that the standard prescribes mechanical ventilation, building envelope recommendations, and other measures intended to provide residential indoor air quality that is acceptable for human health and comfort.