ASHRAE 62.1 Standard for ventilation for indoor air quality

ANSI/ASHRAE Standard 62.1-2019 – Ventilation for Acceptable Indoor Air Quality

ASHRAE Standard for ventilation for indoor air quality

ASHRAE Standard for ventilation for indoor air quality

The ANSI/ASHRAE 62.1 – 2022 standard is intended for regulatory application to new buildings, additions to existing buildings, and changes to existing buildings. It can also guide the improvement of IAQ in existing buildings.

ANSI/ASHRAE 62.1-2022 covers ventilation and air-cleaning system design, installation, commissioning, and operation and maintenance. Beyond ventilation, the standard possesses information pertinent to certain contaminants and contaminant sources—outdoor air, construction processes, moisture, and biological growth.

It includes three procedures for ventilation design: the IAQ Procedure, the Ventilation Rate Procedure, and the Natural Ventilation Procedure.

ANSI/ASHRAE 62.1-2022 applies to spaces intended for human occupancy within buildings. However, this does not include “those within dwelling units in residential spaces in which occupants are non-transient.”

New in the 2022 edition of the standard are changes that represent years of research, statistical evidence, and improved building systems and technologies:

  • Reorganized Section 5, “Systems and Equipment,” to better reflect the path of airflow. It also illustrates how buildings, systems, and equipment are related.
  • Continued focus on IAQ, including improvements to the IAQ Procedure, setting maximum dew-point temperatures in mechanically cooled buildings and required exhaust air separation distances.
  • Relocated health-care-related spaces in the scope of ASHRAE/ASHE Standard 170 to a new normative appendix.
  • Updated definitions, clarified air density adjustments, and removal of items related to transient occupancies that now fall under Standard 62.2
  • New title that reflects how indoor air quality (IAQ) goes beyond minimum ventilation requirements.
  • IAQ Procedure:

    IAQP allows ventilation air to be reduced below rates that would have been required by the VRP if it can be reliably demonstrated that the resulting air quality meets the required criteria. This helps reduce the overall energy usage intensity (EUI) of the project while maintaining indoor air quality.

  • Ventilation Rate Procedure:

    The procedure prescribes the quantity of outdoor air required to deliver to each zone. Intended use of zonae area decides quantity of air. It prescribes how to calculate the outdoor airflow needed at the system-level inlet.

  • Natural Ventilation Procedure:

    It provides rule-of-thumb design parameters for naturally ventilated spaces. This act as guidelines to designers to a basic approach, which is suitable for most non-complex single or double-sided natural ventilation schemes.