This is a legacy version of the WELL Building Standard. Please check the latest version here.

Outdoor air systems

Dedicated outdoor air systems remove the constraints associated with linking heating and cooling with ventilation, so that optimal air quality and thermal comfort can be independently achieved.

Although there is evidence that thermal comfort and space conditions may improve through the use of dedicated outdoor air systems (DOAS), ASHRAE does not currently have a separate published and peer-reviewed standard or design guide for them. A properly designed DOAS can save energy compared to conventional systems while always supplying the appropriate amount of ventilation. This feature sets requirements for projects implementing DOAS systems.

Part 1: Dedicated Outdoor Air Systems

Dedicated outdoor air systems are used for heating and/or cooling systems and verified as being adequate through one of the following:

a. The system complies with local codes or standards regarding dedicated outdoor air systems.
b. A detailed design review of the proposed system is conducted by an independent, qualified and registered professional mechanical engineer (not employed or compensated by the mechanical engineer on record). The review addresses thermal comfort (temperature, humidity, air velocity, etc.) and ventilation rates, as well as overall serviceability and system reliability. Report must demonstrate satisfactory compliance with all applicable ASHRAE standards and codes.
Respiratory

Applicability Matrix

Core & Shell New & Existing Buildings New & Existing Interiors
Part 1: Dedicated Outdoor Air Systems O O O
Commercial Kitchen Education Multifamily Residential Restaurant Retail
Part 1: Dedicated Outdoor Air Systems O O O O O

Verification Methods Matrix

Letters of Assurance Annotated Documents On-Site Checks
Part 1: Dedicated Outdoor Air Systems MEP