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

Ventilation effectiveness

Routine indoor activities including cooking, cleaning, building operations and maintenance and even the presence of occupants themselves can degrade air quality. Many indoor pollutants resulting from such activities, including particulate matter and VOCs can cause discomfort and trigger asthma and eye, nose and throat irritation. Because it is difficult to test for every potential pollutant, and because carbon dioxide is easy to detect, carbon dioxide levels serve as a proxy for other indoor pollutants.

This feature sets a foundation for ventilation rates, which can be adjusted according to measured concentrations of carbon dioxide. It is based on ASHRAE requirements for adequate ventilation, which include separate options for mechanically ventilated and naturally ventilated buildings. The requirements in this feature—and other ventilation-related features—follow that same division.

Part 1: Ventilation Design

One of the following requirements is met for all spaces:

a.6 Ventilation rates comply with all requirements set in ASHRAE 62.1-2013 (Ventilation Rate Procedure or IAQ Procedure).
b.6 Projects comply with all requirements set in any procedure in ASHRAE 62.1-2013 (including the Natural Ventilation Procedure) and demonstrate that ambient air quality withi 1.6 km [1 mi] of the building is compliant with either the U.S. EPA's NAAQS or passes the Air Quality Standards in the WELL Building Standard for at least 95% of all hours in the previous year.
Part 2: Demand Controlled Ventilation

For all spaces with an actual or expected occupant density greater than 25 people per 93 m² [1,000 ft²], one of the following requirements is met:

a.7 A demand controlled ventilation system regulates the ventilation rate of outdoor air to keep carbon dioxide levels in the space below 800 ppm.
b.7 Projects that have met the Operable windows feature demonstrate that natural ventilation is sufficient to keep carbon dioxide levels below 800 ppm at intended occupancies.
Part 3: System Balancing

After the HVAC system is installed, the following requirement is met:

a. After substantial completion and prior to occupancy, the HVAC system undergoes testing and balancing.
Part 4: Ventilation Rates for Residences

Depending on ventilation methods, one of the following is met:

a.117 Ventilation rates are designed to comply with all requirements set in ASHRAE 62.2-2013 (Ventilation Rate Procedure or IAQ Procedure) for residential buildings of 3 or fewer floors.
b.6 Ventilation rates are designed to comply with all requirements set in ASHRAE 62.1-2013 (Ventilation Rate Procedure or IAQ Procedure) for residential buildings of more than 3 floors above grade.
Respiratory
Cardiovascular
Nervous

Applicability Matrix

Core & Shell New & Existing Buildings New & Existing Interiors
Part 1: Ventilation Design P P P
Part 2: Demand Controlled Ventilation P P P
Part 3: System Balancing - P P
Part 4: Ventilation Rates for Residences - - -
Commercial Kitchen Education Multifamily Residential Restaurant Retail
Part 1: Ventilation Design P P - P P
Part 2: Demand Controlled Ventilation P P - P -
Part 3: System Balancing P P - P P
Part 4: Ventilation Rates for Residences - - P - -

Verification Methods Matrix

Letters of Assurance Annotated Documents On-Site Checks
Part 1: Ventilation Design MEP
Part 2: Demand Controlled Ventilation MEP
Part 3: System Balancing Commissioning Report
Part 4: Ventilation Rates for Residences MEP
6

ASHRAE Standing Standard Project Committee 62.1. ANSI/ASHRAE STANDARD 62.1-2013: Ventilation for Acceptable Indoor Air Quality. Atlanta: ASHRAE; 2013.

03.1.a

ASHRAE's Standard 62.1: Ventilation for Acceptable Indoor Air Quality provides guidelines for ventilation rates.

03.1.b

ASHRAE's Standard 62.1: Ventilation for Acceptable Indoor Air Quality provides ventilation rates.

03.4.b

ASHRAE's Standard 62.1: Ventilation for Acceptable Indoor Air Quality provides guidelines for ventilation rates.

7

Illinois Department of Public Health. Illinois Department of Public Health Guidelines for Indoor Air Quality. http://www.idph.state.il.us/envhealth/factsheets/indoorairqualityguide_fs.htm. Updated May 2011. Accessed September 15, 2014.

03.2.a

The IDPH's Guidelines for Indoor Air Quality recommend properly ventilated buildings should have carbon dioxide levels with a floor or building average of 800 ppm or less.

03.2.b

The IDPH's Guidelines for Indoor Air Quality recommend properly ventilated buildings should have carbon dioxide levels with a floor or building average of 800 ppm or less.

117

ASHRAE Standing Standard Project Committee 62.2. ANSI/ASHRAE STANDARD 62.2-2013: Ventilation for Acceptable Indoor Air Quality in Low-Rise Residential Buildings. Atlanta: ASHRAE; 2013.

03.4.a

ASHRAE's Standard 62.2 provides guidelines for ventilation rates for single family homes and low-rise multifamily units of three or fewer floors.