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  1. Air
  2. Air quality standards

Air quality standards

Features>Air>01. Air quality standards

01. Air quality standards

Pollutants generated indoors such as volatile organic compounds (VOCs), combustion byproducts and airborne particles are known to trigger nausea, asthma and allergies. While ambient outdoor air is often better quality, natural ventilation methods, operable windows and doors, and general envelope infiltration can harm indoor air quality if external air quality conditions are poor.

This feature requires that an accredited assessor complete a performance test after occupancy as an independent means of verifying that the building, whether naturally or mechanically ventilated, is meeting critical air quality requirements.

Part 1: Standards for Volatile Substances

The following conditions are met:

a) Formaldehyde levels less than 27 ppb.
b) Total volatile organic compounds less than 500 μg/m³.
Part 2: Standards for Particulate Matter and Inorganic Gases

The following conditions are met:

a) Carbon monoxide less than 9 ppm.
b) PM₂.₅ less than 15 μg/m³.
c) PM₁₀ less than 50 μg/m³.
d) Ozone less than 51 ppb.
e) Nitrogen dioxide less than 53 ppb.
Part 3: Below-Grade Air Quality Standards

The following conditions are met:

a) Radon less than 4 pCi/L in the lowest occupied level of the project.
Part 4: Operational Kitchen Air Quality

The following requirements are met in the commercial kitchen space:

a) Carbon monoxide levels less than 35 ppm.
b) PM₂.₅ less than 35 μg/m³.
c) Nitrogen dioxide less than 100 ppb.
Immune
Cardiovascular
Endocrine
Respiratory
Nervous

Applicability Matrix

Core & Shell New Construction WELL Interiors
Part 1: Standards for Volatile Substances P P P
Part 2: Standards for Particulate Matter and Inorganic Gases - P P
Part 3: Below-Grade Air Quality Standards P P P
Part 4: Operational Kitchen Air Quality - - -
Commercial Kitchen Education Multifamily Residential Retail
Part 1: Standards for Volatile Substances P P P P
Part 2: Standards for Particulate Matter and Inorganic Gases - P P P
Part 3: Below-Grade Air Quality Standards P P P P
Part 4: Operational Kitchen Air Quality P - - -

Verification Methods Matrix

Letters of Assurance Annotated Documents On-Site Checks
PART 1 (Performance)
Standards for Volatile Substances 		Performance Test
PART 2 (Performance)
Standards for Particulate Matter and Inorganic Gases 		Performance Test
PART 3 (Performance)
Below-Grade Air Quality Standards 		Performance Test
PART 4 (Performance)
Operational Kitchen Air Quality 		Performance Test

1

U.S. Green Building Council. LEED v4: Reference Guide for Building Design and Construction. Washington D.C.: U.S. Green Building Council; 2013: 37, 43-44, 542-43, 545, 541-552, 567, 605, 623, 645-53, 658-61, 682, 685-6, 723-4.
1.1.a

USGBC's LEED v4: Reference Guide for Building Design and Construction EQ Credit: Indoor Air Quality Assessment requires demonstration of formaldehyde levels less than 27 ppb.
1.1.b

USGBC's LEED v4: Reference Guide for Building Design and Construction EQ Credit: Indoor Air Quality Assessment requires demonstration of total VOC levels less than 500 μg/m³.
2

U.S. Environmental Protection Agency. National Ambient Air Quality Standards. 40 CFR part 50. http://www.epa.gov/air/criteria.html. Revised October 2011. Updated December 14, 2012. Accessed September 16, 2014.
1.2.a

The EPA's 2012 NAAQS require ambient air in cities to keep 8-hr average levels of carbon monoxide below 9 ppm and 1-hr averages below 35 ppm, not to be exceeded more than once per year.
1.2.b

The EPA's 2012 NAAQS requre PM₂.₅ to be less than 12 μg/m³ for a primary annual mean, secondary annual mean of 15 μg/m³ and a 24-hour concentration of 35 μg/m³, averaged over three years .
1.2.e

The EPA's 2012 NAAQS for nitrogen dioxide require a nitrogen dioxide annual mean less than 53 ppb.
3

World Health Organization. WHO Air Quality Guidelines for Particulate Matter, Ozone, Nitrogen Dioxide and Sulfur Dioxide. Geneva: World Health Organization; 2005: 9, 14.
1.2.c

The WHO's Air Quality Guidelines for Particulate Matter, Ozone, Nitrogen Dioxide, and Sulfur recommend 24-hour average PM₁₀ limits of less than 50 μg/m³.
1.2.d

The WHO's Air Quality Guidelines for Particulate Matter, Ozone, Nitrogen Dioxide, and Sulfur Dioxide recommend ozone limits at 100 μg/m³ 8-hour mean.
4

U.S. Environmental Protection Agency. A Citizen's Guide To Radon: The Guide to Protecting Yourself And Your Family From Radon. http://www.epa.gov/radon/pdfs/citizensguide.pdf. Published May 2012. Accessed September 16, 2014.
1.3.a

The EPA's A Citizen's Guide to Radon recommends radon levels to be less than 4 pCi/L.
Features>Air>01. Air quality standards