GREEN BUILDING ; RISK COMMUNICATION
How to Put the IH in LEED
Green Buildings Need Industrial Hygienists’ IAQ Expertise
BY DALE WALSH
No one has ever “built green” as well as the Lascaux cave
dwellers. Famous for their prehistoric cave paintings, the cave
dwellers’ domicile in what is now France had little negative impact on the environment or natural resources. (I would like to
think that the cave dwellers’ consulting paleo-hygienist had a
lot to do with cave choice and maintenance.) The space was still
livable 15,000 years later, and their paintings were in great
shape—until modern man started messing around with the indoor cave environment. Apparently, a ventilation system installed to accommodate visitors has created conditions for the
growth of a paint-damaging fungus (mostly Fusarium species).
Today’s industrial hygienists have the knowledge to help ensure a high quality, sustainable indoor environment. We’ve been
making recommendations for improving indoor air quality (IAQ)
for many years. However, the designers and builders of today’s
green buildings continue to make mistakes that negatively impact
IAQ in buildings with supposedly superior indoor environments.
IAQ and LEED
The two main IAQ issues typically addressed in green building
are the following:
• the indoor circulation of outdoor air to dilute building and
occupant pollutant sources
• the elimination or limitation of indoor pollutant sources
The American Society of Heating, Refrigerating, and Air-
conditioning Engineers (ASHRAE) standard 62.1, “Ventilation
for Acceptable IAQ,” is usually referenced as a minimum require-
ment for green buildings. Outdoor air pollution control agencies
such as California’s South Coast Air Quality Management District
(SCAQMD) have established limits on volatile organic compound
(VOC) content for building materials, such as paints and adhe-
sives, to limit their impact on outdoor air pollution. Many green
building systems reference these VOC limits, which may not be
appropriate for addressing their contribution to IAQ.
In the United States, the most widely used rating system for
green building is the U.S. Green Building Council’s (USGBC)
Leadership in Energy and Environmental Design (LEED) system.
The indoor environmental quality (IEQ) section of LEED for new
construction has only two prerequisites: the provision of minimal outdoor air, as described in the ASHRAE 62.1 standard; and
elimination or control of indoor environmental tobacco smoke.
The other aspects of IEQ are optional points or credits toward
achieving a LEED rating for the building.
Credit 3.1 addresses IAQ management during construction, a
broad area that encompasses the need to keep the interiors of
ducts clean and dry before installation, the control of dust inside
the building, etc. However, the credit does not address many
other issues that affect IAQ, such as the use of mold-supporting,
cellulose-containing materials in high-water-use areas (
bathrooms, janitor’s closets, kitchens, etc.); prevention of the installation of asbestos-containing materials; and others.
Credit 3.2 has two options. Option A is flushing the building interior with a specified amount of outdoor air. Industrial hygienists understand that a one-time air flush will not adequately
remove air pollutants in cases where pollutants are emitted continuously over a long period of time.
Option B of credit 3.2 concerns pre-occupancy air testing, an
issue that many industrial hygienists have dealt with recently.
But the current LEED requirements for air testing are poorly defined, and the allowable levels of pollutants specified in Option
B are often inappropriate.
For example, the current LEED IAQ testing protocol estab-lishes a 500 µg/m3 limit for total volatile organic compounds
(TVOCs). LEED suggests that testing methods be consistent with
the old EPA Compendium of Methods for the Determination of
Air Pollutants in Indoor Air (also known as the IP methods).
These methods are hard to find and not always appropriate;
many labs don’t perform them. LEED does not require specific
testing methods, so anything from colorimetric indicator tubes
and photo-ionization detectors to Summa canister and multi-sorbent tube methods may be considered acceptable. In addition,
TVOCs may not be appropriate for assessing IAQ: even when
reputable methods and labs are used to determine TVOCs (e.g.,