Dedicated Outdoor Air Systems (DOAS)
- By Kevin Miskewicz
- 04/01/16
An estimated 70 percent of all school
buildings have indoor air quality (IAQ) problems,
leading to an unhealthy environment. Many
common IAQ problems are associated with
improperly operated and maintained HVAC
systems, overcrowding, moisture incursion and
dampness, and presence of outside air pollutants.
IAQ problems have a greater impact on children
than adults, as children breathe a greater volume
of air relative to their body weight.
Additionally, occupants of school buildings
are close together, with approximately four
times the occupant density in schools compared
to office buildings. Mounting evidence
indicates that the quality of a school’s physical
environment affects educational achievement
and more attention is now being paid to addressing
IAQ issues.
With this in mind, the installation of a
DOAS system can dramatically improve indoor
air quality, creating a happier, healthier and
more productive environment for students,
teachers and staff, and some systems assist in
earning valuable LEED points. DOAS systems
condition up to 100 percent of outdoor air —
improving air quality, and reducing the load
on other HVAC equipment in a building. This
reduction in HVAC equipment load can result
in significant savings in energy consumption
over the lifetime of a system.
Humidity control is another great benefit
of these systems. Human occupants and
certain equipment in a school will generate
moisture, but most moisture comes from the
ambient conditions. If an uncontrolled amount
of moisture is continually added to a building,
a mold-friendly environment will result. Even
if mold is not a concern, the moisture content
in the air will affect the comfort level for
occupants. These and other benefits make
DOAS systems the perfect choice for school
buildings.
This article originally appeared in the issue of .
About the Author
Kevin Miskewicz is the director of Commercial Marketing with Mitsubishi Electric Cooling & Heating. He can be reached at kmiskewicz@hvac.mea.com or 888/979-9686.