“What air monitoring
issues should I pay
attention to when com-
missioning a new facility?” asked since you
This question was posed by an ALN reader. We asked Mike Eardley and Marco de Zan of Cannon Design to offer information on
air monitoring issues.
One of the most critical steps facility managers can take when seeking to understand air-monitoring in a new facility is com- mitting to a rigorous commissioning process. Proper commis- sioning can help determine appropriate requirements for air monitoring during the design review phase. Later in the commissioning process, comprehensive functional performance testing of building
systems prior to occupancy confirms design and construction components that
impact indoor air quality are properly installed and operating.
Using commissioning to help plan
ongoing air monitoring helps maintain strong conditions—the National
Institute for Occupational Safety and
Health (NIOSH) has found 52% of the
primary sources of indoor air quality
problems are related to inadequate ventilation. Delivering a healthy environment, serviceable systems, and energy
efficient operation are the overriding
goals of the commissioning process and
air monitoring is an important tool to
achieve these goals.
Commissioning focuses on two key
aspects of air-monitoring: the air quantity and the air quality.
One of the prerequisites in commis-
sioning before final functional testing
can begin is to have a complete air
balancing performed on all HVAC and
air-delivery systems. Air balancing does
It confirms adequate air is pro-
vided in all areas of a facility to
achieve the design intent.
It helps uncover and resolve issues
before occupancy, such as airflow
restrictions or leakage.
It improves energy efficiency and
functionality by uncovering unintended air distribution.
After initial duct pressure testing and air balancing is complete,
it is important to continue monitoring the airflow to verify initial
performances are maintained. This
is imperative in critical areas where
pressure relationships between zones
must be maintained like laboratories,
isolation rooms, and vivarium spaces.
During the commissioning process,
the commissioning authority verifies those pressure relationships are
maintained regardless of the HVAC
system’s operating mode, to provide
a safe and healthy environment. The
level of complexity can increase if
different areas have different heating and cooling requirements, heat
generation by specialized apparatuses,
exhaust requirements, and pressurization needs. A holistic and complete
approach studying the interrelationships between all of these different
components is critical for a complete
After the design team determines the
required air quality and conducts a
thorough review of reference standards,
the design phase commissioning review
will confirm this level is achieved in an
efficient manner. A calculated fixed-air
replacement rate might prove energy
wasteful and does not guarantee appropriate levels of fresh air. Air monitoring
can control the rate of fresh air intake
of a building dynamically based on
Air monitoring becomes even more
paramount when considering spaces that
may see a varying level of occupancy
and use. While a design may provide the
necessary level of ventilation at a worst
case allowable use, this use may never or
rarely occur. Air monitoring, and a commissioned integration with the building
automation system, allows the building
systems to cycle down when spaces are
not used at the maximum design capacity.
Air monitoring can also help