ASHRAE Journal - September 2022 - 30

COLUMN IEQ APPLICATIONS
The other major addition to the IAQP for both supply
air and exhaust air systems is the inclusion of a
qualitative evaluation that requires post construction
air quality testing to determine whether the design
contaminants and combinations of contaminants are
controlled to the design limits. The required test is to
be performed over an eight-hour period with the ventilation
system operating normally. The standard also
requires that the contaminant sensors be located in the
breathing zone and that they be capable of detecting
concentrations less than the associated design limit.
The required accuracy of certain sensors is also specified,
and these requirements are expected to develop
further in the future.
A New Cycle
As to the future, even though the 2022 edition of
Standard 62.1 has been finalized for publication, the
committee approved four more addenda to the 2019
edition for publication public review and one addendum
for advisory public review during ASHRAE's
Annual Conference in June. The topics covered by these
addenda include ozone generating devices, humidity
control and ventilation of health-care spaces.
Furthermore, the committee is responding to comments
on a proposed addendum to mandate density corrections
for elevation and requests from the United States
federal government and the ASHRAE Epidemic Task
Force to address lessons learned from the current global
pandemic.
Taking a closer look at some of the proposed addenda
reveals some of the complicated topics before the
committee. Addendum e specifies requirements for
the design of direct evaporative cooling systems and
includes a relative humidity limit of 65%, which has
been contrasted with the limit for mechanical and indirect
evaporative cooling systems that was changed in
2016 to a dew-point limit of 60°F (16°C). The approved
advisory public review that was concluded in early
September sought input on revisions that would include
a relative humidity limit for mechanical and indirect
evaporative cooling systems, which attempts to address
comments about the availability of dew-point controllers
on commercial HVAC packaged systems and exclusion
of climates at low risk of the deleterious effects
that the dew-point limit is intended to control. To
understand the purpose of the original change and the
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impacts of the proposed changes, the reader is invited
to review the ASHRAE Position Document on Limiting
Indoor Mold and Dampness in Buildings (https://tinyurl.
com/mrfkxc4y).
The reader may be forgiven for having missed the
review period earlier this year on Addendum j, which
addresses density corrections. The committee noted that
this addendum would increase outdoor airflow rates
by 10% or more in thirty-eight states and by more than
25% in sixteen states, yet the draft received only two
comments. One questioned the significant figures of
the conversion between IP and SI units, and the second
came from one of the negative votes on the committee
outlining the large market impact and the lack of evidence
indicating that current practice results in inadequate
ventilation. For a topic as controversial as this
one, the lack of public input was admittedly distressing,
particularly as this change would have large impacts on
energy expenditures and design practice. If the committee
issues an additional public review to address the
comments, we hope to receive more input, particularly
from those members regularly designing at higher
altitudes.
Although no addenda have yet to be drafted incorporating
the work of the Epidemic Task Force, there have
already been robust discussions about whether or not
minimum filtration requirements should be increased
permanently, and some advocacy for permanently
increasing ventilation rates. Others on the committee
have cautioned against permanent changes in response
to temporary conditions, and some are advocating a
middle ground that mandates design for higher filtration
and ventilation requirements while maintaining
the status quo for regular operations. Other ideas that
have been discussed include increased emphasis on air
distribution and air cleaning. The reader is reminded
to regularly check for proposed addenda at https://osr.
ashrae.org/ to help the committee with developing the
standard, or if they are so inclined, consider attending
our next meeting in Atlanta and join us in this important
work.
Acknowledgments
With gratitude to Wayne Thomann, Brian Hafendorfer
and Andy Persily for valuable feedback in the clarity of
this update.
https://tinyurl.com/mrfkxc4y https://tinyurl.com/mrfkxc4y https://osr.ashrae.org/ https://osr.ashrae.org/ https://ashrae.org/
ASHRAE Journal - September 2022

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