Sakraida is a principal engineer with Sakraida & Associates, LLC (Denver, CO) which is a consulting and forensic engineering firm. He has 30 years experience in the design, construction, and operation of cleanroom, pharmaceutical, laboratory, and other high-technology facilities. He is a member of ASHRAE, ASHE, ISPE, and IEST. He can be reached at firstname.lastname@example.org.
Appropriately enough, a good variable airflow design accommodates and refines a number of design variables. Particle monitoring strategies, minimum supply air calculation, HVAC sequencing, and space pressurization are just a few stops on the way to spotless performance.
motor-driven vapor compression chillers are much more energy
efficient than absorption chillers, then why are we even having this
conversation? In a hunt for LEED® points or in applications with
certain demands, absorption could be just the ticket to
sustainability and/or economy.
OK, so “easy” may not be a word that comes to mind for designing such
sensitive environments. However, that doesn’t mean you can’t produce a
solid cleanroom design by tackling issues in a logical sequence. This
article covers each key step, down to handy application-specific tips
for adjusting load calculations, planning exfiltration paths, and
angling for adequate mechanical room space relative to the cleanroom’s
In addition to serving as a handy reference on the various
dehumidification technologies and their profiles, this article uses a
manufacturing scenario to explore load-related questions and other design
pitfalls. Will human occupancy make much of a difference? What valves does your
humidifier have? And exactly what’s in that room, anyway?
Leaning on experience and data from various K-12 cities and projects, the author pursues some less conventional design approaches. They may revolve around radiant heating and/or cooling, but depending on school size and other factors, the smart use of heat recovery, DOAS, and improved central plants could also put a project on the HVAC honor roll.