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What's Your IAQ/IEQ?

Posted September 12, 2007 1:00 AM by Steve Melito

Perhaps the two most important aspects of any given commercial mechanical system that provides building occupants with first-rate Indoor Air Quality (IAQ) and Indoor Environmental Quality (IEQ) are a superior ventilation air delivery system and proper humidity control. Mechanical engineers can use a variety of options to achieve excellent IAQ and IEQ. While some provide decent ventilation, they fail to provide adequate humidity control, and vice-versa. In this Engineered Systems article we discover a commercial mechanical system that fully meets both aspects of a properly designed dedicated outdoor air system (DOASs). How do you achieve the optimum IAQ and IEQ?

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Guru

Join Date: Aug 2007
Posts: 553
#1

Re: What's Your IAQ/IEQ?

11/12/2007 3:42 PM

dedicated outdoor air sytems......environment conservetionist ...please step in.. stop pollution plant more trees

I keep my office well ventilated opening all windows open and let polluted air enter our premises and choke us with CO2 ,seriously to control humidity we use airconditioning

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Anonymous Poster
#2

Re: What's Your IAQ/IEQ?

11/21/2007 11:39 AM

I'm all for reducing outdoor air quantities to reduce the energy and environmental costs of conditioning all of that air. However, I think CO2 sampling is only appropriate for large spaces, but overkill and expensive for many other common use types. For a suite of offices, I think code should allow airflow to be controlled by temperature only - if occupants are present, they will generate a load, and ventilation rate will increase. During unoccupied periods, I'd let airflows drop to a very low minimum, say the code rate for corridors or storage space. As to outdoor air fraction, I'd control it at the air handler based on a diversified block load. No one can convince me that O2, CO2, other contaminants wouldn't diffuse throughout a building, the same way water vapor and humidity does. The requirements to analyze required outdoor air fraction to a mixture of spaces; and to analyze ventilation effectiveness of air outlet devices in a room are, to me, compulsive overreactions to the fear of predatory lawsuits.

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