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Commercial - FAQ

I see dirt streaks around my registers, do my ducts need cleaning?

No, dirt streaks are almost always caused by poor design. All air has dirt in it. If the speed (velocity) of the air exiting your register is higher than it should be the dirt is actually impacted on the wall or ceiling surface. A solution is to add another register from the same duct serving this register; this reduces the speed of the air by distributing it to two registers instead of one. It will also reduce the air noise coming from the original register.

Be sure your facility maintains a positive interior air pressure.

It is very important that your building exhales instead of inhales. A slight positive pressure will keep outdoor contaminants from entering your building through the path of least resistance such as when a door opens etc.

My air conditioner smells when it starts up, is there a problem?

There could be. This odor is sometimes referred to as dirty socks syndrome. It is typically caused by dirty cooling coils that are contaminated with mold. Cleaning the coil may work for a short period of time. The proper solution is to clean and disinfect the coil and install an ultraviolet germicidal light source to prevent the re-contamination of the coil. The addition of this UV light provides some additional benefits such as better heat transfer on the coil and a significant reduction of mold/fungi/bacteria in the air stream.

What are ultraviolet lights and are they a benefit to me?

Ultraviolet lights for HVAC systems generate a UV light in the germicidal band range. The UV light kills the mold and bacteria by destroying its DNA and stopping it from reproducing. This can and will improve the indoor air quality in your home. And, if properly placed near the cooling coil will help eliminate microbial problems associated with wet cooling coils.

What is Sick Building Syndrome?

The ASHRAE definition is as follows: SICK BUILDING SYNDROME: "SBS" If more than 20 percent of the building occupants complain of such problems as headache, eye irritation, fatigue and dizziness for more than two weeks; if the symptoms are relieved when the complainant leaves the building; and, if no specific cause of the problem can be identified. (ASHRAE Journal, July 1988, p.40)

Are some HVAC systems more susceptible to IAQ complaints?

Well maintained constant volume HVAC systems generally have fewer complaints than Variable Air Volume (VAV) systems. The main reason is that a properly maintained constant volume system provides a constant airflow to the occupants and consistently provides outside for dilution purposes. VAV systems due their inherent design vary the airflow to match the actual load regardless of the number of occupants in the space. The problem can be corrected, contact us for more information.

What is mold and fungi?

Basically mold and fungi are organisms that break down organic matter such as wood and other cellulose materials. For more in-depth definition see, IAQ Glossary.

What can cause poor indoor air quality?

Poor IAQ can be caused by many things such as: poorly designed HVAC systems, HVAC systems not being properly operated or maintained, not enough outside air being brought into the system, poor air circulation. It is important that IAQ complaints be documented and that appropriate professionals are used to determine the extent, if any, of the problem. Ignoring an IAQ problem will only make it worse.

What can I do to prevent an indoor air quality problem?

· First, know your HVAC system and keep all system documentation.
· Select a competent quality contractor to service your equipment.
· Properly maintain your HVAC system and periodically have an independent third party verify that proper maintenance is being done.
· Use high quality filters
. Be sure the proper outside air is being brought into the system per ASHRAE 62 standards.

Guidelines for Basic Indoor Air Quality

The US EPA, NIOSH and CDC have developed guidelines for maintaining acceptable indoor air quality.
· Proper ventilation. Document that ventilation rates are consistent with ASHRAE 62 standards.
· Provide acceptable comfort levels for most occupants (ASHRAE 55-1991).
· Maintain mechanical equipment and building surfaces in reasonably sanitary condition.
· Isolate significant emission sources from occupied spaces.
· Control major sources of contamination promptly.
· Control humidity and moisture intrusion.
· Conduct operations, maintenance, and construction activity to minimize occupant exposures.
· Resolve problems quickly.
· Communicate with all occupants.
· Document, document, document.

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