4 FM quick reads on IAQ
1. Air Balancing for Good Indoor Air Quality
To achieve good indoor air quality, periodically air balance your HVAC system.
Air balancing can help alleviate hot or cold spots, drafty or stagnant areas, insufficient or excess humidity, and noise problems. The goal of air balancing is to deliver the proper amount of air, minimizing imposed resistance.
Periodic air balancing as part of an overall IAQ program can improve air quality, and at the same time, lower energy costs and lengthen system life.
Addressing Indoor Air Diffuser Maintenance
Everyone has seen air diffusers jammed with files or piled with boxes, either negligently or as an effort by employees to satisfy their personal thermal comfort needs. However, it is important to make sure that supply air diffusers serving occupied spaces are not blocked.
Obstructed supply air diffusers can ruin proper air balance. When this occurs, some areas receive too much supply air, while others receive too little. Also, improper air pressure relationships between the building and the outdoors, as well as between key areas within the building, can develop. This facilitates pollutant transfer.
If occupants are complaining of drafts, several remedial options exist: occupant locations can be changed, diffuser locations can be moved, or a different diffuser design can be used. Some of these options may require that the air system be rebalanced.
Managing IAQ During School Renovations
According to the U.S. Environmental Protection Agency (EPA), one of the major contributors to bad indoor air quality in schools is renovation and repair activities.
Existing schools can have some fairly old technologies in them, such as lead-based paint, or flooring with asbestos. Or past water damage might have caused unseen mold issues in walls. Construction activities themselves are dusty and new building materials might off-gas.
Especially when work is going to be done while the school is occupied, demolition and construction activities will have to be conducted with care and greater supervision.
Some of the steps that EPA recommends for protecting building occupants, particularly children who are much more affected by indoor air quality issues than adults include:
-testing for the presence of lead and asbestos.
-keeping occupants as far away from demolition or construction activities by physical distance, proper ventilation and barriers such as plastic sheeting.
-doing everything possible to keep pollutants confined, such as wet sanding drywall or keeping lids and caps on solvents, adhesives and paints as much as possible.
For other suggestions from the EPA on how to mitigate the negative effects of renovation on IAQ in schools, check out http://epa.gov/iaq/schooldesign.
Radon and Indoor Air Quality
After the hubbub of the holidays dies down, you might turn your attention to your facilities indoor air quality. January is National Radon Month, and while the EPA focuses it's effort on private residences, any commercial facility with below-grade construction might be affected by this cancer-causing gas.
Radon is a radioactive gas produced by the decay of radium and occurs naturally in soil and rock. It is second only to smoking as a cause of lung cancer in the United States, according to the EPA.
Homes have the highest ratio of contact with the ground, and hence the highest risk for exposing their occupants to radon. The current EPA action level for indoor radon concentrations is below 4 picoCuries per liter (pCi/L).
Just because commercial facilities are not the focus of national radon efforts does not mean they're not affected. In 2007, a group of physics students found elevated levels of radon in a basement library at Princeton University. Subsequent testing by the University found elevated levels of radon in other parts of the campus, including dorm rooms and even one basement music practice room measuring at 205 pCi/L. The university has since taken steps to remediate the areas with radon issues and the school will be retested every ten years.
If people in your facility spend any appreciable time in below-grade spaces, it might be a good idea to test for radon. It's a pretty straightforward test and remediation strategies are well established. For state radon resource information, go to www.epa.gov/radon.