Avoiding IAQ Problems – EBN Recommendations
Building design
• Design a pleasant and comfortable space. Many workplace air-quality complaints are exacerbated—or even caused—by poor lighting conditions or thermal discomfort. • Consider providing operable windows, even in building types where they are no longer the norm. In multifloor buildings this strategy necessitates careful airflow isolation between floors and connections to stairwells, elevator shafts, and atria. • Provide a separate smoking room when clients smoke. Well-ventilated, designated smoking areas are now common in commercial buildings (when smoking is permitted at all); the same idea can also be incorporated into houses. • Follow accepted practices for radon control and future mitigation, should it prove necessary: a layer of crushed stone under concrete slabs, polyethylene vapor retarder, capped 4”-diameter pipe through slab, sealed sump cover, etc. • Eliminate or minimize the need for pesticide treatments around buildings through careful detailing (for example, termite shields and separation between wood and soil). • Install outdoor-venting central vacuum systems in houses.
HVAC design
• Give occupants as much personal control over airflow, air temperature, and lighting as possible. Many comfort and irritation complaints are exacerbated by the feeling of a lack of control over one’s immediate environment. • Avoid using hard-to-seal building cavities, such as dropped ceiling plenums, for air movement. • Do not install combustion appliances unless they are sealed-combustion or power-vented. • Avoid gas ranges. If clients insist on gas cooking, argue at least for an electric oven—combination ranges are now available. • Install quiet kitchen range fans that exhaust to the outside in all homes. • Specify continuous or intermittent mechanical ventilation in all homes. Central, ducted, balanced ventilation systems are most effective. • Locate fresh air intakes away from likely sources of polluted air. • Avoid situations in which polluted air can leak into ducts, air-flow plenums, or mechanical systems. • Encapsulate or remove asbestos insulation on old boilers and hot water or steam pipes. Use certified asbestos abatement contractors for removal. • Design HVAC systems so that all equipment is easily accessible for regular maintenance and cleaning.
Material selection
• Avoid products made with urea-formaldehyde binders; if they are used, emissions can be reduced by surface sealing. • Ask manufacturers of interior finishes and furnishings for reliable data on offgassing from their products, such as the information available from Steelcase, Inc. (see EBN Vol. 4, No. 3). • Consider alternatives to wall-to-wall carpeting. Suggest hardwood flooring, tile, slate, natural linoleum, or natural cork as possible alternatives. If considering such flooring alternatives, carefully examine the adhesives, sealers, varnishes, and cleaning agents that could result in VOC emissions during installation and maintenance. (Some experts also claim that the linseed oil in natural linoleum can be a problem.) • Avoid the use of carpets in areas of the building that might be exposed to moisture or heavy pollutant loading, such as building entrances, washrooms, kitchens, and basements. • Choose coatings with the lowest VOC levels available, while still ensuring acceptable performance. • Use only low-VOC carpet adhesives or, better yet, adhesive-free systems such as tackless strips or the Velcro®-type Tac-Fast™ system.
Installation and commissioning
• Oversee a thorough test of all building systems to ensure that they are operating as designed. Consider making a videotape of this procedure for use in training maintenance staff about system operations. • Operate the building ventilation system at maximum fresh air for at least several days (and ideally several weeks) after final finish materials have been installed before occupancy. • Operate HVAC systems for optimum air exchange, appropriate relative humidity levels, and energy efficiency. • Suggest to building owners that smoking not be permitted inside the building, and educate occupants about indoor air quality effects of personal care products such as perfumes and hair sprays.
Ongoing maintenance issues
• Suggest that commercial building owners designate an IAQ manager who will be responsible for matters relating to indoor air quality (approval of cleaning agents, scheduling of painting, etc.) • Specify a comprehensive regime of preventive maintenance and training for the building maintenance staff. Particularly important is the regular replacement or cleaning of air filters. • Use only vacuum systems with high-quality filtration. • In mechanically controlled buildings, maintain relative humidity below 50% and above 30% if possible. Some experts now recommend that humidity levels be kept below 40% R.H. • Keep the building clean. • Use nontoxic cleaning agents and low-toxic pesticides.
