Issue link: https://hi.iaq.net/i/630729
Mitigating IAQ Problems 103 specialized maintenance skills. New items of equipment should be quiet, energy- efficient, and durable, so that the operators are encouraged to keep them running. Installation and Operating Costs The approach with the lowest initial cost may not be the least expensive over the long run. Other economic considerations include: energy costs for equipment opera- tion, increased staff time for maintenance; differential cost of alternative materials and supplies; and higher hourly rates if odor-producing activities (e.g., cleaning) must be scheduled for unoccupied periods. Although these costs will almost certainly be less than the cost of letting the problem continue, they are more readily identifi- able, so an appropriate presentation to management may be required. Conformity with Codes Any modification to building components or mechanical systems should be designed and installed in keeping with applicable fire, electrical, and other building codes. Judging the Success of a Mitigation Effort Two kinds of criteria can be used to judge the success of an effort to correct an indoor air problem: ■ reduced complaints ■ measurement of properties of the indoor air (often only of limited usefulness) Reduction or elimination of complaints appears to be a clear indication of success, but that is not necessarily the case. Occupants who see that their concerns are being heard may temporarily stop report- ing discomfort or health symptoms, even if the actual cause of their complaints has not been addressed. Lingering complaints may also continue after successful mitigation if people have become upset over the MANAGING MITIGATION PROJECTS INVOLVING SEVERE CONTAMINATION Cautions Locating the original source of a chemi- cal release or microbiological growth may only be the tip of the iceberg. Pollutants often tend to migrate through a building and collect in "sinks", from which they can be resuspended into the air. For example, particles accumulate on horizontal surfaces that are not subject to regular housekeeping; odors may adsorb (stick) to porous materials. Detailed surface and/or bulk sampling may be needed to locate such "second- ary" sources in order to solve an air quality problem. Depending on the problem, a detailed knowledge of chemistry, microbiology, building science, and health and safety may be required. Include air sampling along with regular inspections if needed. Decontamination of areas within an occupied building is especially critical. In the event of severe contamination, representative air samples should be collected to ensure that key indicators have returned to background levels and that the space can be safely reoccupied. Elements Identify the extent of contami- nation Develop a precise scope of work specifying exactly how remediation will be performed Monitor remediation to ensure work practices are followed Conduct clearance sampling Many routine IAQ problems can be corrected by a common sense approach not requiring special expertise. However, when complex exposure or contamination issues are involved, more detailed techni- cal assistance may be needed for success- ful remediation. Efforts such as those outlined above are sometimes needed to deal with severe contamination.