What’s In the Air? by Yuseph Sleem
Indoor Air Quality (IAQ) is a term which refers to the environment within and around buildings and structures, especially as it relates to the health and comfort of building occupants. IAQ is affected by a wide range of pollutants from many sources and poor IAQ may cause occupants to experience symptoms such as headache, fatigue, nausea, or skin irritation. When truly caused by the building’s IAQ, these symptoms typically subside upon leaving the building. Potential sources of IAQ problems include: cigarette smoke, airborne dust and particulates, perfumes, cleaning products, microbial contaminants such as mold, vehicle exhaust, or gases such as carbon dioxide (CO2), carbon monoxide (CO), and volatile organic compounds (VOCs) used in or around occupied spaces, as well as environmental factors such as ambient temperature, relative humidity, and ventilation.
It is important to appreciate that each IAQ investigation presents a unique set of circumstances. The mere presence or absence of one or more of the typical contaminants cannot simply be interpreted as being the cause of an IAQ problem. This is where EH&S factors in. EH&S can investigate IAQ concerns and help determine the source of an IAQ issue and recommend appropriate mitigation strategies. A typical IAQ survey may involve investigating several IAQ parameters, such as temperature, humidity, building ventilation, CO, CO2, and VOCs levels, which EH&S can accomplish with portable, direct-reading instruments.
The objective of each IAQ survey is to identify the source and cause of the IAQ concern and take quick, corrective action. In instances where the likely resolution of an IAQ issue involves addressing ventilation concerns, including adjusting temperature, adjusting air distribution, or cleaning or maintenance of the ventilation system (e.g., cleaning supply registers), Facilities Management should be contacted directly by the occupant to coordinate these services. If IAQ issues are not resolved by Facilities making adjustments to or performing maintenance on the ventilation system, EH&S should be contacted for additional consultation.
When it comes to mold and IAQ, EH&S’s strategy differs slightly from that of other contaminants of concern. As noted earlier, most contaminants are measured by direct-reading instruments or by collecting samples for laboratory analysis. Since mold spores are ubiquitous and will almost always be found in air samples and often in surface samples, sampling is not an ideal approach for an initial mold investigation. Accordingly, and in line with NYCDOH recommendations, EH&S’s strategy includes a visual inspection to identify the presence of mold or conditions that would encourage mold growth, such as damp or wet surfaces or materials. If found, small, isolated areas of mold growth can safely and effectively be addressed with contact disinfectants. Larger areas may require removal of the contaminated material. Since mold requires moisture and nourishment to grow, identifying the source of the moisture (i.e., leak, rainwater intrusion, condensation, excess humidity) and removing the nourishment (i.e., damp materials) is essential to correcting a mold issue. In some instances, damp materials can be effectively dried to minimize the potential for mold growth (i.e., typically within 24-48 hours of becoming wet), and in other instances they will have to be discarded. All water intrusion events must immediately be reported to Facilities Management so they can take prompt action.
Converting Counts Per Minute (CPM) To Disintegrations Per Minute (DPM) Laboratory survey results must be reported in DPM. Survey meters and liquid scintillation counters (LSC) may not read out directly in DPM. The counts per minute recorded from the dial or printout must be corrected for the counting efficiency. Different isotopes have different counting efficiencies. Please refer to the email message of August 24, 2012 for specific procedures.