Healthy Indoors Magazine
Issue link: https://hi.healthyindoors.com/i/917400
Healthy Indoors | 17 and a timeline of occurrence even before I took the instrumentation out of the box. Based on the inter- views and a quick look above the ceiling, the source was identified as a corroded sewer vent line inside of a return air plenum. The odor went away when the air handler was on economizer and was strong when the system was operating. Even simple tools may be useful in helping evalu- ate the indoor environment before you need to bring out the expensive monitoring equipment. One project I was asked to get involved with was former military housing that had indoor air samples collected for pes- ticides that were used to treat the soil before the slab was poured to reduce termite potential. The samples were exceeding exposure criteria and the units could not be re-occupied until a resolution was found. After interviewing the State Inspector about how the units were built, I was able to show him with a smoke tube and a flashlight the soil gas pathways, especially when the attic ventilation fan was turned on. No oth- er testing was needed, but without having someone there who was familiar with the way these units were built it might have taken a lot more sampling and lab analysis to find the pathway. Listening to occupants complain is not always easy and sometimes it may feel like we have crossed over into psychology, but I have found that most just nervously wondering if we are looking for drugs. Data for a variety of parameters can be downloaded and time sequenced to look for patterns or correlations to the indoor issue being investigated. Although the new technology is very useful at assessing the physical parameters in a building, one IAQ tool that I find has weathered the test of time is the occupant interview process and actively listening to occupant concerns. Typically, when we conduct an IAQ assessment we might be there for only a day or so and we do not get to experience the temperature swings, filter change-out, or the building during different weather and operating conditions. This is where occupant interviews will help us identify the possible problem areas. Interviewing the affected occupants will not only allow them an opportunity to discuss their con- cerns and give them someone who will listen to them, but it may help in identifying patterns, odor hedonic tone, and building operational issues that you might not be aware of during an IAQ survey that is just a snapshot in time. The occupants are there every day and although they might not totally understand air ex- change rates, carbon dioxide levels, or background dust levels, they know how they feel and how they re- spond to the workspace they are in. Sometimes you can find the problem without conducting any mea- surement at all. One project I was asked to investigate was a per- sistent odor in a large office in Connecticut. It was dif- ficult to arrange an in person interview of the primary complainant because she said the odor made her sick and she could not come to the office, so much of the interview was conducted over the phone. The occu- pant was complaining about a strong odor and though they moved her several times the odor persisted. Un- fortunately the complainant was not there when I went there to conduct sampling, all the baseline parameters were normal, and there was no obvious odor source inside or outside the building. When I was finally able to meet the complainant, the source of the odor was obvious. I reported this to the office manager and let them handle what was probably a difficult conversa- tion. They did become a repeat client. Another indoor air investigation that I conducted at a very nice country club in Maryland also involved an intermittent odor. When I interviewed the occupants I was able to get a very good description of the odor