Indoor air quality investigation may not always produce the expected results and sometimes the results of such investigation are often inconclusive. This is particularly true in the air contamination is only one of the suspected causes of a particular problem or the airborne contaminants are present only sporadically, for short periods of time or sometimes only at one occasion.
I have recently finished such investigation into office indoor air quality which has not yelled conclusive results, at least not on mine part. The problem occurred in a modern office building shortly after a small part of the building suffered a minor water leak on one of the upper floors. Some office staff occupying the room directly below the flooded room have experience quite severe health symptoms described as dizziness, lost of orientation and general unwellness. The complicating factors in this investigation have been that the room under investigation has not actually been affected by flooding in any particular way, the flooding has occurred 2 days before the health related incident, symptoms occurred only once and my investigation took place about a week after both incidents.
I have evaluated whole range of possible contaminants typically causing indoor air quality problems such as airborne mould spores, particles, ozone, temperature 7 humidity and chemical contaminants and others. Sampling and analysis of all air related contaminates turned out to be inconclusive. However the investigation help to prove that the incident experienced by the staff was not likely indoor air quality related.
The business took this incident very seriously and alongside with my investigation have submitted samples of water and food consumed for detailed chemical and microbiological analysis. Most of the samples did not provide definite cause of the symptoms but it has been found that some of the consumed sandwiches had very high pseudomonas bacterial count. Food poisoning produces quite specific symptoms which were not consistent with the symptoms experienced by the staff. If however the food was responsible it is possible that some of the bacteria present could have produces toxins which could have caused the symptoms.
Any investigation into adverse health symptoms experienced by building occupants is a complex problem and often not related to the building itself. Sometimes the ill effects are purely person related and sometimes external factors such as nearby industrial unit or airport can be the cause of the problem. In any case well structured approach in any investigation is required to eliminate or confirm the potential ill health causing agents or processes.
By Tomas Gabor
