When we do perform “viable” sampling, using a sterile petri dish and agar, it is performed using an impactor connected to a high-volume sampling pump, that actively samples a specified volume of air, giving an analytical result in a quantifiable unit, such as colony-forming units per liter of air (CFU/L). These results are not quantitative.Ī professional industrial hygienist would never use this type of passive sampling to identify mold spores. The problem is that these are passive sampling devices, without a predetermined volume of air that is being sampled, with a sampling media that is easily contaminated, and with analytical results that are almost meaningless in terms or indoor air quality and in using as a comparison to spores found outdoors. You then let the samples sit for a determined period of time, put the lid on the sample, and send it to a lab. These kits use a growth medium, called agar, that is added to a petri dish. Some DIY kits test for “viable”, or living, spores only. What are the corrective actions needed to effectively clean-up the mold?Īll of these answers should be given in a thorough mold investigation report performed by a professional industrial hygienist.ģ) DIY mold testing kit lab results are not meaningful – There are multiple types of mold testing used by professionals and in DIY mold testing kits. If there is obvious visible mold growth, then there is likely much more that is hidden from the eye. Industry professionals not only use the comparative outdoor sample to determine and indoor samples’ relative weighting, but also years of scouring over air sample results and the information gained during the visual inspection to determine their recommended corrective actions.Įven if you are able to discern that there is an indoor mold issue from the analytical results given to you by a do-it-yourself (DIY) mold testing kit, how do you fix the problem? Where are the elevated spore counts coming from? Where is the source of water that is causing this mold growth? Where is the mold in my home? Because there are no regulatory levels, determining whether an indoor air sample is “high” is very difficult. Reading mold analytical results is a science in itself. Even if you hire a professional industrial hygienist to perform a mold investigation for you, without a strong visual inspection, you will have wasted your money. Even if you hire a professional industrial hygienist to perform a mold investigation for you, without a strong visual inspection, you will have wasted your money.Ģ) No recommendations for corrective action - As mentioned above, recommendations for corrective actions are impossible without having first performed a visual inspection. Recommendations for corrective actions are impossible without having first performed a visual inspection. Mold laboratory results are meaningless without knowing where the potential areas of growth are occurring. The visual inspection is so important because it is the initial starting point from which an investigation must begin. It should be performed by an inspector who has had years of training in the use of this equipment and in the understanding of building systems, exterior finishing systems, and identifying mold spores and the locations they are likely to grow. A good visual inspection will incorporate infrared thermographic readings, moisture meters, borescopes, temperature meters, relative humidity meters, and dew point measurements. Identifying the locations of these leaks, especially those that are not obvious, can be very difficult. Without a source of water, mold is not likely to grow. 1) No visual inspection – By far the most important part of any mold investigation, before a single air or surface sample should be collected, is a strong visual inspection for evidence of water damaged building materials, water intrusions, leaks, and signs of visible mold growth.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |