LCS Laboratory Inc., has developed a new air sampling method for the evaluation of Time Weighted Average (TWA)- the concentration of mold in air. Our sampling procedure is based on NIOSH 7400 method. Samples are collected on 25mm conductive cowl cassettes also known as “PCM” cassettes. Mold spores are collected on high efficiency 0.8 micron pore size MCE membrane at a flow rate of 1-14 L/min for up to 1000L of air. The typical reporting limit is 50 mold spores per sample, which corresponds to 250 spores/m3 on a 1000L air sample. Samples should be collected “open face” in order to achieve a uniform distribution of dust on the filter. The analytical procedure is proprietary to LCS Laboratory Inc., and includes extraction of the mold, and spore count under a light microscope at magnification 400. You can collect the sample for 4-8 hours to achieve sufficient sensitivity.
Advantages of the new method:
- This is the only method hat measures TWA mold concentration
- Method is not susceptible to short term fluctuations of mold concentration in air
- Method utilizes widely available standard PCM cassettes and portable personal sampling pumps
- Method is suitable for personal exposure assessment
Disadvantages of the new TWA Mold Spore method:
- Method is not a standard method
- Method is not suitable for Short Term Exposure Limits (STEL) assessment.
- The test is only available from LCS Laboratory Inc.
If you need mold sampling, or would like to discuss your project, please email us at your convenience.
at 10:00 am
I would like to discuss your use of the 7400 method for the collection of mold spores. I have been promoting it for 15 years. Congratulations. It is a method I teach.
at 9:12 pm
Hello Dr. Spurgeon. Thank you for your kind comment. We also believe that this technique can find its users. We are planning to use similar approach for personal/TWA sampling of pollen.
Sincerely yours
Stepan Reut Ph.D.
at 9:24 am
Hi Stepan. Been using this method for over 15 years with the Bi-Air filter cassette; two AIHA journal publications. Check http://www.expertonmold.com for articles. Works very well, and accepted by courts. Would like to support your efforts in any way possible. In classes, there seems to be a grassroots understanding that current methods “don’t work”; but this position is not shared by IAQ “management”. Would appreciate any communication thru e-mail: jospur46@gmail.com. Would like to send you some attachments.
Joe