How to state Air / Yeast & Mould count ?
Hi,
Please do help me understand on my query.
If for example, the actual result of YM for Air test is 8 cfu..
How do I state it in the report.
Thank you for your support
How have you performed the test that generated the 8cfu result?
Was this a plate or an air sampler?
Broadly you're trying to answer the question: 8 cfu "per what"?
For example if it's a plate then you know (or can calculate) the surface area, and you know how long you exposed it for the sampling process, so you can fairly readily turn your result into a cfu per m2 per hour figure (or similar).
In addition to pHruit's advice If this is compressed air, the pressure should be reported. Sampling devices are usually calibrated to a specific plate at a specific PSI (kPa, or Bar).
e.g.
*Method - Isolated Plates exposed to Air Compressor Air for
Are you talking about environmental air testing or compressed air testing? We use 3M Rapid Yeast and Mold Petrifilm plates for our compressed air testing and since we manufacture packaging, we are excluded from the environmental air testing. I would think you would need a high count threshold "The target is a count of 10 or less per 4 sq in" or whatever the medium size you are using indicates it should be. Sampling method, locations, duration of exposure, hydration method (if applicable) and supplies, person performing sampling, person verifying the sampling was carried out etc.
Are you talking about environmental air testing or compressed air testing? We use 3M Rapid Yeast and Mold Petrifilm plates for our compressed air testing and since we manufacture packaging, we are excluded from the environmental air testing. I would think you would need a high count threshold "The target is a count of 10 or less per 4 sq in" or whatever the medium size you are using indicates it should be. Sampling method, locations, duration of exposure, hydration method (if applicable) and supplies, person performing sampling, person verifying the sampling was carried out etc.
Was wondering how you use the plates for testing. Do I need to add a solution after exposure to the plate or just spray with the air and that's it. Thanks for the help.
packman156, I hydrate the petrifilm with 1ml sterile diluent. I use eye wash solution but you can also just use distilled water from a new container. I write the location of the sample on each then take them to the location and blow air on them. For that, I use a sterilized tube I made specifically for this testing and an adjustable blower nozzle (got it from McMaster Carr) closed down to a slow flow to prevent disturbing the plate gel. I blow air at the gel for 1 minute then put them in an appropriate plate to wait for the results. I also hydrate a plate for each of the rooms, in which I am testing the compressed air, for an ambient air sample. Those I leave exposed on a flat, horizontal surface in the room for 30 minutes. I have used this method for over 6 years and it has been accepted as adequate by all auditors so far.