Microbial count

If there is no microbial colony found on settle plate ,observed count will be written as zero or nil or <1?


Why we can not write zero?

0 mean no chance to occur
Nil mean probabiliy present


Good answer


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Suppose 4 settle plates are exposed in B grade area. 1st plate contain 1 colony,2nd contain 1 colony,3rd contain 2 colony 4th contain 1 colony .What will be result? Area is pass or fail?


Yes,but how many count will be considered for result?

7 cfu are allowed in class B

in above example, total 5 colony found in 4 plate. so average count will be 1.25.Area is pass. maximum 5 count is acceptable in grade b as per EU GMP 2008.

yes you r right

Dear Sajjad 7cfu are allowed or 5Cfu? please

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