Difference between zero and nil

What is difference between zero and nil in case of cfu count

Zero and Nil are same in the case of the microbial count.

Can we write zero count if no cfu count found in plate exposed under LAF

There is no specific reason to write nil instead of 0 counts. 0 may be manipulated easily making it 05 or 10 etc. therefore nil is better to write.


We can’t write NIL in terms of CFU count. we have to write only 0(zero).No area/ zone is free from microbes we can just controlling or minimising the contamination.because no test is long enough to say that area is free if contaminaton.
If you write 0(zero) then it says it is under control of that particular criticalness.

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Nil term is probability based so if u write nil it means it is not completely free of micro organisms.nil is suitable term to represent <1cfu count while zero represents there is no possibility of any micro organism.

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Yes, exactly like what you said

Your statement is opposite to my statement.are you agree that <1cfu count should be denoted as nil in place of zero.

Can tell me as per USP at class 100 how many CFU/cubic feet(air born viable).and at class 10000 how many CFU/cubic feet.

As per USP <1116> for ISO 5 <1 cfu,ISO 6 <3cfu ,ISO 7 <5 cfu ,ISO 8 <10cfu.

dear manoj your statement applicable for only sterile plant wright na.