CFU count by settle plate method

CFU measures dead cell or living cell?
Visible colony contains how many organisms?
How you will interpret your result if no any visible colony found in settle plate?

CFU means colony forming unit. As this word shows the units which can form a colony. It means living cells.
A visible colony may contain millions of organisms.
If you don’t find any colony on a plate then you can write 0cfu/plate.

formula to calculate cfu/ml please

CFU/ ml = No. of Colonies x Dilution Factor/Volume of sample added

guidelines says for class A limit is less than 1, is there is any condition when colony can b less than 1.

nd why guidelines says less than 1, why not 0

Thank you

sir i want to make format for test report for microbiology ?can you help me with the same

0 indicate there is no possibility of microbes but <1 or nil indicate possibility is there

If you have analyzed 1 ml sample in duplicate and 1 plate has one colony then result would be (1+0)/2=0.5 cfu/ml
In this condition you can pass the test if limit is <1 cfu/ml