Cantium Scientific MicroBio MB2 Operating Manual page 31

Alternatively, the following equation can be used to determine a corrected
count.
Where n is the number of holes on the sampling head, n
h
counted colonies and n
If the counted colonies, (n
(n ), then the equation will fail and the results cannot be trusted. If this is the
h
case, then the sample dish can be considered as overloaded with micro-
organisms and the user should consider lower sampling volumes.
The colony concentration is the corrected count per volume of air sampled.
The results are normally expressed in colony forming units per cubic metre.
To convert the corrected count to CFU/m
Where n is the corrected number of colonies counted and V
c
volume in litres.
For simplicity use our on-line tool to determine corrected counts and CFU by
visiting:
https://www.cantiumscientific.com/support/count-correction/
⎛
⎜
1.075
= n
⎜
n
c f
⎜
1.052 −
⎝
is the corrected count.
c
) exceeds the number of sampling head holes
f
CFU = 1000.
3
m
30
0.483
⎞
⎟
⎟
n
⎟
f
⎠
n
h
3
use the equation:
n
c
V
s
is the number of
f
is the sampled
s