Cantium Scientific MicroBio MB2, Руководство по эксплуатации

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Alternatively, the following equation can be used to determine a corrected
count.
Where
n
h
is the number of holes on the sampling head,
n
f
is the number of
counted colonies and
n
c
is the corrected count.
If the counted colonies, (
n
f
) exceeds the number of sampling head holes
(
n
h
), then the equation will fail and the results cannot be trusted. If this is the
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
3
use the equation:
Where
n
c
is the corrected number of colonies counted and
V
s
is the sampled
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/
n
c
=
n
f
1.075
1.052
−
n
f
n
h
⎛
⎝
⎜
⎜
⎜
⎞
⎠
⎟
⎟
⎟
0.483
CFU
m
3
=
1000.
n
c
V
s
30