Calculation of the BTPS factor:
VolumeBTPS = VolumeATPS x BTPS factor
Where: PB is the barometric pressure
is
water vapour partial pressure at room temperature
is
water vapour partial pressure at body temperature (see value in the table below)
is
body temperature
is
room temperature
|
The Water Vapour Tension at Various Temperatures |
|||||||||
|
toC |
I8 |
20 |
22 |
24 |
26 |
28 |
35 |
37 |
38 |
|
Pt(H2O)mmHg |
I5.5 |
17.5 |
20 |
22 |
25 |
28 |
42 |
47 |
49.5 |
|
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