Ion Science MiniPID - Manual (Page 21)

MINIPID 3PIN MANUAL Ion Science Ltd
Page 21 of 27
Unrivalled Detection. www.ionscience.com
Environmental Effects
Natural physical effects of humidity
Water is not itself detected by MiniPID, but it adsorbs a portion of the light that otherwise promotes a
response from a photoionisable gas.
The response of the MiniPID to humidity can be adjusted according to the figures presented below, for
Fahrenheit and Celsius temperatures. For example, it can be seen that at 80
o
F and 90% relative humidity
(RH), a response is decreased from that in dry air by 20%. This effect will be the same for any detectable
gas.
90
91
92
93
94
95
96
97
98
99
100
0 20 40 60 80 100
p
er
ce
n
tage
o
f r
es
p
o
n
se
v
s.
RH
=
0%
relative humidity, RH%
30 ºF
50 ºF
70 ºF
80 ºF
90 ºF
100 ºF
90
91
92
93
94
95
96
97
98
99
100
0 20 40 60 80 100
p
er
ce
n
tage
o
f r
es
p
o
n
se
v
s.
RH
=
0%
relative humidity, RH%
30 ºC
40 ºC
20 ºC
10 ºC