MSA ALTAIR 2X - Page 12

ALTAIR 2X
12
Description
GB
The device monitors gases in ambient air and in the workplace. The following
toxic gases can be monitored in the ambient air:
- Sulfur dioxide (SO
2
)
- Nitrogen dioxide (NO
2
)
- Carbon monoxide (CO)
- Hydrogen sulfide (H
2
S)
- Chlorine (Cl
2
)
- Ammonia (NH
3
)
The Two Gas (Two-Tox) sensor provides two sensing capabilities in a single
sensor. The following combinations are possible:
- Carbon monoxide/hydrogen sulfide (CO/H
2
S)
- Carbon monoxide/nitrogen dioxide (CO/NO
2
)
- Hydrogen sulfide/sulfur dioxide (H
2
S/SO
2
)
The alarm levels for the individual gases are factory-set and and cannot be
changed during operation. Changes can only be made through MSA Link soft-
ware.
Short Term Exposure Limits (STEL)
The STEL alarm is calculated over a 15 minute exposure.
STEL calculation examples:
Assume the device has been running for at least 15 minutes:
15 minute exposure of 35 ppm:
10 minute exposure of 35 ppm and 5 minutes exposure of 5 ppm:
If the device is on for longer than 15 minutes, the STEL is calculated for the most
recent fifteen minutes of runtime.
(15 minutes x 35 ppm)
= 35 ppm
15 minutes
(10 minutes x 35 ppm) + (5 minutes x 5 ppm)
= 25 ppm
15 minutes