MSA ORION - Warning

To Reset the TWA:
1. Access the TWA page.
2. Press and hold the CHANGE/RESET button until the TWA
flag flashes.
3. Push the ON-OFF/PAGE button to reset the TWA.
The TWA alarm is calculated over an eight-hour exposure.
Calculation examples are as follows:
•
1-hour exposure of 50 PPM:
(
1
hour x
50
PPM
) + (
7
ho urs x
0
PPM
)
8
ho urs
=
6.25
PPM
•
4-hour exposure of 50 PPM
4-hour exposure of 100 PPM:
(
4
hours x
50
PPM
) + (
4
ho urs x
100
PPM
)
8
ho urs
=
75
PPM
•
12-hour exposure of 100 PPM:
(
12
ho urs x
100
PPM
)
8
ho urs
=
150
PPM
NOT E:
The accumulated reading is always divided by
eight hours.
º
WARNING
If the TWA alarm condition is reached while using the
instrument as a personal or area monitor, leave the
contaminated area immediately; the ambient gas
concentration has reached the preset TWA alarm level.
Failure to follow this warning will cause over-exposure to
toxic gases, which can result in serious personal injury or
death.
Chapter 3, Using the Orion Multigas Detector Operating Manual
3-16