Short Term Exposure Limits (Stel Page) - MSA Altair 5X Mode D'emploi

2.4.4 Short Term Exposure Limits (STEL page)

If the STEL alarm activates, leave the contaminated area
immediately; the ambient gas concentration has reached
the preset STEL alarm level. Failure to follow this warning
will cause over-exposure to toxic gases and persons
relying on this product for their safety could sustain
serious personal injury or death.
MONOCHROME DISPLAY
STEL
This page shows the average exposure over a running 15-minute
period.
When the amount of gas detected by instrument is greater than the
STEL limit:
• Alarm sounds
• Alarm LEDs flash
• "STEL ALARM" message flashes.
To reset the STEL:
1. Access the STEL page.
2. Press the ▲ button.
The STEL alarm is calculated over a 15-minute exposure.
STEL calculation examples:
Assume the instrument has been running for at least 15 minutes:
• 15-minute exposure of 35 ppm:
(15 minutes x 35 PPM)
• 10-minute exposure of 35 ppm and
5 minute-exposure of 15 ppm:
(10 minutes x 35 PPM) + (5 minutes x 15 PPM)
This page can be de-activated through MSA Link software.
2-12
! WARNING
15 minutes
15 minutes
COLOR DISPLAY
= 35 PPM
= 25 PPM