Monitoring The Oxygen Concentration - MSA ALTAIR 4 Operating Manual

DESCRIPTION
2.6

Monitoring the Oxygen Concentration

The instrument monitors the oxygen concentration in ambient air. The alarm
set points can be set to activate on two different conditions:
• Enriched - oxygen concentration > 20.8 % or
Deficient - oxygen concentration < 19.5 %.
•
While the instrument can detect up to 25% oxygen in the ambient air, it is
approved for use only up to 21% oxygen-content.
If an alarm activates while using the instrument, leave the area
immediately.
Remaining on site under such circumstances can cause serious
personal injury or death.
When the alarm set point is reached for either of the above conditions:
an alarm sounds
•
alarm LEDs flash
•
• a vibrating alarm triggers
• instrument displays and flashes the Alarm icon
Minimum icon
(Deficient alarm) along with the corresponding oxygen
concentration.
The LOW alarm (oxygen deficient) is latching and will not automatically
reset when the O concentration rises above the LOW set point. To reset
2
the alarm press the [
button only silences the alarm for five seconds.
False oxygen alarms can occur due to changes in barometric pressure
(altitude) or extreme changes in ambient temperature.
It is recommended that an oxygen calibration be performed at the
temperature and pressure of use. Be sure that the instrument is in known
fresh air before performing a calibration.
20
WARNING
(Enriched alarm) or the Maximum icon
] button. If the alarm condition still exists, the [
ALTAIR 4 - Operating Manual
MSA
and either the
]