MSA ALTAIR io 4 User Manual

Alarm Types Description
Evacuation Alarm remotely activated from Grid.
Motion Detection - No Check-In Motion Detection Check-In not acknowledged.
Maintenance Alarms
Critical Battery Level Battery level has less than 10 minutes remaining.
Sensor Error Sensor is not properly installed or is not functional.
4.2 Gas Detection
4.2.1 Time-Weighted Average (TWA)
The device can monitor the time-weighted average (TWA) of exposure to toxic gases which calculates the average
exposure since the device was turned on or since the TWA calculation was reset.
The current TWA exposure calculation can be viewed and reset through the device menu and can be configured through
Grid to calculate using two different methods: Rolling Window and Cumulative Average.
NOTE: Power cycling the device will reset the time-weighted average calculation
Rolling Window
When Rolling Window is selected, the TWA is calculated based off the exposure during most recent configured shift length.
This is OSHA’s typically recommended TWA calculation.
Example Calculation
• Device powered on for 12 hours
• 4 hours of exposure at 50 ppm in hours 0 – 4
• 4 hours of exposure of 0 ppm in hours 4 - 8
• 4 hours of exposure at 50 ppm in hours 8 – 12
• 8 hour shift length selected
Cumulative Average
When cumulative average is selected, the TWA is calculated based off the exposure during the entire time the device has
been on without power cycling while dividing by the configured shift length, regardless of how long the device is powered on.
This is the ACGIH / EH40 typically recommended TWA calculation.
Example Calculation
• Device powered on for 12 hours
• 4 hours of exposure at 50 ppm in hours 0 – 4
• 4 hours of exposure of 0 ppm in hours 4 - 8
29 ALTAIR io 4
US 4 Features

MSA ALTAIR io 4 Specifications

General

Brand	MSA
Model	ALTAIR io 4
Category	Gas Detectors
Language	English