Altair 4

This monitor is discontinued by the manufacturer.

From the Manufacturer:
MSA's new ALTAIR 4, Multigas Detector for LEL, CO, H2S, and O2 raises the standard for personal multigas detectors by offering a combination of features you won't find in competitive models.

The ALTAIR 4, Multigas Detector is the only portable gas detector with an optional MotionAlert™ feature if a user should become disabled due to unforeseen hazards. When enabled, the MotionAlert feature will activate an audible alarm if the instrument does not detect motion for 30 seconds, and is ideal for confined space entry applications. This unique gas detector function can be deactivated by the user. A high-contrast display and three large, rubberized buttons enable easy operation in low-light conditions.

The rubber over-molded housing is easy to grip, provides unsurpassed durability, is rated IP67 against dust and water ingress, and passes a 10+ foot drop test. This unit is equipped with a 95+ dB audible alarm and ultra-bright alarm LEDs on both its top and bottom for maximum visibility. Vibrating alarm and datalogging are standard features in this very competitively-priced unit.

MSA’s ALTAIR 4 Multigas Detector is Galaxy® System compatible for calibration and record keeping; a QuickCheck™ Test Station for fast, easy bump testing is also available. Data logging is a standard feature; the ALTAIR 4 Multigas Detector is MSA Link™ Software-ready.


  • MotionAlert™ feature plus audible, visual & vibrating alarms
  • InstantAlert™ feature to sound a manual alarm
  • Most rugged instrument available
  • Large buttons for easy operation
  • 16-hour battery run time when fully charged
  • Tested to IP67
  • Global approvals
  • Economically priced
  • MSA Link Software-read

Helpful Part Numbers

  • Altair 4 Charger - 10087913
  • Pelican Case for Altair 4 - 710948
  • Altair 4 Replacement Oxygen Sensor - 10089163
  • Altair 4 Replacement LEL Sensor - 10089116
  • Altair 4 Replacement COSH Sensor - 10089117
  • Altair 4 Calibration Adapter - 10089321
  • Altair 4 Front Casing/Filters - 10089162

How to Calibrate the MSA Altair 4

  1. Turn the MSA Altair 4 on in normal reading mode. Do this by pressing and holding the center button.
  2. Once the MSA Altair 4 is in normal reading mode, you need to send it into calibration mode. Do this by pressing and holding right "UP" button until it beeps at you and the screen asks you to zero the monitor.
  3. Now that the screen is asking for confirmation, press the center button once to confirm. This will send the monitor into zeroing mode. Now is a good time to set the monitor down, and grab your calibration gas, regulator, and calibration adapter.
  4. Open the valve on your regulator before attaching it to the gas cylinder. This is a very important step so you do not ruin your calibration gas cylinder. Now screw it in to your calibration gas cylinder. Close the regulator once you hear gas spewing out of it. This is the signal to know your regulator is good to close. Continue screwing in the regulator until it stops. Do not overturn it.
  5. Attach the tubing to the hose barb on your regulator. Make sure the tubing is also connected to your calibration adapter.
  6. Wait for the screen to come up asking for you to apply calibration gas. Once this screen comes up, press the center button again to confirm. Clip the calibration adapter in to your gas detector. Once it is clipped on, turn on your gas.
  7. Make sure your calibration gas values on the screen match what is on your calibration gas cylinder!
  8. Once the calibration procedure is completed, turn your gas off and remove the calibration adapter from the MSA Altair 4. The screen will go back to normal reading mode within a few seconds.
  9. Congratulations! You have officially calibrated your MSA Altair 4 gas monitor. Make sure to record these readings in your calibration log!

Standard Sensor Settings for the MSA Altair 4

Sensor Type Calibration Gas Value Low Alarm High Alarm TWA Alarm STEL Alarm Part Number
H2S - Hydrogen Sulfide 20ppm 10ppm 15ppm 10ppm 15ppm 10106725
CO - Carbon Monoxide 60ppm 25ppm 100ppm 25ppm 100ppm 10106725
LEL - Pentane Curve 58% LEL 10% LEL 20% LEL N/A N/A 10106722
O2 - Oxygen 15% O2 19.5% 23.0% N/A N/A 10106729