The new SCM3 is a standalone carbon monoxide detector (CO detector) with a very fast reaction time. Its electrochemical sensor is specific to carbon monoxide (CO). This rugged instrument can help you hunt down sources of potentially life-threatening, poisonous gas.

Carbon monoxide (CO), a product of combustion, is an odorless, colorless gas. Faulty combustion equipment is one source of this dangerous gas known as the "silent killer". The SCM3 standalone carbon monoxide detector measures CO in parts per million (ppm). Use it for walk-around tests to help pinpoint sources of CO indoors. Measure CO ppm in flue gas using the optional AOXP2.

How Does it Work?
The "Walk-Around" Test: The SCM3 responds to changes in CO levels in real time. You must find the source of CO when levels rise on entry into a structure.
  • Zero the unit outdoors away from any source of CO
  • Enter the structure
  • Walk around and watch the display
  • Move toward the area of highest concentration to find the CO source

Persistent sources of CO, such as malfunctioning combustion equipment in occupied spaces, must be serviced immediately.

Features and Benefits:
  • Fast electrochemical sensor helps you find CO sources like cracked heat exchangers or breached flue stacks
  • Calibrate to ambient quickly with ZERO button
  • Audio and visual alarms (with MUTE function)
  • Alarm rate increases as carbon monoxide concentration increases
  • MAX hold to help you zero in on the source
  • Bright-blue backlit dual-display to test in dark crawl spaces
  • Magnetic hanger for hands free testing
  • Auto Power Off (APO) to save battery life (easy to disable)
  • Battery check with % of battery life left displayed
  • Use with optional AOXP2 pump for flue gas testing
  • Intuitive interface. A fancy way of saying easy to use. Technicians take it out of the box and know how to use it before even opening the manual. (Of course, please read the two page operator's manual before use.)
  • Loud audible alarm that beeps faster as CO concentration increases
  • Rugged sensor maintains accuracy over time
  • Ruggedized body and rubber boot stands up to abuse many competitive models cannot
  • Optional AOXP2 hand pump works much better in cold weather than most electronic pumps

What's Included:
  • SCM3 Carbon Monoxide Detector (CO Detector)
  • 9V battery (installed)
  • Operator's manual

For additional technical specifications, please see "Owner's Manual & Specifications" below.
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Manuals (2)
Combustion Tool
0 to 1000PPM (2000PPM with 5 minute max exposure time)
Initial accuracy at 73°F±9°F, <75%RH:
0-15ppm ±5% reading ±1 ppm after zeroing 16-35ppm ±5% reading ±2 ppm after zeroing 36-1000ppm ±5% reading ±5ppm after zeroing
Updates real-time
CO Air Sample Temperature Range:
32 to 105°F
Operating Environment:
32 to 122ºF (0 to 50°C)
Sensor Type:
Electrochemical (specific to CO)
Sensor Calibration:
Factory calibrated on 205ppm
Long Term Drift:
<5% / year (depending on use)
Battery Type:
Battery Life:
Approx.150 hrs typical (Alkaline)
15 minutes
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