EXTECH FM200 Formaldehyde (CH2O or HCHO) Meter

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The Extech FM200 measures Formaldehyde concentration, Air Temperature, and Humidity. Adjustable audible alarm feature is excellent for checking indoor air quality in buildings.

Formaldehyde is used in the manufacture of many industrial and consumer goods. Emissions from some of these items can rise when moisture and heat increase. These emissions are a contributing factor to Sick Building Syndrome, which may lead to itchy eyes and throat, as well as headaches and dizziness.

  • Glue/Paint manufacturers
  • Insulation/Plywood/Fiberboard
  • Timber Paneling/Particleboard
  • Cosmetics
  • Shampoos
  • Soap Bars/Body Wash

Authorised Australian Distributor

CE   1 Year

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SKU: EXTECH FM200 Categories: , , Tags: ,

The Extech FM200 measures Formaldehyde CH2O (HCHO) concentration, Air Temperature, and Relative Humidity. The alarm feature alerts the user when the Formaldehyde 0.08ppm limit is exceeded.   This device is shipped fully tested and calibrated and, with proper use, will provide years of reliable service. Please visit our website (www.extech.com) to check for the latest version of this User Guide, Product Updates,

EXTECH FM200 Features:

  • FM200 is a handheld Formaldehyde Meter with Detachable Probe
  • Simultaneously displays Formaldehyde concentration, Air Temperature, and Relative Humidity readings on large LCD with backlight feature
  • Audible alarm default at 0.08ppm (adjustable)
  • Designed with Electrochemical CH2O sensor
  • Sensor LED indication where green indicates sensor is connected properly and power is on, red LED shows the fan is in working condition (active = flashing red; inactive = solid red)
  • Built-in bumper that allows the fan inside the sensor to draw in gas quickly
  • CH2O Calibration function in fresh air
  • Min/Max and Data Hold
  • Auto power off with disable
  • Low battery indicator
  • Complete with soft tube (approx. 300mm), sensor with 655mm cable, 6 AAA batteries and carrying case


Specifications Range Resolution Basic Accuracy
Formaldehyde (CH2O or HCHO) 0.00 to 5.00ppm 0.01ppm ±5%
Air Temperature 32 to 122°F (0 to 50°C) 0.1°F/°C ±2°F/1°C
Relative Humidity 10% to 90%RH 0.1%RH ±5%RH
Dimensions 160 x 60 x 40mm)
Weight 181.4g)

Low Battery

When the battery icon appears on the LCD, the batteries must be replaced. In a downward motion, slide the rear battery compartment cover off of the meter housing. Remove the old batteries and replace with new batteries (all of the same type) observing correct polarity. This meter uses six (6) 1.5V AAA batteries.

Battery Safety Reminders

  • Please dispose of batteries responsibly; observe local, state, and national regulations.
  • Never dispose of batteries in a fire; batteries may explode or leak.
  • Never mix battery types; install new batteries of the same type.

Error Display Codes

The following errors may appear on the FM200.

ERR‐1: Temperature or humidity sensor is damaged or sensor communication error

ERR‐2: HCHO, Temperature, or humidity readings are out of range If the sensor is subjected to a high concentration of HCHO or other sensitive chemicals listed in the Sensor Cross Sensitivity table, it will read ERR2. Let the sensor run for a few hours in clean air and the meter will read normal again