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Model AQH-20 Handheld Indoor Air Quality Meter

Measures CO2, Temperature and Humidity

The Model AQH-20 Indoor Air Quality Meter reduces the number of instruments a contractor has to carry by measuring the carbon dioxide concentration, air temperature, and humidity percentage in one device. A large backlit LCD display shows all three parameters simultaneously. The Model AQH-20 can display dew point or wet bulb temperatures in place of the ambient temperature. Minimum, maximum, and average readings are easily accessible through the function buttons. By pressing the hold key, the current values are held so that they can be recorded. An audible alarm warns the user that the current ambient conditions are becoming hazardous. The Model AQH-20 includes a hard carrying case and batteries.

Models & Ordering

Model Description Usually Ships Price Order
Ships: Next Day>
Price: $225.00
Handheld indoor air quality meter. Next Day $225.00 Order


CO2: 0 to 2000; Temperature: 14 to 140°F (-10 to 60°C); Relative Humidity: 0.0 to 99.9% RH.
CO2: ±30 ppm ±5% of reading; Temperature: ±0.9°F (±0.6°C); Humidity: ±3% RH (10 to 90%), ±5% (0.0 to 9.9% or 90 to 99.9%).
CO2: 1 ppm; Temperature: 0.1°F (0.1°C); Humidity: 0.1% RH.
Response Time:
CO2: < 30 seconds; Temperature: < 2 minutes; Humidity: <10 minutes.
4 digits for temperature/CO2 and 3 digits for humidity.
CO2 Sensor:
Non-dispersive infrared.
Temperature Limits:
32 to 122°F (0 to 50°C).
Humidity Limits (Non-Condensing):
0 to 95% RH.
Power Requirements:
(4) 1.5 V AA alkaline batteries, included, user replaceable.
Warm Up Time:
30 seconds.
6.76 oz (200 g).
Agency Approvals:


Model Number Description Usually Ships Price Order
33% and 75% Salt Bath Calibration Standards. TH-CAL 33% and 75% Salt Bath Calibration Standards. Next Day $115.00 Order

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