QUESTemp QT-44 Heat Stress Monitor

Area Waterless Wet Bulb Heat Stress Monitors.

The 3M™ QUESTemp° Heat Stress Monitor QT-44 offers high quality heat stress monitoring without the hassle of wet-bulb maintenance. This model measures/calculates the dry bulb, wet bulb and globe temperatures along with WBGT indoors, WBGT outdoors, relative humidity and Heat Index/Humidex.
  • Kit includes QUESTemp™ 44 unit with 2" style globe sensor and standard accessories
  • Measure/calculate dry bulb, wet bulb & globe temperature, WBGT indoor/outdoor, relative humidity and Heat Index/Humidex
  • Real time clock provides accurate reporting with time stamping
For more information on the QUESTemp QT-44 Heat Stress Monitor, contact your local Air-Met office. 
The QUESTemp° 44/46/48N utilises a waterless wet bulb sensor designed for working environments where daily instrument upkeep is difficult. A high-quality humidity sensor and proprietary algorithm perform the calculation of the WBGT values, eliminating the hassle of daily wet bulb maintenance.
The real time clock provides accurate reporting with time stamping. 
  • Utilises WBGT (Wet Bulb Globe Temperature) sensing technology; the standard for heat stress management
  • Waterless wet bulb sensing technology eliminates daily maintenance
  • Convenient stay time parameters per multiple standards help determine work/rest ratios
  • IP 54 ingress rating helps protect unit from exposure to dirt, dust, oil and water 
  • Designed to withstand the rigors of everyday use in  demanding environments
 Natural Wet Bulb ModelsWaterless Wet Bulb Models
Measurement Parameters: QT°32 QT°34 QT°36 QT°44 QT°46 QT°48N
Dry Bulb, Wet Bulb and Globe Temperatures, Relative Humidity
Air Velocity     option   option  
WBGT (indoor) Index  
WBGT (outdoor) Index
Heat Index/ HUMIDEX  
Temperature Reading: Celsius or Fahrenheit
Data Logging Intervals: 1, 2, 5, 10, 15, 30 or 60 minutes  
Event Logging Mode          
Display Languages: Choose from Chinese, Czech, English, French, German,
Italian, Japanese, Korean, Norwegian, Polish, Portuguese, Russian, Spanish, Swedish,
and Turkish
Time & Date Stamping with Clock and Calendar  
Displayed Stay Times: ACGIH TLV, U.S. Navy PHEL charts, U.S. Navy/Marine Corp. Ashore Flag Conditions, EPRI Action Limits (QT°48N excludes EPRI)      
Head-Torso-Ankle Weighted Average WBGT (optional with tri-sensors) option option option option option  
Dry Bulb Sensor - 1000 Ohm platinum RTD
Accuracy and Ranges: +/-0.5 from 0° C to 120° C (+/-0.9° F from 32° F to 248° F)
Wet Bulb Sensor - 1000 Ohm platinum RTD
Accuracy and Ranges: +/-0.5 from 0° C to 120° C (+/-0.9° F from 32° F to 248° F)
Waterless Wet Bulb (Humidity) sensor
Accuracy and Ranges: +/-1.1° C (k=2) between 0° C and 80° C (32° F and 176° F)
Globe Sensor - 1000 Ohm platinum RTD
Accuracy and Ranges: +/-0.5 from 0° C to 120° C (+/-0.9° F from 32° F to 248° F)
Relative Humidity Sensor
Accuracy and Ranges: +/-5% from 20 to 95% (non-condensing)
Air Velocity Probe - Omni-directional heated thermistor
Accuracy and Ranges: +/-(0.1 m/s + 4%) from 0 to 20 m/s
    option   option  
Operating Temperature Range:            
Sensor Assembly: -5° C to 100° C (23° F to 212° F)
Electronics: -5° C to 60° C (23° F to 140° F)
Data Management:            
Detection Management Software DMS
Thermal Comfort Indices in Accordance with ISO 7730
Predicted Mean Vote (PMV) and Predicted Percent Dissatisfied (PPD)
    option   option  
Output: RS-232 Serial Printer / Computer Interface; Parallel Printer Interface  
Power Source:            
9V Disposable Batteries; Hours of Battery Life 140 80
NiMH Rechargeable Battery; Hours of Battery Life 300 160
D-ring with Lanyard Attachment. Allows for Hands-Free Monitoring
Tripod Mount / Remote Sensor Bar.
Allows for up to 61 m (~200 ft) Long Distance Measurement
IP54 Water & Dust Ingress Protection Rating
Case Size (including mounted sensor assembly) 23.4 x 18.3 x 7.6 cm (9.2" x 7.2" x 3")
Weight: 1.2 kg (2.6 lb) with Mounted Sensor Assembly
Standards and Approvals: Intrinsic Safety, UL/CSA standards for Class I groups A, B, C & D,
Class II groups E, F & G, Class III temperature code T3 & ATEX
Electromagnetic Conformance: CE Mark

  • Health and safety testing
  • Military training facilities
  • Athletic training & events facilities
  • Warehousing & distribution centres
  • Manufacturing plants
  • Nuclear & fossil fuel power generation plants
  • Shipbuilding operations
  • Occupational heat stress management
  • Indoor air quality investigations
  • Thermal comfort monitoring
  • Risk analysis of job function or activity