Takes the guesswork out of heat stress calculations. This unique heat stress meter features bright, multicolor LED backlights corresponding to OSHA’s heat stress alert levels. This visual alert system not visible in outdoor daylight, allows management and workers to be instantly aware when the heat index enters potentially dangerous zones. These features, combined with the optional audible alarm help to mitigate the risk of heat-related injuries in the workplace. Calculates heat stress values for direct sunlight and shade and displays humidity, maximum and minimum ambient TA and black globe TG temperatures. Also, indicates low battery and a hold function. In order to connect this model to a computer to stream data, you will need the USB Cable #840054 and Data Acquisition Software #840052. Comes complete with clear instructions, integrated tripod screw and 4 AAA batteries. *N.I.S.T. Traceable Certification Report is available for Relative Humidity & Air Temperature functions only.Dim: 12 × 3 × 11⁄2 302 × 75 × 37 mmWeight: 11 oz 300 g *Certification Option N.I.S.T. traceable Certificate of Compliance available at additional cost Select option above. Specifications Unit of Measure Range Resolution Accuracy Ambient Air Temperature 0 to 50 degrees C32 to 122 degrees F 0.1 ±0.6 degrees C 1.5 degrees F Globe Temperature 0 to 80 degrees C32 to 176 degrees F 0.1 ±1 degrees C @15 to 40 degrees C±2 degrees C outside this range Relative Humidity 5 to 90% 0.1 ±4% WBGT 0 to 50 degrees C32 to 122 degrees F 0.1 ±1 degrees C @15 to 40 degrees C±2 degrees C outside this range Downloads Instruction Manual Product Brochure Comparison Chart Comparison Chart Videos