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Measurements
Measurements
WetBulb Globe Temperature (WBGT)
Measurements
The QUESTemp° 48N data logging, with an event logging mode, heat stress monitor directly senses three parameters: dry bulb temperature (DB), globe temperature (G), and relative humidity (RH).
It computes the Wet Bulb (WB), the Wet Bulb Globe Temperature (WBGT), and the Stay Times Indices for ACGIH, U.S. Navy PHEL charts, and Flag Conditions for U.S. Navy/Marine Corp. Ashore.
WetBulb Globe Temperature (WBGT)
The WBGT is a type of temperature index which combines the effects of temperature, humidity, radiant heat, and air flow and provides a relatively simplistic tool to analyze thermal comfort. The resulting WBGT values can then be compared to indices of
The WBGT calculation is a weighted average of the three temperature sensors using the following formulas:
**NOTE: Navy and Marine calculations are all based on the outdoor computation.
∙WBGT (outdoor) = 0.7WB + 0.2G + 0.1DB (denoted as “WBGT” on the display)
Stay Times/Rest Times (Indicies)
Stay Times Indices represent how long a worker should be able to safely work under heat stress conditions. Select one of four indices for displaying and printing from the unit: ACGIH Stay Times, NAVY PHEL’s, or Flag Conditions for U.S. Navy/Marine Corp. Ashore. Refer to Appendix B for more information on the indices. NOTE: it will appear as “Index” on the measurement screen.
Remote measurements
The top sensor bar may be removed from the instrument and used through a remote cable. (Please refer to Appendix C for remote cable options.) Shelter the instrument and remote the sensor bar if the measured environment is expecting heavy rain or if temperatures are above 60°C.