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1 Introduction
Introduction
Up and Running overview
Introduction
The new heat stress instruments, the QUESTempº 44 and QUESTempº 46, offer traditional heat stress monitoring without the aggravation of maintaining a wet bulb. Through collaboration with Professor Dr. Thomas Bernard, from the College of Public Health at the University of South Florida, mathematical models were implemented to create a Waterless Wet Bulb calculation through a combination of dry bulb temperature, globe temperature, relative humidity, and air flow. The Waterless Wet Bulb is used to calculate the Wet Bulb Globe Temperature (WBGT) which is a widely- used method to monitor environmental conditions related to heat stress.
Figure 1-1: QUESTempº 44/46 in a thermal environment
QUESTempº Models
QUESTempº 44 and QUESTempº 46 both measure and calculate the dry bulb, wet bulb, globe, WBGT indoors, WBGT outdoors, relative humidity, and Heat Index or Humidex.
With the QUESTempº 46, you have the capability to measure stay times in order to manage work/rest regimens. Guidance is based on the screening criteria for heat stress as defined in the ACHIH TLV Handbook, U.S. Navy PHEL charts, U.S. Navy/Marine Corp. Ashore Flag system, and EPRI Action Limits.
An additional feature with the QUESTempº 46 is an optional detachable probe for measuring air velocity to determine appropriate levels of indoor thermal comfort monitoring.