| HYGROTHERMOMETER | These little hand held devices can be useful for a quick check of temperature and relative humidity, and they will even record maximum and minimum values over a period of time. In a disaster situation, a few of these meters could be used to quickly obtain an assessment of the environmental conditions for a large area. However, they tend to be rather inaccurate for reading the relative humidity in the higher and lower ranges and should never be used to calibrate any of the permanent monitoring devices. |