Measure and Record Ambient Temperature and Relative Humidity Simultaneously
For measuring temperature the Hi-Q Hygrothermograph employs an aged bimetal element to record temperature changes. The temperature pen arm covers a 3-1⁄8" area of the 7"H chart. The response is linear, with temperature recorded over a 110°F or 60°C span. Span is adjustable up or down to match the season (winter or summer). For measuring Humidity, a specially treated bundle of human hair is used to measure relative humidity over the full range of 0–100%. The hair expands and contracts with increasing or decreasing amounts of water vapor in the air, which is also reflected on the recording chart. Two blue felt-tip pens are provided. Charts and replacement pens are sold separately.