Kestrel 5400

The Kestrel 5400 is revolutionary in size, cost, and capability for those in need of measuring Heat Stress. Available with or without LiNK (Bluetooth) and/or a compass.

Along with having a Wet Bulb Global Temperature reading, the Kestrel 5400 displays thermal work limit (“TWL”), another recognized composite heat stress prediction tool. For both WBGT and TWL, the Kestrel 5400 provides on-screen alarms when conditions enter the caution and danger zones, providing clear and immediate guidance that heat illness prevention steps must be taken. Clothing levels can also be customized, making the Kestrel 4400 particularly useful in activities requiring heavy protective gear which worsens heat stress. The Kestrel 5400 also displays natural wet bulb temperature and black globe temperature.

The Kestrel 5400 uses a 1-inch black globe to gather information about the environment, which isn't possible with current Kestrels. As is true with the original Wet Bulb Globe Temperature apparatus, a temperature sensor is installed inside the globe that will measure the temperature inside. The temperature inside the globe is a function of the ambient air temperature, solar insolation, and wind speed.

As one can imagine, a sunny day will make the globe hotter because it's painted black, and colder ambient temperatures will have a tendency to cool off the globe. Lastly, the wind will cause the globe to get closer to the ambient air temperature because it will carry heat away from the globe when the air is cooler, or increase heat transfer to the globe if the air is warmer than the globe.

The Kestrel must sit out for a period of time to allow the globe to adjust to true atmospheric conditions; we recommend a minimum of 7-10 minutes. The globe temperature is then taken into account along with other measurements, such as ambient temperature, humidity, and pressure, to calculate more meaningful measurements, such as Wet Bulb Globe Temperature and Thermal Work Limit.

Features
Specifications
Accessories
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Features

Wet Bulb Globe Temperature ("WBGT")
Thermal Work Limit ("TWL")
Waterless! Natural Wet Bulb Temperature accurately calculated from onboard digital sensors with no tedious setup or maintenance.
Large, hi-res, hi-contrast, graphics display is perfectly readable in the brightest sunlight and is backlit for use in low-light conditions.
Globe Temperature
Naturally Aspirated
Wet Bulb
Temperature
Wind Speed (Current, Average, & Maximum)
Altitude
Barometric pressure
Relative humidity in %
Heat stress index
Dewpoint
Wet bulb temperature
Density
Pressure trend
Wind chill
Air, water, and snow temperature °F or °C
Waterproof and floats
Time and date
Easy-to-read backlit display
Data Logger (automatic and manual)
Customizable data storage - 2900 data points
Humidity sensor can be calibrated in the field with our Relative Humidity Calibration Kit
Customize screens to display user-selected measurements
Graph and recall trends
User-replaceable impeller
Data charting & Upload to a computer (with optional interface)
IP-67 sealed to exclude dust and water at 3 ft. submersion
Meets MIL-STD-810F 516.5 Procedure IV Transit Shock test - 20 drops from 5 ft