Exposure to extreme heat can cause heat stress, which can result in heat illnesses and injuries like heat stroke, heat exhaustion, heat cramps, or heat rashes. Both workers and athletes who are exposed to extreme heat, while working or practicing in hot environments may be at risk of heat stress or even deaths from heat exposure. Military training units struggle to keep soldiers healthy while preparing them for the grueling heat of Iraq and Afghanistan. In every instance, the accurate and localized measurement of heat stress conditions is a key component of a heat illness prevention plan. The Kestrel 5400 Waterless WBGT Heat Stress Tracker perfectly answers this problem.
The Kestrel 5400 is revolutionary in size, cost, and capability for those in need of measuring Heat Stress. It’s available with or without LiNK (Bluetooth) and / or a compass. Coaches, supervisors and event organizers get critical information and alert to make timely decisions and prevent heat-related injuries and incidents. It’s slightly bigger and more robust than the previous models, but there isn’t a noticeable difference. It now comes with a slightly larger and improved higher contrast, providing better screen resolution under any lighting (even sunlight), making it easier for your eyes to read. The new 5400 model is now capable of producing around 10,000 data points, while the 4000 series only had under 5000 data points. It comes with a carrying pouch, a lanyard, one AA battery, and a Vane Mount.
Human heat stress results from a combination of many environmental factors – air temperature and humidity along with radiant heat from the sun and surfaces, balanced by the cooling effect of breezes or airflow. The most common composite measurement used to determine appropriate exposure to heat stress conditions is Wet Bulb Globe Temperature or “WBGT.” The American College of Sports Medicine, the American Conference of Governmental Industrial Hygienists, and the US Military all have published threshold limit values (TLV’s) or reference guidelines for conditions, activity levels and hydration based on WBGT, clothing levels and acclimatization of participants.
Along with having a WBGT Heat Stress Meter Line for Wet Bulb Global Temperature reading that helps to prevent heat stress related injuries or illnesses, 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 5400 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.
As for weather reading features, they’re the same. You won’t get a “better” temperature reading, wind reading, etc, or even more readings than the ones available on previous models (4400/4600), but there are still some pretty outstanding updates. The Kestrel 5400 features flag warnings via loud buzzer & LED beacon, which works in multiple languages (English, French, German, Spanish), and offers users an intuitive user-interface screen navigation. It’s equipped with a scratch and breakage-resistant window and is rated IP67-waterproof. The 5000 series include both options of Red (NV – Night Vision) & White backlights.
Regarding its connectivity, it features Bluetooth LINK and works with PC and Mac via Dongle, as well as Android and IOS Smartphones. Regarding its battery, the battery door is located in the back, sealed away from the motherboard in case your battery leaks, like it occasionally did with all previous 4000 series. All 5000 models’ battery doors are the same and interchangeable. It only takes 1 AA battery instead of 2 AAA.
The Kestrel Waterless WBGT 5400 Heat Stress Tracker still features the same quality USA made meter, backed by a 5-year warranty. It’s currently available for between $480-$600, depending on if you get it with or without LiNK (Bluetooth), and / or a compass. There’s also the option of a Tripod. You can find the Kestrel 5400 on Kestrel’s official website, here.