Ministry of Defense

The risk of heat injury to soldiers is a concern within the Defense training centers. The distances, gear, and the outside temperature are factors that cannot be influenced. Evalan’s team was asked to help develop an accurate and reliable heat monitoring solution. The result: ARMOR Heat Monitor. ARMOR Heat Monitor monitors the core body temperature during a training routine and helps military trainers and recruits detect heat stress on time.
ARMOR sensor
ARMOR heat monitor

The problem

Heat stress is a significant problem among soldiers. Heavy gear, protective clothing, and strenuous physical exertion cause the core body temperature to rise sharply. The consequences of this can be serious: think of disorientation, loss of consciousness, or seizures. These heat-related injuries can lead to permanent health damage and even death. Therefore, Evalan was asked to develop an accurate and reliable heat monitoring solution. The result: ARMOR Heat Monitor.

ARMOR consists of a heart rate sensor, the ARMOR device and ARMOR app. From the heart rate data, the core body temperature of each soldier is estimated and this information is sent to the app. The app provides an overview with details of all participants. For each participant, the current estimated core body temperature is displayed, as well as the physiological strain index (PSI). The PSI is a rating of the relative heat strain on a scale of 1 to 12.As soon as the heat strain of a participant is too high, the app will sound an alarm. The supervisor can then intervene immediately and initiate actions according to a defined protocol.

The device helps to identify the first indications that cause heat stress and serves as an incentive for a medical check to prevent this.

  • Accurately collects heart rate data and estimates the core body temperature
  • Helps to identify an increased risk of heat-related injury
  • A comfortable and non-invasive way of monitoring heat stress
  • Clear overview with the PSI score of each soldier

Extra details

ECTemp algorithm

The ARMOR Heat Monitor measures the heart rate with a standard Bluetooth sensor. The data is processed with the patented ECTemp algorithm, resulting in an accurate estimate of core body temperature. This integrated ECTemp algorithm used to estimate core body temperature is developed by the United States Army Research Division (USARIEM) and has been extensively tested for accuracy. It is used for ARMOR Heat Monitor under license.

The ARMOR app displays the current estimated core body temperature is displayed, as well as the PSI. The app identifies the risks to the participants using a color scheme (green, orange, red) that can be customized by the supervisor.

The ARMOR heat monitor has been tested in various training situations by the Dutch army. Now, more than 1,000 ARMOR Heat Monitor systems are in use at Defense training centers in the Netherlands.




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