The Measurement of core body temperature is carried out routinely in hospitals, as well as many other areas, such as competitive sports and in sleep labs. However, this is generally carried out as an individual measurement. The accuracy of these individual measurements is typically quite limited, for the following 3 reasons:

• the accuracy of the measurement instrument itself is often crude (the device is often not accurate to within a range of 0.5°C)
• The place of measurement is not ideal, being typically too peripheral to be reliable (forehead, armpit, mouth, rectum). More suitable measurement areas include the ear, oesophagus, major arteries, and the heart.
• Insufficient experience of the person taking the measurements can significantly reduce their accuracy.

Core body temperature is connected with many mechanical, biological, biochemical and even mental processes. This means that it is very difficult to attain a clear relationship between core body temperature and these proceses. Thus it becomes all the more important to measure core body temperature continuously, as opposed to single-shot, if one wants to gain a better understanding of these complex interrelationships.

This is not surprising, as body core temperature is influenced in complex ways to a lot of biological processes in the body as well as to other values. Therefore, it is very difficult to identify exactly one parameter contributing to body temperature, particularly if only discontinuous measurements are carried out.

Thus there is a pressing need to be able to continuously monitor the body core temperature, especially during everyday life. This will enable us to comprehend the factors and their interrelations which influence it.

Continuous monitoring of any given physical parameter requires the development of a mobile sensor. Only a mobile sensor can deliver uninterrupted measurement under normal everyday life conditions. A mobile sensor adds an extra problem of measuring accuracy, due to the introduction of motion artefacts. This sensor must control for these sources of noise, as well as the other known sources of noise which affect ordinary non-mobile sensors.

The mobile temperature sensor of BLM exactly meets these criteria. The sensor is very small, unobtrusive and easy to carry, at the same time providingextremely precise continuous monitoring of temperature. Even the slightest temperature variations, e.g. originating from small strains such as climbing the stairs, are recognized and recorded.

Thus it is possible for the first time to measure the body core temperature continuously. With this measuring method, numerous different tests can be carried out to improve the understanding of the numerous interrelations which influence body temperature.

As can be seen, (albeit just barely!) in the photo below, the temperature sensor is nearly invisible during use.