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Thermal Imaging System for Human Fever Screening

Fever Threshold

Fever threshold is the temperature threshold, often 38°C (100.4°F), used by medical practitioners to indicate a fever when using a medical thermometer. However, studies indicate that the threshold for a fever can vary depending on a number of factors such as age, gender, time of day, activity level, and clothing. For this reason, the threshold for a fever should be determined based on the characteristic of specific subject groups.

Adjusting Fever Threshold

Fever threshold may need to be adjusted periodically in order to minimize the number of missed detections or false violations. The figure below shows the internal core temperature distribution for both healthy and febrile individuals and illustrates how fever threshold can affect the number of missed detections and false violations.

Lowering fever threshold (moving the vertical line to the left) will reduce the number of missed detections, but will increase false violations. Increasing fever threshold (moving the vertical line to the right) will reduce false violations, but will increase missed detections. In other words, if your priority is to minimize the number of potentially feverish subjects that are not detected, fever threshold should be lowered. This will however, result in a higher false violation rate. On the other hand, if your priority is to minimize the number of false violations, fever threshold should be increased. This will however, increase the number of missed detections.

The value of fever threshold depends on the specific requirements of your particular fever screening operation. For example, many hospitals are able to conduct more thorough fever screening evaluations because they have sufficient personnel available to handle large numbers of false violations. Hospitals, therefore, would typically set fever threshold lower in order to minimize missed detections. In contrast, fever screening operations at many businesses and manufacturing facilities are conducted by a limited number of health or security personnel and may set fever threshold higher in order to minimize the number of false violations.

This product is currently for export only. Optotherm is currently undergoing the US FDA Premarket Notification (510k) submission process for medical devices. As soon as Thermoscreen has been cleared, this product will be available for purchase in the US.

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