Investigation of the Effect of Environmental Temperatures on Non-contact Thermal Imaging for Core Body Temperature Measurement

It is difficult to assess the performance of non-contact thermometry at detection of febrile subjects unless febrile subjects are included in the test, which severely limits development and independent testing of such devices. The underlying mechanisms of non-contact thermometry might be used to develop a test without requiring the inclusion of febrile subjects, and the development and demonstration of such a test is the object of this study.

Literature review and pilot study revealed the offset between skin temperature and core (oral) body temperature is dependent on air temperature by a linear relationship. In a 70F room, the inner canthi temperature of a human with core (oral-reference) body temperature of 98.6F is 94.4F, a difference of 4.2F. This same individual in an 87F room (after waiting several minutes) will have an inner canthi temperature of 97.0F, a difference of only 1.6F (the actual values may depend on sensor confounds not addressed here). Therefore, one could use a several-minutes exposure to elevated air temperatures (equilibration environment) to simulate an elevated body temperature, by continuing to operate the device under test from a non-elevated air temperature environment (test environment), while taking care to limit the effects of temperature changes and gradients due to the mixing of these two environments.

Subjects will be recruited from a college campus via a recruitment protocol to participate in an up to 2 hour study session. The study session will involve collection of demographic information on a non-identifiable form, five collections of oral thermometry, four 10 minute periods of equilibration inside 4 elevated temperature environments during repeat continuous non-contact thermometry, and measurements via several non-contact test devices operated from within a non-elevated environment through a window into each elevated environment.