The Truth Behind Temperature Sensing — Part 2

Last month, we opened the discussion on temperature sensing with your thermal imager. As a quick review, the actual name for temperature sensing is radiometry. Temperature sensing is a generic term used by the fire service referring to the ability of a...


type='node' cid='351817' />Last month, we opened the discussion on temperature sensing with your thermal imager. As a quick review, the actual name for temperature sensing is radiometry. Temperature sensing is a generic term used by the fire service referring to the ability of a thermal imager to...


To access the remainder of this piece of premium content, you must be registered with Firehouse. Already have an account? Login

Register in seconds by connecting with your preferred Social Network.

OR

Complete the registration form.

Required
Required
Required
Required
Required
Required
Required
Required
Required
Required

A decent amount of training on these concepts can be conducted right at the stove in the firehouse. If you have a gas stove, you can readily show that temperature sensing will not account for air temperature by turning the burner on high and positioning the imager low to the burner so that the crosshairs are looking through the flame. The flames themselves will have little effect on the temperature measurement, but if you place a cast-iron skillet on the flame, the skillet will provide a measurable surface.

If you have an electric stove, cover half of the burner with aluminum foil with the more reflective side out, then turn the burner on. After several minutes, you will get a dramatically different temperature reading from the uncovered side than you do from the covered side as seen in the two images on page 44 The aluminum foil is in direct contact with the burner and must be as hot as the burner, yet it displays dramatically differently. This is obviously due to the reflectivity of the aluminum foil.

Another scenario would be to place a small space heater approximately 18 inches behind a closed door and wait several minutes. You can then use the thermal imager to locate temperature differences in different areas of the same door and use that information to direct investigative efforts.

The bottom line to all of this temperature sensing is this: never attempt to replace basic firefighting skills with a thermal imager. If you find yourself crawling down a hallway at 2 A.M. and you are on your belly due to the heat conditions, but you look at the temperature display of your thermal imager and it indicates a temperature of 200°F, don't go back to crawling on your hands and knees.

Temperature sensing is not nearly as accurate as a well-trained firefighter. Always trust training. You can enhance training with thermal imaging, but you can never replace training with a thermal imager.

BRAD HARVEY is the Thermal Imaging Product Manager at Bullard. He is a veteran of public safety as a firefighter, police officer and paramedic and is certified through the Law Enforcement Thermographers' Association (LETA) as a thermal imaging instructor. Harvey has worked as a high-angle rescue instructor and is a certified rescue technician and fire instructor. If you have questions about thermal imaging, you may e-mail him at brad_harvey@bullard.com.