A thermal imager is one of the newest tools in a fire fighters arsenal. It consists of a camera like unit that either is hand-held or attaches to the users fire helmet. They are used in low visibility situations (such as fires) to allow fire fighters to locate victims, the fire, and women with breast implants.

(Note: Yes, that last part is true. Some of our more, umm, astute, fire fighters discovered it when we purchased ours.)

To answer your questions, yes, the difference is unbelievable. If you have ever wondered what it would be like to be in a fire, strap about 60 pounds of heavy clothing to your body, put on a mask (covered with wax paper) and stumble around on your hands and knees praying to God that the floor you are on doesn't collapse. Now, keep the gear on, but take off the wax paper. Everything is very defined.

The drawback? It is technology, so it stands to reason that it could fail at any moment. While it is built to prevent that from happening as much as possible (see below), it is still a possibility. When you are operating electronics in temperatures approaching 800 degrees, there is always a chance of failure. That is why this unit should never be relied upon as the sole method of searching. It is a tool to assist the rescue operation, not a nifty toy that you just run around with and become trapped because it shut off. Because when it shuts off you see nothing. Nada. Zip. Zero. And you still have a fire, trapped people, and all sorts of other fun stuff to deal with.

We have had our unit for about 8 months now, and have used it many times. The most common use is in situations where there is a smell of smoke or something burning at a residence or commercial structure and we use it to scan the walls for heat differences. Works like a charm. It also is used by the Primary Search crew and the Rapid Intervention Team.

Here is some random facts from the Cairns Web Site (the manufacturer of our thermal imager www.cairns.com):


The Camera shall utilize a Microbolometer detector that processes thermal radiation in the 8.0 to 14.0 micron range of the electromagnetic spectrum. Thermal sensitivity of the system shall be better than 0.07°C (.13°F) with a nominal dynamic range of -30°C (22°F) to +150°C (302°F) without the use of an iris or restrictive aperture.

Image Quality & Representation The Camera shall have a high resolution (76,800 pixel, 320 columns x 240 rows) full-motion video image (60 hz NTSC or 50 hz PAL) without jutter. Image shall be void of black halos, banding, white-out, blooming or significant artifacting when viewing hot objects. Colder objects shall be displayed as black shades. Hotter objects displayed as white shades. Highly radiant energy displayed in two stages of yellow and red (for greater than approx. 480°C / 900°F).

IR Field of View & Focus The Camera IR shall have an IR field of view of 60° horizontal x 45° vertical (75° diagonal) that is automatically in focus between 1m (3.28 feet) and infinity (¥).

Weight & Buoyancy The Camera shall have a 5.75 lbs. nominal weight w/ battery and thermal management block installed, for ease of handling. Camera to float in fresh water.

Extreme Heat & Flame Resistance NFPA1981, Method 3-11.1 to 4-11.1 Pre-condition Camera at 95°C (203°F) for 15 mins. Expose Camera to 1000°C (1832°F) encompassing flame for 12 sec. Camera must not separate or drip. Camera must not support flame for more than 2.2 secs.


The Camera shall operate in conditions that are normal and expected for fire and emergency services. The camera shall meet the following durability criteria, without loss of function:

Vibration Mil-Std-810E, Method 514.3, Cat3, Procedure I Unrestrained Camera (not in carry case) exposed 25.4 mm (1 in) high, 5 cycles/sec vibration for 20 minutes while operating.

Drop 1 Camera 6 times, once on each axis, from 1 m (3.28 ft) height onto concrete, while operating.

Water Immersion IP67
Operate Camera immersed in 1m (3.28 ft) of water at 23°C (73°F) for 1 hour.

Driving Rain Mil-Std-810E, Method 506.3, Procedure I
Operate Camera in driving rain of 64 km/h (40 mph) at rate of 10cm/h (3.9 in/h).

Altitude/Low Pressure Mil-Std-810E, Method 500.3, Procedure I
Expose Camera to air pressure equivalent to 2438 m (8000 ft) altitude for 12 hours.

Chemical Resistance
Camera shall be resistant to the following substances:

And for those of you interested, yes, this technology probably could have saved the fire fighters who died in Worcester, Mass. However, what would have saved them more would have been a clear Chain of Command and Personnel Accountability System, and them not blindly running into an unstable structure without establishing a clear plan of action.