A decade ago, only a few well-funded and progressive fire departments owned a thermal imager. That has changed significantly. According to a study by the National Institute of Standards and Technology, an estimated 63% of fire departments serving populations of more than 10,000 have at least one thermal imager; of those that don't have one, 72% plan to acquire at least one in the next five years.

So what are fire departments looking for? In June 2005, NIST published the results of a workshop designed to determine thermal imaging needs of first responders. The organization worked with manufacturers and training experts, members of the fire service, and other fire professionals. The outcome was very simple and expected. First responders want a thermal camera to be small, lightweight, reliable, rugged and inexpensive. Peripherally, it would be nice to have other features and functions such as location devices, mayday devices and gas detection. The wants expressed by first responders in the workshop were consistent with manufacturers' own expectations. For years, manufacturers have concentrated on reducing costs that they could sell cameras for less. But that may soon change.

NFPA involvement

The National Fire Protection Association is taking an increasingly active role in thermal imaging. Today, NFPA is developing standards to address thermal cameras in the same way it addressed SCBA, PASS devices, turnout gear, helmets and other PPE.

NFPA is nearing the finalization of the Electronic Safety Equipment standard, an umbrella standard that covers most types of electronic equipment used by the modern first responder. The standard will enable the certification of compliant equipment and enhance firefighter safety by outlining specific standards of quality and fit for use.

There is a trade-off to this, however. Because the standard seeks to cover all types of electronic equipment and is not specific to thermal imagers, there's wording in the standard that isn't necessarily practical with the design of today's thermal imagers. Intrinsic safety, for instance, is a proposed requirement. If that passes, camera prices could easily double.

To address this issue, first responders and manufacturers are working together to create a draft proposal for consideration as a new NFPA standard specific to thermal imaging. If adopted, the requirements set forth in the Thermal Imaging Camera standard will likely supersede the ESE standards but are not likely to have performance criteria less than those specified in the umbrella standard.

The TIC standard seeks to make cameras more uniform. For instance, regardless of the brand of camera, the on/off button always will be located in the same place. On-screen colorization with temperature thresholds will be uniform. The battery-level indicator will look the same in all cameras. Furthermore, NIST will be developing performance metrics for thermal-imaging cameras such that every firefighter can compare offerings more easily.

Though a finalized NFPA standard on thermal imagers is likely to be five years away, standardization will be advantageous to first responders in situations such as mutual aid where the use of another department's camera may be required. This also will allow basic imager training to be largely standardized.

Price trends

Over the past several years, first responders have enjoyed reductions in the selling prices of thermal cameras. Once a $25,000 item, departments can now acquire certain types of cameras for less than $10,000. There are two primary factors that enabled this reduction. First, camera companies began to use less expensive 160- by 120-pixel detectors versus the higher performing 320- by 240-pixel detectors used in the late 1990s. Second, overall volume for detectors has increased. Infrared detectors are much like computer chips — the higher the volume, the lower the cost. It's likely that detectors will continue to decrease in cost as more of them are required by applications such as automotive night vision, machine vision, thermography, surveillance, law enforcement and firefighting.

However, that doesn't mean that camera prices will continue to decline; in fact, it is unlikely. The cost to make cameras that comply with the ESE standard — costs not directly associated with the infrared detector — will rise significantly. Even as infrared technology gets cheaper, fire departments are not likely to continue to enjoy the full benefits of the reduced detector costs. In fact, they may even increase over time, the same way SCBA prices increased when the CBRN standard was released.

Complementing this trend, first responders have increasingly become technology savvy. Modern first responders understand electronics and their tradeoffs. Increasingly, technology-savvy departments have insisted on a move back to high-performance, high-resolution cameras. To satisfy that demand, manufacturers released new high-resolution thermal cameras. Two years ago, ISG released the original K1000 Elite camera, which used a high-resolution 320- by 240-pixel infrared detector.

Recently, Bullard released the T4, also using a high-performance 320- by 240-pixel detector. MSA is rumored to have one on the way, too. The shift to better quality will push prices upward, particularly for these high-performance models. Lower-resolution offerings such as the MSA Evolution 5200, Bullard T3 Max and ISG K80 will still be available but will be pretty much targeted to budget-challenged departments.

Integration woes

As mentioned earlier, the most important consideration to first responders is the price of cameras, bar none. The most efficient way to manufacture a thermal camera is as a stand-alone unit. Although integrating cameras into SCBA appears on the surface to be beneficial, it's limited by expensive in-mask display systems that result in higher prices. Furthermore, a thermal camera is used in many situations where SCBA isn't worn. As a result, manufacturers must find solutions that make in-mask systems dual-use.

One possible solution is the use of wireless technology, which make it possible to transmit images from a camera sensor to an in-mask display; however, designers have had difficulty isolating the imaging signals from other wireless systems such as radios used on the fireground. These and other devices tend to interfere with imaging transmitters.

As such, an SCBA-integrated thermal imager will complement the use of handheld devices but isn't likely to replace handheld units. Departments with budgets large enough to accommodate both types of camera systems will opt to complement their handhelds with SCBA-mounted systems. Budget-restricted departments will likely continue to opt for a utilitarian, multiuse handheld camera.

An SCBA-mounted camera will always cost more than a handheld unit. It is just simply more complicated to build. Expect, however, TIC manufacturers that also make SCBA to offer integrated units in the future.

Similar problems existed with helmet-mounted imagers. In the mid-1990s, Cairns offered a system called the CairnsIRIS. In the late-1990s, FLIR Systems offered the FireFLIR. Both were helmet-mounted, and both were deemed rather cumbersome to use at the time. First responders preferred to use handheld units, and both products subsequently were withdrawn. Helmet-mounted systems are largely constrained by cost in the same manner as SCBA-integrated units. Displays have to be heads-up to result in a truly mass-marketable configuration.

However, helmet-mounted units, particularly those that aren't permanently mounted to a helmet, appear more promising than SCBA-mounted units because theoretically they can be passed from one firefighter to another. Furthermore, a first responder wears his helmet in virtually every situation, whether in a fire or otherwise. Many manufacturers are conducting research to determine the feasibility of these systems, particularly in conjunction with technology research for future generation cameras. As technology becomes smaller and lighter, expect offerings to become available.

Future options

There's much to be said about technology, which is a major driver for the cost and performance of thermal cameras. There will be new cameras using new technology. Manufacturers aren't standing still. Expect new features and functions such as location systems, gas detection and radiometry. It's likely that as new technology becomes available, cameras will become better.

Manufacturers are considering a number of new approaches:

Microcantilevers

Instead of using vanadium oxide or barium strontium as the sensing material, a microcantilever will use dissimilar metals to sense changes in heat. These sensors, if they work as envisioned, will have added performance and lowered cost, thereby helping reduce the price of the imaging engines. There are a few companies working on this type of technology, but none have finalized versions.

Optically based systems

Another possibility is an approach being developed by Redshift Systems of Massachusetts. Redshift uses an optically tuned filter that, when placed in front of a normal complementary metal-oxide semiconductor or charge coupled device camera, produces thermal images. Like microcantilevers, the technology has the potential of being low in cost. While its thermal sensitivity is not likely to match current systems like for like, it eliminates the need to freeze-frame while switching from EI to normal modes and vice-versa. A camera that doesn't freeze-frame would be a huge advantage to first responders.

Thermopile microelectromechancial systems

MEMS systems are yet another approach. Thermopiles offer the potential of being relatively low cost while offering relatively high performance. Again, the employment of a MEMS-based detector will have added cost utility to manufacturers by helping offset the cost of a camera engine.

All the major camera manufacturers continue to examine and evaluate new approaches for next-generation thermal imagers, but the fire application is very demanding. Fire cameras must withstand very high levels of heat and must be able to withstand the physical demands of firefighting without breaking, so it may be quite some time before these new systems make their way into our industry.

The ultimate beneficiary to these technical advances will be the fire service with tougher and smaller cameras, standardized switches and display icons, and higher-performing cameras in the next 10 years. Fire cameras have become one of the largest applications of thermal-imaging technology today. Technology providers, who in the past had military applications in their crosshairs, are paying more attention to the needs of the fire service. Technology today is being developed with more consideration of the fire industry's unique operating environment. It is not inconceivable that one day we will have a sensor designed specifically for fire applications.

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David A. Little is the president and chief executive officer of ISG Thermal Systems. He has been involved in the fire service equipment industry for 15 years, with the 10 most recent years specific to thermal imaging.