The Heat is On

Finding the resources to secure our most precious resource -- using thermal imaging cameras to guard water treatment plants

• By Mike Studer
• May 01, 2005

The lack of attacks launched against water treatment plants is by no means an indication that they are invincible. While treatment plants aren't typically seen as high profile targets, they are at risk of infiltration and/or sabotage. Plants, many of which are based in or near residential areas, purify water for vast regions. Destroying or disabling a single facility could devastate an entire national region for an indefinite amount of time and create a real sense of uneasiness among those forced to suffer without water for a long time to come.

Water treatment plants are not blind to this threat to their infrastructure. In fact, some have turned to thermal imaging technology to improve their security. By integrating thermal imaging cameras into their (closed-circuit television) CCTV surveillance systems, water treatment plants are finding that stopping intruders has become easier than it was when they were using traditional security cameras. In addition, water treatment plants in residential areas have been able to avoid the use of bright security lighting that is bothersome to those who live in the neighborhood.

Let's take a look at a hypothetical example of a water treatment plant that provides service to a heavily populated area that recognized the need to step-up security measures with thermal imaging cameras.

Facing the fact that security must be provided 24 hours a day, the plant determined that it needed a security solution that would enable security personnel to watch the perimeter of the facility via monitors. With this ability, security personnel could detect problems and proactively stop any intruders before they were able to breach security. Perhaps just as important, the plant wanted a system that did not require the use of bright security lighting. The company believes that part of good corporate citizenship involves using light levels that don't hinder the aesthetic draw of the neighborhood.

To address its major security needs, the water treatment plant installed thermal imaging cameras at key points throughout the facility. By integrating thermal imaging cameras with the existing CCTV network, the security personnel were able to monitor the perimeters during both day and night.

To fully understand the potential of thermal imaging for sensitive structures such as water treatment plants, one must fully grasp the technology. Criminals are a varied bunch. Their intelligence levels cover a wide spectrum, but, regardless of their IQ, most criminals have enough sense not to try to break into a facility in broad daylight. The night offers more cover -- both for the infiltration and the escape. The thing is, most facility video surveillance equipment is designed to be effective primarily during the daytime. Darkness severely degrades the performance capabilities of those video surveillance systems.

Many organizations believe the best way to combat the darkness is with security lighting systems. While security lighting can be effective in limited scenarios, purchasing and installing an adequate amount of security lighting can be expensive. In addition, many facilities are located in areas where security lighting is obtrusive or impractical because they are located residential areas and near bodies of water.

While many different technologies have been tried as a solution for nighttime surveillance, the benefits of thermal imaging are attracting more and more security managers. To understand why thermal imaging is becoming so popular, it helps to review the attributes of several of today's popular forms of surveillance technology. The most common types are as follows:

• Thermal imaging
• Day TV with lights
• CCTV with infrared illumination
• Image intensification

Thermal Imaging
Thermal imaging detects the self-emitted heat of objects. As such, thermal imaging cameras need no visible light to produce an image. Typically, the image produced is black and white, where the hotter objects are whiter and the cooler objects are darker. Thermal imaging essentially makes people and running vehicles "glow" white against the darker, cooler background. When viewing a display screen, it is virtually impossible to miss the glowing intruders, and they cannot use camouflage to blend in with the background. It is possible to "trick" some other technologies using camouflage.

Unlike other security camera solutions, thermal imagers are extremely effective for long distances, identifying objects with a heat signature from a few feet away to a few thousand feet away and "seeing" objects through smoke. In addition, because they detect objects based on differences in temperature, they are effective during both day and night. This high level of effectiveness makes thermal imagers a proactive security system as opposed to reactive. They provide the ability to stop intruders long before the intruders actually breach the perimeter of a facility.

Thermal imaging has proven to be a successful solution for a host of security scenarios, including the following:

• Providing vision at night where lighting is undesired and 24x7 surveillance is needed
• Conducting surveillance over waterways, lakes, and ports where water and lighting options are impractical
• Enabling surveillance through weather conditions where other technologies will be challenged
• Providing low maintenance requirements for those based in remote or difficult locations
• Offering low-cost operation over the life of the product

Thermal imaging has emerged as a common addition to the integrated security package. Companies are relying on thermal imaging for specific applications where no other technology can perform.

Many security and surveillance professionals have indicated that a nighttime breach of security is likely and that the security solutions currently available are inadequate because it is easy to miss activities in dark areas. With thermal imaging, security professionals can detect intruders at long ranges with unprecedented clarity. They now can quickly identify a security breach and proactively respond to mitigate it instead of reacting to minimize the exposure or responding when the situation is optimal for the perpetrators.

Day TV with Lighting
Day TV (DTV) with lighting provides a splash of light that makes it possible to use traditional cameras to watch for intrusion. The cost of individual cameras is not high, but a large number of cameras and multiple lights must be installed to cover a facility adequately. This drives up the cost of this solution. In addition, it calls attention to a facility, especially if the location is remote or on a coastline where lights become a beacon. Also, if some areas are lit while others are not, intruders know exactly where to go to breach security -- the dark areas.

Often, electric lighting is considered imperative for parking lots and other frequently visited controlled areas. But lights are indiscriminate, offering the same level of illumination to intruders as they offer to security professionals. In addition, intruders know exactly where the security is, and, conversely, they know where it isn't. This makes lighting and DTV ineffective for many types of facility security.

CCTV with Infrared Illumination
Once DTV with lighting has been ruled as ineffective for the security needs of a particular facility, security professionals often move on to more technical solutions. Infrared illumination cameras, used in CCTV systems all over the world, are the first of the more sophisticated systems. Infrared illumination cameras have some capability in the 0.4 ìm (micrometer) to 1.1 ìm wavelength band, but usually they need to enhance the illumination in a scene to be able to detect images. In other words, they need some illumination to work in semi-darkness, and they get this illumination with Infrared (IR) sensors. Several different types of technology fall into the Infrared illumination category. These categories include diode, IR lamp, and laser.

Diode technology is small, inexpensive, uses a low level of power and is widely available. Its drawbacks are that it illuminates only very short distances and is degraded significantly by certain types of weather. IR Lamp technology offers increased illumination distance, but it is expensive, physically large, uses high levels of power, and is degraded by weather. Laser technology offers the greatest illumination distance of the three types and sees through most types of weather, but those capabilities make laser solutions expensive. In addition to being cost prohibitive, laser technology is very large, uses extensive amounts of power, has a narrow field of illumination, is unsafe to the eye, and is available primarily for military applications.

Regardless of the type of illumination, each of these cameras measures the contrast in reflected light and reflected near IR. Reflected energy depends on the color and sheen of objects in the field of view. An individual attempting to be stealth-like and avoid the camera's watchful eye could wear dark colors and shun the use of shiny objects, etc., to limit the effectiveness of the cameras.

As discussed, for all types of illumination, range is a key factor in the performance of a CCTV with IR. These cameras function best at close range -- within about 75 feet. At that range, the Infrared illumination can take effect. For CCTV with Infrared illumination or Day TV systems, lighting an entire coastline with lights or illuminators to see even 1,000 feet is not cost effective. Even if it were technically possible, it would be prohibitively expensive and a logistical difficulty to install and maintain.

Image Intensification
Image intensification, another sophisticated type of illumination, works by amplifying the ambient light of a scene; therefore, it must have an illumination source to be effective. Image intensification is one of the most widely known of the so-called "night vision" systems. The grainy green images, as seen on news shows and war coverage, use the ambient light of stars, the moon, or other lighting sources to work.

A common problem with image intensifiers is the "blooming effect" that happens when a light enters the scene suddenly. A small point source of light will bloom and obscure other objects in the scene. This means that if light levels change rapidly, the image intensifier needs time to adjust to the new levels. Intensifier makers try to throttle down the throughput of the devices when light levels increase, but it takes reaction time ? just as the human eye does when it is dilated. It is simple to blind such cameras with car headlights, powerful flashlights or other sources of bright light. From a security standpoint, this susceptibility to the blooming effect makes these cameras effective only on a marginal basis. Intruders who have some knowledge of the systems could use bright lights to cause a blooming effect that would hide what they're doing. They also could create a blooming effect that would attract attention and act as a distraction, enabling additional intruders to infiltrate the facility from a separate location.

The Future of Thermal Imaging in Security
As discussed, there are several technologies available that improve on the capabilities of the naked eye. However, many of those technologies have significant drawbacks or can be easily thwarted. As a result, thermal imaging's popularity among security managers continues to increase. As the volume of installed systems grows, price points are likely to decrease. This bodes well for facilities of all types, but it is particularly good news for facilities located in areas where other types of security camera systems have been impractical or ineffective.

Technological advances in thermal imaging technology also are likely to increase its use as part of an overall security solution. As the adoption of thermal imaging technology increases, it will continue to be integrated to work with a host of security applications, including motion detectors, access control systems and specialized software. Also, its ability to see over greater distances will increase in the years to come, making the technology even more effective for security purposes.

Ultimately, this increased level of security is beneficial to just about everyone, except, of course, for criminals. As intruders and saboteurs grow more sophisticated, water treatment plants and other sensitive facilities must use more sophisticated measures to deter attacks. Thermal imaging cameras offer a level of security that helps protect these facilities and the precious assets held within.

This article originally appeared in the 05/01/2005 issue of Environmental Protection.