All objects with a temperature above absolute zero emit levels of thermal radiation. This radiation, although invisible to the human eye, can be detected by thermal camera sensors, which display images of invisible infrared or ‘heat’ radiation. A superb tool for providing situational awareness in the daytime, total darkness or within adverse weather conditions, capitalising on this attribute, thermal cameras can be used within a wide variety of applications.

Perimeter protection with dual-lens thermal cameras
Particularly suited to operating in changing light conditions, total darkness, or other challenging weather conditions such as rain, fog or snow, thermal cameras can provide the perfect platform on which to build more effective, 24/7 perimeter surveillance systems.

Whereas the latest thermal camera models have excellent detection/location performance, image identification is taken to the next level when thermal imaging is supported by a high definition video surveillance camera, where identification detail can also be displayed and monitored. In this respect, the choice of a ‘bi-spectrum’ integrated thermal, and bullet or PTZ speed dome video camera will yield the optimum solution for the majority of perimeter surveillance applications. Integrated with intelligent video applications, such as line crossing or intrusion detection, bi-spectrum cameras can automatically trigger an alert and at the same time, trigger a traditional PTZ camera to supply essential video detail to an operator.

Stefan Li says: “The combination of a thermal and video camera in one housing is especially effective in theft prevention and border enforcement applications, not only to detecting a target at distance, but also to reveal features of an intruder or object at shorter distances.”

Handheld thermal cameras
Thermal technology can be used in many other applications. Mobile thermal imaging devices can open up a new world of portable thermal imaging uses for some applications. Examples of which are for security patrols at night, where a handheld thermal camera is very helpful to locate objects in the dark. Here thermal imaging can provide an effective tool to track targets, ensure personal safety, and detect unauthorised persons, even through camouflage.

Stefan Li says: “Law enforcement agencies, emergency organisations and utility companies can use handheld thermal equipment to great effective in pursuit of their work. The most vital of these being by fire fighters, who commonly use thermal imaging to see through smoke, locate people and localise fire hotspots”.

Law Enforcement agencies use thermal technology to enhance surveillance activities, locate and apprehend suspects (officers are very impressed by the ability to locate suspects in dark alleyways due to their radiated heat, even when they are hiding behind an object), investigate crime scenes, and conduct search and rescue operations.

For utilities use, power line maintenance technicians can easily locate overheating joints and conductive parts, to eliminate potential problems before they have a chance to develop into a catastrophic failure and break in power transmission.

Predictive maintenance
The deployment of thermal imaging by the manufacturing industry is the most mature commercial application. Here, the ability to accurately measure temperature data using thermal imaging provides maintenance personal with vital information about the condition of all kinds of mechanical machinery, electrical power panels and other equipment components.

Used across a wide range of industries including manufacturing, power plants and petrochemical plants, thermal imaging can help to make production facilities more efficient, optimise the production process, reduce costly production downtime and support health & safety by avoiding the potential for injuries to staff.

Examples where thermal imaging is used for predictive maintenance of mechanical equipment inspection and monitoring of hot or cold spots include insulated vessels and pipelines, heat exchangers, air coolers, furnaces and reactor vessels, boilers, fluid or gas flow relief valves, steam traps, bearings and gears. It can also be used for predictive maintenance of electrical equipment inspection and monitoring including electrical connections, fuse panels, cables, transformers, motors and windings, electrolytic cells, and high voltage switchgear.

“Employing resolutions up to 640x512, Hikvision’s thermal image quality is greatly enhanced being supported by Adaptive AGC, 3D DNR, DDE, and high sensitivity for accurate thermography, dynamic fire detection and temperature anomalies. Add to this mix the integration of Video Content Analysis (VCA), and Hikvision thermal cameras can really help to dramatically reduce the rate of false alarms by confirming triggered events and improve detection rates”, says Stefan Li.