Infrared Technology

Infrared technology, also known as thermography, measures differences in heat. This technology allows us to see "inside" your walls, identifying possible issues that are not apparent through conventional inspection methods.

Infrared Inspections

Infrared thermography, thermal imaging, and thermal video are examples of infrared imaging science. Thermal imaging cameras detect radiation in the infrared range of the electromagnetic spectrum and produce images of that radiation, called thermograms. Since infrared radiation is emitted by all objects above absolute zero according to the black body radiation law, thermography makes it possible to see one's environment with or without visible illumination. The amount of radiation emitted by an object increases with temperature; therefore, thermography allows one to see variations in temperature.

Infrared cameras can be used during building inspections and energy audits to locate problems that can be found by viewing differences in temperature, which the camera sees as infrared radiation and presents as gradient colors. Every object warmer than absolute zero emits infrared radiation, which is invisible to the naked eye but is read by thermal imaging. Being able to view this allows inspectors to locate problems that would otherwise be more difficult and time-consuming to find. Understanding data that the camera displays is essential in utilizing IR technology correctly and to its fullest capabilities.

In a home inspection, variations in temperature can indicate a number of issues including vermin, poor insulation, substandard window installations, roof leaks, plumbing issues and more. Thermal signatures can also indicate heat leaks in faulty thermal insulation and can use the results to improve the efficiency of heating and air-conditioning units.

Advantages of thermography

• It shows a visual picture so temperatures over a large area can be compared
• It is capable of catching moving targets in real time
• It is able to find deteriorating, i.e., higher temperature components prior to their failure
• It can be used to measure or observe in areas inaccessible or hazardous for other methods
• It is a non-destructive test method
• It can be used to find defects in shafts, pipes, and other metal or plastic parts[4]
• It can be used to detect objects in dark areas

Thermal Images in Inspection Reports

Thermal images are generally used in inspection reports to visually document problems found on site. The image captured with the IR camera can be presented alongside a digital, visible-light photo, along with a description of the issue that was discovered. Some infrared cameras incorporate the ability to switch between standard, digital and IR-imaging modes for just this purpose. The inclusion of standard, digital images makes side-by-side comparisons easier for both inspectors and clients to understand because it shows any obvious, visible defects. But IR doesn't stop at the obvious. The IR image shows accurate evidence of a defect that can't be fully captured with the digital camera. For example, a digital image may show a dried water stain at a wall-ceiling junction, while its IR counterpart displays a dark spot in the same area. The clear advantage of thermography is that while the digital image displays what looks like an old stain, the IR image confirms that moisture is still present, requiring further investigation to locate and remediate the problem.

Infrared Imaging for Electrical Inspections

Thermal or infrared (IR) imaging in the practice of building inspection has been used to inspect electrical systems for some time now and its use has steadily grown increasingly popular. Since components in electrical systems almost always overheat before they fail, problem areas are more easily and safely found when viewed through an IR camera. Infrared imaging allows apparent temperatures to be seen as gradient colors, with hotter spots displayed as brighter colors, and cooler (and wetter) spots displayed as darker colors. When a malfunctioning electrical component or connection is generating more heat than it should be, its apparent temperature will make it stand out right away when viewed through thermal imaging.

What kinds of problems can be detected?

During an inspection, electrical equipment, such as distribution panelboards, switch boards, contacts, transformers, receptacles, and service and control panels, can be examined through an IR camera. By viewing apparent temperature differences, inspectors can identify and document problems, such as loose connections and overloaded circuits, which are the most common causes of electrical fires. Other issues, such as transformer cooling problems, induced currents, arcing, and motor-winding faults, also become readily apparent.

Thermal imaging can detect electrical issues that include:

• excessively hot or loose connections;
• overloaded wiring;
• overloaded circuits;
• overloaded transformers;
• overloaded motors;
• arcing; and
• excessive harmonics.

Advantages of Using an IR Camera for Electrical Inspections

Because viewing apparent temperature differences through an IR camera requires no physical contact and can cover a lot of space in one sweep, no other technology allows electrical faults to be found as safely and as quickly as thermal imaging. Another important benefit is that it allows problem areas and components to be located before damage from any serious failure or electrical fire occurs. This helps ensure safety. It can also save money that might otherwise need to spent on extensive repairs.

Here’s a list of advantages of using an IR camera for electrical inspections:

• It’s non-contact, which helps ensure a safe inspection.
• It’s fast and accurate.
• It helps identify problems before they cause serious failure or an electrical fire.
• It’s non-intrusive, so there is no interruption of power during the inspection.
• It can be used as part of inspections that are conducted as preventative maintenance.
• IR equipment is light and portable.
• It provides documentation of problems.

As thermography has advanced, thermal imaging has become popular in the field of inspection because IR cameras are fast becoming an indispensable tool in helping inspectors locate and documents defects quickly and accurately.

Consumers should always seek inspectors who are Infrared Certified by looking for the Infrared Certified logo.

Sources: Wikipedia, InterNACHI articles