Which of the following is a feature of thermography?

• A. Destructive technique
• B. Requires physical contact
• C. Depends on ambient light
• D. Non-Contact

Answer: (D)

Thermography works by detecting infrared radiation that objects emit and turning that heat energy into a temperature map. The defining feature is that it is non-contact—you can assess temperature patterns from a distance without touching the object, which is especially valuable for safely inspecting hot surfaces, electrical components, or moving machinery. It also doesn’t depend on ambient light, since it senses heat energy rather than visible light, so measurements are possible in dark or bright conditions. This makes thermography safe and fast, and unlike some other methods, it is not destructive and does not require physical contact.