Which device is not used to detect fire accelerants?

The device not used to detect fire accelerants is chemical dyes. Chemical dyes, while they have various applications in industry and forensics, are not specifically designed to identify fire accelerants. Fire accelerants, such as gasoline or kerosene, require specific detection methods that can analyze their chemical composition or the gases they emit when burned.

In contrast, catalytic combustion detectors are specifically designed to identify flammable vapors and are often used in fire investigations to detect the presence of hydrocarbons. Gas chromatographs are instrumental in analyzing the specific chemical compounds present in a sample, making them highly effective for identifying accelerants. The benzydine test, while more commonly recognized for detecting blood, is also utilized in specific contexts related to chemical analysis where fire accelerants may be involved. Each of these devices and tests serves a unique purpose in the realm of fire investigation, particularly concerning the detection of accelerants.