Explosives trace detectors (ETD) are security equipment able to detect explosives of small magnitude. The detection can be done by sniffing vapors as in an explosive vapor detector or by sampling traces of particulates or by utilizing both methods depending on the scenario. Most explosive detectors in the market today can detect both vapors and particles of explosives. Devices similar to ETDs are also used to detect narcotics. The equipment is used mainly in airports and other vulnerable areas considered susceptible to acts of unlawful interference. == Characteristics == === Sensitivity...