The GammaRAE II Responder has the rapid response of a detector and the accurate dose measurement of a dosimeter in one compact design made specifically for first responders. This instrument provides a fast, two-second response to radiological threats, while providing high dose rate range coverage and accurate dose measurements. It alerts the wearer with a loud audible alarm; big, bright, flashing LEDs; and a built-in vibration alarm. For stealth operations, law enforcement personnel can disable each alarm individually.