Abstract: An adverse condition detector that records historical data concerning the operation of the detector such that the detector can be interrogated by a technician. The microprocessor of the adverse condition detector monitors for alarm conditions and other important information related to the operation of the detector. Upon identifying an important characteristic of the detector operation, the microprocessor time stamps the information and stores the information within memory of the microprocessor. The detector includes an interface pad that is accessible from the exterior of the detector such that a technician can access the interface pad without removing the detector housing.

Abstract: An interface circuit and method for use in interconnected hazardous condition detectors is provided. This circuit and method prioritizes the various hazardous condition alarms to ensure that only the highest priority or greatest threat alarm is sounded when such a condition is detected. In this way a lower priority alarm that may be sounding will be switched to a higher priority alarm so that all interconnected detectors that have the capability will sound the higher priority alarm. This will reduce occupant confusion during a hazardous condition. The circuit and method also provides the ability to silence all interconnected detectors except for those sensing the hazardous condition to allow the occupant to locate the triggering alarm, and there for the location of the sensed hazardous condition.