Abstract: Disclosed is an alarm unit having an alarm controller, the alarm controller being operatively connected to a plurality of implements within the alarm unit having a mechanical actuator and a magnetic sensor and at least one of a visual source and an audible source, wherein the alarm unit: monitors for input to initiate one of a plurality of self-tests including: a first test, initiated by actuation of the mechanical actuator without actuation of the magnetic sensor, and a second test, initiated by actuation of the mechanical actuator with actuation of the magnetic sensor, and wherein the first test differs from the second test.

Abstract: Disclosed is an alarm unit having an alarm controller, the alarm controller being operatively connected to a plurality of implements within the alarm unit having a mechanical actuator and a magnetic sensor and at least one of a visual source and an audible source, wherein the alarm unit: monitors for input to initiate one of a plurality of self-tests including: a first test, initiated by actuation of the mechanical actuator without actuation of the magnetic sensor, and a second test, initiated by actuation of the mechanical actuator with actuation of the magnetic sensor, and wherein the first test differs from the second test.

Abstract: A method of manufacturing an electrochemical sensing system is provided. The method includes forming a sensor with a first sensing element disposed on a sensor, the first sensing element configured to detect a target gas, disposing a second sensing element on the sensor, the second sensing element configured to detect the target gas, and coupling a protective feature to the second sensing element, the protective feature configured to prevent non-target gases from contacting the second sensing element. The sensor is configured such that if the first sensing element generates a current exceeding a first threshold current value and the second sensing element does not exceed a second threshold current value it is determined that the first sensing element is contaminated and a restoration protocol is performed on the first sensing element.

Abstract: A method of manufacturing an electrochemical sensing system is provided. The method includes forming a sensor with a first sensing element disposed on a sensor, the first sensing element configured to detect a target gas, disposing a second sensing element on the sensor, the second sensing element configured to detect the target gas, and coupling a protective feature to the second sensing element, the protective feature configured to prevent non-target gases from contacting the second sensing element. The sensor is configured such that if the first sensing element generates a current exceeding a first threshold current value and the second sensing element does not exceed a second threshold current value it is determined that the first sensing element is contaminated and a restoration protocol is performed on the first sensing element.