Abstract: Methods and apparatus for monitoring gas sensor sensitivity. The method includes repeatedly determining the response of a gas sensor by exposing the gas sensor to a gas and measuring the gas sensor response; and transmitting the response, information identifying the gas detector, and the time of the calibration to a remote computer. The remote computer then calculates a trend of sensitivity for the gas detector over time based on the received responses and corresponding time values and determines a renewal time when the calculated trend intersects a predetermined value.

Abstract: Apparatus and Methods for Aggregated Leak Detection. The method includes determining the location of multiple portable personal gas detectors as each gas detector is moved and monitoring the gas level associated with each determined location. This information is then collated by associating the transmitted location and associated gas levels. Zones of concern associated with elevated gas levels detected by multiple gas detectors are then identified.