Abstract: Systems and methods thereof for detecting at least one material in an environment prior to the environment reaching levels deemed dangerous by conventional monitors and standards includes at least one sensor adapted to measure a level of the at least one material in the environment surrounding the sensor, at least one notification device adapted to produce a signal, and a memory comprising a preprogrammed level of the at least one material in the environment. The system is programmed with a minimum notification level of the at least one material in the environment that is below the preprogrammed level and is adapted to notify a user with the signal if the level exceeds the minimum notification level. The frequency and/or amplitude of the signal is changed as the level approaches the preprogrammed level.

Abstract: A method and instrument capable of accurately detecting the presence of a gas and accurately measuring the concentration of the gas in, for example, the environment. The method and instrument sense the presence of a gas with a sensing element whose output is linear to the concentration of the gas in the environment, and process the output of the sensing element through a nonlinear amplifier having a higher gain at lower levels of the output than at higher levels of the output so that the nonlinear amplifier amplifies the output of the sensing element at the lower levels thereof and avoids signal saturation at the higher levels thereof. The method and instrument then deliver the amplified output of the nonlinear amplifier to an audio circuit that produces an audio output having a property in proportion to the amplified output of the nonlinear amplifier.

Abstract: A method and instrument capable of accurately detecting the presence of a gas and accurately measuring the concentration of the gas in, for example, the environment. The method and instrument sense the presence of a gas with a sensing element whose output is linear to the concentration of the gas in the environment, and process the output of the sensing element through a nonlinear amplifier having a higher gain at lower levels of the output than at higher levels of the output so that the nonlinear amplifier amplifies the output of the sensing element at the lower levels thereof and avoids signal saturation at the higher levels thereof. The method and instrument then deliver the amplified output of the nonlinear amplifier to an audio circuit that produces an audio output having a property in proportion to the amplified output of the nonlinear amplifier.