Gas detector in industrial refrigeration processes and biological degradation processes, including exhaled breath. Depending on the required sensitivity, different types of sensors are used (e.g., flame ionization detector, semiconductor, electrochemical, photonic membranes). Detectors usually operate near the lower exposure limit of 25ppm; however, ammonia detection for industrial safety requires continuous monitoring above the fatal exposure limit of 0.1%. There are several different sensors that can be installed to detect hazardous gases in a residence. Carbon monoxide is a very dangerous, but odorless, colorless gas, making it difficult for humans to detect. Carbon monoxide detectors can be purchased for around US$20–60. Many local
Inductive discharge ignition this kind of system was invented by Charles F. Kettering in about 1909 and was known by some as the Delco ignition system. Later patent applications to the US Patent Office make reference to the "Kettering ignition system". This type of ignition system was used on automobiles, trucks, lawn mowers, tractors, chainsaws, and other gasoline-powered machinery with great success for many decades until the development of capacitive-discharge ignition systems. Inductive discharge ignition Inductive discharge ignition systems were developed in the 19th century as a means to ignite the air-fuel mixture in the combustion chamber of internal combustion engines. The first