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
Lawn mower demonstrate proper judgment and maturity. Persons using a mower should wear heavy footwear, eye protection, and hearing protection in the case of engine-powered mowers. A 2001 study showed that some mowers produce the same amount of pollution (emissions other than carbon dioxide) in one hour as driving a 1992 model vehicle for . Another estimate puts the amount of pollution from a lawn mower at four times the amount from a car, per hour, although this report is no longer available. Beginning in 2011, the United States Environmental Protection Agency set standards for lawn equipment emissions and expects a reduction