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 of at least 35 percent. Lawn mowers produce GHG emissions. A minimum-maintained lawn management practice with clipping recycling, and minimum irrigation and mowing, is recommended to mitigate global warming effects from urban turfgrass system Mowers can create significant noise pollution, and could cause hearing loss if used without hearing protection for prolonged periods of time. Lawn mowers also present an occupational hearing hazard to the nearly 1 million people who work in lawn service and ground-keeping. A recent study assessed the occupational noise exposure among groundskeepers at several North Carolina public universities and found noise levels from push lawn mowers