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
Sensation Lawn Mowers of snow blowers were developed under the name of Snow Blow. Phelps held patents on over 20 innovations in the lawn industry including the first for a rotary mower grass catcher U.S. patent number 2,855,744 in 1960. In 1966 Phelps sold the company to local real estate agent Frank Rogers who in turn sold it to a group of Chicago investors headed by Carl Johnson the plant was moved to 16th and Evans Streets in North Omaha, Nebraska. The "Sensation Mike Bike" was named after Frank Rogers son Mike. In November 1982 the Sensa after Frank Rogertion Lawn Mower Company