Exhaust gas gas is undesirable, noxious, or toxic substances, such as carbon monoxide (CO) from incomplete combustion, hydrocarbons (properly indicated as CH, but typically shown simply as "HC" on emissions-test slips) from unburnt fuel, nitrogen oxides (NO) from excessive combustion temperatures, and particulate matter (mostly soot). Exhaust gas temperature (EGT) is important to the functioning of the catalytic converter of an internal combustion engine. It may be measured by an exhaust gas temperature gauge. EGT is also a measure of engine health in gas-turbine engines (see below). During the first two minutes after starting the engine of a car that has not
Exhaust hood cancellation, temperature display, user presets (memory), and so on. Extractor hoods may be made from a variety of materials, including: stainless steel, copper, bronze, nickel silver, zinc, tempered glass, wood, aluminum, brass, heat-resistant plastics, and more. NFPA 96 Standard for Ventilation Control and Fire Protection of Commercial Cooking says that mesh filters shall not be used. It requires that "Listed" grease filters shall be tested in accordance with UL 1046, Standard for Grease Filters for Exhaust Ducts. Greater hood over hangs are suggested to help contain cooking fires in the hood area protected by the fire suppression system. Exhaust hood