Exhaust gas that they produce smaller quantities of toxic pollutants (e.g. oxides of nitrogen) than petrol and diesel engines of the same power. They produce larger quantities of carbon dioxide but less carbon monoxide due to more efficient combustion. Researchers from the University of California, Los Angeles School of Public Health say preliminary results of their statistical study of children listed in the California Cancer Registry born between 1998 and 2007 found that traffic pollution may be associated with a 5% to 15% increase in the likelihood of some cancers. A World Health Organization study found that diesel fumes cause an increase
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