Work is performed indoors and outdoors in varying weather conditions and may involve exposure to mechanical equipment, plumbing systems, confined spaces, sewage, chemicals, pressurized piping, natural gas systems, noise, dust, moisture, and other conditions commonly associated with commercial plumbing maintenance. In addition to the above requirements, the following are sought: Thorough knowledge of commercial plumbing systems, domestic water distribution, sanitary sewer, storm drainage, natural gas piping, pumps, water heaters, and plumbing fixtures.