Natural gas or propane gas leaks are very dangerous because they may not be detected immediately. If you smell gas, call your gas company, open windows, extinguish all flames and cigarettes, and do not light matches or smoke. Exit the building as quickly as possible. Gas fumes are extremely flammable and toxic. In the event you cannot get in contact with the gas company, call your local police or fire department immediately. Natural gas and propane gas are odorless gasses, however, odor additives are added to the gas for your protection. You would not be able to detect a gas leak if it did not have an odor and therefore it could produce potentially dangerous situations. It is crucial to have a gas leak repaired as soon as possible. When the gas company arrives, let them know the general area where you noticed the gas smell. Often leaks are caused by broken seals in gas pipe joints, malfunctioning ignitors (ig-NITE-ors), burners, faulty valves on appliances, or extinguished pilot lights. Your gas company can usually fix your gas appliances and check to make sure they are safe and free of leaks. For more information on gas leaks, contact your local gas company, plumbing supply company, or plumber.