CFL bulbs is dangerous, because vapors well above safe levels continue to leak from the bags. The EPA and the Maine DEP recommend a sealed glass jar as the best repository for a broken bulb. Since the end of 2018, the export, import and manufacture of CFLs within the European Union has been prohibited under the EU Mercury Regulation. Recycling Health and environmental concerns about mercury have prompted many jurisdictions to require spent lamps to be properly disposed of or recycled, rather than being included in the general waste stream sent to landfills. Safe disposal requires storing the bulbs unbroken until they can be processed. In the United States, most states have adopted and currently implement the federal Universal Waste Rule (UWR). Several states, including Vermont, New Hampshire, California, Minnesota, New York, Maine, Connecticut and Rhode Island, have regulations that are more stringent than the federal UWR. Home-supply chain stores make free CFL recycling widely available. In the European Union, CFLs are one of many products subject to the WEEE recycling scheme. The retail price includes an amount to pay for recycling, and manufacturers and importers have an obligation to collect and recycle CFLs. According to the Northwest Compact Fluorescent Lamp Recycling Project, because household users in the U.S. Northwest have the option of disposing of these products in the same way they dispose of other solid waste, in Oregon "a large majority of household CFLs are going to municipal solid waste". They also note the EPA's estimates for the percentage of fluorescent lamps' total mercury released when they are disposed of in the following ways: municipal waste landfill 3.2%, recycling 3%, municipal waste incineration 17.55% and hazardous waste disposal 0.2%. The first step of processing CFLs involves crushing the bulbs in a machine that uses negative pressure ventilation and a mercury-absorbing filter or cold trap to contain mercury vapor. Many municipalities are purchasing such machines. The crushed glass and metal is stored in drums, ready for shipping to recycling factories. Greenhouse gases In some places, such as Quebec and British Columbia in 2007, central heating for homes was provided mostly by the burning of natural gas, whereas electricity was primarily provided by hydroelectric power. An analysis of the impacts of a ban on incandescent light bulbs at that time introduced the notion that in such areas, heat generated by conventional electric light bulbs may have been significantly reducing the