Forklifts operate primarily indoors, where the Occupational Safety and Health Administration (OSHA) regulates worker exposure to pollution. Emissions are an important consideration when making the choice between gasoline, diesel, propane, CNG, and electric forklifts. Properly maintained, propane forklifts operate with emissions well below standards set by OSHA and offer numerous environmental benefits: Clean Burning: Propane is an approved, clean fuel listed in the 1990 Clean Air Act and the Energy Policy Act of 1992 and is one of the cleanest burning of all fossil fuels. Low Emissions: Propane forklifts produce very low levels of emission contaminants, such as particulate matter, oxides of nitrogen, carbon monoxide and hydrocarbons. No Evaporative Emissions: Propane forklifts carry their fuel in sealed, pressure-tight containers. Unlike fueling with gasoline or diesel, there is no threat of evaporation or toxic spillage from the propane cylinders. Comparison of Forklift Environmental Impacts Type of Forklift Contaminants Emissions and Acoustics Propane • Less carbon build-up than gasoline powered forklifts • Few deposits in lubricating oil and engine parts • Very low heavy hydrocarbon or particulate emissions • Very low oxides of nitrogen emissions • Less carbon monoxide emissions than gasoline forklifts • Zero evaporative emissions because of sealed fuel system • Acoustics: Generally operate quietly; well below regulated noise limits Diesel/ Gasoline • Higher maintenance -contaminates lubricating oil and engine parts • Spillage will contaminate ground • Contains carcinogens in fuel and exhaust Electric • Battery disposal hazard • Discharging batteries emit harmful and combustible gases Propane forklifts have clean-burning engines — emissions can be reduced even further (or nearly eliminated) with the use of the following technologies: Carbon Monoxide Controllers Carbon monoxide (CO) controllers can be used to help keep forklift CO emissions below acceptable levels. They operate in the following manner: The controllers balance the carburetor air/fuel mixture as an engine slips out of tune with use. The controllers utilize a signal from an oxygen sensor in the exhaust stream to detect high CO levels and then adjust the amount of fuel entering the carburetor. The controllers typically adjust the fuel as often as ten times per second through the use of a solenoid valve. When the desired air/fuel ratio cannot be maintained, a dashboard warning light indicates the need for servicing. Additional benefits of a CO controller include increased fuel economy, extended engine life, reduced engine maintenance cost, and maximized engine performance. Three-way Catalyst Mufflers All fossil fuel-powered forklifts emit carbon monoxide, hydrocarbons, and oxides of nitrogen, which must be kept to safe levels when the equipment is operated indoors. The state-of-the-art technology for achieving emission reductions is the three-way catalyst system. Three-way catalyst mufflers can remove significant amounts of all three major pollutants (CO, HC, NOx) from forklift exhaust. CO and NOx can be reduced by as much as 99 percent (assuming good engine maintenance). PROPANE EDUCATION & RESEARCH COUNCIL