Reducing air pollution from cars

Motor vehicles are Washington's largest source of air pollution. We're working to help reduce air pollution by managing clean car standards and by helping people learn how they help. You can reduce pollution from motor vehicles if you:


Vehicle pollutants harm our health and contain greenhouse gases that cause climate change. Burning gasoline and diesel fuel creates harmful byproducts like nitrogen dioxide, carbon monoxide, hydrocarbons, benzene, and formaldehyde. In addition, vehicles emit carbon dioxide, the most common greenhouse gas.

The good news is that you can reduce pollution from motor vehicles. Driving the cleanest vehicle you can afford and making everyday choices to drive less and drive smarter can make a big difference.

Drive less

Reducing the amount of miles you drive is the best way to reduce air pollution from motor vehicles. If you can, try walking or biking to your destination. You will emit zero pollutants. For longer distances, try riding the bus or train. If public transportation is not an option where you live, you may be able to carpool with someone who lives nearby. You will pollute less and spend less money at the pump.

Avoid idling

An idling vehicle gets zero miles to the gallon. Contrary to popular myths, cars do not need to "warm up" to run well in cold weather, and restarting your vehicle will not use more fuel than letting it run. Further, restarting your vehicle is unlikely to wear out the starter and other parts.

Drive a cleaner vehicle

Drive the most fuel efficient vehicle that meets your needs. Burning less fuel means emitting less of the harmful by products of combustion. There are many hybrid models and even all-electric vehicles on the market. Due to Washington's adoption of the more protective Clean Car standards, even traditional gasoline vehicles available in Washington run cleaner.

Electric, hybrid, and even compact fuel-efficient gas vehicles may not meet all drivers' needs. While the initial cost of some these vehicles may have put them out of reach for many of us, as they become more common, prices are becoming much more affordable. If your job or lifestyle requires a larger vehicle, you can compare the fuel economy of available vehicles. Driving the most efficient vehicle you can get reduces pollution and saves you money.

Maintain your vehicle

Regardless of what you drive, you can make sure your car runs as clean and efficiently as possible. Maintain your vehicle and keep it in good repair. Follow your owner's manual and make sure you schedule regular oil changes and other maintenance.

Newer vehicles have very complex emission controls to keep them running as clean as possible. If any of these controls are not functioning as designed, your vehicle will pollute more than it should. A check engine light on your dashboard means your vehicle is not operating as designed and needs repairs or maintenance. You should take your vehicle to a qualified automotive technician.

Keeping your tires properly inflated makes your vehicle run more efficiently and burn less fuel. You will find the correct tire pressure for your vehicle in your owner's manual.

Drive smarter

The way you drive can also influence how much pollution comes from your vehicle. Observing posted speed limits is one way to reduce pollution, and it's safer. Driving faster burns more fuel and emits more air pollutants. Accelerating gradually also burns less fuel. Getting a vehicle moving from a complete stop uses the most energy, so go easy on the accelerator. Try to anticipate the road ahead and avoid racing from red light to red light. Instead, strive to maintain a steady speed with less stop and go driving.