The Offenders

Our Top Air Pollution Causes


Reducing the amount of particulate matter that gets into our air is not just a problem for the government or for science alone. It is a problem of the residents and visitors living and breathing in Maricopa County as well. Human activity is behind most of our top air pollution causes, but there is a way to clean our air. There are plenty of easy changes each of us can commit to do to stop polluting. Our website offers many tips you can incorporate into your daily routine to help make more clean air.  In addition, it’s important to know the rules; stay up to date with current air quality restrictions through our widget and website.

Cars, Trucks & ATVs

Exhaust from cars is a significant contributor to the particulate pollution problem. Being the single occupant in a vehicle on a regular basis adds pollution to the air. Further, driving off-highway vehicles (OHV) on dirt and unpaved roads stir up particulate matter that pollutes our air unnecessarily. OHV activity is restricted on most high pollution advisory days.

OHV Video:

Leaf Blowers and Lawn & Garden Equipment

Leaf blowers and gas powered lawn and garden equipment raise large amounts of dust, making them one of the primary air pollution causes of course particulate matter. The best alternative to a dust producing leaf blower is a rake or broom. The use of electric lawn and garden equipment is strongly recommended. Leaf blower use is restricted on government property during a high pollution advisory.

Weed Abatement Video:


Burning wood in fireplaces and wood stoves, as well as burning leaves, trash or other materials, contribute significantly to particulate matter, specifically PM-2.5. During the December holidays in 2011, the greater Phoenix area experienced levels of PM-2.5 three times higher than normal primarily due to wood-burning fires. Woodburning in residential fireplaces, chimineas, outdoor fire pits and similar outdoor fires are restricted during a high pollution advisory or health watch. This restriction includes woodburning fires at hotels and restaurants .

Regulated Industry

Many of the man-made sources of particulate matter are dust from construction activities, vacant lots, dirt roads, off-road areas where people have destabilized soil. Dirt that is tracked-out onto roads by vehicles causes problems because dust then gets constantly kicked by vehicles driving over it. Compliance and Enforcement Division focuses on these areas, as well as open-burning and fireplaces.

Commercial Ballooning Video:

Unpaved Parking Video: