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Air Quality in the Portland Region

Portland's air currently meets all federal air quality health standards. These standards exist for six pollutants known as the criteria pollutants (carbon monoxide, ozone, particulate matter (PM2.5 and PM10), nitrogen oxides, sulfur oxides and lead. The criteria pollutants of most concern in Portland are ozone and fine particulate matter.
In recent years air toxics have taken center stage as pollutants of concern throughout the Portland region. Air toxics are generally defined as air pollutants known or suspected to cause cancer or other serious health problems. Air toxics include diesel soot, benzene, polycyclic aromatic hydrocarbons (tar-like by-products from auto exhaust and other sources), and metals including manganese, nickel, and lead. Air toxics come from a variety of sources including cars and trucks, all types of burning (including fireplaces and woodstoves), businesses, and consumer products such as paints. There are no federal standards for air toxics.

​​DEQ is developing a comprehensive plan to meet the health-based benchmarks for all air toxics in the Portland area. DEQ formed the Portland Air Toxics Solutions Advisory Committee to help develop the plan. The plan may also include strategies to reduce unacceptable risks in localized areas like Northwest Portland.

DEQ operates three programs that achieve significant reductions of air toxics from vehicles: the Employee Commute Options Program, the Vehicle Inspection Program and the Oregon Low Emission Vehicles Program. In 2008, the ECO Program worked with 800 of the Portland area's largest employers to reduce about 50 million vehicle miles travelled, preventing about 10,000 pounds of air toxics from entering the air. The Vehicle Inspection Program tests over 500,000 vehicles every year in Portland and Medford and keeps over 170 tons of pollution per day out of the air. Oregon's Low Emission Vehicles Program requirements for new cars and trucks that began with the 2009 model year will reduce air toxics in Oregon between six and 11 percent by 2020.

Federal regulations that go into effect in 2011 will cut gasoline benzene levels in half and clean engine standards for gas and diesel vehicles will result in further decreases in air toxics. DEQ implements rules to limit vapor leaks from gasoline storage and loading. However, significant additional state and local regulatory and voluntary programs will be needed to achieve the air toxics health-based ambient benchmark concentrations.
​DEQ investigation of odor complaints is an attempt to identify the source causing the problem. If a source is identified, DEQ has several approaches for follow-up.

If a complaint about an industrial facility results in the discovery of a permit violation, the source must correct the violation. Violations of regulations or permit conditions may lead to enforcement with civil penalties designed to remove any economic benefit to the source from the violation and deter future violations. In instances where the complaint is not related to a violation, DEQ will work with the facility to determine if there are measures that can reduce the problem.

In cases where complaints are ongoing, DEQ has several options for follow-up. One option is to ensure that existing emission control systems that reduce odors are well maintained and operated. Another option is to encourage the facility to voluntarily take additional measures to reduce odors. A third option is to facilitate a good neighbor agreement, in which the facility commits to pursue additional measures to address neighbors' concerns. A fourth option is for DEQ and the facility to enter into a best work practices agreement, in which the facility commits to enforceable measures to reduce the nuisance. The elements of the agreement then become permit conditions.

If the source of the odor cannot be identified DEQ will coordinate with individuals, local businesses and various local officials to attempt to locate the source. DEQ sometimes determines that there is not enough information to do further investigation. When reporting an incident or filing a complaint to DEQ it is important to be as complete as possible in the description of its nature, location, intensity and frequency to aid the investigation.

​The Oregon Legislature eliminated the DEQ noise control program in 1991 as a cost-cutting measure. However, you can file a noise complaint in Portland with the City of Portland.


For information about industrial facilities DEQ regulates please visit

You can also find detailed information on chemicals released by each facility in the Environmental Protection Agency's Toxics Release Inventory Database.​


DEQ monitors for certain air quality pollutants, specifically fine particulate matter, also known as PM2.5 throughout the Portland Metro region.

Recent monitoring data has shown high particulate levels at the DEQ air monitor located in Hillsboro (one of two monitors in Washington County). While the region is not currently over the federal health standard for PM2.5, it is getting close and poor air quality could result in adverse health and economic impacts to the region and beyond. 

Currently, Washington County, the City of Hillsboro and other stakeholders are taking action to address air quality in their area.

PM2.5 is a mixture of extremely small particles and liquid droplets found in the air. PM2.5 can be inhaled deep into the lungs and can lodge there for weeks and months, aggravating asthma, heart disease, and other respiratory and heart conditions. The primary source of PM2.5 is from woodstoves, although cars, backyard burning, industry, and commercial activities can also contribute to PM2.5 levels.

File a pollution complaint online

Portland skyline