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The City of Portland, Oregon

Office of Management & Finance

Trusted partner, creating smart solutions for the City and our community.

main: 503-823-5288

Revenue: 503-823-5157

1120 SW 5th Ave, Room 901, Portland, OR 97204

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Clean Air Construction

Diesel pollution is presently at unhealthy levels in the Portland Metro area, with diesel particulate matter (PM) emissions over 10 times state health benchmark levels. Well over 65% of those emissions come from nonroad equipment.  Although newer diesel engines are fitted with pollution controls that minimize diesel PM emissions (due to federal regulations), older dirty diesel engines are still prevalent due to their long lifespan. To address this issue and improve air quality in the Portland Metro area, the City of Portland, Multnomah County, Port of Portland, Metro, Washington County, Clackamas County, and Trimet are working together to reduce diesel PM emissions from publicly funded construction projects.  To date, the City of Portland and Multnomah County have adopted Clean Air Construction requirements for their construction contracts valued over a specified dollar threshold (the threshold varies by agency).  The primary goals of this regional collaboration is to 1) reduce deadly diesel pollution levels in the Portland Metro area; and 2) set a common set of requirements and program elements so as to minimize administrative burden on contractors and participating agencies.

This website contains information for the public and contractors regarding the regional Clean Air Construction initiative and resulting requirements for publicly funded construction projects.  There are many program elements still in development and information on this website will be updated as implementation elements are finalized.


Oregon Non-Road Diesel Emission Inventory

Oregon DEQ commissioned a non-road diesel emission inventory, which was completed in April 2020

Protect and Improve Air Quality to Prevent High Mortality Rates from Future Pandemics

How work on improving air quality helps makes our communities more resilient

Clean Air Construction Requirements

Clean Air Construction requirements applicable to construction projects funded by the public agencies that have adopted the CAC requirements

Clean Air Construction Flyer - English

Overview of clean air construction requirements

Clean Diesel Grants

Information on grant programs focused on reducing harmful diesel emissions

Diesel Pollution - Bad for Oregon's Health

Multnomah County fact sheet about health impacts of diesel pollution

Clean Air Construction FAQs

Frequently Asked Questions related to the Clean Air Construction initiative

EPA Nonroad Emission Ratings/Tiers Chart

EPA Emission Rating/Tier by Engine Model Year and Horsepower Range

Clean Air Construction Definitions

Definitions for terms and acronyms related to the Clean Air Construction requirements and program

Example 5 minute limit idling sign

example of 5 minute idling limit sign or sticker-decal