Air quality, noise & energy policies and procedures

Learn how to comply with air quality, noise, and energy regulatory requirements for your project. To ensure quality analyses, the Washington State Department of Transportation (WSDOT) provides standard practices and helpful tools. 

Air quality

Read Chapter 425: Air Quality of the Environmental Manual to understand the policy context for project-level air quality analyses. 


Projects in air quality maintenance or nonattainment areas must demonstrate conformity. Washington State has areas under maintenance plans for course particulate matter (PM10), fine particulate matter (PM2.5), and carbon monoxide (CO). Find general information about transportation conformity requirements at the Federal Highway Administration's (FHWA) Air Quality and FHWA Transportation Conformity sites and Washington-specific information below.

Carbon monoxide

For projects in CO maintenance areas, use WASIST, the Washington State intersection screening tool. Version 3.0 of the tool uses MOVES2014 (Motor Vehicle Emissions Simulator) emission factors and is approved by the US Environmental Protection Agency's Region 10. To request the tool, please contact Jim Laughlin,

Puget Sound and Vancouver areas no longer require CO conformity analysis as of October 2016.

Particulate matter 

Larger projects in particulate matter maintenance areas may meet the EPA description of a "project of air quality concern" and could require a hot-spot analysis. EPA offers direction on Project-Level and Hot-Spot Analysis on their website. Refer to the Appendix B of EPA’s “Transportation conformity Guidance for Quantitative Hot-spot Analysis in PM2.5 and PM10 Nonattainment and Maintenance Areas” for descriptions of projects that may and may not require PM hot-spot analysis. For help determining if your project may need a particulate matter hot spot analysis, contact Karin Landsberg,

WSDOT follows the Memorandum of Agreement - Fugitive Dust (pdf 22 kb) with Puget Sound Clean Air Agency on all projects within King, Kitsap, Pierce, and Snohomish counties. The Guide to Handling Fugitive Dust from Construction Projects (pdf 862 kb)from the Associated General Contractors of Washington provides additional information on fugitive dust best managemnt practices. 

Mobile Source Air Toxics (MSAT)

For MSAT analyses, WSDOT follows FHWA's interim guidance. If your project includes road segments with more than 140,000 average annual daily traffic, a quantitative MSAT analysis is required. 

Refer to the FHWA MSAT Frequently Asked Questions for additional information on how to complete an MSAT analysis. 


Project analysis request and checklist

The air quality checklist (pdf 12 kb) outlines documentation requirements for WSDOT review and approval and can help with project scoping. 

If you are working on a WSDOT project and need an air quality analysis, tell the Environmental Documentation and Permit Specialist assigned to your project. 



Read Chapter 446: Noise of the Environmental Manual to learn about the policy context for project-level noise analyses. 

The WSDOT Noise Policy (pdf 375 kb) describes the policies for project-level noise analyses.

  • Appendix 1 - Use of state funds (pdf 188 kb)
  • Appendix 2 - Improving the noise environment when standard options aren't available (pdf 460 kb)
  • Appendix 3 - Noise analysis and mitigation (pdf 62 kb)
  • Appendix 4 - Noise studies (pdf 59 kb)
  • Appendix 5 - Hard shoulder running project guidance (pdf 695 kb)

The Traffic Noise Model (TNM) Guidance (pdf 743 kb) explains how to use the TNM model for WSDOT projects.

Information on noise requirements for transit or rail projects is available from the Federal Transit Administration and the Federal Rail Administration


Project analysis request and checklist

Use the noise report checklist (pdf 96 kb) to make sure you have included all information needed for WSDOT's review and approval. The checklist can also help with project scoping. 

The noise report template (doc 603 kb) provides an outline and standardized background text to ensure your project documentation meets WSDOT criteria.

If you are working on a WSDOT project and need a noise quality analysis, contact Jim Laughlin,


Qualified noise professionals

Lead authors on WSDOT noise studies must have completed the National Highway Institute (NHI) Highway Traffic Noise course, or equivalent as determined by WSDOT. Our list of qualified noise professionals (pdf 84 kb) includes the names and contact information of consultants and WSDOT staff that have met this requirement. If you have taken the course, but are not listed, contact Jim Laughlin,, with a copy of the Certificate of Training from NHI to verify qualifications.


Nighttime noise variances

If your WSDOT project requires work at night, tell the Environmental Documentation and Permit Specialist assigned to your project. Find additional information on our Local permits & approvals page.


Underwater noise monitoring

WSDOT's Biological Assessment guidance provides information to address underwater noise impacts.

Use the Fisheries Hydroacoustic Working Group's (FHWG) Underwater Noise Monitoring Plan template (doc 319 kb) to standardize collecting and reporting underwater noise monitoring data. For additional background on the template, see the FHWG template cover Letter (doc 22 kb). 



Read Chapter 440: Energy of the Environmental Manual to learn about the policy context for project-level energy analyses.

Only projects being evaluated at the environmental impact statement (EIS) level require an energy analysis. Use the energy report checklist (pdf 96 kb) to make sure you have included all information needed for WSDOT's review and approval. The checklist can also help with project scoping. 

Our Project-Level Greenhouse Gas Evaluations under NEPA and SEPA (pdf 293 kb) describes WSDOT's approach to addressing greenhouse gases in project documentation. All WSDOT projects must follow this approach. 

Find more information about our approaches to addressing climate change on our climate change page