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Wood Preserving Area Sources: National Emission Standards for Hazardous Air Pollutants (NESHAP)

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Rule Summary

Wood preservation is the pressure or thermal impregnation of chemicals into wood to provide effective long-term resistance to attack by fungi, bacteria, insects, and marine borers. The wood preserving industry consists of facilities that treat wood such as lumber, ties, poles, posts, or pilings with a preservative.

The key pollutants EPA regulates from wood preserving sources include, chromium, arsenic, dioxins, and methylene chloride. 

The standard has two separate requirements, which include equipment requirements and management practices. For example, facilities using a pressure treatment process are required to use a retort or similarly enclosed vessel when involving any wood preservatives containing chromium, arsenic, dioxins, or methylene chloride. Facilities using a thermal treatment process involving any wood preservatives containing chromium, arsenic, dioxins, or methylene chloride are required to use process treatment tanks.

See the regulations in the section below for more details.  

Rule History

03/28/2008 - Direct Final Rule with technical corrections

07/16/2007 - Final Rule

04/04/2007 - Proposed Rule

Additional Resources

Fact Sheets: Air Toxics Standards for Area Sources in Seven Industry Sectors

Summary of Regulations Controlling Air Emissions for the Wood Preserving Industry: National Emission Standards for Hazardous Air Pollutants (NESHAP) Subpart QQQQQQ Brochure

View the supporting documents in the docket folder to find additional related documents to this rule.