Outdoor Hydronic Heaters

States have identified outdoor hydronic heaters as a critical local air pollution issue. To support the states' work in this area, NESCAUM formed a workgroup to address a variety of issues concerning the unregulated emissions from these pollution sources. With funding and participation by EPA, the workgroup developed a model rule to promote common regulatory standards across state and local areas. The model rule is based on meeting existing federal air quality health standards set by the U.S. EPA.

A major aim of the rule is to meet current federal air quality standards for particulate matter (PM) that are based on PM’s extensively documented adverse health impacts to the heart and lungs. In order to achieve this goal, the model rule establishes emission limits and labeling requirements for new outdoor hydronic heaters and contains the following components for both new and existing outdoor hydronic heaters:

• setback requirements from property lines, structures, and homes
• stack height requirements
• distributor and buyer notification requirements