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New Wood Heater & Boiler Regulations (Act 50)

On June 10, 2019, Governor Scott signed into law Act 50 which establishes milestones for the regulation and oversight of certain Industrial, Commercial and Institutional (ICI) wood heaters (a.k.a. boilers) in the State of Vermont.

Through this session law the Legislature has charged the Air Quality & Climate Division (AQCD) with amending the state’s air pollution regulations that apply to ICI wood boilers using cordwood, wood pellets or wood chips as fuel.  These changes will include rules that allow for methods, other than EPA certification, of demonstrating compliance with the applicable air quality rules and standards.  An example of another method is to use the test results from the European test method “EN 303-5”. While the air quality regulations are being amended, the legislature has allowed for other provisions, discussed below, to allow the sale and installation of certain ICI wood boilers.

The AQCD has developed a certification process and application (see link below) to review performance data for individual models of ICI wood boilers based on alternative testing methods, such as EN 303-5.  This process is applicable to ICI wood boilers rated at up to 2.5 MMBtu/hr heat output (this is roughly 3.0 MMBtu/hr heat input). For a unit to be certified for sale and installation in Vermont, the review must determine that the wood boiler model meets the applicable EPA emission standards.  Existing units certified by the U.S. EPA for the type of wood fuel the unit is proposed to burn (e.g. pellets or chips), do not need to be certified by Vermont.  Manufacturers or installers (on behalf of the manufacturers) may submit an Application for Certification of Industrial, Commercial or Institutional Wood Heater for each specific wood boiler model that they are seeking to have certified by Vermont through this interim process.

For any sale of an ICI boiler, with a rated heat output of 2.5 MMBtu/hr or less, sellers and distributors of ICI wood boilers must notify the buyers, prior to any sale or lease agreement, of requirements regarding what fuels may be used in the boiler as well as operating & maintenance requirements.  A standard notice form is available from the AQCD. A copy of the signed notification must be sent to the AQCD at this mailing address:

Vermont Air Quality and Climate Division
Davis Building - 4th Floor
One National Life Drive
Montpelier, VT 05620

Note that wood boilers larger than 6.5 MMBtu/hr heat input (this is roughly 5 MMBtu/hr heat output) have been and continue to be required to obtain a construction permit by the AQCD.  Wood boilers with a rated heat output greater than 2.5 MMBtu/hr heat output, but less than ~ 5 MMBtu/hr heat output are currently not required to be certified by the AQCD or required to obtain a construction permit by the AQCD.