Unvented room heaters and unvented fireplaces are not permitted in any building or structure regulated under the “Vermont Fire & Building Safety Code – 2005”. This state amendment is intended to prevent a build up of carbon monoxide from fuel burning appliances in normal room size areas. It is not the intent of the code to prohibit unvented heaters that are designed for use in large open areas in industrial buildings or buildings of similar size. Additional details are provided under the state amendment for NFPA 1:22.214.171.124.4. Single-family owner occupied dwellings, family residence registered day care and certain buildings on working farms are nor regulated under the “Vermont Fire & Building Safety Code – 2005”.