File No. 36481

This rule was published in the December 1, 2012, issue (Vol. 2012, No. 23) of the Utah State Bulletin.

Environmental Quality, Air Quality

Rule R307-208

Outdoor Wood Boiler Prohibition

Change in Proposed Rule

DAR File No.: 36481
Filed: 11/08/2012 02:18:08 PM


Purpose of the rule or reason for the change:

During the public comment period, the Division of Air Quality (DAQ) received numerous comments opposing the proposed rule. These comments were predominately from owners of outdoor wood boilers outside of the PM2.5 nonattainment area that were concerned that when their existing units expired, they would not be able to replace them. They also expressed concern that alternate fuels available to them are more expensive than wood.

Summary of the rule or change:

The rule was changed by removing the statewide ban on outdoor wood boilers and by adding a list of prohibited fuels; adding requirements for setbacks from schools, hospitals and day care facilities; establishing stack height requirements; adding new boiler labeling requirements; and in nonattainment areas, requiring those who wish to replace an existing unit in the future to register their existing unit with DAQ, and when they replace their existing unit, requiring them to replace it with a wood pellet outdoor boiler. (DAR NOTE: This change in proposed rule has been filed to make additional changes to a proposed new rule that was published in the August 1, 2012, issue of the Utah State Bulletin, on page 12. Underlining in the rule below indicates text that has been added since the publication of the proposed rule mentioned above; strike-out indicates text that has been deleted. You must view the change in proposed rule and the proposed new rule together to understand all of the changes that will be enforceable should the agency make this rule effective.)

State statutory or constitutional authorization for this rule:

  • Section 19-2-101
  • Section 19-2-104

Anticipated cost or savings to:

the state budget:

There may be adding costs to DAQ to administer this rule; however, costs should be minimal, so there are no anticipated costs or savings to the state budget.

local governments:

There are no new requirements for local governments; therefore, there are no anticipated costs or savings associated with this change in proposed rule.

small businesses:

These changes will now allow small businesses to sell certain types of outdoor wood boilers in Utah. However, since Utah is not a large market base for these units, the impact should be limited.

persons other than small businesses, businesses, or local governmental entities:

As this change in proposed rule now allows all persons to sell, purchase, install, or transfer an EPA Phase 2 outdoor wood boiler in certain parts of the state, there may be some costs or savings to persons other than small businesses, businesses, or local government entities; however, it is difficult to estimate what those would be.

Compliance costs for affected persons:

Minimal compliance costs will be incurred from the registration requirement. There will be costs for those wishing to replace existing outdoor wood boilers with new outdoor wood boilers, as they would have to be replaced with either an EPA Phase 2 qualified or a wood pellet outdoor boiler. These units are competitively priced, and the costs should be minimal.

Comments by the department head on the fiscal impact the rule may have on businesses:

Businesses will now be able to sell and install certain types of outdoor wood boilers in Utah; however, because Utah is not a large market base for outdoor wood boilers, the fiscal impact should be minimal.

Amanda Smith, Executive Director

The full text of this rule may be inspected, during regular business hours, at the Division of Administrative Rules, or at:

Environmental Quality
Air QualityRoom Fourth Floor
195 N 1950 W
SALT LAKE CITY, UT 84116-3085

Direct questions regarding this rule to:

  • Mark Berger at the above address, by phone at 801-536-4000, by FAX at 801-536-0085, or by Internet E-mail at

Interested persons may present their views on this rule by submitting written comments to the address above no later than 5:00 p.m. on:


This rule may become effective on:


Authorized by:

Bryce Bird, Director


R307. Environmental Quality, Air Quality.

R307-208. Outdoor Wood Boilers [Prohibition].

[R307-208-1. Purpose and Applicability.

R307-208 applies statewide and establishes a ban on outdoor wood boilers, also known as wood-fired hydronic heaters.


]R307-208-[2]1. Definitions.

The following additional definitions appl[ies]y to R307-208:

"Clean wood" means wood that has not been painted, stained, or treated with any coatings, glues or preservatives, including, but not limited to, chromated copper arsenate, creosote, alkaline copper quaternary, copper azole or pentachlorophenol.

"Commercial new outdoor wood boiler" means a new outdoor wood boiler with a thermal output rating greater than 250,000 BTU per hour.

"Outdoor wood boiler" means a fuel burning device also known as a wood-fired hydronic heater:

(1) Designed to burn wood or other approved solid fuels;

(2) Specified by the manufacturer for outdoor installation or installation in structures not normally occupied by humans; and

(3) Designated to heat building space or water via the distribution, typically through pipes, of a fluid heated in the device, typically water or a mixture of water and antifreeze.

"New outdoor wood boiler" means an outdoor wood boiler that commences operation on or after March 1, 2013.

"Sole source of heat" means the solid fuel burning device is the only available source of heat for the entire residence or business, except for small portable heaters.

"Residential new outdoor wood boiler" means a new outdoor wood boiler that has a thermal output rating of 250,000 BTU per hour or less.

"Unseasoned wood" means wood that has not been allowed to dry for at least six months.

"Wood pellet outdoor boiler" means an outdoor wood boiler with an automatic pellet feed mechanism.


R307-208-[3]2. Prohibition.

(1) Prohibited fuels. No person shall burn any of the following items in an outdoor wood boiler:

(a) Wood that does not meet the definition of clean wood;

(b) Unseasoned wood;

(c) Garbage;

(d) Tires;

(e) Yard waste, including lawn clippings;

(f) Materials containing plastic;

(g) Materials containing rubber;

(h) Waste petroleum products;

(i) Paints or paint thinners;

(j) Household or laboratory chemicals;

(k) Coal;

(l) Glossy or colored paper;

(m) Construction and demolition debris;

(n) Plywood;

(o) Particleboard;

(p) Fiberboard;

(q) Oriented strand board;

(r) Manure;

(s) Animal carcasses;

(t) Asphalt products;

(2) No person shall operate an outdoor wood boiler within 1000 feet of a private or public school, hospital or day care facility.

(3) Setback. A new residential outdoor wood boiler shall not be located less than 100 feet from the nearest property boundary line. A new commercial outdoor wood boiler shall not be located less than 200 feet from the nearest property boundary nor 300 feet from a property boundary of a residentially zoned property.

(4) Stack height. A new outdoor wood boiler shall have a permanent stack extending five feet higher than the peak of any roof structure within 150 feet of the outdoor wood boiler.

(5) [Beginning September 1, 2013, n]In areas other than those described in R307-208-5(1), no person shall sell, offer for sale, supply, install, purchase, or transfer an outdoor wood boiler after March 1, 2013, unless it is EPA Phase 2 qualified or a wood pellet outdoor boiler.


R307-208-[4]3. [Exemptions.]Visible Emission Standard.

[ (1) All persons who own or operate an outdoor wood boiler prior to October 4, 2012 shall comply with the following requirements to be exempt from the rule:

(a) Within 180 days of October 4, 2012, register the outdoor wood boiler with the director or local health district office;

(b) Operate the outdoor wood boiler in accordance with outdoor wood boiler manufacturer's instructions; and

(c)](1) Visible emissions for all outdoor wood boilers shall be limited to a shade or density no darker than 20% opacity as measured by EPA Method 9, except for the following:

([i]a) An initial fifteen minute start-up period[,]; and

([ii]b) A period of fifteen minutes in any three-hour period in which emissions may exceed the 20% opacity limitation for refueling.


R307-208-4. New Boiler Labeling.

(1) A permanent label shall be affixed to all new outdoor wood boilers by the manufacturer.

(a) The label material shall be durable to last the lifetime of the new unit.

(b) The label shall be affixed so that it cannot be removed.

(c) The label shall be affixed so that it is readily visible.

(d) The following information shall be displayed on the label:

(i) Name and address of the manufacturer;

(ii) Date of manufacture;

(iii) Model name and number;

(iv) Serial number;

(v) Thermal output rating in BTU per hour; and

(vi) Certified particulate emission rate in pounds per million BTU heat output.


R307-208-5. Particulate Matter Nonattainment and Maintenance Plan Areas.

(1) R307-208-5 applies in all regions of Salt Lake and Davis counties; all portions of the Cache Valley; all regions in Weber and Utah counties west of the Wasatch mountain range; in Box Elder County, from the Wasatch mountain range west to the Promontory mountain range and south of Portage; and in Tooele County, from the northernmost part of the Oquirrh mountain range to the northern most part of the Stansbury mountain range and north of Route 199.

(2) No person shall sell, install or resell an outdoor wood boiler commencing March 1, 2013, with the exception of persons who register an outdoor wood boiler under R307-208-5(3).

(3) Owners of an existing outdoor wood boiler wishing to replace it after March 1, 2013, shall:

(a) Register the existing outdoor wood boiler with the director by March 1, 2013;

(b) Replace the existing outdoor wood boiler with a wood pellet outdoor wood boiler; and

(c) Comply with the provisions of R307-208-2 and 3.

(4) Persons unable to meet setback requirements in R307-208-2(3) because of existing land use limitations must request a waiver from the director before installing an outdoor wood boiler. Such waiver must include written approval from surrounding neighbors within the setback areas described in R307-208-2(3).


R307-208-6. Air Quality Action and Alert Days.

(1) By March 1, 2013, sole sources of residential or commercial heating using an outdoor wood boiler must be registered with the director in order to be exempt from R307-208-6(2).

(2) No person shall operate an outdoor wood boiler on an air quality action or alert day as established under R307-302, except those that are registered with the director as sole source of heat.


KEY: air pollution, outdoor wood boilers, prohibition

Date of Enactment or Last Substantive Amendment: [2012]2013

Authorizing, and Implemented or Interpreted Law: 19-2-101; 19-2-104


Additional Information

The Portable Document Format (PDF) version of the Bulletin is the official version. The PDF version of this issue is available at The HTML edition of the Bulletin is a convenience copy. Any discrepancy between the PDF version and HTML version is resolved in favor of the PDF version.

Text to be deleted is struck through and surrounded by brackets (e.g., [example]). Text to be added is underlined (e.g., example).  Older browsers may not depict some or any of these attributes on the screen or when the document is printed.

For questions regarding the content or application of this rule, please contact Mark Berger at the above address, by phone at 801-536-4000, by FAX at 801-536-0085, or by Internet E-mail at