SACRAMENTO METROPOLITAN 

AIR QUALITY MANAGEMENT DISTRICT

For Agenda of October 25, 2007

To: Board of Directors 

 Sacramento Metropolitan Air Quality Management District 

From: Larry Greene, Air Pollution Control Officer 

 Sacramento Metropolitan Air Quality Management District 

Subject: New Rule 421, MANDATORY EPISODIC CURTAILMENT OF WOOD AND 

OTHER SOLID FUEL BURNING 

Recommendations 

1. Determine that the adoption of Rule 421 is exempt from the California Environmental 

Quality Act (CEQA); 

2. Decide whether to include one or more of the options in the proposed rule; and 

3. Approve the attached resolution adopting Rule 421. 

Executive Summary 

Proposed Rule 421, which was heard by the Board at the September 2007 meeting, prohibits 

wood or other solid fuel fires and use of fireplaces and wood or pellet stoves and inserts on 

days forecast to exceed the federal health standards. At the September hearing, the Board 

directed Staff to prepare the following additional options: 1) a voluntary program element, 2) a 

one year exemption for certified devices, 3) exempting certified devices from some mandatory 

no burn days, and 4) exempting certified devices from the rule without limitation. The Board 

also continued the public hearing to the October meeting. 

Staff has analyzed the impact of the new options on our progress toward attaining the federal 

PM2.5 standard. The first three options may provide for attaining the federal PM2.5 standards, 

however, there is a smaller margin of safety for meeting the standards with options 2 and 3. 

Staff’s analysis suggests that if certified stoves are exempt from Rule 421, Sacramento County 

may not meet the federal health standards by 2012. It is likely that the District will need to 

regulate other sources to replace the 2.5 tons per day of emission reductions that will be lost by 

exempting certified devices. 

Attachments 

The table below identifies the attachments to this memo. 

Item Attachment Page Number 

Board Resolution A 8 

Proposed Rule 421 B 11 

Options for Rule 421 C 16 

Comments Received after September Hearing D 28 

September Board Package E 67 
Board Memo 

Rules 421, MANDATORY EPISODIC CURTAILMENT OF WOOD AND OTHER SOLID FUEL BURNING 

October 25, 2007, Page 2 

Background 

Three issues were discussed at some length during the September Board meeting: outreach, 

estimates of the number of devices and related emissions, and exemptions for EPA certified 

devices and pellet stoves. This document will discuss only those issues, but additional 

information about the proposed Rule 421 can be found in the September Board materials 

(Attachment E.) 

Outreach 

Rule 421 will rely on the existing public outreach structure well established through the Spare 

the Air program. The program will be called Check Before You Burn. Our Communications 

office and public relations consultant have prepared an outreach strategy that will use hundreds, 

if not thousands, of partnerships already in place to educate the community, including ethnic 

and grass roots community groups. 

Estimates 

Staff evaluated the information presented by Duraflame at the September hearing. When the 

industry data sources are used, the wood smoke emissions inventory is slightly higher than the 

inventory prepared by the California Air Resources Board, but within the range of staff's original 

estimates. The industry figures were used for the calculations and the estimate of wood smoke 

emission reductions that would be needed for attainment in this Board letter. 

Certified devices and pellet stoves 

In the discussion on certified devices and pellet stoves, several issues were raised including: 

1) whether Rule 421 conflicts with the District’s incentive program which encourages 

replacement with certified devices and pellet stoves, while Rule 421 prohibits their use on some 

days; and 2) whether emissions from certified devices and pellet stoves are small enough to be 

exempted without interfering with attainment goals. 

The District began the incentive program at the same time staff was preparing Rule 421 for 

adoption. As originally conceived, Rule 421 would have banned all wood fires on days when air 

quality was predicted to exceed federal health standards. Since the Rule would have prohibited 

use of the devices on no-burn days, encouraging the purchase of the devices through the 

incentive program did not conflict with clean air goals. 

If certified and pellet devices are exempt from the no-burn days, the incentive program will have 

the unintended effect of increasing emissions on no-burn days, when air quality is at its worst. 

At the outset, the exemption will allow the emission of 2.5 tons of PM2.5 per day from the 

existing 45,196 certified and pellet stoves already installed within the district1

. These emissions 

will increase over time, because the incentive program will encourage people to shift away from 

devices that would have been subject to the ban and toward installation of devices that will be 

allowed to operate on no-burn days. To date, the incentive program has replaced 52 uncertified 

devices and 195 fireplaces with certified devices and pellet stoves. 

 

1

 Total number of wood stoves is from 2004 American Housing Survey. The percent of stoves certified is from 

Amanda Aldridge, EPA (10/3/07). Number of pellet stoves is from US Census Projection. 
Board Memo 

Rules 421, MANDATORY EPISODIC CURTAILMENT OF WOOD AND OTHER SOLID FUEL BURNING 

October 25, 2007, Page 3 

The interplay between a Rule 421 exemption and Rule 417 may also lessen the emission 

reduction potential of Rule 421. Rule 417 prohibits the sale and installation of uncertified 

devices or open hearth fireplaces. That rule could result in the installation of more certified and 

pellet stoves (in addition to natural-gas fired stoves). Since these devices would be allowed to 

burn on no-burn days, the level of uncaptured emission reductions will be more than the current 

2.5 tons of missed reductions. 

Between the incentive program and Rule 417, staff has estimated that emissions from new and 

replacement wood-burning devices will increase annually by 0.2 tons per day on no-burn days. 

If these emissions occur, the staff analysis indicates that the district will not meet the PM2.5 

attainment goals. 

In addition, based on the usage information obtained by staff, certified devices are used more 

often than fireplaces (28 days per year versus 43 days per year). As the number of these 

devices increases, there is a risk that the number of no-burn days will increase because people 

will be burning more frequently. 

Moreover, staff has calculated that to achieve the same reductions achieved under an allinclusive no-burn rule, the area would have to replace over 60,000 uncertified devices and open 

hearth fireplaces with certified or pellet stoves. Since this replacement rate is unrealistic, the 

District will have to look at other regulations that could replace the 2.5-plus loss in emission 

reductions. It is important to note we have not yet identified sufficient reductions to offset the 

entire 2.5 tons, either individually or collectively. A more comprehensive search may identify 

additional strategies. The potential programs identified to date include: 

Regulations Potential PM 

Emission reductions 

(tons/day) 

Controls for agricultural and non-agricultural open burning, including 

residential burning of vegetative waste (currently allowed in parts of 

southern Sacramento County) 

0.325 

Controls for fugitive dust from bulk materials storage and handling 

(e.g. aggregate plants or animal silage) 

Unknown 

Design restrictions to reduce fugitive dust from new and modified 

paved roads 

0.004 

Control of fugitive dust from agricultural sources such as tilling, off-field 

operations, paved and unpaved roads, and livestock operations 

0.03 

Control of chipping and grinding operations, and co-composting with 

biosolids and/or manure 

Unknown 

More stringent control efficiency requirements for PM control devices 

such as baghouses, wet scrubbers, and electrostatic precipitators 

(e.g. concrete batch plants, cabinet shops, and wood processing 

operations) 

Unknown 

Summary of Proposed Rule and Options 

One of the most critical aspects for the success of this rule is public education. Residents in 

Sacramento County already hear no burn announcements for San Joaquin County. Local 

meteorologists have provided information on the San Joaquin Valley’s program during weather 
Board Memo 

Rules 421, MANDATORY EPISODIC CURTAILMENT OF WOOD AND OTHER SOLID FUEL BURNING 

October 25, 2007, Page 4 

forecasts for several years. Consistent media messaging with San Joaquin will decrease 

confusion for both the public and the meteorologists that we will be relying on to assist us in 

getting out our no burn messages. In addition, having consistent graphics and messages will 

improve the likelihood of meteorologists broadcasting our information. San Joaquin uses the 

following graphics and messages in their “Check Before Your Burn” program: 

 GOOD or MODERATE AIR = 

 Burn Cleanly 

 AIR UNHEALTHY FOR 

 SENSITIVE GROUPS = 

 Wood Burning Discouraged 

 UNHEALTHY AIR = 

 Wood Burning Prohibited 

At the October hearing, the Board of Directors could choose to adopt proposed Rule 421, 

including the financial hardship exemption, or adopt a revised Rule 421 under one or more of 

the options discussed below. The benefits and disadvantages of each option are also 

discussed. 

Proposed Rule 421 without any options 

The original proposed Rule 421 can be consistent with the graphics and messaging already in 

use by San Joaquin. The District would rely on the “Please Burn Cleanly” and “Wood Burning 

Prohibited” graphics and messages for this rule. 

Option 1 – Voluntary No Burn 

This option adds a voluntary no burn component. Voluntary no burn days would be called 

below the federal health standards in Rule 421 that trigger mandatory no burn days. Adding this 

component would make proposed Rule 421 most consistent with San Joaquin Valley’s no burn 

rule. On voluntary no burn days, wood burning would be discouraged. Those that choose to 

burn would be advised to burn cleanly, preferably in a certified device or pellet stove. Two 

thresholds are proposed; 25 micrograms per cubic meter of air (μg/m3

) which is estimated to 

result in 24 voluntary no burn days (in addition to the 23 mandatory no burn days), or 30 μg/m3

, 

which leads to 8 voluntary days. Additional days may decrease compliance rates if the public 

gets oversaturated by the requests or defies the requests because they perceive it as too 

frequent. All three of San Joaquin’s graphics and messages could be used for this rule. 

Option 2 – 1 year exemption 

This option adds a limited exemption for EPA certified devices and pellet stoves that do not 

produce visible smoke. There are two alternatives proposed. Under the first, the exemption 

expires in one year unless the federal standard is met (using 2007/2008 burn season data). 

Under the second, the exemption expires unless the Board extends it. One year is used 

because attainment must be demonstrated during 2009, 2010, and 2011, to avoid requirements 

associated with nonattainment, including the additional regulations noted above. 

If certified devices and pellet stoves are exempted from the rule, then their emissions (2.5 

tons/day and growing by 0.2 tons/day each year) would contribute to high particulate 

concentrations on poor air quality days. Under the first exemption, if Sacramento meets the 

health standards with emissions from certified devices and pellet stoves, then the exemption 

would continue. Weather conditions, which vary from year to year, have dramatic effects on air 
Board Memo 

Rules 421, MANDATORY EPISODIC CURTAILMENT OF WOOD AND OTHER SOLID FUEL BURNING 

October 25, 2007, Page 5 

quality. Meeting federal health standards during the first year doesn’t guarantee that the 

exemption would not contribute to nonattainment in future years. The second exemption allows 

the Board to consider any reason for extending the exemption. 

San Joaquin’s graphic and media messaging for a no burn day would require changes to be 

consistent with exempting devices from the “Wood Burning Prohibited.” 

In addition, media messaging and outreach materials would change if the exemption expires. 

This will add costs to outreach efforts and may cause some confusion. This version of the rule 

may help meet the federal health based standards, particularly if it expires after one year. 

Option 3 – 2-stage mandatory no burn program 

This option is a two stage mandatory no burn program. During a first stage mandatory no-burn, 

EPA certified devices and pellet stoves that do not produce visible smoke would be exempt. A 

first stage no burn day would be called if air quality is forecast to exceed the federal health 

standards, but is not likely to exceed 40 μg/m3

. During the second stage no burn, above 40 

μg/m3

, all wood burning would be prohibited. 

San Joaquin proposed a two stage program at a public workshop, but after considering 

comments received, chose not to implement a two stage mandatory program. This option has a 

greater potential for confusion on part of the media and the public. Because certified devices 

are prohibited from operating if air quality is forecast to exceed 40 μg/m3

, staff estimates that 

this option may meet attainment goals and avoid other regulations. However, continued 

emissions growth from certified devices and pellet stoves may result in future nonattainment 

designation. Staff estimates that emissions from certified devices and pellet stoves may 

contribute to nonattainment levels in about ten years. 

The Hearth Patio and Barbeque Association supported this option, provided the first stage is 

called at 20 or 25 μg/m3

. Staff is not recommending this because: 1) staff could not identify a 

health related basis for selection of a threshold other than the federal health standards, and 2) 

starting with a program that has significantly more mandatory no burn days is more likely to 

increase public frustration and resulting non-compliance rates. 

San Joaquin’s graphic and media messaging for no burn days would not be able to be used 

because it would not be consistent with having a two-stage “Wood Burning Prohibited.” 

Option 4 – exemption without expiration date 

This option adds an exemption, without an expiration date, from the mandatory no-burn rule for 

EPA certified devices and pellet stoves and inserts that do not produce visible smoke. 

Fireplaces and uncertified wood burning would be prohibited if federal health standards are 

forecast to be exceeded. 

The lost emissions reductions from exempting certified devices will likely cause us to fail to 

meet federal health standards. 

San Joaquin’s graphic and media messaging for a no burn day would not be able to be used 

because it would not be consistent with exempting devices from the “Wood Burning Prohibited.” 
Board Memo 

Rules 421, MANDATORY EPISODIC CURTAILMENT OF WOOD AND OTHER SOLID FUEL BURNING 

October 25, 2007, Page 6 

Environmental Review and Compliance 

Rule 421 was created as part of the response to the requirements of Senate Bill 656 that the 

District implement cost-effective control measures for particulate matter emissions. Staff finds 

that the proposed rule is exempt from the California Environmental Quality Act as an action by a 

regulatory agency for protection of the environment (Class 8 Categorical Exemption, Section 

15308 State CEQA Guidelines) and because it can be seen with certainty that there is no 

possibility that the activity in question may have a significant adverse effect on the environment 

(Section 15061(b)(3), State CEQA Guidelines). 

California Public Resources Code (Section 21159) requires an environmental analysis of the 

reasonably foreseeable methods of compliance. The proposed rule will not increase emissions 

and will not cause any significant adverse effects on the environment; therefore the 

Environmental Coordinator has concluded that no environmental impacts will be caused by 

compliance with the proposed rule. 

Conclusion 

Proposed Rule 421 will reduce emissions from the single largest PM2.5 emissions source, 

which was largely unregulated in the past. It will also reduce the serious health effects of 

wintertime particulate pollution, potentially avoiding some consequences from a federal 

nonattainment designation, and satisfy the requirements of state law (Health and Safety Code 

Section 39614). 

Proposed Rule 421 provides the simplest, most easily understood rule with appropriate 

exemptions to avoid undue burdens on the public. 

Option 1, adding a voluntary no burn element to proposed Rule 421 would be most consistent 

with the San Joaquin Valley program and is consistent with the District’s incentive program. 

Option 2, provides a one year exemption for certified devices. This provides an opportunity to 

test impacts from exempting certified devices. However, this option gives less certainty that the 

District will meet federal health standards and allows the exemption to be automatically 

extended even if air quality improvements are primarily related to uncharacteristically good 

weather. It also causes a conflict between the District's current incentive program and air quality 

goals because it increases the number of polluting devices operating when federal health 

standards are exceeded, because certified devices pollute even if they don't emit visible smoke. 

Option 3, with a staged no burn program that exempts certified devices from the first stage, 

provides the marketing advantage requested by hearth products manufacturing representatives 

and provides for attainment with a small, but declining, margin of safety. This option also causes 

a conflict between the District’s incentive program and air quality goals by increasing the 

number of polluting devices operating when air quality levels exceed the federal health 

standards and may cause confusion because of differences in the media message. 

Option 4 adds an exemption, without an expiration date, for certified devices and pellet stoves. 

This option also causes the incentive program conflict described previously, results in additional 

adverse health impacts, and is not likely to lead to attainment, thereby potentially triggering 

additional controls on other businesses.