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Heating Safety: The Smoke Check Rule

We have spent a long time helping develop non-suicidal wood heat.  Now as a volunteer fire fighter, Erica gets to see what happens when a chimney fire or electrical fire takes hold of a rural home. 

House fires are depressing.  Let's consider how we can avoid them.

Good Operator Practices: Any chimney sweep or stove installer will encourage you to
- read the instructions
- follow the instructions
- get your wood in early, and keep it seasoned and dry
- calibrate your operating skills by going outside to check your chimney.  If it's smoking, do something differently.
- inspect annually.  If you don't know the signs of a chimney fire past, present, or future, hire a good chimney sweep who does.

Proper Construction and Maintenance: 
Build to code or better.  Build to local best practice or better.  BOTH.

Even if you don't follow building code in your area, it's worth reading the IRC codes before doing owner-builder work.  They are available for free online, both the national /international version and many states' adapted versions.  Aside from the occasional well-intentioned guesswork or special-interest artifacts, the bulk of the codes are solid, time-tested, best-practice, and they are generally written as a minimum standard for a competent, professional builder. 

Willful ignorance is pitiful in an owner, and shameful in a builder-for-hire.  When ethical professionals build "outside the box," we do so fully informed, for good reason, and with full disclosure. 
I always want my own home, and those I serve, to be at least as safe, healthy, durable, and livable as an up-to-code home.

"When you learn your high school physics, you can sit at the big boys' table." - Joseph Lstiburek, https://buildingscience.com/documents/insights/bsi-065-i-was-younger-then

Improvised "Chimney" = Fire Trap
If you decide to DIY or "upgrade"a chimney  instead of doing a standard, class-A manufactured chimney, please consult a pro.  A local chimney sweep can inspect, or even better, check your plan before installation.  Physicists and professional builders often get confused about exactly what conditions cause a chimney stall, backdrafting, or creosote formation.  This is a dangerous field for DIY; the consequences of ignorance can be swift and lethal.

Proper Installation and Clearances:  Follow the manufacturer's instructions.  Some metal chimney parts can have 2" clearance, others may require 9" or 18".  Some clearances can be reduced by well-configured heat shielding; in any case, always allow at least the minimum clearance you would need with excellent heat shielding, and leave the areas behind any heat shielding accessible for inspection and cleaning.

Common Clearances 3 feet / 12 Inches: For space heaters without instructions: including non-certified or older wood-burning stoves, gas logs, and portable gas/electric radiators: the NFPA rule of thumb is 36" (3 feet, about 1 meter) from combustibles.  In some cases this can be reduced to 18" with good heat shielding, or as little as 12" with excellent heat shielding.  A significant number of house fires can be traced to combustibles (kindling, clothing, clutter) too close to a space heater. 
For candles and other smaller heat sources, the rule of thumb is 12 inches.  Decorations and drapes should be at least 12" back from the candle, including their range of motion if they are caught in a draft or rumpus.

Cat, Rat, and Vacuum Clearances: If a mouse can get in, make it big enough to send the cat or vacuum hose after it.


Safe Homes, Healthy Communities, and Fire Protection with the EPA De-Funded:

The February 2017 de-funding of the EPA opens the door to a proliferation of all sorts of public safety issues that were formerly inspected by EPA employees. 
Local emergency responders, public safety officials, and community planners may be looking for a way to replace their EPA inspector's function(s) in order to keep our people safe.
For my own fire district, I am concerned about possible water contamination or diversion leading to unsafe/unreliable wells, or exacerbating drought conditions and flash flooding; possible reductions in water availability at common sources used by fire crews such as private/public lakes and creeks; and of course the direct fire dangers of unchecked bad operators.  Smoke is not just an air quality issue; it's an early warning sign of wood stove abuse that, unchecked, often leads to catastrophic chimney fires.
For myself personally, and future generations, I'm also concerned about this window allowing lasting/permanent damage such as mine runoff and chemical contamination, but these issues are harder to discuss with the general public.
My personal opinion is that if you can't read smoke sign, and have no experience installing heaters in actual existing structures, you probably should not be writing rules for those who do.  However, de-funding the EPA throws the baby out with the bath water.  The current situation opens the door to a lot more "Freak Shows of Flaming Death."  (Thanks again for that memorable phrase, Paul Wheaton!)

Here is my proposal for a workable stop-gap solution, derived from international colleagues and personal experience.

Community Safety Check for Solid Fuel Heaters

This is a DRAFT proposal, version 1 dated March 6, 2017.

Smoke-Sign Safety Check: Draft 1 Summary

1) Not more than 20 minutes of visible smoke. 
This corresponds to current EPA testing protocols; can be documented by anyone with a cell phone camera; can be reviewed by minimally-trained responders who can tell problem smoke from clean steam/exhaust either in person or by video, to determine if an inspection is needed.

2) Safety inspection - this could be done by a licensed chimney sweep, fire investigator, or any qualified local inspector confirmed by their peers as capable of reading smoke sign and building details at an expert level.  (Elected/appointed/volunteer civil servants are not intrinsically qualified to approve such experts, but may run negative screens such as a background check.)

__Chimney(s) safe and operable, no signs of past or future chimney fires

__Heater(s) safe and operable, no signs of over-fire, under-fire, or ill repair

__Clearances appear adequate (if not, mark with 165 F calibrated thermal crayon for follow-up)

__Operator demonstrated acceptable skills and practices for <20 minute standard of clean, safe fire (check night-time burn practices if applicable)

If any points do not pass initial inspection, schedule a follow-up inspection in 40 days, or at an appropriate point in the upcoming heating season.

3) Follow-up inspection: in 40 days, repeat initial inspection, with special attention to previous problems.  Because operator practices may have changed, re-inspect all points to ensure no new problems have inadvertently been started.  Crayon-checked clearances should be re-inspected after one full heating season, if possible.

A successful inspection on the 2nd or 3rd try can be turned over to the owner/operator, with a certificate such as the one at the bottom of this page.  For owners who passed on a 2nd or 3rd inspection, encourage them to voluntarily re-inspect every 1 to 3 years with a qualified expert, until good and safe practices become second nature.

4) Repeat Offenders / Non-compliance / 3rd strike

Operators not able to safely heat with solid fuels may be a danger to themselves and others.  Yet keeping one's family warm in the winter is a basic human right.  Communities may need creative problem-solving to encourage voluntary compliance.  Existing laws and rules about criminal negligence and arson will generally be sufficient to prosecute malicious non-compliance. 

In between may be tough-love policies about when to engage social services, issue cease-and-desist orders, or combine incentives and penalties to speed unsafe operators into a safer situation.

This is a DRAFT proposal, version 1 dated March 6, 2017.
It is intended for consideration by other heating experts and public safety organizations
following the February 2017 de-funding of the EPA
The author, Erica Wisner, is a 20-year public science educator, freelance R&D innovator in sustainable heating and cooling, author of several books including the Rocket Mass Heater Builders' Guide, and a volunteer fire fighter in Okanogan County, Washington.

Please send your thoughts on this draft to: [email protected]
Please include the phrase "Smoke Check" in the topic or body of the message, if possible.

Expanded Notes on Draft 1:

The following elaborate notes discuss why, how, and other details of the summary above.

Smokeless Fox Stove

This is a "fox stove," dug into the ground with a shovel, boiling a pot of water without visible smoke.
If you can't do this, there might also be other things you don't know about fire.

1) Smoke Check: <20 Minutes of Visible Smoke.

Regardless of the make or model, a solid fuel heater being operated so that it regularly produces over 20 minutes of visible smoke is in danger of causing a chimney fire, not to mention air-quality hazards for respiratory and cardio health.
Intelligent citizens, using only their naked eyes, can be trained to see the difference between clean/white steam exhaust, and particulate smoke with blue, grey, or yellow tints.  (Takes less than 20 minutes to train most folks on this level of smoke reading.  Most fire responders, chimney sweeps, and solid-fuel professionals are already trained.)

Trained personnel can verify >20 minutes of visible smoke, with photo or video evidence, to check whether a home owner or renter may be causing a smoke/chimney fire hazard.  Concerned neighbors may submit a complaint by including video evidence of 20+ minutes of smoke.  Trained smoke readers could document obvious cases (column or trail of smoke) with about 5 minutes of video that allows an expert witness to reasonably estimate wind and weather conditions.

Tool: Cell Phone or Camera
Qualifications: Minimal
Procedure: Trained smoke-readers, verify citizen complaints before requesting an inspection.

Why 20 Minutes? 
Achievable: We believe that 20 minutes of visible smoke is an achievable limit by any skilled operator with a primitive stove, or an unskilled operator carefully following the instructions for a good-quality certified stove.  In our own work, we have several 'primitive' stoves we can build with a shovel that achieve less than 5-minute smoke signatures.  This performance is achievable by a wide range of local methods, skill levels, and economic levels.
Rigorous: The 20-minute standard is compatible with recent EPA testing procedures, which typically start the test about 15 minutes after re-loading fresh fuel.  While the highest EPA particulate standards may be more rigorous under lab conditions, in practice many EPA-II certified stoves produce visible smoke under actual operating conditions, due to operator error, wear and weather, or deliberate work-arounds by owners seeking overnight heat through smoldering, banked, or damped-down fires.
Affordable and Verifiable: Besides allowing good operators to use low-end stoves with care, the 20-minute standard is inspection-friendly.  A full 20-minute smoke-check can happen within a 30-minute inspection visit, limiting the costs and equipment needed to verify compliance.  20 minutes is also a bit long to spend in one place on your average dog-walking excursion, and may be just long enough to discourage nuisance harassment by over-zealous neighbors.
Common and Simple Standard: There are reasons to prefer one widely-used standard, endorsed by industry and public service organizations.  Common standards encourage compliance, reduce confusion, and limit the problems that may be created by well-intentioned but non-expert rule-makers at all levels of governance. (Simple, effective standards also reduce the temptation for corrupt officials or special interests to advocate burdensome regulations targeting competitors.)
Sustainable and Safe: Renewable solid fuels are an important energy resource for many communities.  Reducing the buildup of small fuels in our forests is a public safety issue. By encouraging good wood heat practices, we preserve skills and community partnerships that benefit current and future generations.

- Local Exemptions: As Needed
In some communities, the 20-minute standard may not be considered necessary (remote rural, sparse population, overabundance of poor fuels, no air stagnation zone, etc). 
As they already do, individual jurisdictions may create standing exemptions for grandfathered-in owners, religious ceremonies, antique stoves, humanitarian exemptions for subsistence heating and cooking needs.  Most areas will likely maintain existing exemptions for dirty but popular practices like agricultural burning, incinerators, certified outdoor boilers.  Exemptions are a flexible tool to suit the needs of the community.
   "In my personal and professional experience," says author Erica Wisner, "properly-authorized exemptions are less likely to cause confusion, unintended consequences, or bad sportsmanship than local re-writing of a common standard."

- Local Add-On Requirements or Recommendations: Caution Advised
Certain areas could also add on additional standards, such as EPA certification, but proceed with extreme caution.  High-density, wealthy populations often include amateur "there oughtta be a law" enthusiasts who eagerly donate time to working groups promoting expensive, exclusive regulations or expensive, complicated testing requirements riddled with Catch-22s that the working groups don't recognize.  Additional requirements may best be deployed only in areas with such extreme public interest or public safety awareness that voluntary compliance is already over 80% by popular demand.  Automatic expiration of added rules, unless a vote confirms their importance, is another good tool to reduce the lasting harm from experimental legislation. 

A Note to Legal Beagle Readers:
Regulations based on idealism rather than common law often have the unintended effect of suppressing good operators' better judgement, and allowing bad operators to proceed unchecked.
For example:
- Bans and Grandfather Clauses: It is a basic principle of law in the USA and England that you don't make retro-active laws- you can't make something previously legal, illegal, without due process.  This leads to the "grandfather clause," where existing structures that were legal when built retain their legal status as an exemption to any new rules.  If this clause is not provided, the injured owners often demand compensation for the cost of compliance. 
- A ban on new solid-fuel heaters with grandfathered exemptions (as in Missoula's air-stagnation zone) may cause expert operators to retain a poor-performing stove or fireplace because there is no option to upgrade; only to keep or remove their beloved emergency heater. 
- Reno, NV's regulation of one chimney per property, or per acre, may influence land owners already susceptible to over-use of an existing space-heater.  The one-chimney rule is a dis-incentive to certain kinds of conservative upgrades (such as installing and testing a pellet stove or masonry heater before removing the existing wood stove), and may encourage unsafe re-use of an existing chimney instead of installing a new one that matches their new heater's specs more exactly.
- Unbuildable Codes:
Well-meaning committees of building professionals, when consulted about a technical question outside their personal, physical, building experience, often add a requirement or a fudge factor "just in case."  
- Jim Buckley at Rumford.com has a great article about unbuildable, or ill-conceived, masonry chimney codes that are written off of "similar" requirements for a fireplace, hearth, etc.  He points out that the difference between supporting 8" of masonry off a 4" brick chimney wall, and 12" of masonry "just in case," is significant in terms of both structural integrity and earthquake safety. The 8" standard is visibly effective in very old buildings, and the 12" fudge factor is well-intentioned idiocy.
- In the case of our Portland rocket mass heater ATAC permit guidelines, a clause was added at the last minute to require outside air, probably due to concerns about how this thing could work with a non-standard chimney.  However, the use of both standard and non-standard chimneys had been extensively tested, and the outside air intake, at that time, had not. 

Piling on extra requirements without consideration for real-world experience is exactly the type of pompous lawmaking that had Jesus cursing the Pharisees.  It is not new, and it is not helpful. 

2) Home Inspection for Solid Fueled Heating Safety: DRAFT

When a residence is flagged as potentially dangerous, the next step would be to request an inspection by a person trained in heater and chimney safety signs (ideally a chimney sweep, as is the rule in parts of Scandinavia). 
- A 40-minute to 90-minute on-site inspection could cover the heater, chimney, clearances, fuel storage and quality, and personalized education about safe operation and maintenance.  The experienced inspector would look for signs of unsafe chimneys, over-firing, creosote buildup, past chimney fires, too-close clearances, and unsafe operation (such as smoldering green wood, using an occasional heater for full-time overnight heat,  or after-market dampers not recommended for use with a given stove).  Any problems would be flagged for a 40-day follow-up inspection.
- Clearance Field Check: The Crayon Test

If the heater appears to have scanty clearances, use a calibrated 165 F wax crayon to scrawl the relevant information on the combustible surface at its closest point.  For example, a stovepipe too close to a wood-paneled wall might have "<18 inches" written on the wall behind the stovepipe.  
Take a photo of the inspection mark for later comparison.
If they see the crayon mark melting, they should stop using the heater until they can fix the clearance or install a good heat shield.  Many owners will voluntarily put up a heat shield just to hide this ugly inspection mark; inform them the mark must remain accessible for the follow-up inspection, but it may be possible to check it by remote camera or by unbolting part of an add-on heat shield or chimney guard. )
- Smoke Check Verification: If no obvious problems are detected, the inspector may ask the operator to start up their heater, to see that not more than 20 minutes of visible smoke occur.  During these 20 minutes, the inspector and owner can discuss safe practices, tour other outdoor elements such as fuel storage and fire-wise landscaping, or swap ideas about how to achieve overnight warmth without unsafe smoldering.  Inspectors may suggest for an easier/more efficient heater if the resident is interested, but inspectors caught pushing product sales or threatening a bad inspection report may be permanently disqualified from local inspection lists. 
- Any operator who can safely and cleanly operate their chosen solid-fuel heater, demonstrating both day and night practices without more than 20 minutes of visible smoke, should be passed on the first inspection. 

Inspection Checklist: DRAFT
- Heater/stove/fireplace appears to be in safe, operable condition, properly installed, etc.
- Chimney appears to be in safe, operable condition, properly installed, and with no signs of hazardous creosote or leaks
- Clearances to combustibles, both fixed and portable, appear adequate and safe.
- Operator practices appear adequate for safety including fuel storage, fire tending, and household habits
- Operator is able to to meet the <20 minute smoke standard, including overnight heating practices; or there is special cause for exemption.

If the initial inspection is a no-pass, provide detailed notes and/or photo evidence of the pieces needed, and schedule a follow-up inspection for not more than 40 days in future.

Inspector Qualifications: DRAFT
Any licensed/registered chimney sweep in practice for 5 years or more, and any trained fire scene investigator with a few season's experience, would likely be able to do this type of inspection without further training.  Many local fire fighters, stove installers who service their own work, and ordinary citizens would be able to inspect, but might need to be endorsed by one of the former experts in case of any doubt regarding their skills or conflict of interest. 

The goal is to have a generous pool of qualified inspectors who can visit any home on reasonable notice, without needing to charge unaffordable rates for the county or poorest members of the public they serve.

Jurisdictions with adequate resources may maintain a non-exclusive list of qualified inspectors.
 Any list of qualified inspectors must be impartial, based on national fire-safety standards, with multiple avenues of endorsement to discourage local, petty anti-competitive clubbing.  Inspectors cannot be appropriately vetted by a non-qualified person such as a county clerk, elected official, or legal advisor, except to administer a background check or verify accusations of malpractice. 
Any inspector may be removed from the list for deceptive, fraudulent, incompetent, or conflict-of-interest practices, such as only passing her direct customers and failing others, or a pattern of preventable fires in homes that passed on his last inspection.

All inspectors should learn from experience. Part of the commitment of a registered/qualified inspectors might be to visit and investigate any fire scene that happens in a location they previously inspected and passed. If preventable fires happen under a particular inspector so often that visiting each burnt home becomes onerous, consider self-disqualification.

Jurisdictions may wish to create an inspection certificate, and perhaps include a waiver/exemption so those who pass on their first attempt will be excused from further inspections.  For a sample certificate text, see below.

3) 40-Day Follow-up Inspection, As Needed: DRAFT

Procedure: Same as initial inspection, with special attention to problem areas.
- Re-check the entire list.  Special attention to previous inspection's fail points. 
Even in areas that passed, re-check for signs of creosote/chimney problems that may be building up since last inspection.   In case of scanty clearances, check the wax mark to see if it has melted indicating unsafe temperatures. 
- If the chimney and stove appear in good condition, the operator can pass the <20-minute smoke standard, and the wax mark is unaffected, the home passes inspection.  Provide a signed note or certificate of successful inspection, and give them the go-ahead to re-paint or re-paper their inspected wall(s).

Inspector qualifications: Same as above. 
The operator may request the same or a different inspector, if available.  Every effort should be made to provide a choice, and to facilitate good passdown from the initial inspector to the follow-up inspector to guarantee safety and fairness.

Why 40 days? 
Safety Thresholds: In our region, wood heaters start up around September/October, and we routinely see chimney fires and barn fires uptick in November/December on through the winter.  "I just cleaned my chimney," mid-winter, has entered my vocabulary as a danger sign.  Waiting two months might be too long for extremely unsafe operators; 30 days might not be enough to detect evidence of the difference in their new practices.
Human Thresholds: There is some evidence that 40 days/6 weeks is about the time it takes for human beings to transition from old habits to new ones, such as a new exercise or diet regime. The first few weeks after a change, most people experience difficulty, awkwardness, upset or confusion; after 5 or 6 weeks practicing a new habit, things start to settle back down into a workable state.  40 days is the experiential threshold for "a new normal."  In biblical context, it often represents a long time period, such as a transformative flood or fast, after which there is no going back to the way it was before.

4) No-Pass / Repeat Offenders

Operators and households that fail multiple inspections may be a danger to themselves and their communities.  Families unable to heat their homes in winter are also in immediate danger.  Balancing these risks to compassionately serve the needs of the whole community is the highest calling of local leaders in public safety, health and social services, and good governance.

Prevention and Support: Communities may need creative, ongoing efforts to delineate fair and humane rules concerning exemptions, re-inspection, waivers, insurance eligibility, fire district fines/taxes, social services for elders/disabled at risk, etc. 
The goal is not to over-burden or punish the poor, but to help owners to remain in their own homes to the greatest extent possible while mitigating preventable dangers to themselves and their neighbors.  Repeat offenders within city limits, in burn-ban or wildfire-prone areas, or on rental properties might face more severe limitations than owner-operators living in rural areas with low seasonal fire risk. 

Prosecution: Repeat offenders who have already caused multiple fires may need to be handled under the criminal justice system, as even involuntary 'arson' or 'attempted manslaughter' is a serious offence against community safety.  Many agencies and jurisdictions have existing policies covering the appropriate circumstances to fine, bill, or press charges against responsible offenders for the cost of fire control efforts.

Voluntary Compliance vs. Enforcement:

Consider ways to promote voluntary compliance and preventive inspection where possible.  The embarrassment, expense, and inconvenience of a formal inspection may in itself cause resistance, or become a weapon in "neighbor feuds" and public-nuisance harassment.  
: fire districts or schools might host a community bonfire event or other public education outreach events to help the public learn safe practices.  Inspectors or insurers could offer coupons for voluntary/preliminary inspection, discounts, rebates, etc.  Fire departments could use smoke-checks as a way to familiarize new recruits with their district between calls.  Elegant congratulatory certificates allow inspectors to reward excellent owner/operators with special recognition:

Certificate of Residential Safety Inspection for Solid-Fueled Heaters, Stoves, and Fireplaces:
The owner/operator _____________________________
at this address: _________________________________
in the county of ____________________
has passed inspection on this date ____/___/_____
for the following criteria:
- chimney(s) in good operating condition
- stove/fireplace(s) in good operating condition
- acceptable clearances to combustibles
- acceptable operator skills and practices for clean and safe operation (low- to no-smoke)

Waiver: From this date, the owner/operator at this location may be excused from further inspections for
__1 year,
__3 years,
__5 years,
__outstanding excellence: the operator ________________ is recommended for recruitment as a qualified inspector.  To use this waiver, please record the operator's contact details: __________email __________phone

Inspected by _______________________, signed and dated ________________________,  __/__/__
Inspector's home agency or qualifications:__________________________________
Inspector registration ID (if applicable): ___________________________________

Call for Comments:

This is a DRAFT proposal, version 1 dated March 6, 2017.
Heating experts, public safety organizations, and former EPA inspectors with time to burn - please comment

Email your comments, or your own edited/proposed version of similar rules to: [email protected]
Please include the phrase "Smoke Check" in the topic or body of the message, if possible.

The author, Erica Wisner, is a 20-year public science educator, freelance R&D innovator in sustainable heating and cooling, author of several books including the Rocket Mass Heater Builders' Guide, and a volunteer fire fighter in Okanogan County, Washington, USA.