Air Quality – Open Burning
The CBJ Air Quality Monitoring Program: October 1 – April 30
- CBJ staff monitor air quality data hourly to detect fine particulates from woodsmoke in the air.
- If data shows high concentrations of these fine particulates, the CBJ will declare an air emergency, which prevents woodstoves from being used until the emergency is cancelled.
- The CBJ works in partnership with the Alaska DEC and NOAA to ensure the Valley’s air remains clean and healthy.
During an air emergency, all woodstove burning is prohibited until further notice as outlined in CBJ’s ordinance 2008-28 regarding solid fuel-fired burning devices. Pellet Stoves are exempt from the wood stove regulations and can burn at any time. Masonry heaters that fit the definition given by the Masonry Heater Association of North America are also exempt from the wood stove regulations.
An air emergency will be announced through press releases, advertising, and by utilizing the11 neon yellow air emergency signs in the Valley when air particulate levels reach, or are currently at, an unhealthy level and weather conditions will not clear the air. CBJ staff will always update the Online Air Quality Advisory and the Woodsmoke Hotline if an air emergency is or is not in effect.
The maps below detail all homes located within the Woodsmoke Hazard Area:
Below are hourly air samples of fine particulates (pm 2.5) that were present in the Valley’s air during the 2015-16 air quality monitoring season. These samples were taken at the Department of Environmental Conservation’s Floyd Dryden Station, and demonstrate what is usually invisible to the eye: fine particulates from wood smoke.
Fine particulates from wood smoke are the ones that can lodge themselves deep into the lungs and significantly impact children, elders, and those with breathing difficulties. The darker the circles, the dirtier the air. If the air is clean, the hourly samples will run clear (almost invisible to the eye) when looking at the Beta Attenuation Monitor (BAM) tape. CBJ Lands and Resources staff monitors the data produced from these hourly air samples, and will call an air emergency if numerous readings in a row show that the air quality could threaten human health.
What Causes Unhealthy Air in the Mendenhall Valley?
An air inversion. On windless, winter days, normal atmospheric conditions can become
inverted: a layer of warm air prevents cold air from escaping and acts like a lid, trapping woodsmoke
and other pollutants in our air. The natural “bowl” shape of the Valley intensifies this condition.
- Printable Flyer – This flyer explains how air inversions occur and how to help avoid unhealthy air.
Notice the thick blanket of smoke shown above? That “blanket” or air inversion will continue to trap all the fine particulates from woodsmoke and open burning until wind or rain clean out the air. When it looks like an air inversion is forming, the City’s goal is to temporarily stop the use of Valley woodstoves and prevent the high concentration of fine particulates underneath that smoky blanket.
Monitoring the Mendenhall Valley’s air quality would not be possible without the collaboration and support of the Department of Environmental Conservation, Division of Air Quality team and the National Oceanic and Atmospheric Administration, Juneau Forecast Office who collect and interpret the data. Additional partnerships are with the Juneau Police Department, who enforce the air emergencies and burn bans, and the CBJ Clerks Office, which has posted when air emergencies are in effect or cancelled on the CBJ Facebook.
On October 5, 2016, CBJ Lands and Resources staff along with Alaska Department of Environmental Conservation went on Juneau Afternoon to discuss the 2016-17 Air Quality Monitoring Program. If you missed the conversation, click the below KTOO link and start listening in at minute 46.
How Can I Help? (Printable Flyer)
- BEFORE LIGHTING YOUR WOODSTOVE, call the CBJ Woodsmoke Hotline at 586-5333 to see if an air emergency
is in effect, or check the CBJ Lands and Resources webpage at www.juneau.org/lands/woodsmoke.php.
- LOOK FOR DAYS THAT ARE SUNNY, windless and cold: these are signs for a potential air inversion.
- KEEP AN EYE OUT FOR THE NEON-YELLOW, BURN-BAN SIGNS that will be flipped open if an air emergency
is in place.
- LISTEN TO THE RADIO for air-emergency PSAs.
- BURN ONLY UNTREATED WOOD, paper and cardboard in a woodstove. Don’t burn garbage, plastics,
treated lumber or anything unnatural.
- BURN DRY, WELL-SEASONED WOOD. This reduces particulate and carbon-monoxide transmission to
- BONUS! DRY WOOD PRODUCES MORE HEAT, which means you use less wood, which means you save
money and work.
- DON’T OVERLOAD YOUR STOVE. Keep fires small and hot.
- KEEP YOUR STOVE’S INTAKE/DAMPER OPEN ENOUGH TO MAINTAIN A HOT, CLEAN FIRE. Smoldering fires can
cause six times more emissions than a hot, clean fire. Did we say “hot, clean fire” enough?
- GO OUTSIDE AND CHECK YOUR CHIMNEY FOR HEAVY SMOKE. If it’s heavy, you’re likely burning damp
wood or something is making your stove burn inefficiently.
- WHICH BRINGS US TO THIS POINT: Have your woodstove inspected to make sure it’s functioning
properly, safely and efficiently. Like dry wood, an efficient stove means you’ll burn less wood, which
saves you money and work.
- CHECK FOR CREOSOTE BUILD-UP AND KEEP CHIMNEYS CLEAN. It’s probably best to have a professional
chimney sweep (which is a real job title) come out to do the inspection of your woodstove and
chimney. A properly functioning woodstove is not only better for your home heating and your wallet,
it’s also safer for your family.