Mulch is a combustible material that can be easily ignited by improperly discarded smoking materials. Hundreds of small and large fires are started this way every year. The risk is that what starts as a small outdoor mulch fire can quickly spread to buildings. A mulch fire can be well underway before someone notices or is alerted by smoke alarms or sprinkler systems activating.

New Regulation on Mulch Safety

The new regulation (527 CMR 17), took effect September 2012 and prohibits the new application of mulch within 18″ around combustible exteriors of buildings, such as wood or vinyl but not brick or concrete. Residential buildings with six units or less are exempt from this regulation, but all homeowners may also wish to adopt these safety practices. The regulation applies to all other buildings including commercial properties.

Tips for Property Managers, Building Owners, & Landscapers

• Provide a minimum of an 18 inch clearance between landscape mulch beds and combustible building materials, such as wood, vinyl siding, and decks.
• Use non-combustible mulch such as rock or pea stone around gas meters and combustible portions of the structure.
• Provide proper receptacles for smoking materials at all entrances to public buildings and in designated smoking areas and remember to regularly empty smoke receptacles.
• Grounds and maintenance crews should be aware when conditions are favorable for mulch fires and increase surveillance of mulch beds.
• Keep mulch beds moist when possible.

Million Dollar Mulch Fire

• The most notable event occurred at a Peabody apartment complex in May 2008. A cigarette-lit mulch fire caused a $6.7 million loss, displaced 750 people temporarily and 36 permanently.
• In April 2012, improperly discarded smoking materials ignited mulch outside an assisted living center in Braintree. The fire forced the early morning evacuation of many older adults, some of whom suffered smoke inhalation injuries.

Report Mulch Fires

• If you see anything smoking in a landscape bed, put it out if you can and report it. If the burning material is not thoroughly wet or removed it might re-ignite.
• Report any smoke or fire via 9-1-1.

Be a Responsible Smoker: Put it Out. All the Way. Every Time!

• If you smoke, remember to properly dispose of all smoking materials.
• Always use appropriate receptacles for disposing of smoking materials and matches.
• Don’t discard cigarettes into mulch or potted plants.
• At home, use ashtrays that won’t burn or catch fire and that are deep. Wet them down before throwing out.
• As more people smoke outdoors rather than inside, many building fires started by smoking begin on decks, porches, and exterior stairways.
• Be smart in your choice of containers for butts. Consider using metal cans with sand for outside disposal.
• Because of the risk of starting a fire, do not throw lit smoking materials out of the car window, it is illegal to do so and punishable by a fine of $100 and/or thirty days imprisonment (MGL C148 S34).

How Mulch Fires Start

• In many mulch fires, the smoldering mulch tunnels under the surface and then breaks out into open flame.
• Mulch that is piled too deeply, more than a few inches, can build up heat and spontaneously catch fire.
• Mulch fires start more readily when the weather is hot and it has been dry for an extended time.
• Factors such as below-average rainfall, dry conditions, warm temperatures, and high winds increase the risk of mulch fires.

Source: FireFACTORS – Office of the State Fire Marshal, Massachusetts Dept of Fire Services