chimney fire training by b0VT2qH

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									  Chimney Fires
 Chimney Fires

 Construction, Challenges
Fire Control Best Practices
                Objectives
• Review different types of chimney
  construction
• Identifying lines vs. unlined flues
• Understand fire spread characteristics of
  most common chimney types
• Effective fire control practices
         Chimney Construction
• The chimney method
  of smoke removal has
  been around for
  centuries
• Early man discovered
  the benefits of vertical
  draft methods in
  removing smoke from
  caves, huts, etc.
Chimney Construction (cont.)
              • Various means to
                construct vertical
                drafts (chimneys)
                used:
                 –   Stone
                 –   Mud/sticks
                 –   Hollow logs
                 –   Bricks
                 –   Metal (modern)
          Attachment Methods
•   Interlock wall stones with chimney stone
•   Free-standing
•   Wall logs interlocked in stone or brick
•   Metal ties to wall framing (20th century)
•   Metal bracing within wood framework
    (modern zero-clearance chimney piping)
                  Lined Flue
• Inside of chimney
  construction contains
  flue “pipe” or “lining”
  that minimizes
  openings, joints, or
  crevices along vertical
  path of heat, smoke,
  embers
Metal Chimney Liner
Tile Chimney Liner
       Liner Characteristics…
• Each type of liner has it’s benefits and
  drawbacks…
  – Metal is expensive, but crack resistant and often
    installed in one piece top-to-bottom.
  – Most common sizes are 6- and 8- inch
  – Easy connection to wood/coal stoves
  – Can be routed through some twists and turns
  – Can retrofit old, unlined flues
    Liner Characteristics (cont.)
• Tile, or terra cotta, offer wider passages
  than metal and are less expensive than metal
• Not used in retrofits or relining of existing
  flues
• Susceptible to temperature extremes and
  settling of foundations, causing cracking
• May consist of several joints
 Zero-Clearance or Prefabricated
      Metal Chimney Flues
• Developed nearly 25
  years ago to service
  the growing
  alternative heating
  market
• Consist of multiple
  layers of stainless steel
  separated by fire-
  retardant insulation
             Unlined Flues
• Found in many homes
  built prior to 1930
• May be of stone or
  brick construction
Unlined Flues (cont.)
Fire Spread Characteristics
       Tile/Terra Cotta Liners
• Cracks appearing over time and temperature
  extremes provide openings for hot
  ash/embers to exit the flue and contact
  adjacent combustible framing members
• May also provide path into void spaces,
  carrying sparks into area containing
  combustibles (attic, behind knee wall)
   Terra Cotta/Tile Liner (cont.)
• Subject to degradation
  from rain, ice, snow
• Mechanical damage
  from improper
  cleaning, previous
  fires
• Damage introduced
  from exterior forces
  (wind, trees)
Metal Chimney Liners
          • May warp from
            extremes in
            temperature (burning
            stove too hot)
          • Improper attachment
            of flue sections
          Metal Flues (cont.)
• Joints may be open, allowing sparks and
  embers to escape into void and combustible
  spaces adjacent to chimney, permitting fire
  spread and slow detection of same.
• Stainless steel tubular liners are used in
  older unlined retrofitting, often resulting in
  turns and twists permitting build up of
  creosote and animal nests.
            Creosote Buildup
• Creosote is a
  byproduct of
  INCOMPLETE
  combustion.
• Adheres to tile,
  unlined, flexible
  metal, and joints in
  flue liners
           Creosote (cont.)
• Relatively cool temperatures in upper
  portion of flue condense products of
  combustion into potential “time bombs” on
  liners.
• Can be minimized by burning proper fuels
  (seasoned wood) at proper temperature
  recommended by stove/fireplace
  manufacturer
Animal Nest in Chimney Flue
    Retrofitting Unlined Flues
• It is common to find older, unlined
  chimneys outfitted with new style flexible,
  stainless steel tubular liners
• Often connect to wood stove or insert
• May be placed in unlined flue surrounded
  by fire-resistant material such as a
  vermiculite/gypsum mix
 Prefabricated Metal Chimneys
• Have Class “A” fire rating and may be used
  inside of wooden box framing according to
  building codes and Underwriter’s
  Laboratories test results
• Lock together in a twisting motion
• Are NOT fire PROOF!!!
Identifying Fire Presence and
       Control Options
         Caller Complaints
• Hear persistent “roaring” sound from upper
  flue area
• Smoke from chimney when no active fire in
  fireplace/ stove
• Haze/smoke odor in upper floors of house
  and/or attic
• Walls adjacent to chimney hot to touch
        Fire Control Tactics
• Thermal Imager A MUST!!!!
• Get personnel ABOVE and BELOW
  fireplace/stove-check walls, floor space
  adjacent to flue--attic
• Check flue clean out (if present)
• Roof crew to check openings at top
            Tactics (cont.)
• Remove active fire from firebox
• Closely monitor flue for active flames
• Consider use of dry chemical extinguisher
  or “chimney bombs” (dry chem in plastic
  baggies dropped from top of chimney)
• Pressurized water extinguisher and/or
  preconnect should be LAST RESORT
• Once fire controlled, occupant must be
  directed to have licensed chimney sweep
  clean and inspect chimney PRIOR to ANY
  additional usage.
• Officer should document this on NFIRS
  report.
        Points to Consider…
• Successful control of chimney fires requires
  time and patience
• Continual monitoring of all adjacent
  combustible areas required during
  operations
• Older, unlined flues often contain structural
  framing members tying chimney to house
          Other Important
          Considerations…
• EARLY laddering of roof
• Use of chimney chains to clear flaming
  creosote (if available on scene)
• Aggressive investigation of adjacent void
  spaces
• Identification of lined vs. unlined flue
                Summary
• Firefighters should be familiar with the
  various chimney types
• Understand particular hazards of each
  type of flue
• Recognize signs of active fire situations in
  flue and execute proper control methods
           Summary (cont.)
• Make every attempt to control fire while
  minimizing damage to chimney/flue
  structure
• Ensure safe operations when working in
  poor lighting and on wet/icy or steep roof
  pitches
• Have a safe, happy, injury- and fire-safe
  holiday season!!!!!

								
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