Sunday, May 23, 2010

Ladder Dogs

Ladder Dogs

By Emmett "Pat" Nichols, Boston Fire Department Tower Ladder 10 (photos by author)

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Ladder Dogs, also known as dog chains, are used in Boston and surrounding communities as an additional margin of safety when placing ladders at precarious angles and/or sloping terrain. There are two chains which are placed at the tip of the ladder and crossed when the ladder is placed in a rescue position (See photo 1). One chain is used when the ladder is placed at the left side of the window when the ladder is placed for firefighting; utilizing the window frame to secure the ladder from moving to the left (See photo 2). One dog chain would also be utilized when the ladder is placed adjacent to a metal fire escape to secure it from sliding across the building. In that case, there is a hook on the chain to allow it to be looped around the fire escape and clipped back on itself.

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The dog chain consists of: a chain approximately 18 to 24 inches; a metal 2 or 3 inch loop at one end (See photo 3);  and a sturdy hook/spike at the other which would be driven into the wood window sill or roof line.  To apply the dog chains, you bring the ring end of the chain through the top rung between the beams, bringing it under the beam;  then,  feed the spike end through so it will cinch down when the spike is brought across and driven into the wood sill or roof line.

This procedure should be utilized when there is a risk of ladder movement or hose line operation over the ground ladder. It should not sacrifice proper technique or placement, but when added safety is required, then the dog chains will offer the desired safety.

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1 comment:

  1. Nice explanation and illustration, Pat. Did you take those pics at "the college of fire knowledge". aka the MFA?