Navigating Your Way on a Steep Roof During Ventilation Operations with the ‘Mattson’

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Blog by Ed Hadfield
Doing the “Mattson” is a term for establishing a foot purchase on a roof while working off a ladder and performing vertical ventilation operations. This concept was created by Seattle Fire Department’s Brian Mattson, who began utilizing it during his assignment to the Ballard Area, which is known for its large Victorian-type homes.
Establishing a strong foot-hold and sound foot-point is critical to a successful operation. Generally, working off a roof ladder is a low-frequency, high-risk event. In the past, personnel were told to utilize a roof ladder to distribute their weight and limit their exposure of falling through the roof. But this is a poor strategy. Remember, if the roof is not capable of handling the weight of two firefighters – two personnel are the typical residential roof assignment – then ventilation operations should be adjusted to another area, or transitioned to another type of ventilation operations.
All personnel should be completely aware that any area considered unsafe for completing vertical ventilation operations should not be allowed to operate underneath the roof assembly. Bottom line: If it is unsafe to assign personnel to the roof, it is equally unsafe to put people underneath. After all, roofs fall down. All personnel assigned to vertical ventilation operations should be in full PPE and have radio communications with interior crew and IC.
Please take a look at the images below for a step-by-step overview of the process.

 

 

The first step in the process is to complete a “Tool Swap.” The initial sounder, or person in front, should pass the rubbish hook to the back-up person by placing the tool to the outside of the operations and grasping the chainsaw in a pass motion on the inside of the operations. Or simply put, “tool to the outside – saws to the inside.” Saws are always passed with the chain break in the on position and the body of the saw first.

 

 

 

 

The first step in this process is to have the back-up person place the rubbish hook/roof hook into the deck. The back-up person will place the near tine into the deck with a downward strike. Notice that only one tine is placed into the deck.

 

 

 

The initial cut will be toward the fire to establish the identification of the primary outside rafter. Once the outside rafter is identified, the saw is turned around and the head cut is established by reversing the direction, rolling the center rafter and stopping at the next rafter or before you cut into your roof ladder. Keep this key point in mind, chiefs don’t like when you cut into the ladder. The next step in the sequence is to establish the outside cut. Be sure to intersect your head cut and outside cut with enough completion to completely cut through the roof decking. If your roof decking is 2 inches in thickness, your intersection should be 4 inches.

 

 

 

Your next step is to make the bottom cut. Intersect the outside cut with the bottom cut, cut back toward the safety of your ladder, rolling the center rafter, and stopping at the inside rafter.

 

 

 

 

 

 

Then, the final step is to complete the ventilation opening. Step back completely onto the ladder and intersect the head cut, cutting down the inside of the inside rafter. Please note that when making cuts that are parallel to rafters, give up approximately 3 to 4 inches of area so you don’t rub or cut into the rafter as the operation is being accomplished. The back-up person has removed the rubbish hook from the deck and readies himself to swap tools to accomplish the operations.

 

 

 

 

Again, the “tool swap” occurs with the saws to the inside, and tool to the outside. This limits the need to swap positions.

 

 

 

 

 

 

 

 

 

Once the swap has occurred, the saw person utilizes the hook to clear the ceilings and vent the structure from the hazards of heat, smoke and other hazards. The elimination of the rapidly developing BTU’s within the structure will greatly reduce the potential of a hostile event (flashover, backdraft, smoke explosion, etc.). It’s important to keep your hand on the D-handle portion of the hook while clearing the ceilings. This will limit the chances of the hook sliding through your hands and into the structure. If you find that the hook tines are catching or other entanglement hazards, turn the hook over, grasp the straight edge of the hooks, and utilize the D-handle as the clearing mechanism.

 

 

If the initial hole is not sufficient to clearly ventilate the structure and additional ventilation needs to be accomplished, simply perform the “Tool Swap” again and continue to expand the original ventilation opening in a horizontal fashion. Since a bottom cut is already established there is no need to reestablish the identification or head cut. Continue with the outside (fire side) cut in a downward fashion.

 

 

 

 

Intersect the outside cut with the new bottom cut and roll the center rafter back toward the safety of the ladder. Once back to the outside rafter, reach up intersect the bottom of the existing opening and move downward with the completion of the inside cut and the intersection of the new bottom cut. Again, complete a “tool swap” and clear the ceiling space. This has completed the entire task and radio communication with interior crews or the IC should be made to determine if the ventilation operations have been successful in relieving the conditions that the interior crews have experienced.

The bottom line is that no operation is effective unless we actively train and become proficient at the operation. Utilize this as a foundational format to establish your operations within your own organizations.

About the Author

Ed Hadfield has more than 26 years of fire service experience after rising through the ranks from firefighter to division chief. He is a frequent speaker on leadership, sharing his experiences within the fire service and also with corporate and civic leaders throughout the United States. For more on Hadfield, please check online at www.firetowntrainingspecialist.com.

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