Ventilation in the Fire Service
By Member Earnest Theetge
March 31, 2020

All too often I hear people ask “Now why did they have to go and cut a hole in the roof.” This is a subject that is often tricky in the fire service and must be completed in a group effort, with communications from the incident command, interior firefighters, and roof operations. So what does ventilation do on the inside of the structure? First of all our main goal in the fire service is life over property. If we can coordinate ventilation the heat and dangerous gases will exit the structure and make our job easier on the interior while searching for victims and even the fire.

There are different types of ventilation we perform in the fire service during the fire and also during overhaul. Overhaul is when all firefighters on the inside of a structure are looking for any smoldering embers that could flare back up resulting in another fire. Ventilation is and can be a very dangerous job performance that requires competent firefighters to climb on a roof of a structure that is on fire. The skills required for this job may seem easy, however one wrong cut through a rafter could cause the firefighter to fall through the already weakened roof into the fire ultimately losing his/her life. The tools used in this fire ground operation also have a lot of moving parts. We ultimately use a chain saw or a circular saw( K12) to perform this task, but even machines can fail and what we will always fall back on are our skills handed down to us through generations of firefighters.

The trusty pick head axe (fireman’s axe) is always our tool that will never fail us. The firefighters need to physically fit in this position so we can revert back to the axe to cut a hole in a roof. The next method is positive pressure ventilation (PPV). This is where we set up a fan at the front door of the structure covering approximately 70% of the opening or doorway. The PPV can be a great tool, but if performed wrong can cause the structure to flashover creating a loss of life and property on the interior. Hydraulic ventilation is when we use a fog pattern hose stream to pull smoke from the interior out of a window or door way. With the types of ventilation performed in the fire service it is always imperative that we use our training and communication to assist in bringing the fire scene to a fast and timely end.