Power Saws
My neighbor asked to borrow my chainsaw. My first thought regarding someone that doesn’t own a chainsaw is that they don’t know how to safely use it. I replied “No, but I’ll cut whatever you need and even show you how to use one” full well knowing I have extensive experience with chainsaws. The same is true in the fire service in that it is incumbent on instructors and/or officers to train those that don’t know how to use power saws on the fireground.
Because of the inherent and significant safety concerns while using power saws instructors must place an emphasis on safety right from the initial training program. Once the concept of safety has been established then instructors can advance training with saws by discussing typical uses include but are not limited to any truck work such as forcible entry, ventilation and possibly clearing downed limbs. Saws are also used in extrication and lastly FAST (firefighter assist and search team).
With the assumption that safety has been established this article will focus on characteristics of specific saws that can and should be taught. As with uses the list of saws presented here is not limited as there isn’t a way to cover each type in a single article. Before delving into specifics there are some commonalities that span across all saws.
For example:
1) On the fireground always start any saw on the ground or other level area BEFORE proceeding to a roof or down an embankment to use. The reason for this is a firefighter doesn’t want to lose their balance while trying to get a saw initially started (assuming secondarily the saw starts up smooth and firefighters can position themselves accordingly on an unbalanced roof) and second it’s a lot easier to troubleshoot a startup issue on the ground and also there is likely a tool on the apparatus that can solve any startup problems.
2) Always start up any saw during truck checks to ensure that it starts correctly and taken out of service if necessary.
3) Check fuel level and/or battery life both in the saw and any fuel reservoirs to make sure you have enough power for a fireground task.
4) Check sharpness on any cutting edges. This can be done simply by keeping a logbook of uses.
5) Even if your department has a specific person to repair saws every firefighter should know how to take apart and clean each saw so in the event it is necessary to do so on the fireground.
Chainsaw:
Uses:
Cutting ventilation holes in roofs and forcible entry to clearing branches of a downed limbs.
Features:
Most chainsaws have a chain brake. It looks like an additional handle but when pushed forward stops the chain preventing it from moving even when the throttle is pressed. This is a safety feature that firefighters must get used to activating because in many instances there are other firefighters within close proximity to a moving chain.
The handles on chainsaws usually run on top and on the one side. This is because there are obviously times when the bar/chain has to be turned to the side to complete a cut.
Chainsaws are inherently for right-handed people but can be used left-handed and as an instructor I would encourage during drills to use a chainsaw from both sides.
Electric Chainsaw:
Uses: Similar to a chainsaw
Features:
Also, similar a gas-powered chainsaw with one HUGE exception. Electric chainsaws will likely not have the torque and power. The end result is that while an electric chainsaw can be used to make a door out of a window for a FAST extrication it may not be the best tool if a gas-powered chainsaw is available because what materials are in a wall is a mystery.
Also, battery powered chainsaws are limited to their battery life so make certain to have spare batteries for applications that require a long period of time.
One advantage to an electric chainsaw is they tend to be more balanced than other power saws and in many cases the chain stops automatically when the throttle is released making a chain brake unnecessary.
Cutter’s Edge:
Uses: Almost exclusively cutting ventilation holes in roofs.
Features:
A cutter’s edge is essentially a chainsaw but with one outstanding feature. There is a depth guard to set that allows the saw to only cut to a certain distance through a roof thereby preventing the cutting of any studs that would weaken the footing underneath.
K12 Saw:
Uses: Extrication, ventilation, forcible entry
Features:
For the most part a K12 saw will cut through most any material but only in accordance with the blade that is on it is designed to cut.
Other important factors for a K12 are that because it revs at a very high RPM it is inherently unbalanced. Combined with its weight can be difficult to handle as a result.
The most important feature of this saw is that is has no chain brake. Again because of the high RPM will not stop and remains a safety concern for at least a minute while it slows and stops. From that perspective it might be better to bury the blade to stop it right away.
As mentioned, the four saws presented here are the most common but by no means are a finite list as there are quite a few types of power saws available and used in the fire service. For example, a rescue company might also have a whizzer saw which is a small handheld saw. It has a small blade and revs high because it is designed to cut tempered auto glass whereas a reciprocating saw can also be utilized in several applications. Regardless of the saw type it is imperative to practice, practice, practice. Using a power saw for the first time on the fireground is not the time to learn the ins and outs of any particular one.