ESCONDIDO FIRE DEPT TRAINING MANUAL Section Engine Module Page 1 of 5 Wildland Chain Saw Operations Revised

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1 Engine Module Page 1 of 5 CHAINSAW OPERATIONS A chainsaw is a valuable tool used to cut timber and large diameter brush. However, when used improperly, it can cause serious injury to the operator and assistant (swamper). A key item in chainsaw safety is proper judgment when combined with safety equipment and training. This section is not designed to provide the entire training necessary to make a competent operator; instead it will provide valuable information prior to beginning a chainsaw training program. Safety equipment required for chainsaw operators: Hardhat. Ear muffs or foam earplugs. Eye protection including wrap-around safety glasses. Long sleeve shirt with safety gloves. Chaps, a thick woven cotton/synthetic blend material designed to protect the legs of the operator. Before Operation Procedures All chainsaws should be stored in a ready to operate condition. The fuel tanks should be topped off, oil reservoirs full, and chain tension adjusted correctly. Leaks from the fuel tank and oil reservoir caps can be prevented by not over-tightening the lids. Once the seals have been damaged they need to be replaced. In addition to the saws being stored in a ready condition, extra fuel mixed according to the departments and manufacturers recommendation, bar oil, a spare spark plug in case of fouling, and chain adjustment tools must be readily available. Starting the Saw Normal starting procedures for a cold saw vary by manufacturer but general guidelines apply to two-stroke motors. Refer to both manufacture and department procedures for power equipment prior to operating saws. 1. Apply the choke and set the throttle. 2. Start the saw on the ground in a clear area. 3. Pull the starter rope firmly keeping hold of the handle with the left hand. 4. Rev the engine briefly to release the throttle control mechanism. 5. If the saw does not start after 2 to 3 pulls, reduce the choke. (Flooding the carburetor is the most common reason for two-cycle engines not starting.)

2 Engine Module Page 2 of 5 Starting a Saw if the Carburetor is Flooded 1. Fully Open the choke allows maximum air flow 2. Squeeze and hold the throttle fully open 3. Pull the starter cord until saw either starts or starts and stops If the saw, starts and then stops, use the steps for Starting the Saw again. Handling a Chainsaw The following techniques will allow the chainsaw user to operate the saw with increased efficiency, reduced fatigue and a higher level of safety awareness. Maintain firm footing with legs spread apart. Keep the body away from the saws cutting path. This is especially important when using a swamper to assist with removing cut materials. Do not approach the saw from the front or in line with the saws bar. Keep the weight of the saw close to the body. Allow the saw to do the work; no back-and-forth cutting motion similar to a handsaw is required. Saw Operation The safest and least tiring method of sawing is to use the backward running, or lower portion of the bar close to the Dogs (sharp spikes on saw at end of bar). When cutting large diameter material, set the dogs of the saw into the limb of the stump. Always allow the weight of the saw to do the work. Cutting with the top portion of the bar can cause kickback, which is a dangerous situation. Kickback occurs when only one or two cutters engage in the wood at a given time and the chain jams. The rapid deceleration causes a violent upward and backward motion of the saw. To prevent kickback injuries, the following guidelines must be adhered to: Hold the saw firmly with both hands. Keep thumb around the top of the handle. Example A Use a saw equipped with a chain-break or kickback guard. Watch for small twigs or vines that can snag the chain. Saw with the lower portion of the bar. Maintain adequate saw speed when starting and completing a cut.

3 Engine Module Page 3 of 5 Example A Tree Felling Felling a tree requires several cuts and requires a high degree of skill and experience. Tree Faller S-212, is a NWCG certification tract and is required to work at wildland fires. Without having a tree faller certification with regular practice/training, only standing trees less than 6 inches in diameter or 24 inches circumstance at chest height may be felled by Escondido Fire Firefighters. Numerous injuries and fatalities occur in the timber industry annually. The following section will provide a brief description of the procedures used by experienced fallers. Identify safety hazards. Determine the height of the tree and its lean, which determines the direction of fall. Plan the escape route prior to beginning the cuts. Clear any hazards including limbs and branches in the path. The escape route should be at a 45 angle to the direction of fall. Make sure the saw is full of fuel and oil before beginning the cuts. Clear the area of personnel with the exception of the swamper. Make the three cuts in the following order as identified in example B below. Wedge the tree over if the tree leans back binding the saw. Quickly remove the saw from the cut and retreat down a predetermined escape route.

4 Engine Module Page 4 of 5 Example B NOTE: Notice the two-inch difference in height between the bottom cut and back cut. Bucking and Limbing Bucking is the process of cutting up the trunk and large limbs into manageable sections prior to removal from the fire line. Clear footing must be maintained while bucking up tree limbs. Never work on the downhill side of the material being cut. Caution must be exercised when cutting limbs under tension and compression as the material can spring back at the sawyer and can bind the bar causing damage to the saw. Limbing is the removal of branches from trees along the fire line. Limbing is started along the trunk of the tree or brush. Cutting fire line in heavy timber requires limbing the interior and exterior perimeter at pre-determined distances. Poor footing and obstructed vision can lead to accidents. The saw should never be used above shoulder height. The saw operator should keep the main tree trunk between the

5 Engine Module Page 5 of 5 saw and operators body, refer to example C below. When cutting fire line, the first saw operator should cut along the edge of the fire throwing the burned material back into the burn. Subsequent saw teams cut along the edge removing green unburned fuels. Example C