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Chain Saw Safety Wayne Fisher, Extension Safety Specialist, University of Idaho Any chain saw can be as savage as a shark to those who mis handle it. If you want to get the best out of your chain saw without being bitten, always treat it with real respect. If you are a beginner or an occasional user, do not try to act like a full-time professional who can safely do things with a chain saw which would land the novice in a hospital. Felling, limbing, bucking and trimming trees can all be hazardous tasks if not done with due care. Safety Preparation Safety begins before actual work begins. Protect eyes, head, ears, feet and hands with: - hard hat or bump cap - safety glasses or goggles--flying wood chips can injure eyes - trim-fitting trousers, shirts and jackets to reduce chance of clothing tangling in saw - avoid scarves, long skirts--tie back long hair - light non-slip gloves to protect hands from abrasions and wood cuts - nylon protective leg chaps - footwear with good grip to prevent falls--boots will protect lower legs; steel toe safety boots will protect toes - protective devices against the 1 00-decibel or higher saw noise level. Good ear muffs or comfortable molded ear plugs will allow a full work day without ear damage and fatigue. If ears ring for an extended time after sawing, hearing damage may have occurred. The unprotected user should limit his oper ating time to one hour per day maximum. - a chain saw sized to fit the task. Start chain saw engine by setting saw on firm ground with chain out of gear and free of obstacles, placing right foot in loop of rear NON-SLIP SHOES handle, pressing left hand down on upper handle and pulling a COVER (S~ ~ ANDGa starter rope straight up witli right hand. Over-oiling of chain increases accumulation of flammable SAFETY - . SAFETY ~ (J lJ material on the saw. Proper adjustment of chain oiler will help " HARD" HAT HEARING PROTECTION DEVICES GOGGLES prolong chain life and insure good performance. When automatic Protective equipment is mandatory for operator safety. chain oiler over-oils it may run dry before the next refueling stop. Main Hazards Saw-related backup equipment is essential. Shovels and fire Chain saw accidents stem from both direct saw contacts and extinguishers are required by law in some forests. A three-gallon, related non-contact situations. A Swedish study shows only 30% pressure-type garden sprayer with a special medium spray pattern of tree felling injuries are due to direct saw contact; 40% are non tip mal<es a good extingui-s-her for forest conditions. Dry chemical saw contact accidents caused by limbs, split pieces, springing of AB class extinguishers are also good. Other backup tools should trunk, tree slipping off stump, or operator falling, being caught include axe, sledge and wedges. A saw case or protective chain between sharp edges other than the tool, etc. scabbard reduces damage to sharp chain during transport. Fuel Two of every three accidents to casual operators and helpers and chain oil containers should be sturdy and spill-proof. or bystanders are caused by inadvertent contact with the moving chain according to a recent Consumer Product Safety survey. Study Owner's Manual In these accidents, the operator makes a careless move such as The owner's manual should be understood before the saw is reaching across or holding work near the moving saw, or loses used. Ask your dealer to answer questions about any details you saw control allowing it to come in contact with body. Loss of do not understand. Essential maintenance tools include sharpen balance due to loss of footing and subsequent loss of saw control ing file for dressing the chain, and screwdriver and wrench for accounts for one of every six accidents. Hazard awareness can making needed throttle and clutch adjustments. Throttle adjust sharply reduce the incidence of injury. ment should be such that engine operates at recommended speed Kickback is a major chain saw hazard. In kickback, the upper during sawing and chain clutch disengages immediately on re chain "grabs" in the wood or an obstruction and forces the saw lease of throttle trigger. Chain tension should be adjusted to backward, causing operator to either lose control of saw or lose insure quick, smooth cutting--too loose a chain will derail; too tight his balance, bringing saw into contact with his body. Loss of a chain will bind. All chains stretch with use. Most of this stretch balance often causes him to reach into the running saw chain as will occur during first half hour of operation. he grabs to steady himself. Extension Bulletin 0727 Cooperative Extension Washington State University Pullman Issued by Washington State University Cooperative Extension, J. 0. Young, Director, and the U.S. Department of Agriculture in fur therance of the Acts of May 8 and June 30, 1914. Cooperative Extension programs and employment are available to all without discrimination. Published June 1980. A chain can lock or a saw can kick back for many reasons. power supply line will help prevent fatal shocks. The soil should Watch for these kickback causes: be relatively dry and damp foliage should be avoided. Lay cord out • Abrupt change in wood characteristics, i.e., green to dead in a manner which will not interfere with work--it should not be • Running saw too slowly underfoot to cause tripping, or placed where it could be cut by e Build-up of damp sawdust saw. Ample cord length will allow operator to keep cord at his • Twig caught in chain and jamming against work right and strung behind him. Check to be sure saw switch is in off e Branch or obstruction on opposite side position before completing electrical connection. Unplug power e Twisting of saw--cutters grabbing wood before making adjustments and when saw is not in use. e Sawing with point of guide bar (nose sawing) Hold saw firmly with both hands in proper position when e Closing kerf. cutting. Make sure thumbs and fingers completely encircle saw Kickback is almost certain under certain conditions. Cutting handle. Always keep elbows and knees flexed for maximum con with upper side of bar may be convenient but is dangerous, especi trol. Operate saw to side of body so it will not swing into body if it ally with larger, more powerful saws. If chain locks when saw kicks back, comes out or through unexpectedly. Never shift hand is used in this position, sudden kickback will throw saw backward positions or cross arms for easing strain or better reach. and perhaps injure operator. Always have a firm grip on saw and Cut with lower side of saw as much as possible. This is safest, keep body well balanced and in position such that loss of control least tiring position. Keep bumper or work teeth against wood will not mean disaster. when cutting with lower side. Having saw blade fully into wood allows for better control. Keep guide bar in middle of cut (kerf) so cutters on opposite side will not hang up. Guide saw into wood. General Safety Procedures Do not twist guide bar. Keep chain properly sharpened--a wide Fire hazards with chain saws are numerous. The chain saw kerf, fine sawdust instead of chips and a need for force indicates operator should check the fire index before entering the forest. a sharpening is due. A crooked kerf may be due to sharper cutters Working conditions where fire danger is high demand extreme on one side of chain. Never allow running chain to contact ground precaution. The air-cooled engine head and muffler are hot and or metal--one such contact can dull chain more than cutting exposed. Type fuel used, frequent refueling, and spillage associ dozens of trees. ated with the hot engine complicate the problem. Sawdust should Many newer saws have a chain brake--a device actuated by be brushed from the motor regularly. Oily sawdust accumula operator's hand to apply a brake when reverse motion of saw tions can easily ignite, drop off, and start a fire. Hot exhaust sparks occurs. The brake is not effective in the horizontal position, as directed into tinder can cause ignition, as can sparks from the when felling a tree, and is not always activated if operator loses high speed steel chain striking a stone. his grip on upper hand hold. Refuel saw when it has cooled and is in a clear area to avoid spills onto leaves, needles or sawdust. Gradually release pres Felling Procedures sure in fuel tank before removing cap completely. Use proper Have saw in top operating condition. Never attempt to cut a funnels and spouts to prevent spills and a fuel can small enough tree with a diameter greater than the length of the chain saw for easy handling. Leave recommended expansion space in tank. blade. Be certain once felling operation is started that saw will Never smoke while refueling. Fill chain oil carefully with a dis function to completion. Knowing that saw is performing properly penser bottle. allows operator to focus all attention on felling procedure. Consider particular characteristics of each tree felling project. One tree may lean; another tree might be unbalanced due to uneven top growth or breakage even though trunk does not lean. Large diameter branches are good indicators of unbalance. Pre vailing wind direction affects tree growth and balance. Fall direc tion is affected by present wind conditions. The inexperienced operator should never attempt to fell trees on windy days. Clear ground around base of tree of limbs; remove under brush and other obstructions.