UL 62841-4-1-2020 pdf download – Electric Motor-Operated Hand-Held Tools, Transportable Tools And Lawn And Garden Machinery – Safety – Part 4-1: Particular Requirements For Chain Saws.
8.14.1.101 Safety instructions for chain saws 1) General chain saw safety warnings: a) Keep all parts of the body away from the saw chain when the chain saw is operating. Before you start the chain saw, make sure the saw chain is not contacting anything. A moment of inattention while operating chain saws may cause entanglement of your clothing or bodywith the sawchain. b) Always hold the chain saw with your right hand on the rear handle and your left hand on the front handle. Holding the chain saw with a reversed hand configuration increases the risk of personal injuryand should neverbe done. c) Hold the chain saw by insulated gripping surfaces only, because the saw chain may contact hidden wiring or its own cord. Saw chains contacting a “live” wire may make exposed metal parts ofthe chain saw “live”and could give the operatoran electric shock. d) Wear eye protection. Further protective equipment for hearing, head, hands, legs and feet is recommended. Adequate protective equipment will reduce personal injury from flying debris or accidental contact with the sawchain. e) Do not operate a chain saw in a tree, on a ladder, from a rooftop, or any unstable support. Operation ofa chain saw in this mannercould result in serious personal injury. f) Always keep proper footing and operate the chain saw only when standing on fixed, secure and level surface. Slippery orunstable surfaces may cause a loss ofbalance orcontrol of the chain saw. g) When cutting a limb that is under tension, be alert for spring back. When the tension in the wood fibres is released, the spring loaded limb may strike the operator and/or throw the chain saw out ofcontrol. h) Use extreme caution when cutting brush and saplings. The slender material may catch the saw chain and be whipped toward you orpull you offbalance. i) Carry the chain saw by the front handle with the chain saw switched off and away from your body.
2) Causes and operator prevention of kickback: Kickback may occur when the nose or tip of the guide bar touches an object, or when the wood closes in and pinches the saw chain in the cut. Tip contact in some cases may cause a sudden reverse reaction, kicking the guide bar up and back towards the operator. Pinching the saw chain along the top of the guide bar may push the guide bar rapidly back towards the operator. Either of these reactions may cause you to lose control of the saw which could result in serious personal injury. Do not rely exclusively upon the safety devices built into your saw. As a chain saw user, you should take several steps to keep your cutting jobs free from accident or injury. Kickback is the result of chain saw misuse and/or incorrect operating procedures or conditions and can be avoided by taking proper precautions as given below: a) Maintain a firm grip, with thumbs and fingers encircling the chain saw handles, with both hands on the saw and position your body and arm to allow you to resist kickback forces. Kickback forces can be controlled by the operator, if proper precautions are taken. Do not let go ofthe chain saw. NOTE Figure 103 may be used as an illustration in the instruction manual for holding the machine properly. b) Do not overreach and do not cut above shoulder height. This helps prevent unintended tip contact and enables bettercontrol ofthe chain saw in unexpected situations. c) Only use replacement guide bars and saw chains specified by the manufacturer. Incorrect replacement guide bars and saw chains may cause chain breakage and/or kickback. d) Follow the manufacturer’s sharpening and maintenance instructions for the saw chain. Decreasing the depth gauge height can lead to increased kickback.