Chainsaws

1. Chainsaws

2. Preparing to operate chainsaw • Check over chainsaw for faults. • Ensure adequate fuel/oil for the task. • Check chain tension (adjust as required). • Check sharpness of cutters (sharpen using correct sized round file). • Check rakers are at correct depth (file with correct sized flat file). • Correct PPE? Helmet/ear defenders/visor and eye protection/chainsaw trousers/chainsaw boots/chainsaw gloves/non-snag clothing/long hair tied back. • Site hazards – Risk Assessment • Escape routes. • Plan of work.

3. Pre-start checks on a chainsaw • Correct PPE. • Check saw for faults (loose bolts/screws etc.). • Safety features. • Chain/guide bar. • Fuel/oil.

4. Daily maintenance • Chain tension. • Chain sharpness. • Depth gauges. • Guide bar groove/oil holes/burrs. • Tightness of nuts/bolts/screws. • Operation of chain brake. • Air filter. • Spark plug. • Recoil starter spring. • Correct fuel mixture (50:1). • Clean debris from around fins, clutch etc. • Exhaust.

5. Cold Start Techniques • Place saw on firm, level ground. • Grip front handle firmly, with foot on rear hand guard. • Turn ignition switch on. • Engage choke lever. • Grip starter cord and pull sharply. • Once saw ‘coughs’, push in choke lever. • Pull starter cord to fire up saw. • Rev saw and check operation of chain brake. • Check saw oiling correctly. • Check chain does not ‘creep’ when idling – adjust chain tension or carburettor settings so chain is stationary.

6. Warm Start Techniques • Once saw is ‘warm’, re-start by gripping saw between knees, or place on ground and start as with cold start technique, but without choke. • Do not use ‘yo-yo’ technique as unsafe.

7. Re-fuelling • Re-fuel at location determined during site safety briefing (within designated work area, but clear from ‘drop zone’ etc.). • Clean debris/sawdust from around fuel caps before un-doing and removing. • Correctly mixed fuel should be stored in a labelled 5 litre plastic fuel container, with a non-spill pouring spout. • It is recommended to use a ‘spill tray’, to prevent contamination/pollution of the site. • Re-fuel chainsaw and re-fit fuel cap securely. • Top-up oil reservoir with appropriate chain oil and re-fit cap securely. • Check chainsaw for loose bolts, chain tension, chain sharpness etc.

8. Chainsaw Safety Features

9. Chainsaw Safety Features

10. Safety Features of a Chainsaw • Clearly marked on/off switch. • Chain catcher. • Chain Brake/Front Hand Guard. • Chain Breakage Guard (chain-catcher). • Rear hand guard. • Exhaust pointing away from operator. • Safety Labels. • Anti-vibration rubbers. • Safety Throttle. • Guide bar cover (sheath) for transportation. • Chain/bar combinations to reduce kickback.

11. Chainsaw Safety Features

12. Definition of terms • Snedding: removal of lateral branches from a conifer tree, using the smooth, flowing technique as used in NPTC assessment. • De-limbing: removal of lateral branches from a hardwood tree during breaking down of the crown (tension/compression reducing cuts etc.)

13. Tools to assist felling and cross-cutting operations • Plastic wedges • Hi-lift aluminium wedges • Steel wedges • Felling/turning bar • Timber tongs • Pull ropes • Hand winches

14. Hazards associated with tree felling operations • Falling debris (deadwood, hanging branches, hung-up trees). • Splitting stems (Barber’s Chair). • Trunk springing back when top hits ground. • Trunk rolling sideways (stand on upper side when cross-cutting). • Branches under tension/compression (spring back or trapping saw). • Tripping over debris (engage chain brake when moving around). • Kickback when operating chainsaw. • Flying debris getting in eyes (sawdust etc.)