IAGC LAND GEOPHYSICAL SAFETY MANUAL Edition 9 ... - CGISS

place the guard on the cutter bar before moving. Carry the saw with the bar facingbehind.10) Never carry the chain saw on your head.11) Start the chain saw only when it is placed firmly on the ground.12) Operate the chain saw only when stable footing is available. Do not stand downhillwhile cutting.13) Use the chain saw only when necessary.14) Chain saws should be fitted with a working chain brake, kill switch and kickbacksafety stop.15) Minimize the amount of vegetation disturbed, (e.g., no wider than 2 m or 6 feet).16) Helipads and drop zones may require the cutting of large trees. Local environmentalrestrictions need to be considered.17) Clearing the seismic line can normally be accomplished without removing treesgreater than 20centimeters (8 in.) in diameter.18) Leave in place smaller vegetation, low shrubs and grasses consistent with a safewalking surface.19) Remove leaners and hung up trees to prevent them falling unexpectedly later on.20) Do not build fires when the vegetation is dry.21) Do not fell trees across pipeline right of ways, trails or water courses.22) Try to cut and scatter limbs such that tree trunks fall flat on the ground. Good groundcontact speeds up decay.23) Where needed back-sighting is blocked by a branch, remove it rather than the wholetree.3.13.3 BridgingThe construction of rugged bridging is sometimes required to provide safe footing.The following types of bridging are recommended. Their measurements are given withtheir descriptions. Change these measurements as your situation dictates. Allmeasurements are guidelines. In some countries due to environmental reasons, slopebridging is not allowed. In these instances, specially trained and experienced people inthe use of ropes, harnesses, and other special tools are needed to climb or descendmountainous terrain.There are three types of bridges most commonly used:1) Swamp bridge.2) Mud flat bridge.3) Slope bridge.A poorly constructed bridge is far more dangerous than no bridge at all. If materials arenot available for a swamp type bridge, then use a mud flat-type bridge.Page 48 of 136