437-007-0810 Manual Falling (1) Falling cuts must not be made in a standing tree while anybody is in the area where the tree could fall. (2) Trees must not be felled if the wind is strong enough to prevent the tree from falling in the desired direction. (3) Domino falling is prohibited. EXCEPTION: A lodged tree can be dislodged by falling another tree into it. (4) A worker must not: (a) Work under a lodged tree. (b) Cut a tree that another tree is lodged in. (5) When any lodged or standing tree with undercuts or back cuts is left unattended, the hazardous area must be distinctly marked by hazard identification ribbon as specified in OAR 437-007-0205. (6) Only qualified workers may fall danger trees. (7) When falling danger trees: (a) Use extra caution. (b) Remove loose bark within reach from the ground before starting to fall the tree. (c) Use a deep undercut with a wide face opening, and fall the danger tree in the direction of lean whenever possible to avoid vibration caused by wedging. (8) One worker must not fall a tree or danger tree when the assistance of another worker is necessary to minimize the risk of injury caused by overhead hazards, loose bark, loose or interlocked limbs, conditions of the tree, terrain or cutting conditions. (9) An escape route must be determined and arranged before a tree is fallen so the worker(s) falling the tree can move at least 25 feet away from and to the side of the base of the tree. (10) The escape route must be clear of brush, snow, tools and other material that would impede a quick escape. (11) Workers must not remain at the stump as the tree falls unless it is necessary to complete the backcut. Once the backcut is completed, the worker must immediately release the throttle and move a safe distance away from the tree. (12) Trees must be felled into the open whenever practical. (13) When manual falling or tree jacking, trees must not be felled directly uphill when the probability of the tree sliding back past the stump is likely. (14) When manual falling or tree jacking, trees felled uphill must be quartered to the slope, to minimize exposure to sliding or rolling trees. (15) When trees or snags are over 6 inches DBH: (a) Undercuts must not be less than 1/4 the diameter of the tree. (b) Face openings must not be less than 1/5 the diameter of the tree. EXAMPLE: Acceptable undercuts: A. Conventional undercut. Can be made with parallel saw cut and axe diagonal cut or both cuts with the saw. Generally used on trees of small diameter. Figure 7-35 — Falling — Conventional Face B. Humbolt cut. Both cuts made with the saw. Same as "A" except that waste is put on the stump. Figure 7-36 — Falling — Humbolt Face C. Open face cut. Both cuts made with the saw. The top and bottom face cuts generally form a 90 degree angle when completed. Works best on small diameter trees. Figure 7-37 — Falling — Open Face [Figures not included. See ED. NOTE.] (16) Undercuts must be completely removed and cleaned out unless it is necessary to use a Dutchman on either side of the cut. (17) Undercuts and back cuts must be made at a sufficient height above the highest ground level to enable the person falling the tree to: (a) Safely make the cut. (b) Control the tree. (c) Have freedom of movement for a quick escape. (18) Back cuts must be made above and on a horizontal plane with the face cut. (19) Holding wood must not be completely cut through. NOTE: When completing a swing cut, sufficient holding wood must be maintained to guide the tree during most of its fall. [ED. NOTE: Figures referenced are available from the agency.] Statutory/Other Authority: ORS 654.025(2) & 656.726(4) Statutes/Other Implemented: ORS 654.001 - 654.295 History: OSHA 5-2003, f. 6-2-03, cert. ef. 12-1-03