22 The Mainline Safety & Health ii. Purpose-Built vs. Modified Equipment Some manufacturers design purpose-built steep slope harvesters and forwarders, while others offer aftermarket kits to modify existing logging machinery. Purpose-built units often have specialized frames, reinforced tracks, or hydraulic systems specifically designed for steep terrains. iii. Advantages › Safety: By preventing uncontrolled movement on steep slopes, winch-assisted systems reduce worker injuries, accidents and equipment rollovers. › Productivity: Operations can continue even on slopes that might otherwise be inaccessible, maximizing harvestable timber. › Efficiency: Reduced reliance on manual felling and/or cable yarding can improve overall productivity and help to solve the task of finding and retaining a workforce. 2. Key Considerations for Safe Operations i. Site Assessment Thorough evaluations—such as measuring slope gradients, soil type, and potential weather impacts—are essential. ii. Equipment Selection and Maintenance Using a well-maintained, purpose-built or properly retrofitted machine with a reliable winch system is critical. Regular inspections of the cable and anchor points are vital for safety. iii. Operator Training Specialized training ensures that operators understand the capabilities and limitations of their equipment, as well as the correct procedures for engaging and disengaging the winch system. iv. Regulatory Compliance › Tethered Variance: The OR-OSHA “2022 Revised Tethered Logging Research Variance Provisions” provides the rules that forest tethered operators must follow while working on steep slopes in Oregon. › Line Inspection (OR-OSHA Guidance): Amongst other rules found within the variance, OR-OSHA specifies requirements for tether lines to ensure ongoing safety: » Continuous Wire Rope: Tether lines must be one continuous piece of wire rope (not spliced) and have a rated breaking load in accordance with the system manufacturer’s recommendations. » Repair or Replacement: Tether lines must be repaired (shortened) or replaced if there is evidence of chafing, With the 2025 AOL Convention concluding a few short weeks ago, and being the moderator for the seminar on “Rigging Gains and Innovation,” I thought I would take a deeper dive into steep slope logging. Steep slope logging—also referred to as “cable-assisted” or “tethered” logging—is an increasingly popular solution for harvesting timber on challenging terrain, and for reducing ground labor demands. Traditional ground-based operations become less feasible, more costly, and considerably more dangerous, as slopes exceed safe operating limits. Winch-assisted systems bridge this gap by providing equipment with extra traction and stability, helping operators navigate steep hillsides safely and efficiently. Tethering can assist a variety of functions in the harvest system, including: felling, bunching, processing, shovel logging, skidding, forwarding, or concentrating decks. Below, we explore the fundamentals of steep slope logging, from the underlying technology to best practices and leading equipment providers. 1. The Mechanics of Steep Slope Logging i. Cable-Tethering or Winch Assistance The fundamental idea is to use a high-strength cable attached to a winch. One end of the cable is anchored to a secure machine (i.e. purpose-built anchor machine) at the top of the slope, while the other end is fixed to the harvester or forwarder working on the slope. The tension in the cable provides additional support, preventing machinery from sliding downhill. Steep Slope Logging Winch Assist Enhancing Efficiency & Safety in Challenging Terrain ›By David Grim, Safety and Health Manager
RkJQdWJsaXNoZXIy Nzc3ODM=