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Fall Protection Rebar and Concrete Formwork

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Fall Protection Rebar and Concrete Formwork Oregon Occupational Safety & Health Division (OR-OSHA) FALL PROTECTION ■ Rebar and Concrete Formwork Contents Introduction ........................................................................................... 2 OR-OSHA's Fall Protection Requirements for Construction Work: 1926 Subdivision M ................................................ 2 Fall protection requirements for rebar and concrete formwork ................................................................................. 3 Personal fall-arrest systems ....................................................................... 3 Safety-net systems...................................................................................... 3 Positioning-device systems ....................................................................... 4 Climbing rebar.......................................................................................... 5 Capping rebar ........................................................................................... 6 Standard formwork................................................................................... 6 Slipforms ................................................................................................... 7 Tilt-up work ............................................................................................... 7 Precast concrete........................................................................................ 7 Exterior building work ............................................................................. 8 Ladders...................................................................................................... 8 Protective equipment ............................................................................... 8 Training .................................................................................................. 9 Retraining ................................................................................................. 9 Training records ..................................................................................... 10 Emergencies ..........................................................................................11 Responding to emergencies .................................................................. 12 Investigating accidents ........................................................................... 12 Definitions of selected terms .................................................................13 OR-OSHA services ................................................................................16 1 FALL PROTECTION ■ Rebar and Concrete Formwork Introduction Fall protection is a concept that describes behaviors, systems, processes, procedures, equipment, and rules intended to protect workers from fall hazards. Fall protection doesn’t mean bulky or cumbersome equipment. It doesn’t interfere with work tasks and it doesn’t get in the way of coworkers if you understand the concept and apply it appropriately. That’s the pur- pose of this manual: to help you use appropriate fall protection for rebar and concrete formwork. OR-OSHA’s fall protection requirements for construction work: 1926 Subdivision M OR-OSHA’s fall protection requirements for the construction industry are included in OAR 437, Division 3, Subdivision M, of the Oregon construc- tion safety and health code. The requirements apply to virtually all walking and working surfaces in construction workplaces. Subdivision M specifies: • Where fall protection is required. • What fall protection systems and methods are appropriate to use. • Correct construction and installation practices for fall protection. • Supervision requirements for workers using fall-protection. • Safe-work procedures and requirements with fall-protection systems. • Training requirements for workers using fall protection. 2 FALL PROTECTION ■ Rebar and Concrete Formwork Fall-protection requirements for rebar and concrete formwork Division 3, Subdivision M, requires workers on the face of formwork or reinforcing steel to use fall protection if they are six feet or more above a lower level. Workers and employers can choose from among the following types of fall protection: personal fall-arrest systems, safety nets, or positioning-device systems. Personal fall-arrest systems Personal fall-arrest systems are designed to stop a worker from free falling to a lower level. A personal fall- a a arrest system consists of an anchorage, connectors, and a a a a aa a a aa a a a aa a full body harness. a a a a a aa a a a a a a a a a a aa a a a a a Other system components may include a lanyard, a a a a a a a a a a a a aa aa a aa a a lifeline, and a deceleration device. These components a a aa a a a a a aa a a must be used only for fall protection and not for any a a a aa a a a other purpose. If the system, or any system component, a a a aaa aa a a is subjected to a fall, it must be immediately removed a a aaa a a aa from service and cannot be used again until a competent A personal fall-arrest system person determines it is undamaged. Who is a competent person? OR-OSHA defines a competent person as one who is capable of identifying existing and predictable hazards in the work environment and who has authorization to take prompt measures to eliminate the hazards. Use a personal fall-arrest system as fall protec- tion when you are constructing standard forms or doing dismantling work, exterior building A safety-net system work, or erecting precast concrete members. Safety-net systems Safety-net systems consist of mesh nets, panels, connectors, and other impact-absorbing components. Use safety nets as fall protection for doing standard formwork, slipform work, and erecting precast concrete members. a a aa a a a 3 FALL PROTECTION ■ Rebar and Concrete Formwork Positioning-device systems A positioning-device system Positioning-device systems are the most appropriate type of personal fall-protection for working on and placing rebar. A positioning-device system enables one person to work on a vertical surface with both hands free and it limits free-fall distance to two feet or less. The difference between a positioning device system and a personal fall-arrest system is that a positioning-device system supports a worker on an elevated surface and limits a fall to two feet. A personal fall arrest system, on the other hand, prevents a worker from free falling more than six feet. The major components of a positioning-device system are: Body support — a body belt or full body harness. Connectors and connecting assemblies — a chain/ web rebar assembly or rope/web lanyard, snaphooks, and D-rings. Anchorage connector — a carabiner or snaphook. Anchorage — a rebar or other support structure. Full body harness with adjustable Positioning-device systems must meet the following front D-ring requirements: Body support A body belt must limit the maximum arrest force on a worker to 900 pounds and can’t be used for any purpose other than personal fall protection. A body harness must limit the maximum arrest force to 1,800 pounds and must be used only for fall protec- tion. Make sure the body belt or harness has side D-rings, or a single front D-ring for positioning. (Rear D-rings are for fall arrest only.) Finally, use a body belt or full body harness that is properly fitted; belts and harnesses come in different sizes. Body belts must not ride up and compress the rib cage. 4 FALL PROTECTION ■ Rebar and Concrete Formwork Connectors and connecting assemblies Connecting assemblies must have a minimum tensile strength of 5,000 pounds. Snaphooks and D-rings must be proof-tested to a minimum A connecting assembly tensile load of 3,600 pounds without cracking, deforming, or breaking. They must be made of drop-forged steel or equivalent materials, the finish must be corrosion-resistant, and the sur- faces smooth. The dimensions of snaphooks must be compatible with the members to which they are connected or the snaphooks must be of the double-locking type to prevent roll out. Anchorage Positioning-device systems must be secured to an anchorage that can support at least twice the potential impact load of a worker’s fall or 3,000 pounds, whichever is greater. Be sure to inspect positioning device systems for wear, damage, or deterioration before using them. Remove defective components from service. Climbing rebar OR-OSHA permits you to free-climb concrete forms and rebar to reach work areas. The maximum free-climbing height is 24 feet. The horizon- tal bars must be spaced not less than six inches, or more than 16 inches on center. When rebar spacing is more than 16 inches Avoid climbing overhanging rebar or formwork. If you on center, use a ladder or lift to reach work have to work on overhanging objects, use a powered areas. Upon reaching a work area, you elevated lift or ladder. must use a personal fall-arrest system, safety net, or positioning-device system for fall protection. Check the rebar’s rigidity before climbing it. If it’s not rigid, brace it to meet the required 3,000-pound anchor- load requirement. Avoid climbing overhanging rebar or forms (see the figure at right). This type of climbing increases your risk of falling and overexerting your muscles and joints. 5 FALL PROTECTION ■ Rebar and Concrete Formwork Capping rebar Whenever you work above rebar that protrudes from the floor, cover the rebar with protective caps that will prevent you from being im- paled if you fall. Cap rebar protrud- ing horizontally to prevent scrapes, Capped rebar cuts, or eye injuries. Standard formwork
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