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Fall Protection. Falls in Construction. Falls are the leading cause of deaths in the construction industry. Most fatalities occur when employees fall from open-sided floors and through floor openings.
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Falls in Construction Falls are the leading cause of deaths in the construction industry. Most fatalities occur when employees fall from open-sided floors and through floor openings. Falls from as little as 4 to 6 feet can cause serious lost-time accidents and sometimes death. Open-sided floors and platforms 6 feet or more in height must be guarded.
Fall Protection • We need to discuss: • The working conditions that prompt use of fall protection • Options that are available to protect workers from falls
Fall Protection • Workers should be able to: • List at least four methods of fall protection available for protecting workers • State the main criteria that prompts use of fall protection for construction workers
Frequently Cited Violations • Failure to protect workers from falls of 6 feet or more off unprotected sides or edges, e.g. floors and roofs. (1926.501(b)(1); (b)(10); and (b)(11)) • Failure to protect workers from falling into or through holes and openings in floors and walls. (1926.501(b)(4) and (b)(14)) • Failure to provide guardrails on runways and ramps where workers are exposed to falls of 6 feet or more to a lower level. (1926.501(b)(6))
Fall Protection Options Personal Fall Arrest System (PFAS) Safety Net Guardrails
Fall Protection Planning Lanyards and PFAS in use Fall protection systems and work practices must be in place before you start work.
Safety Line Anchorages Must be independent of any platform anchorage and capable of supporting at least 5,000 lbs. per worker
Guardrail Systems • Top rail, mid-rail, and toeboard • Top rail 42" (plus or minus 3 inches) • Toeboard minimum 3 1/2 inches high
Midrails • Required if no wall or parapet at least 21" high • Installed midway between top rail and working level • Screens & mesh run all along entire opening • Balusters, when used, not more than 19 ” apart
Guardrail Systems • Must withstand 200 pound force • Surfaced to prevent injury • No projection hazard at rail ends • All rails at least 1/4" thick 200 lb. of down & side force from 2"
Safety Nets Place as close as possible, but no more than 30 feet below where employees work
Safety Nets • Border rope strength of 5000 pounds • Extends sufficiently from outer edge • 400 pound drop test or certified by employer or CP • Objects removed within shift • Inspected weekly
Walkways & ramps Open sides & edges Excavations Concrete forms & rebar Holes Roofs Wall openings Bricklaying When Fall Protection is Needed • Residential Construction
Walkways and Ramps Guard ramps, runways, and other walkways
Residential Construction In residential construction, you must be protected if you can fall more than 6 feet
Unprotected Sides & Edges Unprotected edge Unprotected sides and edges must have guardrails or equivalent
Leading Edge Work This 1/4" nylon rope alone is not a proper way to guard this open floor
Warning Lines • Erected around all sides of roof • Erected at least six feet from edge if no mechanical equipment is used. • Consist of ropes, wires, or chains, and supporting stanchions • Flagged at least every six feet
Warning Lines • Lowest point (including sag) is no less than 34” • Resists 16 outwardly directed pound force at 30” • Only roofing work employees allowed between roof edge and warning line • Protect workers from mechanical equipment
Warning Lines • Points of access formed by two warning lines • When access not in use, closed off
Controlled Access Zones • Where leading edge and other operations are taking place the controlled access zone shall be defined by a control line • At least six feet from leading edge • Not more than 25 feet from leading edge
Controlled Access Zones • For precast concrete operations, CL six to sixty feet from edge • Extends entire length of leading edge • Connected at ends to guardrail or wall • Flagged or marked at least every six feet • 39 to 45 inches high • 200 pound breaking strength • Control line can be used instead of a guardrail along leading edge to protect workers
Safety Monitors • Must be CP to recognize fall hazards • Warns employees when: • Unaware of hazards • Acting in unsafe manner • Same surface and within sight • Close enough to be heard • No other responsibilities • Mechanical equipment not used where safety monitoring system being used.
Sky Lights This opening could be made safe by using a guardrail, or strong cover
Floor Holes Improperly Covered • Cover completely and securely • If no cover, can guard with a guardrail • Withstand twice expected load • Marked with ‘HOLE’ or ‘COVER’
Concrete Forms and Rebar • PFAS when working on formwork or rebar • Cover or cap protruding rebar
Excavations Guard excavations more than 6 feet deep when they are not readily seen because of plant growth or other visual barriers In addition to needing proper guarding, this excavation is not properly shored
Roofs If you work on roofs and can fall more than 6 feet, you must be protected
Wall Openings Wall opening If you work near wall openings 6 feet or more above lower levels you must be protected from falling
Good Work Practices • Perform work at ground level if possible Example: building prefab roofs on the ground and lifting into place with a crane • Tether or restrain workers so they can't reach the edge • Designate and use safety monitors (This is less desirable of all the systems) • Use conventional fall protection
Personal Fall Protection Systems • Work Positioning Systems • Restraint Systems • Suspension System • Fall Arrest
Work Positioning Systems These systems are designed to hold and sustain the user at a work location and limit the free-fall to two feet or less, as in rebar work or tree trimming.
Restraint Systems These are systems designed to prevent the user from reaching an area where free-fall could occur so no free-fall is possible, as in leading edge roof work.
Suspension System These systems support and suspend the user while being transported up or down vertically and will not allow a free fall.
Personal Fall Arrest These systems are designed to stop a free-fall of up to 6 feet, and limit the maximum forces of a user to 1800 pounds or less, as in steel erection or elevated maintenance work.
Use of Body Belts • Effective January 1, 1998, body belts are prohibited as a fall arrest device. • Body belts can still be used as a positioning device.
Common Pieces of Equipment Rope & Cable Grabs Self Retracting Lifelines Shock Absorbing Lanyard Carabiners Full Body Harness Cross-Arm Strap
Requirements for PFAS • Limit maximum arresting force on an employee to 1,800 pounds when used with a body harness; • Be rigged so that an employee can neither free fall more than 6 feet nor contact any lower level; • Bring an employee to a complete stop and limit maximum deceleration distance an employee travels to 3.5 feet; and • Have sufficient strength to withstand twice the potential impact energy of an employee free falling a distance of 6 feet or the free fall distance permitted by the system, whichever is less.
Calculate Total Fall Distance When using a shock-absorbing lanyard, it is important to understand how to calculate potential fall distance to avoid contact with a lower level. 1. When using a 6 ft. shock-absorbing lanyard and a full-body harness, first add the length of the shock-absorbing lanyard, 6 ft.; to the maximum elongation of the shock absorber during deceleration, 3-1/2 ft.; to the average height of a worker, 6 ft.
Calculate Total Fall Distance 2. Then, add a safety factor of 3 ft. to allow for the possibility of an improperly fit harness, a taller than average worker and/or a miscalculation of distance. 3. The total, 18-1/2 ft., is the suggested safe fall clearance distance, this is the height at which you must attach to an anchorage to minimize the risk of contact with a lower level. NOTE: If a higher anchorage is not accessible, a shorter lanyard or a fall limiter should be used.
Rescue Systems These systems which are designed to raise or lower a user to safety in the event of an emergency, so no free-fall is possible.
Rescue Systems Prolonged suspension from fall arrest systems can cause orthostatic intolerance, which, in turn, can result in serious physical injury, or potentially, death. Research indicates that suspension in a fall arrest device can result in unconsciousness, followed by death, in less than 30 minutes. To reduce the risk associated with prolonged suspension in fall arrest systems, employers should implement plans to prevent prolonged suspension in fall protection devices.
Rescue Systems OSHA recommends the following general practices: • Rescue suspended workers as quickly as possible. • Be aware of signs and symptoms of orthostatic intolerance. • Be aware that orthostatic intolerance is potentially life threatening. Suspended workers with head injuries or who are unconscious are particularly at risk. • Be aware of factors that can increase the risk of suspension trauma. • Be aware that some authorities advise against moving the rescued workers to a horizontal position too quickly.
Training Employers must provide fall protection training • The training is to teach you: • How to recognize hazards • How to minimize hazards The training must cover: • Fall hazards • Fall protection systems • Use of fall protection devices
Summary • If you can fall more than 6 feet, you must be protected • Use fall protection on: • walkways & ramps, open sides & edges, holes, concrete forms & rebar, excavations, roofs, wall openings, bricklaying, residential construction • Protective measures include guardrails, covers, safety nets, and Personal Fall Arrest Systems