Scaffolding Your Key to Stability Presentation-Scaffolds-Posted... · 1 Scaffolding Your Key to...
Transcript of Scaffolding Your Key to Stability Presentation-Scaffolds-Posted... · 1 Scaffolding Your Key to...
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Scaffolding Your Key to Stability
Presented By: Georgia Tech
Presented By: Georgia Tech
Continuing Education
• According to OSHA (the Occupational Safety and Heath Administrations), close to 2.3 million construction employees work on scaffolding on a regular basis.
• Approximately 4,500 construction workers suffer serious and often fatal injuries each year due to improper scaffolding safety precautions and employer negligence.
• AVOID BECOMING A STATISTIC.
Scaffolding Injuries
• According to BLS, an average of 50-89 construction workers are killed each year from falls related to the use of scaffolds.
• In the past six months (October 2012-March 2013), There have been at least 15 fatalities.
• Falls from ladders and scaffolds account for 40% of all fall related injuries.
More Statistics How Can Georgia Tech Assist?
Georgia Tech Safety and Health Consultation Program
Onsite Consultation
Brief Training (1-2 hours)
OSHA Training Institute
GA Tech Scaffold Training Course
• When OSHA revised its Scaffolds standard in 1996, Bureau of Labor Statistics studies showed that 25 percent of workers injured in scaffold accidents had received no scaffold safety training, and 77 percent of scaffolds were not equipped with guardrails.
Importance of Scaffolding Safety
Inspection Targeting – CSHO will stop and perform inspections where employees are observed exposed to a fall hazard greater than 10 feet.
Compliance Assistance – Outreach activities will be conducted to promote employer and employee awareness of fall hazards, requirements and this LEP.
Compliance Activity
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Subpart L - Scaffolds (1926.450 - 454)
1246
1160
1108
1029
875
453(b)(2)(v)
451(g)(1)
451(e)(1)
451(b)(1)
454(a)
Sta
nd
ard
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92
6.
Scaffolds above 10 ft. - Fall protection
Access
Scaffold platform construction
Aerial lifts - Body belt & lanyard
Training for use of scaffolds
GA Ranked Scaffold Hazards
Ranking Condition
1. 29 CFR 1926.451(g)(1)
Scaffolds-Fall Protection
8. 29 CFR 1926.451(b)(1)
Scaffold-Platform
6. 29 CFR 1926.451(c)(2)
Scaffold-Footing
Hazards
There are numerous hazards associated with scaffolds:
Falls from elevation
Collapse from overload or instability
Electrocution
Bad planking giving way
• A competent person is a person on the project who has knowledge to identify and the authority to correct site hazards
• OSHA 10 or 30 hour training card could support the fact you had training and are knowledgeable
• The 10 or 30 hour OSHA training card alone does not necessarily mean you are a competent person
Requirements for Competent Person
• Scaffolds have to be inspected daily by a competent person
• Scaffolds must be erected, moved, dismantled or altered under the supervision of a competent person
• Work by qualified workers selected by the competent person
Requirements for Competent Person
• The competent person must be on the project to direct the activities of the personnel during erection, moving, or dismantling of the equipment.
• Determine the use of fall protection during the set up of scaffolds
Competent Person
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Each scaffold and scaffold component must be capable of supporting
Non Adj.:4X non adjustable
Adj.: Stall load of hoist not to exceed 3X rated load
Scaffolds must be designed by a qualified person and loaded accordingly.
Capacity 29 CFR 1926.451(a)
All working levels of scaffolds are required to be fully decked.
No gaps greater than one inch allowed
Each scaffold platform shall be at least 18 inches wide.
Ladder jack, roof bracket and pump jack can be 12 inches wide.
The front edge shall not be more than 14 inches from face
The end of each platform will extend over the center line by at least 6 inches
Platform Construction 29 CFR 1926.451(b)
Each member must rest on its own support system
On direction changes, platforms that rests on a bearer at an angle other than a right angle must be laid first
Platforms that rest at right angles over the same bearer laid second
Requirement for over hang based on length:
10 ft or less platform not to exceed 12 inches
More than 10 ft not to exceed 18 inches
For extended platforms overlap over supports by 12 inches (unless secured)
Wood platforms shall not be covered with opaque finishes.
Components (different) shall not be mixed unless they fit (integrity maintained).
Platform Construction Platform Construction-Unacceptable Gaps
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Platform Construction Platform Construction-Fully Decked
Scaffolds with a width to height of more than 4:1 need to be restrained
Guys, ties, and braces installed in accordance to manufacturer
Ties, guys, wires must be used for eccentric load
Supported poles, legs, and posts need to bear on base plates and mudsills or other firm foundation.
Footing must be rigid and sound.
No unstable objects for supports or platform.
Legs, posts, frames must be plumb and braced to prevent swaying.
Supported Scaffolds, 29 CFR 1926.451(c) Scaffold-Restraining
Guys, tie, and braces must be installed in accordance with manufacturer’s instructions or at closest member 4:1 ration and repeated:
20 ft or 26 ft-Vertical
30 ft Horizontal
Supported Scaffold-Footing Supported Scaffold-Unstable Objects
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Scaffolding-Overhead Power Lines
29 CFR 1926.451(f)(6)
*Some options are available to contractors who have no choice but to work within the 10 foot zone.
1. Only after the utility company or electrical system operator has de-energized the lines,
2. relocated the lines, or
3. installed protective coverings.
When scaffold platforms are 2 feet above or below a point of access ladders, stair towers or personnel hoist must be used.
Cross braces can not be climbed.
Ladders set up so not to tip scaffold.
Stairway type ladders can be used in 1926.451(e)(3)
Railing has to be provided
Ramps 1926.451(e)(5)
Rails over 6 feet
No slope greater than 20 degrees
Scaffold Access, 29 CFR 1926.451(e)
Integral prefabricated scaffold access frames:
Designed and constructed as ladder rungs
Rung length of 8 inches
Uniform space
Direct Access shall only be used when scaffold is not more than 14” horizontal and 24” vertical away.
Safe means of access shall be provided during erecting or dismantling as determined by competent person.
Scaffold Access Scaffold Access
Scaffold Access
Scaffolds shall not be excessively loaded
Inspection by competent person before each shift
Damaged scaffold immediately repaired or replaced.
Maintain adequate distance from power lines (3 ft for less than 300 V and 10 ft for greater than 300)
Must not work on slippery platforms, debris or during high winds.
Standing on objects to increase height prohibited.
Ladder may be used on wide area scaffold.
Scaffold Use 1926.451(f)
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Scaffold Use
Scaffolds must be inspected before use each shift by competent person.
All damaged components must be repaired or replaced immediately.
Required on all scaffolds greater than 10 feet.
Boatswains chair,float scaffold or similar require fall arrest.
Suspension scaffold requires rails and fall arrest system (independent life line).
Rail system design:
Top rail installed between 38 and 45 inches
mid rail between top and working surface
Finished components must with stand:
A force 200 pounds for top rail
150 pounds for mid rail
Fall Protection, 29 CFR 1926.451(g)
Guardrails must be free of sharp edges.
Ends of rails must be constructed so it does overhang the terminal posts
Steel or plastic bands are not acceptable as railing
Cross brace may be used as a mid rail if it meets the height requirement (cross between 20-30 inches)
Falling object requirements are:
Employees on scaffold(in addition to hard hats) must be protected by toe boards, debris nets or canopy
Area below must be protected by barricades, canopies, toe boards on scaffolds over 10 feet
Toe boards- withstand 50 pounds of force and be 3.5 inches wide.
Fall Protection Fall Protection-Cross braces can not be used as a top rail
Fall Protection
Tube and coupler:
The existing platform shall not be moved until bearers are set
X bracing installation
Couplers have to made of structural steel
Scaffolding over 125 ft. have to be designed by registered engineer
Fabricated Frame:
The existing platform shall remain until the frames are set/braced
Frames and panels shall be braced (joined with stack pin
Scaffolding over 125 ft. have to be designed by registered engineer
Additional Scaffolds-Supported, 29 CFR 1926.452
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Tube and Coupler Scaffold
• Traverse bracing at the end of scaffold at least:
• Every third set of posts horizontally (measured from only one end), and
• Every fourth runner vertically. [1926.452(b)(2)]
• Bracing must extend upward diagonally to opposite sides of the scaffold, such as from the inner posts or runners to the next outer posts or runners, or vice versa.
Tube and Coupler Scaffolding
Horse scaffolds:
Limited to two tiers (10 ft.)
Horses arranged directly over each other
Legs nailed down and tiers braced
Crawling boards:
Extend from peak to eaves and secured to roof by ridge hooks or equivalent
Pump jack scaffolds:
Bracket must have two positive grips
Poles secured at the top and bottom
Work bench is not a platform
Continuous length poles joined at seam parallel to bracket
Mending plates must be installed at 2X4 splices for strength
Additional Scaffold-Supported Pump Jack Scaffold
Ladder jack scaffolds:
Not to exceed 20 feet
Ladder meet requirement of part X
No bridging of platform
Ladders must be provided with device to prevent slipping
Constructed to bear on side rails and rungs or rungs (if rungs at length of 10 inches)
Window jack scaffold:
Attached to window opening and not used to place planks between scaffolds
Step, trestle, and ladder scaffolds:
Platform not placed higher than second highest rung and ladder secured
Ladders designed to part X
Additional Scaffolds-Supported Improper Ladder Scaffold
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Swing Stages:
Platform limited to 36”
Platform must be securely fastened to hangars
Platforms shall be of the ladder, plank, or beam type
Two point scaffolds shall not be bridged together unless bridged and hoist is appropriately sized
Multi level scaffolds:
Equipped with independent support lines (equal to number of suspension points) and not attached to the same point as suspension ropes
Supports for platform attached to stirrup only
Additional Requirements-Suspended
Requirements for mobile scaffolds:
Adequately plumbed, braced, level and squared
Must have means to lock wheels/casters
Force to move scaffold no higher than 5 feet above support surface
Power system must be designed for scaffold
Stabilized to prevent tip
Platform must not extend base support without outriggers
Caster stems-pinned
Riding not allowed unless:
surface floor level and free of debris and 2:1 BXH ratio
Outriggers on both sides
No one allowed on extended platform
Additional Requirements-Mobile
Additional Requirements-Mobile
Note outriggers on both sides because scaffold exceeds 2:1 base to height ratio
Guardrails and toe boards required 10 feet
• Only to be used on large area scaffold
• Surfaces must be flat and free of pits
• No obstructions
• Stilts have to be maintained
• Guardrails must be raised by an amount equal to stilts
Additional Requirements-Stilts
Suspended scaffolds
Suspended scaffolds are platforms suspended by ropes, or other non-rigid means, from an overhead structure
Single-point adjustable
Supporting rope between scaffold and the suspension device must be kept vertical unless:
Rigging has been designed by a qualified person
Scaffold is accessible to rescuers
Support rope is protected from rubbing during direction changes, and
Scaffold is positioned so swinging cannot bring it into contact with other surfaces
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Two point swing stage
• Platform limited to 36”
• Platform securely fastened to hangars
• Platforms must be of ladder, plank or beam type
• Must not be bridged together unless bridge and hoist is appropriately sized
Meet the design criteria of ANSI
Aerial ladders must be secured in lower traveling position by a locking device before it is moved.
Ext./Art. Platforms:
Boom must be adequately stowed before move
Insulated portion must not be altered
A body belt or harness and lanyard must be used
Employees must stand on floor of basket
Never exceed load capacity
Lift truck shall not be moved with men in basket unless adequately designed (upper controls-personnel carriers)
Brakes set for outrigger use (wheels chock)
Requirements for Aerial Lifts 29 CFR 1926.453
Fatal Fact
Employee was operating an aerial lift, with an extendable boom rotating work platform.
The boom was fully extended and the machine apparently ran over some bricks, causing the boom to flex or spring, throwing the employee from the basket
The employee fell 37 feet to a concrete surface.
• Extensible and articulating platforms:
• Lift controls must be tested each day
• Authorized employees only
• No belting off to adjacent structure
• All pneumatic and hydraulic components comply with ANSI A92.2-1969 and non critical parts must have burst factor 2:1.
Aerial Lifts
Training-General 29 CFR 1926.454
Employees must receive training from qualified person that includes:
Nature of electrical, fall, and falling items
Use of scaffold/handling
Maximum intended load and load carrying capabilities of scaffold
Methods for dealing with electrical hazards and fall protection system
Requirements of sub L
Training-Setup or Dismantling
Employees must be trained in:
Nature of scaffold hazards
Procedures for setup, dismantling or moving the system
Design criteria, maximum intended load carrying capacities and use of scaffold
Requirements of subpart L
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• When the employer has reason to believe an employee lacks the skill or understanding needed for safe work involving scaffolds, retraining shall be performed until proficiency is regained. Retraining is required:
• When additional or new hazards exist.
• Changes in the type of scaffold and fall protection exist.
• Where there are inadequacies in an employee’s work.
Training-Need for Retraining