Supported Scaffold Safety

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Supported Scaffold Safety
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Objectives

• Familiarize yourself with
• Duties of a Competent person
• Basic scaffold requirements
• NOTE Links to the rule (WAC 296-874) and
  other resources are on a slide at the end of this
  presentation

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Some Supported Scaffolds
Supported scaffolds are scaffolds that are have
an attachment to the ground rather than are
suspended by cables.
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What is a Competent Person?

• A competent person is able to
• identify existing and
• predictable hazards
• identify working conditions
• that are unsanitary, hazardous
• or dangerous and
• has authority to eliminate hazards

NOTE This training does not make a person a
competent person as defined by the rule.
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Erecting and Dismantling

• A competent person determines feasibility of fall
  protection.
• Employer must provide maximum feasible fall
  protection.

• Questions to ask are
• Is there a nearby structure from which a
  lifeline can be dropped that the worker can tie
  off to?
• Can we install guardrails immediately after
  installing the fabricated frames and before
  moving to the next level?
• Can we sequence disassembly to keep the worker
  protected for the maximum feasible time?
• Whatever is feasible to do must be done during
  the assembly/ disassembly stages

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Inspection by a competent person

• Must occur at the beginning of each shift.
• After any occurrence which could affect a
  scaffold's structural integrity, such as
• adverse weather
• removal of parts
• damaged parts

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If you dont have inspections done
You might go to a jobsite some day and find this!!
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What do I have to do?

• Damaged or weakened parts must immediately be
• repaired, replaced, braced to meet minimum
  strength or
• removed from service until repaired.

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Or bad things can happen
The safety of a scaffold is highly dependent
upon being built right in the first place. You
should have regular inspections to make sure a
problem hasnt developed over time. When
scaffolds fail, they fail in a catastrophic way
and can cause many serious injuries or deaths
depending on who is on or around it when it fails.
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Worker must be trained on

• Recognizing hazards of the type of scaffold
  theyll be using
• Understanding the procedures to control or
  minimize hazards
• Hazards including electrical, falling off the
  scaffold, and falling objects
• How to erect, maintain and disassemble the fall
  protection and falling object protection systems
• Using the scaffold and handling materials on the
  scaffold
• Maximum intended load and capacity
• Other information as needed

Employees need training so they dont misuse the
scaffold or do things that will cause it to lose
its integrity, such as removing cross bracing so
they can do their work. Training needs to be
specific to the scaffold the workers will be
using. Job-specific issues would include power
line clearances, surface conditions.
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Worker must be retrained when

• You believe an employee lacks the skill or
  understanding to safety erect, use or dismantle a
  scaffold,
• If an employee's work is inadequate,
• If there is a change in any of the following that
  presents new hazards
• Worksite
• Type of scaffold
• Fall protection
• Falling object protection
• Other equipment

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Provide fall protection for

• employees on a scaffold more than 10 feet above a
  lower level by one of these methods
• guardrails, which must be
• Installed along open sides and ends and
• In place before employees use the scaffold
• OR
• personal fall arrest system
• In accordance with WAC 296-155 Part C-1
• Must be attached to the structure or
• a lifeline -- not the scaffold

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Requirements for Guardrails

• Guardrails consist of toprail, midrail and
  falling object protection, such as a toeboard
• The toprail must be between 38 45 high and
  withstand a 200 lb. force
• The midrail must be installed at a height
  approximately midway between the top edge and the
  platform surface and withstand a 150 lb. force
• A toeboard, when used, must be 3 ½ inches tall
  and able to withstand a 50 lb. force

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Guardrails

• X brace can substitute for top rail or mid
  rail but not both.

Cross bracing is acceptable in place of a
midrail when the crossing point of two braces is
between 20 inches and 30 inches above the work
platform. Cross bracing can be used as a top
rail when the crossing point is between 38 inches
and 48 inches above the work platform. The end
points at each upright must be no more than 48
inches apart.
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Examples of lack of fall protection
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Provide a ladder, ramp or direct access

• For platforms more than 2 feet above or below a
  point of access

In the picture on right, the worker is climbing
the scaffold frame, which is in violation of the
rule.
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Power line clearance
Insulated lines All other power lines
50 299 volts 3 feet 50 50k Volts 10 feet
Over 50k Volts, add .4 per KV
Examples of scaffolds too close to power lines
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Footings

• Sound

• Rigid

• Level

• Support the load without settling or displacement

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Unstable Footing Examples
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Platform specifications
Each working level fully planked no more than 1
gaps
Minimum platform and walkway width of 18
Overlap planks between scaffold sections by at
least 12
Extend end over support 6 min (Maximum end
extension 12)
Dont paint planks since they will hide defects
Front edge within 14 of the work
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Example of improper scaffold planking

• Scaffold platforms must be fully planked
• (and this employee needs fall protection)

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Plank cannot extend more than 18 beyond its
support
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Platforms

• Scaffold grade or equivalent
• 1,500 lb-f/in2 (stress grade) construction lumber
• Manufactured planks used according to
  manufacturers recommendations

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Wood Plank Inspection
Damaged wood planks include Rot, "squishy"
feel, or powdery appearance from termite damage
Cupping of 3/8" or more on a 10" wide or 1/2"
or more on 12" wide plank. Crook of more than
5/16, bow of more than 7/16 or twist of more
than ¾ on a 10 long 10 board. Wane of more
than ¼ the width and ¼ the thickness for more
than ¼ the length of the plank. A split that has
a length of 1 ½ times the board width or
more. Knots that are more than 1 ½ diameter if
loose or 2 diameter if tight on a 10 plank. A
notch cut into a plank more than 1/3 the plank
width. Any saw kerf cut across the plank weakens
the plank by the depth of the cut. The problem
may not be noticed if the plank is later laid
with the cut side down.
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Capacity

• 4 times the intended load scaffold weight
• Planks must not deflect more than 1/60 of span
  when loaded

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Example of Overloaded scaffold
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Overlaps

• Angled plank is not on the bottom
• Not fully planked at transition
• No guardrail at transition

On a corner, planks that dont come in at a right
angle to the support must be on the bottom and
then overlapped by the planks that are at a right
angle.
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Example of Unstable Support

• Forklifts and front-end loaders not designed by
  the manufacturer for such use.

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Guying, Tying or Bracing

• If the ratio of height to base is more than 41
• Install guys every 26 above this tie point for
  scaffolds more than 3 wide.
• Install these guys at each end of the scaffold
  and space additional middle guys no more than 30
  apart.
• If you use a cantilevered work platform (outside
  the framework of the scaffold), then you must use
  some type of bracing such as tying or outriggers
  to prevent the scaffold from tipping.

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Other scaffold use rules

• Dont
• move a scaffold when someone is on it.
• work on a scaffold covered with snow or ice.
• work on a scaffold during a storm or high winds.
• use boxes, barrels or a ladder on top of a
  scaffold to increase its height.
• Do clean up debris on platforms before it
  accumulates.

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Unacceptable Scaffold Example

• Shore or lean to
• Also, a competent person must approve the use of
  dissimilar metals
• Intermixed scaffold components must fit together
  without force and not effect the structural
  integrity of the scaffold.

This is an example of a lean-to scaffold. In this
picture, the workers have a shore scaffold on top
of another shore scaffold. Access is unsafe both
from above and below. The only thing holding this
scaffold up is the DUMPSTER!
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• Thank you for taking the time interest to learn
  about safety and health and how to prevent
  injuries and illnesses.