Figure 1:
Scaffolding used to access rudder. |
Scaffolds, or staging, are devices used to provide an elevated
working surface. Staging may be various designs and is often constructed to fit the ship.
Staging must be
adequate for the work performed because falls are a significant hazard in
the shipyard.
Before working on or near any scaffolding, workers should ensure that scaffolds
are:
- Safely secured and supported,
- Level,
- Provided with safe access (such as ladders),
- Adequately decked (for example, have a work surface and platform), and
- Provided with guard rails (hand and mid).
The following are general requirements for all staging and scaffolds:
Types of Scaffolding (Staging):
Note: The terms scaffold and staging are used interchangeably.
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Note: Confined space entry is one of the leading
hazards associated with barge cleaning. Review the
Shipbreaking: Confined/Enclosed
Spaces and Other Dangerous Atmospheres
chapter for information on how to protect workers from this hazard.
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General
Scaffolding Requirements
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Scaffolding, or staging, presents hazards for personnel
working from, accessing, or leaving a scaffold. To be
safe, scaffolding must be constructed from specified
materials in an approved manner. [1915.71(b)] Fall
protection must be provided for the workers on the scaffold. [1915.71(j)(1)]
Protection from falling objects must be provided for workers below the
scaffold. [1915.71(j)(5)]
Potential Hazards:
- Failure or overloading of the staging components may result in the collapse of the unit in
whole or in part, causing workers to fall.
- Surging when working on scaffolds mounted on floating vessels (for example, movement of work surface). See
Figure 3.
- Workers on the scaffolds falling to the level below.
- Items falling from the scaffolds and striking workers below.
Requirements and Example Solutions:
- All scaffolds and their supports must be capable of supporting the
load they are designed to carry with a safety factor of no less than
four. [1915.71(b)(1)]
- All lumber (such as scaffold grade, ([1915.71(b)(2) and
(b)(3)]) used in the construction of scaffolds
must be sound, straight, and free from defects. [1915.71(b)(4)]
- Note: Laminated planking providing the equivalent strength of
scaffold-grade planking is acceptable if it is substantiated by
engineering data. See the following OSHA Standard Interpretation Letters:
- Scaffolds shall be maintained in a safe and secure condition. Any component of the scaffold
that is broken, burned, or otherwise
defective must be replaced. [1915.71(b)(5)]
- Unstable objects (such as barrels, boxes, cans, or loose bricks) must not be used as working platforms, or
to support working platforms. [1915.71(b)(6)]
- Scaffolds must be erected, moved, dismantled, or altered under the supervision of
scaffold competent persons. [1915.71(b)(7)] Note: This is not the
Shipyard Competent Person (SCP).
Scaffold or Platform Planking
- Platform planking shall be of not less than 2 x 10-inch
lumber. [1915.71(i)(1)]
- Platforms of staging shall not be less than two 10-inch planks in
width except in such cases as the structure of the vessel or the width
of the trestle ladders make it impossible to provide such a width. [1915.71(i)(2)]
- Platform planking shall project beyond the supporting members at
either end by at least 6 inches but in no case shall project more than
12 inches unless the planks are fastened to the supporting members. [1915.71(i)(3)]
- Scaffold planks shall not be overloaded. [1915.71(i)(4)]
- Note: Laminated planking providing the equivalent strength of
scaffold grade planking is acceptable if it is substantiated by
engineering data. See the following OSHA Standard Interpretation Letters:
Guardrails and Toeboards
- Scaffolding more than 5 feet above a solid surface, or at
any distance above the water, must be provided with railing that has: [1915.71(j)(1)]
- A top rail of 42 to 45 inches high.
- A midrail
located halfway between the top rail and the platform.
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Figure 2: Unstable scaffolding and missing guardrails.
Figure 3: Scaffold without guardrails subject to surging motion.
Figure 4: Properly erected and
guarded pole scaffolding.
Figure 5: Unsafe scaffold and ramp access, supported by unstable stand.
Figure 6: Scaffold planking extending more than 12 inches beyond supports and no guardrails provided. |
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Rails must be of 2 x 4-inch lumber, flat bar, or
pipe. [1915.71(j)(2)]
- When used with rigid supports, taut wire or fiber rope of
adequate strength may be used.
- If the distance between supports is
more than 8 feet, rails must be equivalent in strength to 2 x 4-inch
lumber.
- Rails must be firmly secured.
- Where exposed to hot work or
chemicals, fiber rope rails must not be used.
- Note: Chains or other material may be used as guardrails provided they meet the requirements of 1915.71(j)(1).
- Rails may be omitted where the structure of the
vessel prevents their use. [1915.71(j)(3)]
- When rails are omitted, employees working
more than 5 feet above solid surfaces must be protected by safety
belts (harnesses) and life lines meeting the requirements of 1915.159(b).
- Employees working over water must be protected by buoyant work vests
meeting the requirements of 1915.158(a).
- Employees must be protected against falling toward the vessel
while working on a swinging or floating scaffold. [1915.71(j)(4)]
- When necessary, to prevent tools and materials from
falling on workers below, toeboards of not less than 1 x 4-inch lumber
must be provided. [1915.71(j)(5)]
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Access to Staging
- Staging more than 5 feet high requires appropriate access (ladders, ramps, and stairways). [1915.71(k)(1)]
- Ramps and stairways must be provided with 36-inch handrails with
midrails. [1915.71(k)(2)]
- Ladders must be located so employees do not need to step more than 1 foot from the ladder to any intermediate landing or platform. [1915.71(k)(3)]
- Staging with built-in ladders meets these requirements. [1915.71(k)(4)]
- Staging more than 3 feet below the point of access requires
straight, portable, or Jacob's ladder. [1915.71(k)(5)]
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Figure 7: Mobile scaffold (stair tower) with proper access to working surfaces.
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Maritime Labor/Industry Recommendation
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- Live-load and live-boom cranes, such as free falls, should not be
used.
- Employees being hoisted should remain in
continuous sight of or in direct communication with (radio) the operator or signal person.
- Except over water, employees occupying the
personnel platform should use a body belt/harness system with
lanyard properly attached and capable of supporting a fall impact
for employees using the anchorage. While working over water workers should
wear a personal flotation device (PFD).
- An anti-two-block device should be used.
- Personnel platform and suspension systems, such as guard rails, bridles,
safe working load, and so forth, should be designed by a qualified engineer
or a qualified person competent in structural design and maximum
intended load should not be exceeded.
- A visual inspection of the crane or derrick, rigging, personnel
platform, and the crane or derrick base support or ground should be
conducted by a competent person. Note: This is not the Shipyard
Competent Person (SCP).
- Employees should keep all body parts inside the platform
during raising, lowering, and positioning.
- Tag lines should be used unless their use creates an unsafe
condition.
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Figure 8: Personnel platform being used without following best practices such as using anti-two
block device and personal fall protection.
Figure 9: Man basket used without tag line or personal fall protection, and with an improperly
guarded open side. |
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