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148. Portable ladder standards
(1) Except as otherwise permitted by this Part, portable ladder design,
construction and use shall meet the requirements of
(a) CSA Standard CAN3-Z11 "Portable Ladders";
(b) ANSI Standard A14.1-1990 "Safety Requirements for Portable Wood
Ladders";
(c) ANSI Standard A14.2-1990 "Safety Requirements for Portable Metal
Ladders"; or
(d) other standard acceptable to the minister.
(2) A manufactured portable ladder shall be
(a) marked for grade and use; and
(b) used in accordance with the manufacturer's instructions.
154. Restrictions on use
1) Except as otherwise permitted by a manufacturer, a worker shall not work
from either the top 2 rungs of a portable single or extension ladder or the
top 2 steps of a stepladder.
2) A ladder shall not be used as a scaffold component or as a horizontal
walkway, ramp or work platform support except where the ladder is part of
a pre-manufactured or engineered system.
3) A worker shall maintain 3 points of contact when using a ladder.
4) A worker may only work from a portable ladder without fall protection
where
(a) the work is a light duty task of short duration at each location;
(b) the worker's centre of gravity is maintained between the ladder
side rails; and
(c) the ladder is not positioned near an edge or floor opening that
would significantly increase the potential fall distance.
Before the JOB consider the following:
Is a STEPLADDER right for the job?
Task
Plan ahead for the tasks you will be doing
Will you need to
Move around while on ladder
Carry items with you
Work for more than 30 mins
User
Is the user fit enough to work at heights.
Are they comfortable working at heights.
Is the Ladder strong enough?
Maximum Static Vertical load
Weight of user & additional weight carried
Duty Rating
Frequency and general condition
A ladder's duty rating tells you its maximum weight capacity.
There are four categories of duty ratings:
Type IA
These ladders have a duty rating of 300 pounds. Type IA ladders are
recommended for extra-heavy-duty industrial use.
Type I
These ladders have a duty rating of 250 pounds. Type I ladders are
manufactured for heavy-duty use.
Type II
These ladders have a duty rating of 225 pounds. Type II ladders are
approved for medium-duty use.
Type III
These ladders have a duty rating of 200 pounds. Type III ladders are
rated for light-duty use.
Type
Wooden
Aluminium
Fiberglass
Advantages
Disadvantages
* Does not conduct electricity
when dry
* Natural insulator against
cold/ heat
* Heavy
* Can dry and split
* Can fail suddenly
* Light
* Strong
* Robust
* Low maintenance
* Conducts electricity
* Conducts heat and cold
* Does not conduct electricity * Heavy
* Can withstand cold and heat * Chip or crack under impact
* Can crack or fail under heavy
load
1) User Inspections
- Stiles
- Platform
- Non-slip feet
- Locking devices
- Steps or Treads
- ID tag – readable?
2) People and Place safety
- Not for work more than 30 minutes in duration
- Not for work requiring more than 10kg weight to be lifted
- Footwear – CSA safety
- Clothing - proper fitting clothing
- Check area – overhead, other people, firm base,
doors , safe “drop zone”
3) Ladder set up
- Is it fully opened and locked into correct position
- Is it on firm and level base
- Is it positioned with steps facing work
- Multi design ladders must be set up properly for work being
preformed
4) User guidelines
- Secure grip at all times
- 3 point contact when climbing
- Ensure all items are secure on ladder
- Do not use top platform as work step
- MOVE LADDER FOR WORK AND DO NOT OVER REACH
NL Regs section 153 Extension Ladder Length.
A ladder shall be of sufficient length to project
approximately one metre above the level of the
upper landing to which it provides access, except
where there is limited clearance and the ladder is
adequately secured.
What should you do to safely secure extension ladders?
• Place ladders on a firm, level surface and ensure the footing is
secure.
• Erect extension ladders so that the upper section rests on (e.g.,
in front of) the bottom section. This means the bottom section
"faces" a wall or other supporting surface (see figures below).
• Place the ladder feet so that the horizontal distance between
the feet and the top support is 1/4 of the working length of the
ladder. The ladder will be leaning at a 75 degree angle from the
ground.
• Raise and lower ladders from the ground. Ensure that locking
ladder hooks are secure before climbing.
• Erect ladders so that a minimum of 1 m (3 ft) extends above a
landing platform. Tie the top at support points.
• Brace or tie off the ladder near the base. If there is no structure
to tie off to, use a stake in the ground.
• Leave all tie-off devices in place until they must be removed
before taking the ladder down.
• Maintain the minimum overlap of sections as shown on a ladder
label. Refer to safety regulations.
Note: When working 3 metres (10 feet) or more above ground,
wear a safety belt or harness with the lanyard tied appropriately
to the structure.
What should you avoid when using extension ladders?
•
•
•
•
•
•
•
Do not use ladders near electrical wire.
Do not set up or take a ladder down when
it is extended.
Do not overextend. Maintain minimum overlap
of sections.
Do not climb higher than the fourth rung from the
top of a ladder.
Do not use ladders on ice, snow or other slippery surfaces
without securing ladders' feet.
Do not extend top section of a ladder from above or by
"bouncing" on a ladder.
Do not leave ladders unattended.
What should you do to avoid overexertion while setting up an extension
ladder?
When setting up an extension ladder, use the following method to avoid
straining muscles or losing control of a ladder. With ladders weighing more
than 25 kg (55 lb), or where conditions complicate the task, have two
persons set up a ladder, step by step, as follows:
Lay a ladder on the ground close to intended location.
Brace ladder base using helpers' feet.
Grasp the top rung with both hands, raise the top end over your head and
walk toward the base of a ladder. Grasp the centre of the rungs to maintain
stability.
Move the erect ladder to the desired location. Lean it
forward against the resting point.
One person can erect a short ladder, step by step as follows:
Place the bottom of a ladder firmly against the base of a
building or stationary object.
Lift the top of ladder, and pull upwards to raise a ladder to a
vertical position.
Transfer a ladder to its required position when it is erect.
Keep a ladder upright and close to the body with a firm grip.
Scaffold erection and dismantling must be done by, or supervised by,
qualified workers.
The vertical supports of scaffolds must be Placed on a firm base or sill
Capable of withstanding superimposed weight from the scaffold and
anything placed on the scaffold
Do not use pallets, boxes, concrete blocks, bricks, or other unstable
materials to support scaffolds.
All scaffolds must be erected plumb and level, and be designed for the
intended use.
Scaffolds must be secured to the building structure approximately 4.6 m (15
ft.) vertically but not to exceed 6.1 m (20 ft.) vertically and 6.4 m (21 ft.)
horizontally. NOTE: Narrow scaffolds must be secured to the structure when
the platform height exceeds three times the smallest base dimension.
Bracing requirements for prefabricated scaffolds must be installed
according to the manufacturer’s instructions. Bracing for job-built
scaffolding must meet standards acceptable to OHS.
All scaffolds must be inspected before use by those who will use them,
regardless of who erected them. No damaged or weakened scaffold may be
used until it has been effectively repaired.
Aerial Lift
Suspended
“Pump Jack”
Supported
“Framed or Fabricated”
Falls from scaffolds are one of the leading causes of injuries to construction
workers .
All scaffolds 3 m (10 ft.) or more above grade must have standard guardrails
on their open side.
A standard guard consists of:
A top rail approximately 1.1 m (42 in.) above the platform
An intermediate rail centred at approximately the midpoint of the
space between the underside of the top rail and the upper edge of the
platform
Vertical guardrail supports spaced not more than 3 m (10 ft.) apart for
wooden scaffolding
Standard guardrails must be designed to withstand a static load of 550
N (125 lb.) applied laterally at any point of the top rail.
1.1 m
(42")
Top rail
2" x 4"
or 2" x 6“
Intermediate
rail 2" x 4"
Maximum 3 m (10 ft.) between supports
Manufactured scaffold planks are available in various lengths and duty ranges.
These planks must be installed and used according to the manufacturer’s and/or
supplier’s specifications. Securing devices for aluminum/plywood platforms
Examples of the various types of manufactured plank and securing devices
for aluminum/plywood platforms
General requirements
Wood scaffolding must be built using No. 2 or better lumber. To
eliminate split, warped, or otherwise defective lumber, scaffold
materials should be hand-selected.
Progressively brace the scaffold as it is erected.
Make sure there is firm contact between bearer blocks,
bearers, wall scabs, and ledgers to provide maximum strength
at connecting points.
The number and size of nails and nailing patterns at
connections should be consistent with good practice. As a
guide, nails should protrude at least two-thirds of the thickness
into the adjoining piece of lumber.
When holding power is critical, or when the scaffold will be
used for an extended length of time, dip galvanized or
spiral nails should be used. When scaffold components are
intended to be dismantled and reused, double-headed
nails may be used.
Caution: Do not use the same nail holes on reassembly.
Do not exceed the maximum allowable dimensions for
bearers and upright spacing.
Do not overload the scaffold.
The spacing of vertical supports (uprights) and bearers
must not exceed 3 m (10 ft.).
2" x 4" or 2" x 6” Top rail
2" x 4“ Intermediate rail
2” x 10” Platform
2" x 4" or 1" x 6“ Ledger
1" x 6" or 2" x 4" Brace
Mudsill
Maximum 3m (10ft) between supports)
Note: For sake of drawing clarity,
toeboards are not shown.
All scaffold planks must be inspected and tested before use.
Lumber or manufactured scaffold planks used for a work
platform must consist of at least two planks placed side by side
to provide a work surface with a nominal width of 50 cm (20 in.),
or nominal width of 30 cm (12 in.) for ladder-jack platforms.
Scaffold planks should completely cover the area between front
and rear vertical supports or the rear guardrail.
Scaffold planks must be secured against any movement in any
direction (including uplift).
Sawn wood planks must be hand-selected and in the following
grades and sizes:
Minimum width
mm
inches
Select Structural — Scaffold Planks
38 x 235
2 x 10 nominal
Select Structural — Joists & Planks
48 x 251
2 x 10 nominal
No. 2 and Better — Joists & Planks*
38 x 235
2 x 10 rough sawn
No. 2 and Better — Joists & Planks
38 x 235
2 x 10 dressed/nominal
* Important: These planks must be doubled, one on top of the other.
Using the specifications above, the maximum span is:
3 m (10 ft.) for light-duty scaffolds
2.1 m (7 ft.) for heavy-duty scaffolds
Lumber used for planks must be graded and marked to the
National Lumber Grades Authority (NLGA) Standard Grading
Rules for Canadian Lumber.
Scaffold planks must extend a minimum of 150 mm (6 in.) and
a maximum of 300 mm (12 in.) beyond their supports.
Scaffold planks must be held in place if there is a danger of the
planks slipping off their supports.
Manufacturer’s specifications must be followed for testing
laminated wood scaffold planks. The following is an acceptable
method for testing sawn wood scaffold planks:
Place test scaffold plank on two blocks. The block size and test
span must be selected from the following table:
Test Span Span
Block Size
2.1 m (7 ft.)
60 mm (23⁄8 in.)
3 m (10 ft.)
92 mm (35⁄8 in.)
Have two workers who together weigh at least 148 kg (325 lb.)
stand on the centre of the supported plank. Do not jump up
and down on the plank.
Reject the plank if any of the following events occur:
The plank bends enough to contact the ground
Cracking sounds are heard (indicating fibre overstressing)
After removal of the test load, the plank fails to return to
its original position (i.e., it remains bent)
Scaffold planks passing this test should be identified by
stencilling or end painting. It is also advisable to have the ends
of the planks encased in metal sleeves or jackets for damage
protection and additional identification.
To prevent damage, scaffold planks must be handled carefully,
used correctly, and stored properly.
Scaffold planks must never be overloaded, used as sills, or
subjected to any condition that could affect the integrity of
the plank as a working platform.
Single-pole wood scaffold for light
duty
2" x 4"
Upright
Metal bearer bar
2" x 6" Bearer
The spacing of vertical supports and
bearers of a single-pole wood
scaffold for light duty must not
exceed 3 m (10 ft.).
On single-pole scaffolds, the inner
ends of bearers must be supported
by bearer blocks securely fastened to
wall scabs
2" x 6"
Wall scab
2" x 4"
Bearer
block
Minimum
610 mm
(2 ft.)
overlap
Pump jack scaffolds must be erected, operated, and
maintained in accordance with the manufacturer’s instructions.
A copy of the manufacturer’s instructions must be readily
available on site for reference by workers.
No more than two workers are permitted on a pump jack
scaffold at one time. The maximum allowable safe working
load is 227 kilograms (500 pounds).
Each pump jack bracket must have two positive gripping
mechanisms to prevent failure or slippage.
Wood poles shall
Not be spaced more than 2.3 metres (seven feet) apart
Be secured to the work wall by rigid triangular bracing at the
top, bottom, and other points such that the maximum distance
between braces is three metres (10 feet)
Not exceed nine metres (30 feet) in height
Require mending plates installed at all splices, when two by
fours are spliced to make a pole
Have the seam parallel to the bracket when constructed of two
continuous lengths joined together
Metal poles shall :
Be secured as specified by the manufacturer’s instructions
Have a minimum of one brace up to 7.3 metres (24 feet), and
above that height the bracing shall not exceed a maximum
span of 4.9 metres (16 feet) from top to bottom
Not exceed 15.2 metres (50 feet) in height unless certified by an
engineer
Poles must be placed on mud-sills or other adequate firm
foundation.
The work platform must be
Secured to the pump jack brackets
A minimum width of 30 centimetres (12 inches)
A bench platform, incorporated in the scaffold at an
approximate height of 107 cm (42 in.), is acceptable in lieu of a
top rail.
Here are the safety violations they spotted:
The access ladder is too short (it must be long enough to project
approximately 1 m (3 ft.) above the upper landing to which it
provides access).
The scaffold has a lockout tag placed on it, indicating the scaffold
is unfinished and should not be used.
There is a bucket near the edge. If excess material could fall off
the scaffold, a toe board should be used.
The worker doesn’t have safe access to the scaffold, and would
have to climb through the guardrails to access the upper
platform.
The worker doesn’t have safe access to the lower level of the
scaffold, and would have to crawl through the brace to reach it.
There is a dangerous gap in the middle of the upper level
platform — a slip/trip hazard.
The lower level platform is unfinished. The worker needs a
guardrail to use it.
The cross brace is missing from the back of the scaffold (it must
be erected according to the manufacturer’s instructions).
The mid-rail is missing on the upper platform, a key component
of a guardrail system.
Firm Foundation
To ensure stability, scaffold must
be placed on Base plates
Mud Sills
Or other adequate firm foundation
Capacity. Scaffolds must be capable
of supporting their own weight and
at least 4 times their maximum
intended load
Bracing. Frames must be connected by cross, horizontal or
diagonal braces, alone or in combination, which secure vertical
members together laterally.
Fall Protection
Consists of either “fall arrest” – harness and lifeline, or “fall
prevention” – guardrails
Must be in place when worker is at height greater than 3.05 m
(10ft) or more at workers feet level
All employees working at this level must wear fall arrest
equipment
Fall arrest:
Can not be tied off to standpipes, electrical conduit, vents or
the like
Guardrails
Must be on all platforms over 4ft from ground or previous level
of scaffold
Must have vertical supports no more than 8ft apart
Must not be no more than 1.07 m ( 3.51ft) from floor with a rail
in between the two.
Maybe be replaced by cross braces as long as intersection of
brace is between 50.8-76.2 (20-30inches) for mid guardrail and
96.5-122cm (38-48) inches for toprail.
Working Gap
There can be no more than 14 inches between the scaffold and
the structure worked on.
Falling Object Protection
All persons working around scaffolding must be protected
against falling objects/debris by hard hat, toeboards, screens or
netting.
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