David
E. Baker and Rusty Lee
University of Missouri Extension
Portable
ladders are one of the handiest, simplest tools we use. Because
of their effectiveness, ladders are used by many different
people to perform many different tasks. Although ladders are
very uncomplicated, planning and care are still required to
use them safely. Each year in the U.S., accidents involving
ladders cause an estimated 300 deaths and 130,000 injuries
requiring emergency medical attention.
Ladder
accidents usually are caused by improper selection, care or
use, not by manufacturing defects. Some of the more common hazards
involving ladders, such as instability, electrical shock, and
falls, can be predicted and prevented. Prevention requires proper
planning, correct ladder selection, good work procedures and
adequate ladder maintenance.
Prevention
tips:
- Do
not hand-carry loads on a ladder.
- Do
not try reaching so far that you lose your balance; move
the ladder.
- Non-skid
feet or spurs may prevent a ladder from slipping on a hard,
smooth surface.
- Do
not stand on the ladder's top three rungs.
- A
damaged side rail may cause one side of a ladder to give
way.
- The
base should be spaced 1 foot away for every 4 feet it reaches
up (see Figure 1).
- Ladders
used to reach a walking surface or roof must extend at least
3 feet beyond.
- Extension
ladders need both locks holding to prevent overloading a
rail.
- Step
ladders should be securely spread open. Never use a folding
step ladder in an unfolded position.
- Electrical
shock can occur with metal or wet wooden ladders. Not only
is the shock itself dangerous, but it can cause falls resulting
in injury.
Portable
ladders are designed as "one-man" equipment with the proper
strength to support the worker as well as his tools and materials.
Ladders are constructed under three general classes:
- Type
I Industrial - Heavy-duty with a load capacity not
more than 250 pounds.
- Type
II Commercial - Medium-duty with a load capacity
not more than 225 pounds (suited for painting and similar
tasks).
- Type
III Household - Light-duty with a load capacity of
200 pounds.
LADDER MAINTENANCE
Wood
ladders should be protected with a clear sealer varnish,
shellac, linseed oil or wood preservative. Wood ladders should
not be painted, because the paint could hide defects. Check
carefully for cracks, rot, splinters, broken rungs, loose joints
and bolts and hardware in poor condition.
Aluminum
or steel ladders should be inspected for rough burrs and
sharp edges before use. Inspect closely for loose joints and
bolts, faulty welds and cracks. Make sure the hooks and locks
on extension ladders are in good condition. Replace worn or
frayed ropes on extension ladders at once.
Fiberglass
ladders should have a surface coat of lacquer maintained.
If it is scratched beyond normal wear, it should be lightly
sanded before applying a coat of lacquer.
- When
working on cylindrical objects like poles and columns, the
top rung of portable ladders can be replaced with chain
or rope to reduce rocking.
- Aluminum
ladders are very corrosion-resistant, but exposing them
to fertilizer can cause damage.
- Use
the ladder inspection checklist to remind yourself of what
you should look out for in order to prevent accidents.
- National
Safety Council, Job Made Ladders, Data Sheet No.
1-568-76, 1976.
- National
Safety Council, Accident Prevention Manual for Industrial
Operations, Ninth Edition, 1988.
- Partial
funding for this guide was provided by the University of
Missouri-Columbia/National Institute for Occupational Safety
and Health Cooperative Agricultural Promotions Agreement.
Ladder
Inspection Checklist |
General |
Needs
repair |
O.K. |
Date
repaired |
Loose
steps or rungs (considered loose if they can be moved
at all with the hand)? |
____________ |
___________ |
____________ |
Loose
nails, screws, bolts, or other metal parts? |
____________ |
____________ |
_____________ |
Cracked,
spilt, or broken uprights, braces, or rungs? |
____________ |
____________ |
_____________ |
Slivers
on uprights, rungs, or steps? |
____________ |
____________ |
_____________ |
Damaged
or worn non-slip bases? |
____________ |
____________ |
_____________ |
Step
ladders |
Wobbly
(from side strain)? |
____________ |
____________ |
_____________ |
Loose
or bent hinge spreaders? |
____________ |
____________ |
_____________ |
Stop
on hinge spreaders broken? |
____________ |
____________ |
_____________ |
Loose
hinges? |
____________ |
____________ |
_____________ |
Broken,
split, or worn steps? |
____________ |
____________ |
_____________ |
Extension
ladders |
Loose,
broken, or missing extension locks? |
____________ |
____________ |
_____________ |
Defective
locks that do not seat properly while extended? |
____________ |
____________ |
_____________ |
Worn
or rotted rope? |
____________ |
____________ |
_____________ |
Disclaimer
and Reproduction Information: Information in NASD does not represent
NIOSH policy. Information included in NASD appears by permission
of the author and/or copyright holder. More
NASD Review: 04/2002
This
document is
GO1932
,
published by the University Extension, University of Missouri-Columbia,
Columbia, MO 65211. Publication date: October 1993.
David
E. Baker and Rusty Lee, Department of Agricultural Engineering,
University of Missouri - Columbia, MO 65211.
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