R 408.41124
R 408.41124 Portable ladders.
Cite as Mich. Admin. Code R 408.41124
Rule 1124. (1) A portable ladder must be used at such a pitch that the horizontal
projected distance from the top support to the base is not more than 1/4 of the vertical
distance between these points.
(2) A portable ladder in use shall be equipped with appropriate safety feet, unless the
ladder is tied, blocked, or otherwise secured to prevent it from being displaced.
Slip-resistant feet must not be used as a substitute for care in placing, lashing, or holding
a ladder that is used upon slippery surfaces, including flat metal or concrete surfaces that
are constructed so that they cannot be prevented from becoming slippery.
(3) A portable ladder that is used at such a pitch that the horizontal projected
distance from the top support to the base is less than 1/5 of the vertical distance between
these points shall be secured at the top to prevent tipping backward.
(4) A portable ladder that is used at a pitch of 80 degrees or more shall be in
compliance with the requirements of a fixed ladder as prescribed in General Industry
Safety and Health Standard Part 2. “Walking-Working Surfaces,” as referenced in
R 408.41102a.
(5) When portable ladders are used for access to an upper landing surface, the ladder
side rails must extend not less than 3 feet (0.9 m) above the upper landing surface to
which the ladder is used to gain access; or, when such an extension is not possible
because of the ladder’s length, then the ladder must be secured at its top to rigid support
that will not deflect and a grasping device, such as a grab-rail, shall be provided to assist
employees in mounting and dismounting the ladder. The side rails shall not extend in a
manner that would permit ladder deflection under a load, by itself, to cause the ladder to
slip off its support. The top of a non-self-supporting ladder shall be placed with the 2 rails
supported equally, unless the ladder is equipped with a single support attachment.
(6) A manufactured portable metal ladder shall not be used for electrical work or
where the ladder or an employee may contact electrical conductors.
A ladder shall have nonconductive side-rails if the ladder is used where the employee
or the ladder could contact exposed energized electrical equipment, except as provided in
Construction Safety Standard Part 16. “Power Transmission and Distribution,” as
referenced in R 408.41102a.
(7) A metal ladder must not be used or moved unless a minimum of 20 feet is
maintained between power transmission or distribution lines.
(8) A power transmission or distribution line or electrical apparatus must be
considered energized unless the property owner or utility indicates it is de-energized and
the line or apparatus is visibly grounded. Where de-energizing is impractical, the
minimum clearances set forth in table 1 shall be maintained between the ladder,
employee, or material, whichever is closer.
(9) Table 1 reads as follows:
TABLE 1
VOLTAGE
MINIMUM CLEARANCE
To 50 kV
10 feet
Over 50 kV
10 feet plus .4 inch per kV
(10) An employee who is using a portable ladder shall not stand on the top 2 rungs
or within 3 feet of the top of the ladder.
(11) Two portable ladders must not be spliced together to provide long sections
unless such ladders are specifically designed for such use.
(12) A portable 2-section extension ladder must be erected so that the top section
rests on the base section. The top section must be the section nearest to the climber.
(13) A non-self-supporting ladder must be used at an angle such that the horizontal
distance from the top support to the foot of the ladder is approximately 1/4 of the working
length of the ladder that is the distance along the ladder between the foot and the top
support.
(14) A fixed ladder must be used at a pitch of not more than 90 degrees from the
horizontal, as measured to the back side of the ladder.
(15) An employer shall ensure that each self-supporting portable ladder complies
with all of the following:
(a) A ladder must sustain at least 4 times the maximum intended load, except that
each extra-heavy-duty type 1A metal or plastic ladder must sustain at least 3.3 times the
maximum intended load.
(b) The ability of a ladder to sustain the loads indicated in this rule is determined by
applying or transmitting the requisite load to the ladder in a downward vertical direction.
(c) Ladders built and tested in conformance with the applicable provisions of
R 408.41111, are deemed to meet this requirement.
See figure 5.