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OSHA
Regulations (Standards - 29 CFR) - Table of Contents OSHA Regulations
(Standards - 29 CFR) - Table of Contents
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Standard Number: 1926 Subpart M App C
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Standard Title: Personal Fall Arrest Systems - Non-Mandatory
Guidelines for Complying with 1926.502(d)
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SubPart Number: M
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SubPart Title: Fall Protection
I.
Test methods for personal fall arrest systems and positioning
device systems -
(a)
"General." This appendix serves as a non-mandatory
guideline to assist employers comply with the requirements in
1926.502(d). Paragraphs (b), (c), (d) and (e) of this Appendix
describe test procedures which may be used to determine compliance
with the requirements in 1926.502 (d)(16). As noted in Appendix
D of this subpart, the test methods listed here in Appendix
C can also be used to assist employers comply with the requirements
in 1926.502(e) (3) and (4) for positioning device systems.
(b)
"General conditions for all tests in the Appendix to 1926.502(d)."
(1)
Lifelines, lanyards and deceleration devices should be attached
to an anchorage and connected to the body-belt or body harness
in the same manner as they would be when used to protect employees.
(2)
The anchorage should be rigid, and should not have a deflection
greater than 0.04 inches (1 mm) when a force of 2,250 pounds
(10 kN) is applied.
(3)
The frequency response of the load measuring instrumentation
should be 500 Hz.
(4)
The test weight used in the strength and force tests should
be a rigid, metal, cylindrical or torso-shaped object with a
girth of 38 inches plus or minus 4 inches (96 cm plus or minus
10 cm).
(5)
The lanyard or lifeline used to create the free fall distance
should be supplied with the system, or in its absence, the least
elastic lanyard or lifeline available to be used with the system.
(6)
The test weight for each test should be hoisted to the required
level and should be quickly released without having any appreciable
motion imparted to it.
(7)
The system's performance should be evaluated taking into account
the range of environmental conditions for which it is designed
to be used. (8) Following the test, the system need not be capable
of further operation.
(c)
"Strength test." (1) During the testing of all systems,
a test weight of 300 pounds plus or minus 5 pounds (135 kg plus
or minus 2.5 kg) should be used. (See paragraph (b)(4) of this
section.)
(2)
The test consists of dropping the test weight once. A new unused
system should be used for each test.
(3)
For lanyard systems, the lanyard length should be 6 feet plus
or minus 2 inches (1.83 m plus or minus 5 cm) as measured from
the fixed anchorage to the attachment on the body belt or body
harness.
(4)
For rope-grab-type deceleration systems, the length of the lifeline
above the centerline of the grabbing mechanism to the lifeline's
anchorage point should not exceed 2 feet (0.61 m).
(5)
For lanyard systems, for systems with deceleration devices which
do not automatically limit free fall distance to 2 feet (0.61
m ) or less, and for systems with deceleration devices which
have a connection distance in excess of 1 foot (0.3 m) (measured
between the centerline of the lifeline and the attachment point
to the body belt or harness), the test weight should be rigged
to free fall a distance of 7.5 feet (2.3 m) from a point that
is 1.5 feet (.46 m) above the anchorage point, to its hanging
location (6 feet below the anchorage). The test weight should
fall without interference, obstruction, or hitting the floor
or ground during the test. In some cases a non-elastic wire
lanyard of sufficient length may need to be added to the system
(for test purposes) to create the necessary free fall distance.
(6)
For deceleration device systems with integral lifelines or lanyards
which automatically limit free fall distance to 2 feet (0.61
m) or less, the test weight should be rigged to free fall a
distance of 4 feet (1.22 m).
(7)
Any weight which detaches from the belt or harness has failed
the strength test.
(d)
"Force test" - (1) "General." The test consists
of dropping the respective test weight once as specified in
paragraph (d)(2)(i) or (d)(3)(i) of this section. A new, unused
system should be used for each test.
(2)
"For lanyard systems." (i) A test weight of 220 pounds
plus or minus 3 pounds (100 kg plus or minus 1.6 kg) should
be used. (See paragraph (b)(4) of this appendix).
(ii)
Lanyard length should be 6 feet plus or minus two inches (1.83
m plus or minus 5 cm) as measured from the fixed anchorage to
the attachment on the body belt or body harness.
(iii)
The test weight should fall free from the anchorage level to
its hanging location (a total of 6 feet (1.83 m) free fall distance)
without interference, obstruction, or hitting the floor or ground
during the test.
(3)
"For all other systems." (i) A test weight of 220
pounds plus or minus 3 pounds (100 kg plus or minus 1.6 kg)
should be used. (See paragraph (b)(4) of this appendix)
(ii)
The free fall distance to be used in the test should be the
maximum fall distance physically permitted by the system during
normal use conditions, up to a maximum free fall distance for
the test weight of 6 feet (1.83 m), except as follows:
(A)
For deceleration systems which have a connection link or lanyard,
the test weight should free fall a distance equal to the connection
distance (measured between the centerline of the lifeline and
the attachment point to the body belt or harness).
(B)
For deceleration device systems with integral lifelines or lanyards
which automatically limit free fall distance to 2 feet (0.61
m) or less, the test weight should free fall a distance equal
to that permitted by the system in normal use. (For example,
to test a system with a self-retracting lifeline or lanyard,
the test weight should be supported and the system allowed to
retract the lifeline or lanyard as it would in normal use. The
test weight would then be released and the force and deceleration
distance measured).
(4)
A system fails the force test if the recorded maximum arresting
force exceeds 1,260 pounds (5.6 kN) when using a body belt,
and/or exceeds 2,520 pounds (11.2 kN) when using a body harness.
(5)
The maximum elongation and deceleration distance should be recorded
during the force test.
(e)
"Deceleration device tests." (1) "General."
The device should be evaluated or tested under the environmental
conditions, (such as rain, ice, grease, dirt, type of lifeline,
etc.), for which the device is designed.
(2)
"Rope-grab-type deceleration devices." (i) Devices
should be moved on a lifeline 1,000 times over the same length
of line a distance of not less than 1 foot (30.5 cm), and the
mechanism should lock each time.
(ii)
Unless the device is permanently marked to indicate the type(s)
of lifeline which must be used, several types (different diameters
and different materials), of lifelines should be used to test
the device.
(3)
"Other self-activating-type deceleration devices."
The locking mechanisms of other self-activating-type deceleration
devices designed for more than one arrest should lock each of
1,000 times as they would in normal service.
II.
Additional non-mandatory guidelines for personal fall arrest
systems. The following information constitutes additional guidelines
for use in complying with requirements for a personal fall arrest
system.
(a)
"Selection and use considerations." (1) The kind of
personal fall arrest system selected should match the particular
work situation, and any possible free fall distance should be
kept to a minimum. Consideration should be given to the particular
work environment. For example, the presence of acids, dirt,
moisture, oil, grease, etc., and their effect on the system,
should be evaluated. Hot or cold environments may also have
an adverse effect on the system. Wire rope should not be used
where an electrical hazard is anticipated. As required by the
standard, the employer must plan to have means available to
promptly rescue an employee should a fall occur, since the suspended
employee may not be able to reach a work level independently.
(2)
Where lanyards, connectors, and lifelines are subject to damage
by work operations such as welding, chemical cleaning, and sandblasting,
the component should be protected, or other securing systems
should be used. The employer should fully evaluate the work
conditions and environment (including seasonal weather changes)
before selecting the appropriate personal fall protection system.
Once in use, the system's effectiveness should be monitored.
In some cases, a program for cleaning and maintenance of the
system may be necessary.
(b)
"Testing considerations." Before purchasing or putting
into use a personal fall arrest system, an employer should obtain
from the supplier information about the system based on its
performance during testing so that the employer can know if
the system meets this standard. Testing should be done using
recognized test methods. This Appendix contains test methods
recognized for evaluating the performance of fall arrest systems.
Not all systems may need to be individually tested; the performance
of some systems may be based on data and calculations derived
from testing of similar systems, provided that enough information
is available to demonstrate similarity of function and design.
(c)
"Component compatibility considerations." Ideally,
a personal fall arrest system is designed, tested, and supplied
as a complete system. However, it is common practice for lanyards,
connectors, lifelines, deceleration devices, body belts and
body harnesses to be interchanged since some components wear
out before others. The employer and employee should realize
that not all components are interchangeable. For instance, a
lanyard should not be connected between a body belt (or harness)
and a deceleration device of the self-retracting type since
this can result in additional free fall for which the system
was not designed. Any substitution or change to a personal fall
arrest system should be fully evaluated or tested by a competent
person to determine that it meets the standard, before the modified
system is put in use.
(d)
"Employee training considerations." Thorough employee
training in the selection and use of personal fall arrest systems
is imperative. Employees must be trained in the safe use of
the system. This should include the following: application limits;
proper anchoring and tie-off techniques; estimation of free
fall distance, including determination of deceleration distance,
and total fall distance to prevent striking a lower level; methods
of use; and inspection and storage of the system. Careless or
improper use of the equipment can result in serious injury or
death. Employers and employees should become familiar with the
material in this Appendix, as well as manufacturer's recommendations,
before a system is used. Of uppermost importance is the reduction
in strength caused by certain tie-offs (such as using knots,
tying around sharp edges, etc.) and maximum permitted free fall
distance. Also, to be stressed are the importance of inspections
prior to use, the limitations of the equipment, and unique conditions
at the worksite which may be important in determining the type
of system to use.
(e)
"Instruction considerations." Employers should obtain
comprehensive instructions from the supplier as to the system's
proper use and application, including, where applicable:
(1)
The force measured during the sample force test;
(2) The maximum elongation measured for lanyards during the
force test;
(3) The deceleration distance measured for deceleration devices
during the force test;
(4) Caution statements on critical use limitations;
(5) Application limits;
(6) Proper hook-up, anchoring and tie-off techniques, including
the proper dee-ring
or other attachment point to use on the body
belt and harness for fall arrest;
(7) Proper climbing techniques;
(8) Methods of inspection, use, cleaning, and storage; and
(9) Specific lifelines which may be used.
This
information should be provided to employees during training.
(f)
"Rescue considerations." As required by 1926.502(d)(20),
when personal fall arrest systems are used, the employer must
assure that employees can be promptly rescued or can rescue
themselves should a fall occur. The availability of rescue personnel,
ladders or other rescue equipment should be evaluated. In some
situations, equipment which allows employees to rescue themselves
after the fall has been arrested may be desirable, such as devices
which have descent capability.
(g)
"Inspection considerations." As required by 1926.502(d)(21),
personal fall arrest systems must be regularly inspected. Any
component with any significant defect, such as cuts, tears,
abrasions, mold, or undue stretching; alterations or additions
which might affect its efficiency; damage due to deterioration;
contact with fire, acids, or other corrosives; distorted hooks
or faulty hook springs; tongues unfitted to the shoulder of
buckles; loose or damaged mountings; non-functioning parts;
or wearing or internal deterioration in the ropes must be withdrawn
from service immediately, and should be tagged or marked as
unusable, or destroyed.
(h)
"Tie-off considerations." (1) One of the most important
aspects of personal fall protection systems is fully planning
the system before it is put into use. Probably the most overlooked
component is planning for suitable anchorage points. Such planning
should ideally be done before the structure or building is constructed
so that anchorage points can be incorporated during construction
for use later for window cleaning or other building maintenance.
If properly planned, these anchorage points may be used during
construction, as well as afterwards.
(i)
Properly planned anchorages should be used if they are available.
In some cases, anchorages must be installed immediately prior
to use. In such cases, a registered professional engineer with
experience in designing fall protection systems, or another
qualified person with appropriate education and experience should
design an anchor point to be installed.
(ii)
In other cases, the Agency recognizes that there will be a need
to devise an anchor point from existing structures. Examples
of what might be appropriate anchor points are steel members
or I-beams if an acceptable strap is available for the connection
(do not use a lanyard with a snaphook clipped onto itself);
large eye-bolts made of an appropriate grade steel; guardrails
or railings if they have been designed for use as an anchor
point; or masonry or wood members only if the attachment point
is substantial and precautions have been taken to assure that
bolts or other connectors will not pull through. A qualified
person should be used to evaluate the suitable of these "make
shift" anchorages with a focus on proper strength.
(2)
Employers and employees should at all times be aware that the
strength of a personal fall arrest system is based on its being
attached to an anchoring system which does not reduce the strength
of the system (such as a properly dimensioned eye-bolt/snap-hook
anchorage). Therefore, if a means of attachment is used that
will reduce the strength of the system, that component should
be replaced by a stronger one, but one that will also maintain
the appropriate maximum arrest force characteristics.
(3)
Tie-off using a knot in a rope lanyard or lifeline (at any location)
can reduce the lifeline or lanyard strength by 50 percent or
more. Therefore, a stronger lanyard or lifeline should be used
to compensate for the weakening effect of the knot, or the lanyard
length should be reduced (or the tie-off location raised) to
minimize free fall distance, or the lanyard or lifeline should
be replaced by one which has an appropriately incorporated connector
to eliminate the need for a knot.
(4)
Tie-off of a rope lanyard or lifeline around an "H"
or "I" beam or similar support can reduce its strength
as much as 70 percent due to the cutting action of the beam
edges. Therefore, use should be made of a webbing lanyard or
wire core lifeline around the beam; or the lanyard or lifeline
should be protected from the edge; or free fall distance should
be greatly minimized.
(5)
Tie-off where the line passes over or around rough or sharp
surfaces reduces strength drastically. Such a tie-off should
be avoided or an alternative tie-off rigging should be used.
Such alternatives may include use of a snap-hook/dee ring connection,
wire rope tie-off, an effective padding of the surfaces, or
an abrasion-resistance strap around or over the problem surface.
(6)
Horizontal lifelines may, depending on their geometry and angle
of sag, be subjected to greater loads than the impact load imposed
by an attached component. When the angle of horizontal lifeline
sag is less than 30 degrees, the impact force imparted to the
lifeline by an attached lanyard is greatly amplified. For example,
with a sag angle of 15 degrees, the force amplification is about
2:1 and at 5 degrees sag, it is about 6:1. Depending on the
angle of sag, and the line's elasticity, the strength of the
horizontal lifeline and the anchorages to which it is attached
should be increased a number of times over that of the lanyard.
Extreme care should be taken in considering a horizontal lifeline
for multiple tie-offs. The reason for this is that in multiple
tie-offs to a horizontal lifeline, if one employee falls, the
movement of the falling employee and the horizontal lifeline
during arrest of the fall may cause other employees to fall
also. Horizontal lifeline and anchorage strength should be increased
for each additional employee to be tied off. For these and other
reasons, the design of systems using horizontal lifelines must
only be done by qualified persons. Testing of installed lifelines
and anchors prior to use is recommended.
(7)
The strength of an eye-bolt is rated along the axis of the bolt
and its strength is greatly reduced if the force is applied
at an angle to this axis (in the direction of shear). Also,
care should be exercised in selecting the proper diameter of
the eye to avoid accidental disengagement of snap-hooks not
designed to be compatible for the connection.
(8)
Due to the significant reduction in the strength of the lifeline/lanyard
(in some cases, as much as a 70 percent reduction), the sliding
hitch knot (prusik) should not be used for lifeline/lanyard
connections except in emergency situations where no other available
system is practical. The "one-and-one" sliding hitch
knot should never be used because it is unreliable in stopping
a fall. The "two-and-two," or "three-and-three"
knot (preferable) may be used in emergency situations; however,
care should be taken to limit free fall distance to a minimum
because of reduced lifeline/lanyard strength.
(i)
"Vertical lifeline considerations." As required by
the standard, each employee must have a separate lifeline [except
employees engaged in constructing elevator shafts who are permitted
to have two employees on one lifeline] when the lifeline is
vertical. The reason for this is that in multiple tie-offs to
a single lifeline, if one employee falls, the movement of the
lifeline during the arrest of the fall may pull other employees'
lanyards, causing them to fall as well.
(j)
"Snap-hook considerations." (1) Although not required
by this standard for all connections until January 1, 1998,
locking snaphooks designed for connection to suitable objects
(of sufficient strength) are highly recommended in lieu of the
nonlocking type. Locking snaphooks incorporate a positive locking
mechanism in addition to the spring loaded keeper, which will
not allow the keeper to open under moderate pressure without
someone first releasing the mechanism. Such a feature, properly
designed, effectively prevents roll-out from occurring.
(2)
As required by 1926.502(d)(6), the following connections must
be avoided (unless properly designed locking snaphooks are used)
because they are conditions which can result in roll-out when
a nonlocking snaphook is used:
(i)
Direct connection of a snaphook to a horizontal lifeline.
(ii) Two (or more) snaphooks connected to one dee-ring.
(iii) Two snaphooks connected to each other.
(iv) A snaphook connected back on its integral lanyard.
(v) A snaphook connected to a webbing loop or webbing lanyard.
(vi) Improper dimensions of the dee-ring, rebar, or other connection
point in relation to the snaphook dimensions which would allow
the snaphook keeper to be depressed by a turning motion of the
snaphook.
(k)
"Free fall considerations." The employer and employee
should at all times be aware that a system's maximum arresting
force is evaluated under normal use conditions established by
the manufacturer, and in no case using a free fall distance
in excess of 6 feet (1.8 m). A few extra feet of free fall can
significantly increase the arresting force on the employee,
possibly to the point of causing injury. Because of this, the
free fall distance should be kept at a minimum, and, as required
by the standard, in no case greater than 6 feet (1.8 m). To
help assure this, the tie-off attachment point to the lifeline
or anchor should be located at or above the connection point
of the fall arrest equipment to belt or harness. (Since otherwise
additional free fall distance is added to the length of the
connecting means (i.e. lanyard)). Attaching to the working surface
will often result in a free fall greater than 6 feet (1.8 m).
For instance, if a 6 foot (1.8 m) lanyard is used, the total
free fall distance will be the distance from the working level
to the body belt (or harness) attachment point plus the 6 feet
(1.8 m) of lanyard length. Another important consideration is
that the arresting force which the fall system must withstand
also goes up with greater distances of free fall, possibly exceeding
the strength of the system.
(l)
"Elongation and deceleration distance considerations."
Other factors involved in a proper tie-off are elongation and
deceleration distance. During the arresting of a fall, a lanyard
will experience a length of stretching or elongation, whereas
activation of a deceleration device will result in a certain
stopping distance. These distances should be available with
the lanyard or device's instructions and must be added to the
free fall distance to arrive at the total fall distance before
an employee is fully stopped. The additional stopping distance
may be very significant if the lanyard or deceleration device
is attached near or at the end of a long lifeline, which may
itself add considerable distance due to its own elongation.
As required by the standard, sufficient distance to allow for
all of these factors must also be maintained between the employee
and obstructions below, to prevent an injury due to impact before
the system fully arrests the fall. In addition, a minimum of
12 feet (3.7 m) of lifeline should be allowed below the securing
point of a rope grab type deceleration device, and the end terminated
to prevent the device from sliding off the lifeline. Alternatively,
the lifeline should extend to the ground or the next working
level below. These measures are suggested to prevent the worker
from inadvertently moving past the end of the lifeline and having
the rope grab become disengaged from the lifeline.
(m)
"Obstruction considerations." The location of the
tie-off should also consider the hazard of obstructions in the
potential fall path of the employee. Tie-offs which minimize
the possibilities of exaggerated swinging should be considered.
In addition, when a body belt is used, the employee's body will
go through a horizontal position to a jack-knifed position during
the arrest of all falls. Thus, obstructions which might interfere
with this motion should be avoided or a severe injury could
occur.
(n)
"Other considerations." Because of the design of some
personal fall arrest systems, additional considerations may
be required for proper tie-off. For example, heavy deceleration
devices of the self-retracting type should be secured overhead
in order to avoid the weight of the device having to be supported
by the employee. Also, if self-retracting equipment is connected
to a horizontal lifeline, the sag in the lifeline should be
minimized to prevent the device from sliding down the lifeline
to a position which creates a swing hazard during fall arrest.
In all cases, manufacturer's instructions should be followed.
[59
FR 40743, Aug. 9, 1994; 60 FR 5131, Jan. 26, 1995]
OSHA
Regulations (Standards - 29 CFR) - Table of Contents OSHA Regulations
(Standards - 29 CFR) - Table of Contents
[62
FR 40141, July 25, 1997]
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