Buck Tech Inst - Warn Doc (02/07/18)
Page
12 of 13
P/N 230420
3.
Users must follow manufacturer’s instructions for proper fit and sizing, paying particular
attention to ensure that buckles are
connected and aligned correctly, leg straps and shoulder straps are kept snug at all times, chest straps are located in the middle chest
area, and leg straps are positioned and snug to avoid contact with the genitalia should a fall occur.
4.
Full Body Harnesses which meet ANSI/ASSE Z359.11 are intended to be used with other components of a Personal Fall Arrest
system that limit maximum arrest forces to 1800 pounds (8 kN) or less.
5.
Suspension intolerance, also called suspension trauma or orthostatic intolerance, is a serious condition that can be controlled with
good harness design, prompt rescue, and post fall suspension relief devices. A conscious user may deploy a suspension relief device
allowing the user to remove tension from around the legs, freeing blood flow, which can delay the onset of suspension intolerance. An
attachment element extender is not intended to be attached directly to an anchorage or anchorage connector for fall arrest. An energy
absorber must be used to limit maximum arrest forces to 1800 pounds (8 kN). The length of the attachment element extender may
affect free fall distances and free fall clearance calculations.
6.
Full Body Harness (FBH) Stretch, the amount the FBH component of a Personal Fall Arrest system will stretch and deform during a
fall, can contribute to the overall elongation of the system in stopping a fall. It is important to include the increase in fall distance created
by FBH Stretch, as well as the FBH connector length, th
e settling of the user’s body in the FBH, and all other contributing factors when
calculating total clearance required for a particular fall arrest system.
7.
When not in use, unused lanyard legs that are still attached to a Full Body Harness D-ring should not be attached to a work
positioning element or any other structural element on the Full Body Harness unless deemed acceptable by the competent person and
manufacturer of the lanyard. This is especially important when using some types of “Y” style lany
ards, as some load may be
transmitted to the user through the unused lanyard leg if it is not able to release from the harness. The lanyard parking attachment is
generally located in the sternal area to help reduce tripping and entanglement hazards.
8.
Loose ends of straps can get caught in machinery or cause accidental disengagement of an adjuster. All Full Body Harnesses shall
include keepers or other components which serve to control the loose ends of straps.
9.
Due to the nature of soft loop connections, it is recommended that soft loop attachments only be used to connect with other soft
loops or carabiners. Snap hooks should not be used unless approved for the application by the manufacturer.
Sections 10-16 provide additional information concerning the location and use of various attachments that may be provided
on this FBH
.
10. Dorsal
–
The dorsal attachment element shall be used as the primary fall arrest attachment, unless the application allows the use
of an alternate attachment. The dorsal attachment may also be used for travel restraint or rescue. When supported by the dorsal
attachment during a fall, the design of the Full Body Harness shall direct load through the shoulder straps supporting the user, and
around the thighs. Supporting the user, post fall, by the dorsal attachment will result in an upright body position with a slight lean to the
front with some slight pressure to the lower chest. Considerations should be made when choosing a sliding versus fixed dorsal
attachment element. Sliding dorsal attachments are generally easier to adjust to different user sizes, and allow a more vertical rest
position post fall, but can increase FBH Stretch.
11. Sternal
–
The sternal attachment may be used as an alternative fall arrest attachment in applications where the dorsal attachment
is determined to be inappropriate by a competent person, and where there is no chance to fall in a direction other than feet first.
Accepted practical uses for a sternal attachment include, but are not limited to, ladder climbing with a guided type fall arrestor, ladder
climbing with an overhead self-retracting lifeline for fall arrest, work positioning, and rope access. The sternal attachment may also be
used for travel restraint or rescue.
When supported by the sternal attachment during a fall, the design of the Full Body Harness shall direct load through the shoulder
straps supporting the user, and around the thighs. Supporting the user, post fall, by the sternal attachment will result in roughly a sitting
or cradled body position with weight concentrated on the thighs, buttocks and lower back. Supporting the user during work positioning
by this sternal attachment will result in an approximate upright body position.
If the sternal attachment is used for fall arrest, the competent person evaluating the application should take measures to ensure that a
fall can only occur feet first. This may include limiting the allowable free fall distance. - It may be possible for a sternal attachment
incorporated into an adjustable style chest strap to cause the chest strap to slide up and possibly choke the user during a fall,
extraction, suspension, etc. The competent person should consider Full Body Harness models with a fixed sternal attachment for these
applications.
12. Frontal
–
The frontal attachment serves as a ladder climbing connection for guided type fall arrestors where there is no chance to
fall in a direction other than feet first or may be used for work positioning. Supporting the user, post fall or during work positioning, by
the frontal attachment will result in a sitting body position, with the upper torso upright, with weight concentrated on the thighs and
buttocks. When supported by the frontal attachment the design of the Full Body Harness shall direct load directly around the thighs and
under the buttocks by means of the sub-pelvic strap.
If the frontal attachment is used for fall arrest, the competent person evaluating the application should take measures to ensure that a
fall can only occur feet first. This may include limiting the allowable free fall distance.
13. Shoulder
–
The shoulder attachment elements shall be used as a pair, and are an acceptable attachment for rescue, and
entry/retrieval. The shoulder attachment elements shall not be used for fall arrest. It is recommended that the shoulder attachment
elements be used in conjunction with a yoke which incorporates a spreader element to keep the Full Body Harness shoulder straps
separate.
