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Core and Removal Criteria for Web Slings
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Section 1.1 - PURPOSE
1.1.1 The purpose of this page is to provide guidelines for the qualified person
responsible for web sling selection, rigging, inspection and use.
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Section 1.2 - MECHANICAL CONSIDERATIONS
1.2.1 Determine weight of the load. The weight of the load shall be within the rated
capacity of the web sling.
1.2.2 Select a web sling having suitable characteristics for the type of load, hitch and
environment.
1.2.3 Web slings shall not be loaded in excess of the rated capacity shown on the
attached identification tag. Consideration shall be given to the sling to load angle
(See figure 22) which affects rated capacity.
1.2.4 Web slings with fittings, which are used in a choker hitch, shall be of sufficient
length to assure that the choking action is on the webbing, and never on the fitting.
1.2.5 Web slings used in a basket hitch should have the load controlled to prevent slippage.
1.2.6 The opening in fittings shall be the proper shape and size to ensure that the fitting
will seat properly in the hook or other attachments.
1.2.7 Web slings shall always be protected from being cut or damaged by corners, edges,
protrusions or abrasive surfaces.
1.2.8 Web slings should not be dragged on the floor or over abrasive surfaces.
1.2.9 Web slings shall not be twisted, shortened, lengthened, tied in knots, or joined by
knotting. Web slings shall be shortened, lengthened, or adjusted only by methods
approved by the manufacturer.
1.2.10 Web slings should not be pulled from under loads when the load is resting on the
web sling. Loads resting on web slings could damage the sling.
1.2.11 Do not drop web slings equipped with metal fittings.
1.2.12 Web slings that appear to be damaged shall not be used unless inspected and
accepted as usable under Section 1.3, 1.4, and 1.5.
1.2.13 The web sling shall be hitched in a manner providing control of the load.
1.2.14 Personnel, including portions of the human body, shall be kept from between the
sling and the load, and from between the sling and the crane hook or hoist hook.
1.2.15 Personnel shall not stand under suspended loads. Personnel should stand clear of
suspended loads.
1.2.16 Personnel shall not ride the web sling or the load being lifted.
1.2.17 Shock loading should be avoided.
1.2.18 Twisting and kinking the legs shall be avoided.
1.2.19 Load applied to the hook shall be centered in the base of the hook to prevent point
loading on the hook.
1.2.20 During a lift, with or without the load, personnel shall be alert for possible snagging.
1.2.21 The web slings legs should contain or support the load from the sides above the
center of gravity when using a basket hitch.
1.2.22 Web slings shall be long enough so that the rated capacity (Working Load Limit) is adequate when the sling to load angle is taken into consideration (See 2.10)
1.2.23 Only web slings with legible identification tags shall be used.
1.2.24 Tags and labels should be kept away form the load, hook and point of choke.
1.2.25 Web slings shall not be constricted or bunched between the ears of a clevis or shackle.
1.2.26 Place blocks under load prior to setting down the load to allow removal of the web sling, if applicable.
1.2.27 Web slings shall not be used as bridles on suspended personnel platforms.
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Section 1.3 - ENVIRONMENTAL CONSIDERATIONS
1.3.1 Web slings should be stored in a cool, dry and dark place when not in use to
prevent loss of strength through exposure to ultra-violet light. Web slings shall not
be stored in chemically active environments.
1.3.2 Chemically active environments can affect the strength of synthetic web slings in varying degrees ranging from little to total degradation. The web sling manufacturer or qualified person should be consulted before slings are used in
chemically active environments.
1.3.2.1 Acids
1.3.2.1.1 Nylon is subject to degradation in acids, ranging from little to total
degradation.
1.3.2.1.2 Polyester is resistant to many acids, but is subject to degradation, ranging from little to moderate in some acids.
1.3.2.1.3 Each application shall be evaluated, taking into consideration the following:
a. Type of Acid
b. Exposure Conditions
c. Concentration
d. Temperature
1.3.2.2 Alkalis
1.3.2.2.1 Polyester is subject to degradation in alkalis, ranging from little to total
degradation.
1.3.2.2.2 Nylon is resistant to many alkalis, but is subject to degradation ranging
from little to moderate in some alkalis.
1.3.2.2.3 Each application shall be evaluated, taking into consideration the
following:
a. Type of Alkalis
b. Exposure Conditions
c. Concentration
d. Temperature
1.3.3 Nylon and polyester slings shall not be used in contact with objects or at temperatures
in excess of 194 degrees f (90c) or below 40 degrees f , -40 degrees C.
1.3.4 Web slings incorporating aluminum fittings shall not be used where fumes, vapors,
sprays, mists or liquids of alkalis and/or acids are present.
1.3.5 Environments in which synthetic web slings are continuously exposed to ultraviolet
light can affect the strength of synthetic web slings in varying degrees
ranging from slight to total degradation.
CAUTION: Degradation can take place without visible indications.
a. Factors, which affect the degree of strength loss, are:
1. Length of time of continuous exposure
2. Web sling construction and design
3. Other environmental factors such as weather conditions and geographic location
b. Suggested procedures to minimize the affects of sunlight or ultra-violet light.
1. Store web slings in a cool, dry and dark place when not being used for
prolonged periods of time.
c. Some visual indications of sunlight or ultra-violet degradation are:
1. Bleaching out of web sling color
2. Increased stiffness of web sling material
3. Surface abrasion in areas not normally in contact with the load
d. Proof Testing Warning: Slings used in environments where they are subject to
continuous exposure to sunlight or ultra-violet light shall be proof tested to twice
the rated capacity semi-annually, or more frequently depending on severity of
exposure.
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Section 1.4 - INSPECTION
1.4.1 Type of Inspection
a. Initial Inspection: Before any new or repaired web sling is placed in service, it
shall be inspected by a designated person to ensure that the correct web sling is
being used, as well as to determine that the web sling meets the requirements of
this specification.
b. Frequent Inspection: This inspection should be conducted by the person handling the sling each time the sling is used.
c. Periodic Inspection: This inspection shall be conducted by designated personnel.
Frequency of inspection should be based on:
1. Frequency of web sling use
2. Severity of service conditions
3. Experience gained on the service life of web slings used in similar applications
4. Inspections should be conducted at least annually
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Section 1.5 - REMOVAL FROM SERVICE
1.5.1 Treated and untreated nylon and polyester webbing, used to fabricate synthetic
slings, per class 5 and class 7 rated capacity charts, may contain red yarn woven
into the core of the webbing to serve only as one of many aids in determining
whether and when a sling should be removed from service.
1.5.2 A web sling shall be removed from service if any of the following are visible:
a. If sling rated capacity or sling material identification is missing or not readable
b. Acid or alkalis burns
c. Melting, charring or weld spatters on any part of the web sling
d. Holes, tears, cuts, snags or embedded particles
e. Broken or worn stitching in load bearing splices
f. Excessive abrasive wear
g. Knots in any part of the web sling
h. Excessive pitting, or corrosion, or cracked, or distorted, or broken fittings.
i. Any other visible damage that causes doubt as to the strength of the sling
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Section 1.6 - INSPECTION RECORDS
1.6.1 Written inspection records, utilizing the identification for each sling as established
by the user, should be kept on file for all web slings. These records should show a
description of the sling and its condition on each periodic inspection.
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Section 1.7 - REPAIR OF WEB SLINGS
1.7.1 Sling webbing with structural damage shall never be repaired. (See 1.5.1)
1.7.2 Type I and Type II web slings, and other web slings utilizing hardware, may be rewebbed utilizing existing fittings. It shall be the responsibility of the manufacturer
repairing the web sling to determine if the hardware is re-usable.
1.7.3 Slings shall be repaired only by a sling manufacturer or a qualified person. When repaired, a sling shall be marked to identify the repair agent.
1.7.4 All re-webbed Type I and Type II, and other web slings utilizing fittings, shall be proof tested to two (2) times their vertical rated capacity before being placed back into service. A certificate of proof testing shall be provided.
1.7.5 Temporary repairs of webbing, fittings, or stitching shall not be permitted.
1.7.6 Repaired slings shall be proof tested to two (2) times its assigned rated capacity
before being put back into service.
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