slings safety use inspection

44909.469-2251 www.lift-it.com

GEN

ERAL

INFO

. AND

TRAININGLift Planning and Evaluation

Before using any rigging device it is important to plan your work and work your plan. The front end time required to develop a successful lift plan may seem unnecessary for small or non-consequential loads. Theres always enough time to pre-plan critical lifts. After an incident involving what seemed to be a non-consequential amount of weight, the time required to mitigate the mess will dwarf the time spent on what was thought to be an unnecessary lift planning session. Theres always enough time to do the job right, the second time. We encourage you to make the front end investment in lift planning and successful rigging, before each and every lift.

A trained, qualified and knowledgeable user must take into account the following factors and issues and consider all relevant factors not addressed. Among the factors related specifically to slings and rigging, users must perform several activities, including (but not limited to) the following items:

Fee based engineering services, including analysis and consideration of the above variables is available.Please contact us for details.

ENGINEERING SERVICES

Single or Multiple Crane/HoistsMaximum/Planned Operating RadiusAllowable Load (From Load Chart)Ratio of Lift to Allowable LoadClearance between Boom and LiftClearance to Surrounding FacilitiesPower Lines and Environmental HazardsEnsure a Clear Load PathEmergency/Contingency Set Down AreaThorough Equipment Inspection

Sling selection: Type and CapacityLoad ControlLift Point over the CGAppropriate Hitch for CG and Load ControlCoordination of Multiple Slings Positive Sling to Load EngagementCoefficient of Friction: Sling to LoadLoad is Free to Move and is not SnaggedSling Capacity is Adequate (Angle and Tension)Adequate Sling Protection

EQUIPMENT AND LIFT CRITERIA RIGGING CONSIDERATIONS

WindWeatherVisibilityObject TemperatureEnvironmental TemperatureChemical Conditions and Exposure Stability of the GroundUnderground Installations

WeightDimensionsCenter of Gravity (CG)Attachment Point IntegrityStructural Stability: Bend and FlexSusceptibility to Crushing or CompressionLoose Parts that could fall from the LoadCombination Loads-Drain FluidsDamaging Surfaces and/or Edges

ENVIRONMENTAL CONSIDERATIONS LOAD CONSIDERATIONS

PERSONNEL CONSIDERATIONS

Area Clear of Unnecessary PersonnelPersonnel are Trained and QualifiedPre-Lift Plan and Meeting

Signals: Visual, Audible, Electronic, etc.Tag Lines and Spotter RequirementsPersonnel Away from Load and Other Dangers

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Purchase and Use Considerations

RIGGING FACTORS

TRAINING

SLING PROTECTION

SLING SELECTION Prior to selection, read and understand the information contained in our catalog and your responsibilities as detailed in all applicable regulations and standards. Select the sling with suitable characteristics for the load, environment and configuration of lift.

LOAD WEIGHT: Is the weight of the load within the Work Load Limit of the sling(s)?

WEIGHT DISTRIBUTION: Uneven load weight distribution imposes disproportionate loading on the individual sling legs.

ADEQUATE SLING LENGTH: Slings must be long enough to ensure the Work Load Limit is adequate, when the sling-to-load angle is taken into account. Inadequate consideration has caused under-rated slings to fail.

LOAD CONTROL: The sling user is responsible for load control. Slings must be rigged in a manner that provides for control of the load. Balancing and supporting the load, from the sides above the center of gravity is critical. Use more than one sling to balance the load so it will not tilt when lifted.

CENTER OF GRAVITY: The lifting mechanism must be positioned directly over the center of gravity, before the load is lifted. If this is not done, the load will change out and the center of gravity will end up under the lifting fixture. The center of gravity must be addressed and determined through careful experimentation or calculation.

POSITIVE LOAD ENGAGEMENT: Poor or inadequate sling-to-load engagement results in the sling skipping across load edges. This movement can result in catastrophic sling failure and uncontrolled load descent. Slings equipped with protection have also been cut because of poor sling-to-load engagement.

All sling users must be trained on the proper use of slings.

The American Society of Mechanical Engineers, in the ASME B30.9 Sling Safety Standard, clearly establishes the requirement for training. Section 9-X.1-Training states, Sling users shall be trained in the selection, inspection, cautions to personnel, effects of the environment and rigging practices, covered by this chapter.

DOL/OSHA Guidance on Safe Sling Use (29 CFR 1910.184) states that a qualified person is one: who by possession of a recognized degree or certificate of professional standing in an applicable field, or who, by extensive knowledge, training and experience has successfully demonstrated the ability to solve or resolve problems relating to the subject matter and work.

It is important that all sling users be knowledgeable about the safe and proper use and application of slings and be thoroughly familiar with manufacturers recommendations and all safety information provided with products. In addition, sling users need to be aware of their responsibilities as outlined in all applicable standards and regulations. If you are unsure whether you are properly trained or knowledgeable, DO NOT use slings or rigging devices until you are absolutely sure of what you are doing.

Slings must be protected from damaging edges, corners, protrusions or abrasive surfaces by materials of sufficient strength, thickness and construction to prevent sling damage and failure.

There are a variety of ways to employ sling protection and prevent sling damage. Regardless of the particular method chosen, the goal is to ensure that the sling maintains its ability to securely lift the load while avoiding contact with damaging or abrasive surfaces under tension. A qualified person must carefully consider the appropriate means to accomplish this goal by selecting sling protection appropriate for the types of exposure damage. Sling protection should not be makeshift (i.e., selecting and using cardboard, work gloves or other such items that were not designed to serve as protection devices).

Sling protection may not prevent cutting or other forms of damage. To avoid severe personal injury or death, personnel should be kept away from the load and never be under or near the load, while it is being lifted or suspended. Personnel should never be next to rigging under tension.

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GEN

ERAL

INFO

. AND

TRAININGPurchase and Use Considerations

CHEMICAL FACTORS

ENVIRONMENTAL CONSIDERATIONS

Chemically active environments can affect the strength of rigging products in varying degrees from moderate to total degradation. The materials used in the construction of slings and components must be compatible with the mechanical and environmental requirements imposed. Fumes, sprays, mists, vapors and liquids of acids or alkalis can degrade rigging products. The chemical agents must be identified. Specific time, temperature and concentration factors will assist the user and manufacturer in the selection of the appropriate sling material components.

It may be necessary to conduct an on-site suitability test. A sample would be subjected to exposure, under no load. The length of exposure must be determined by the qualified person. After exposure, the sample would be pulled to destruction to determine the retention of tensile strength and evaluated, comparing test results with the strength of an unexposed, control sample. We prefer application testing to chemical analysis of independent chemical agents done by referencing various charts or technical bulletins. Application testing (where the rubber meets the road) will also provide more accurate information on the cumulative effects of multiple chemical agents. We will match your efforts and assist you in determining the most suitable materials for your specific application.

TEMPERATURE:

Conventional synthetic products cannot be used in environmental or contact temperatures exceeding 194F/90C or below -40F/-40C. Applications outside those parameters can be addressed by consulting us for specific recommendations.

ULTRAVIOLET (UV) LIGHT DEGRADATION:

Exposure to sources of ultraviolet (UV) light affects the strength of synthetic products in varying degrees from slight to total degradation. Factors which play a part in the degree of strength loss are length of exposure, sling construction and design. Other environmental factors such as weather conditions, elevation and geographic location also affect the degree of degradation.

The Web Sling and Tie Down Association (WSTDA) conducted tests to determine the affects of strength loss, as a result of ultraviolet (UV) exposure. The report, WSTDA-UV-Sling-2003 is available at www.wstda.com

Many different variables were analyzed in slings that were exposed for a period of 36 months. Nylon and polyester endless slings featuring: treated and untreated webbing, 6800 Lbs. (class 5) and 9800 Lbs. (class 7) materials and single and double ply constructions were evaluated.

Initially, nylon web slings lost strength at a slower rate, when compared to polyester slings, but continued to lose strength as exposure time was extended. The loss of strength for nylon slings can be 40 to 60% after exposure periods ranging from 12 to 36 months.

In the first year of the study, polyester web slings lost strength at a greater rate, when compared to nylon slings. Loss in strength for polyester slings was approximately 30% after 12 months exposure. Polyester sling strength loss seemed to subside and level off after the initial 12 month period.

When slings are not in use, store them in a dark, cool, dry location, free from mechanical and environmental damage.

MOISTURE ABSORPTION:

When nylon products are wet there is an approximate strength loss of 15%. This loss of strength is documented in the 1988 DuPont Technical Information Multifiber Bulletin X272, page 6. Nylon sling strength returns when the sling dries completely. Polyester and High Performance Fiber strength is unaffected by moisture absorption.

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Sling Hitches

A BASKET WORK LOAD LIMIT OF 10,000 LBS.CHANGES AS THE SLING TO LOAD ANGLE CHANGES

AT 90 - WORK LOAD LIMIT = 5,000 LBS. PER LEGAT 60 - WORK LOAD LIMIT = 4,330 LBS. PER LEGAT 45 - WORK LOAD LIMIT = 3,536 LBS. PER LEGAT 30 - WORK LOAD LIMIT = 2,500 LBS. PER LEG

SLING-TO-LOAD ANGLE (DEGREES) 90 60 45 30

WORK LOAD LIMIT X LOSS FACTOR 10,000 Lbs. x 1.000 10,000 Lbs. x .8660 10,000 Lbs. x .7071 10,000 Lbs. x .5000

REDUCED WORK LOAD LIMIT 10,000 Lbs. 8660 Lbs. 7071 Lbs. 5000 Lbs.

Sling-To-Load Angle

The Sling-to-Load Angle is the angle formed between a horizontal line and the sling leg or body. The Sling-to-Load Angle has a dramatic effect on sling Work Load Limits. Slings with adequate capacity to handle the scale weight of the load have catastrophically failed because the Sling-to-Load Angle and increased tension were not taken into account.

This principle applies in a number of conditions, including when one sling is used to lift at an angle and when a basket hitch or multi-leg bridle sling is used. When selecting a sling, always consider the Sling-to-Load Angle and the tension that will be applied to the sling. As the Sling-To-Load Angle decreases, the tension on the sling leg(s) increases.

Illustrated left- Increased tension ismagnified by any change from verticalto horizontal lifting. Increased tensionis imposed on the sling leg(s) when thelegs are used at angles less than 90.

Slings must be securely attached to the load and rigged in a manner to provide for load control to prevent slipping, sliding and/or loss of the load. A trained, qualified and knowledgeable user must determine the most appropriate method of rigging to help ensure load control and a safe lift.

For years sling users have used angles to determine sling adequacy. One approach has been to determine the Sling-to-Load Angle and multiply the Work Load Limit by the Loss Factor for the specific angle. The result is the REDUCED WORK LOAD LIMIT.

1. Calculate the Sling to Load Angle.

2. Determine the corresponding Loss Factor.

3. Multiply the Work Load Limit (per leg) by the Loss Factor to determine the reduced Work Load Limit (per Leg).

The result is the reduced Work Load Limit.

A

SLING-TO-LOAD ANGLE

The horizontal angle formed between the sling leg and the top of the load.

Sling angles less than 30 should not be used, unless approved by a qualified person.

SLING ANGLE - REDUCED WORK LOAD METHOD

LOSS FACTOR CHART

Angle A Degrees

Loss FactorAngle A Degrees

Loss Factor

90 1.000 55 .8192

85 .9962 50 .7660

80 .9848 45 .7071

75 .9659 40 .6428

70 .9397 35 .5736

65 .9063 30 .5000

60 .8660 25 .4226

3,536Lbs.

3,536Lbs.

2,500Lbs.4,330Lbs.

4,330Lbs.5,000

Lbs.5,000Lbs.

2,500Lbs.

CHOKER HITCH VERTICAL HITCH BASKET HITCH

Sling passes through one end around the load, while the other end is placed on the hook. Load control is limited with only one sling rigged in a choker hitch. A choker hitch will never provide full 360 degree contact. For full contact use a Double Wrap Choke Hitch. See page 24. The Choke Point should always be on the sling body, not on the sling eye, fitting, base of the eye or fitting, splice or tag.

One end is on the hook, while the other end is attached directly to the load. Use a tagline to prevent load rotation.

The sling cradles the load while both eyes are attached overhead. As with the choker hitch, more than one sling may be necessary to help ensure load control.

Slings carry their loads in one of three primary sling hitches. Most slings can be used in all three sling hitches, but some slings are designed for use in only one hitch. Slings have the largest Work Load Limit when used in a basket hitch. The vertical hitch Work Load Limit is 50% of the basket hitch. The synthetic choker hitch Work Load Limit is a maximum of 80% of the vertical hitch Work Load Limit.

10,000 Lbs. 10,000 Lbs.10,000 Lbs.

10,000 Lbs.

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GEN

ERAL

INFO

. AND

TRAINING

10,000

Sling angles less than 30 should not be used, unless approved by a qualified person.

Sling-To-Load Angle

SLING ANGLE INCREASED TENSION METHOD

Choker Hitch Angle

Whenever a sling is used in a choker hitch and results in a Choker Hitch Angle less than 120 degrees, Choker Work Load Limits must be adjusted. Determine the Choker Hitch Angle and multiply the Choker Hitch Work Load Limit by the appropriate Reduction Factor. The result is the actual, reduced Choker Work Load Limit.

A more salient approach to determine sling adequacy is the calculation of INCREASED TENSION resulting from the Sling-to-Load Angle. This approach has the distinct advantage of enabling the sling user to determine the required sling strength requirement. The user must first determine the angle and multiply the load weight (per leg) by the tension factor for the specific angle. The result is the INCREASED TENSION or actual loading on the sling leg(s).

1. Calculate the Sling to Load Angle.

2. Determine the corresponding Tension Factor.

3. Multiply the load weight (per leg) by the Tension Factor to determine the increased tension on the sling leg(s).

TENSION FACTOR CHART

ANGLE A DEGREES

TENSION FACTOR

ANGLE A DEGREES

TENSION FACTOR

90 1.000 55 1.221

85 1.004 50 1.305

80 1.015 45 1.414

75 1.035 40 1.555

70 1.064 35 1.742

65 1.104 30 2.000

60 1.155 25 2.364

CHOKER HITCH ANGLE REDUCTION CHART

Choker Hitch Angle (Degrees)

Reduction Factor

120 - 180 1.00

105 - 120 .82

90 - 105 .71

60 - 90 .58

0 - 60 .50

0-30

60

90

120180135135

SLING TENSION INCREASES AS THESLING-TO-LOAD ANGLE DECREASES

AT 90 - SLING TENSION = 5,000 PER LEG AT 60 - SLING TENSION = 5,775 PER LEGAT 45 - SLING TENSION = 7,070 PER LEGAT 30 - SLING TENSION = 10,000 PER LEG

5,000Lbs.

5,000Lbs.

10,000

SLING-TO-LOAD ANGLE(DEGREES)

90 60 45 30

LOAD WEIGHTX TENSION FACTOR

10,000 Lbs.X 1.000

10,000 Lbs.X 1.155

10,000 Lbs.X 1.414

10,000 Lbs.X 2.000

INCREASED SLING TENSION 10,000 Lbs. 11,550 Lbs. 14,140 Lbs. 20,000 Lbs.

Two examples of slings used at 0 degree Choker Hitch Angle.

Controlling a load witha high center of gravity.

Rigging from a Supporting Structure.

Supporting StructureChoker Hitch Angle

Choker Hitch

Angle at 0 degree.

Choker Hitch

Angle at 0 degree.

10,000Lbs.

LOAD

10,000Lbs.

5,775Lbs.

5,775Lbs.

10,000

7,070Lbs.

7,070Lbs.

10,000

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It is always important to rig and control the load so that stability is achieved. Determining the location of the Center of Gravity (CG) is vital to achieving load control. The CG is the point where the load weight is concentrated and is the balance point for an object. The Center of Gravity when suspended will:

1. Unless restrained, the CG will move directly under the suspension point.

2. The CG will move to the lowest point possible.

For best control, attach the slings above the CG. When this is not possible keep the CG contained with three or four sling legs or use basket or choker hitches with wraps. These measures may not guarantee load control. The user must be assured, based upon the specific application that selected methods are suitable and comply with all applicable standards and regulations.

Multiple factors must be taken into consideration to ensure that load control and stability are attained. A load with a high center of gravity can rotate in certain sling hitches.

Lift point is below CG

and only two slings used.

StableUnstable

(After)(Before)

Lift point is not over CG.

Load will shift until CG settles

below the suspension point.

Calculating the tension imposed on slings or individual legs of a multi-part sling system will enable the sling user to select slings with adequate Work Load Limits.

1) Determine the Load Angle Factor (LAF):

Divide the leg Length (L) by the Headroom (H)

L H = LAF

Example: 20 15 = 1.33 Load Angle Factor (LAF)

2) Determine the Share of the Load (SOL) for the individual sling legs:

Divide the load weight by the number of sling legs.

Load weight number of legs = Share of the Load (SOL)

Example: 12,000 Lbs. 3 legs = 4,000 Lbs. (SOL)

3) Multiply Load Angle Factor by the Share of the Load

to determine Sling Tension.

Load Angle Factor x Share of the Load = Tension

LAF x SOL = Tension

Example: 1.33 x 4,000 = 5,320 Lbs.

H(15 Ft.)

Please Note: Tension calculations are based upon:1) Sling attachment points being equidistant from the center of gravity.2) Sling attachment points being equidistant to each other.3) Sling attachment points being on the same horizontal plane.4) Equal sling leg lengths.

L(20 Ft.)

Use the following steps to calculate the tension imposed upon the individual sling legs, when you know the leg Length (L) and Headroom (H).

Sling Tension - Leg Length/Headroom

Unstable

Center of Gravity (CG)

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GEN

ERAL

INFO

. AND

TRAININGAdvanced Tension Calculations

Different, complex calculations are required to determine sling tension when the slings are attached at different horizontal planes. (Please note: Twin-Path Adjustable Bridle is depicted).

More complex calculations are required when the slings are not placed equidistantly from the center of gravity or when the Center of Gravity is not equidistant from the sling attachment points. The PROPORTIONAL SHARE OF THE LOAD (SOL) must be determined and multiplied by the LOAD ANGLE FACTOR (LAF) to determine SLING TENSION.

Sling tension is a function of sling length, distance between the sling attachment points and the spatial relationship between the sling attachment points and the Center of Gravity. An inverse proportional relationship exists between Distance and Share of the Load. If a sling is attached 25% of the distance from the Center of Gravity, that sling will carry 75% of the load weight. Likewise, if a sling is attached 75% of the distance from the Center of Gravity, that sling will carry 25% of the load weight.

SLING TENSION - DIFFERENT HORIZONTAL PLANES

SLING TENSION - PROPORTIONAL SHARE OF THE LOAD

55,000 Lbs.

5ft (H)

6ft (L1) 10.5ft (L2)

3ft. 9ft.

12ft.

6 FT. LEG3

12ProportionalShare ofthe Load

x

Load Angle Factor

= .25 Distance from CG .75 Share of the Load

.75 x 55,000 = 41,250 Lbs.

L1

H

6

5= = 1.20

x

Sling Tension 49,500 Lbs.

10.5 FT. LEG

x

9

12ProportionalShare ofthe Load

x

Load Angle Factor

= .75 Distance from CG .25 Share of the Load

.25 x 55,000 = 13,750 Lbs.

L2

H

10.5

5= = 2.10

Sling Tension 28,875 Lbs.

W x d2 x L1

(d2 x H1) + (d1 x H2)

14,600 x 12 x 13

(12 x 11.5) + (6 x 16)

2,277,600

234

9,733 Lbs.TENSION

13 FT. LEG (L1)SLING TENSION

W x d1 x L2

(d2 x H1) + (d1 x H2)

14,600 x 6 x 20

(12 x 11.5) + (6 x 16)

1,752,000

234

7,487 Lbs.TENSION

20 FT. LEG (L2)SLING TENSION

14,600 Lbs.

11.5 ft(H1)

18 ft

12 ft(d2)

6 ft(d1)

20 ft(L2)

16 ft(H2)

13 ft(L1)

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Rigging and Hitch Information

GENERAL INFORMATION ADJUSTABLE BASKET HITCH

Slings should be rigged in a manner that provides proper load control. It is dangerous to use only one sling to lift a load which tends to shift and slide out.

(One sling is depicted for illustrative purposes only).

Ensure that lifting devices are directly over the center of gravity. If this is difficult to determine, it must be discovered by cautious experimentation or calculation. Raise the load carefully. If the load is not level, lower and correct the position of the slings until the balance point is achieved and the load does not tilt.

The adjustable basket hitch allows the sling user to adjust the length of the legs to raise the load level. Adjustable hitches are particularly useful with loads having uneven load weight distribution resulting in an off-set center of gravity.

The Adjustable Basket Hitch Work Load Limit is identical to the regular basket hitch rating. The rating must be adjusted for the Sling-to-Load Angle. Another effective solution is an Adjustable Rope Sling featured on pages 127 and 128.

BASKET HITCHES

Inverted basket hitches are referred to as equalizing hitches because the sling is free to slip through the hook based upon the load weight distribution. Be sure to employ the four ends down, North to South, load engagement system.

Extra care should be taken when using slings in a basket hitch to balance the load to prevent slippage.

As with the choker hitch, more than one sling may be necessary to control the load.

Slings skipping through hardware components can become damaged. Balancing the load is critical and necessary to prevent sling damage and failure.

If practical, take a full wrap around the load to grip it firmly; be sure when using multiple slings that they do not cross over each other. Wrapping the load is a legitimate method of minimizing excessive sling length. Other methods, such as, twisting and knotting radically reduce sling Work Load Limits. When the load is wrapped the sling Work Load Limit is not increased, but load control is.

WrongInverted Basket(East to West)

RightEye & Eye Slings (North to South)

Right Wrong

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GEN

ERAL

INFO

. AND

TRAININGRigging and Hitch Information

CHOKER HITCHES

The choke hitch should always be pulled tight before the lift is made, not pulled down during the lift. A sling rigged in a choker hitch (not double wrapped) does not make full contact with the load. Use multiple slings to balance the load, and wrap the load to ensure full contact. Ensure multiple slings do not cross. Choke on opposite sides of the load, if this action will not damage the load and maintain load control.

For a tighter choke hitch, which provides full, 360 contact with the load, take a full wrap around the load before choking the sling. Ensure that multiple slings do not cross. When the load is wrapped the sling Work Load Limit does not increase, but load control does.

Please note:One sling is depicted for illustrative purposes only.

Always use a choker hitch when turning a load. If the sling is not rigged properly, the turning action will loosen the hitch, resulting in load slippage. Place sling eyes on top of the load, pointing the opposite direction of the turn. The body is then passed under the load and through both eyes. Blocking should be used to protect the sling and facilitate removal. Basket hitches should not be used to turn a load. Always downgrade the choker Work Load Limit when the angle of choke is less than 120, see page 20.

The sling should be of sufficient length to ensure that the choke action is on the sling body, never on the sling splice, fittings, tag, eye or at the base of the sling eye or fitting.

ADJUSTABLE HITCH DOUBLE CHOKER HITCH

The Adjustable Hitch allows the sling user to adjust the length of the legs to raise the load level. Adjustable hitches are particularly useful with loads having uneven load weight distribution resulting in an off-set center of gravity. The Work Load Limit for the Adjustable Hitch is identical to the normal Vertical Work Load Limit. The Adjustable Hitch works reasonably well on narrow web slings (1 and 2 in. widths) and roundslings rated at less than 7000 Lbs. choker.

The Double Choker Hitch if applied properly will facilitate equalization of the loading on the sling legs over the lifting hardware. If applied improperly, one of the legs will share a greater portion of the load and equalization will not occur. The Double Choker Hitch Work Load Limit is twice the regular Choker Hitch Work Load Limit.

smaller

larger

Right Wrong

Right Wrong

Right Wrong

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Web Sling Safety Information

SYNTHETIC WEB SLING SAFETY BULLETIN

To detect possible damage, you should perform a visual inspec-

tion of the entire sling and also feel along its entire length, as

some damage may be felt more than seen. You should look and

feel for any of the types of conditions listed in Table 1. Table 2

shows examples of some of these types of damage, but note that

they are relatively extreme examples provided for illustration

purposes only.

WARNING

SyntheticWeb Sling Safety Bulletin

2. Slings Must Be Regularly and Properly Inspected

1. All Sling Users Must be Trained and Knowledgeable 2a. How to inspect slings

2b.What to do if you identify damage in a sling

If you identify ANY of these types of damage in a sling,

even if the damage you feel or see

is not as extensive as shown in the pictures in Table 2. Slings that

are removed from service must be destroyed and rendered

completely unusable unless they can be repaired and proof-

tested by the sling's manufacturer or other qualified person. You

should never ignore sling damage or attempt to perform

temporary field repairs of damaged slings (e.g., tie knots in the

webbing, etc.).

remove

it from service immediately

All web sling users must be trained on the proper use of web

slings. The American Society of Mechanical Engineers, Safety

Standard for Slings (ASME B30.9) states:

OSHA Guidance on Safe Sling Use (29 CFR 1910.184) states that a

"qualified person" is one:

It is important that all sling users be knowledgeable about the

safe and proper use and application of slings and be thoroughly

familiar with the manufacturer's recommendations and safety

materials provided with each product. In addition, all sling users

need to be aware of their responsibilities as outlined in all

applicable standards and regulations.

If you are unsure whether you are properly trained and

knowledgeable, or if you are unsure of what the standards and

regulations require of you, ask your employer for information

and/or training use web slings until you are

absolutely sure of what you are doing. Remember, when it

comes to using web slings, lack of skill, knowledge and care can

result in severe or to you and others.

"Synthetic webbing sling users shall be trained in the

selection, inspection, cautions to personnel, effects of the

environment and rigging practices as covered" by Chapter 9-5.

"who, by possession of a recognized degree or certificate of

professional standing in an applicable field, or who, by

extensive knowledge, training, and experience, has

successfully demonstrated the ability to solve or resolve

problems relating to the subject matter and work."

DO NOT

INJURY DEATH

Even seemingly "minor" damage to a web sling can significantlyreduce its capacity to hold or lift objects and increases thechance that the sling will fail during use. For example, one slingmanufacturer has shown that a 3/8" (9.5mm) cut (much smallerthan the cut shown in Table 2) caused a sling to break under loadat almost half its non-damaged capacity. Therefore, it is veryimportant that web slings are regularly and properly inspected. If

you are not sure whether a sling is damaged, .DO NOT USE IT

The entire web sling must be and itshall be if ANY of the following aredetected:

inspected regularlyremoved from service

Table 1.Web sling removal from service criteria

This bulletin contains important safety information about the use of synthetic web slings.

However, it contain all the information you need to know about handling, liftingand manipulating materials and loads safely. Sling use is only one part of a lifting system and itis your responsibility to consider all risk factors prior to using any rigging device or product.

Failure to do this may result in severe or due to sling failure and/or loss of load.

DOES NOT

INJURY DEATH

All users must be trained in sling selection, use andinspection, cautions to personnel, environmentaleffects and rigging practices.

Do not exceed a slings rated capacity. Alwaysconsider the effect of sling angle and tension on theslings rated capacity.

Inspect sling for damage regularly, if the sling is

damaged, remove it from service.

Protect sling from damage. ALWAYS protect slings incontact with edges, corners, protrusions, or abrasivesurfaces with materials of sufficient strength,thickness and construction to prevent damage.

Do not stand on, under or near a loadwith thesling under tension. All personnel should be alert todangers of falling and/or uncontrolled loads, slingtension and the potential for snagging.

Maintain and store slings properly. Slings shouldbe protected from mechanical, chemical andenvironmental damage.

4

If sling identification tag ismissingornot readable.

Holes, tears, cuts, snagsorembeddedmaterials.

Brokenorwornstitches in the loadbearingsplices.

Knots inanypartof theslingwebbing.

Acidoralkaliburns.

Melting, charring or weld spatter on any part of the websling.

Excessiveabrasivewearorcrushedwebbing.

SignsofUltraviolet (UV) lightdegradation.

Distortion, excessive pitting, corrosion or other damageto fitting(s).

If provided, exposed red core yarn. However if damage ispresent and red yarns are not exposed DO NOT USE thesling.

Any conditions which cause doubt as to the strength ofthewebsling.

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SLINGS


A three-stage procedure is recommended to help ensure that web slings

are inspected with appropriate frequency:

Whenever a sling is initially received, it must be

inspected by a designated person to help ensure that the correct web

sling has been received and is undamaged and that the web sling meets

applicable requirements for its intended use.

The entire sling must be

Every sling must be inspected "periodically" by a

qualified and designated person. In order to validate the frequent level

of inspection, the periodic inspection should be performed by someone

other than the individual(s) who most commonly performs the frequent

inspection. The frequency of periodic inspections is based on the sling's

actual or expected frequency of use, severity of service conditions, the

nature of the work performed with the sling and experience gained

during the inspection of other slings used in similar circumstances.

General guidelines for the frequency of periodic inspections are:

Normal serviceyearly

Severe servicemonthly to quarterly

Special serviceas recommended by a qualified person

Periodic inspections intervals must not exceed one year.

Written records are not required for frequent inspections, butWSTDA

WS-1 or ASME B30.9 require that a written record of the most recent

periodic inspection be maintained. SeeWSTDAWS-1 or ASME B30.9 for

more information about definitions of Normal, Severe and Special

service conditions.

Initial Inspection

Frequent Inspection inspected before each

shift or day in Normal service and before each use in Severe service

applications.

Periodic Inspection

Environmental factors such as an exposure to sunlight, dirt or gritty-type

matter and cyclical changes in temperature and humidity, can result in

an accelerated deterioration of web slings. The rate of this deterioration

will vary with the level of exposure to these conditions and with the

thickness of the sling material. For example, single ply slings will

generally degrade more rapidly with this exposure than multiple ply

slings. Web slings that are used outdoors regularly should generally be

permanently removed from service within a period of 2 to 4 years. All

web slings that are exposed to these conditions should be highly

scrutinized during their inspections.

Visible indications of such deterioration can include the following:

Fading of webbing color.

Uneven or disoriented surface yarn of the webbing.

Shortening of the sling length.

Reduction in elasticity and strength of the sling material due to

an exposure to sunlight, often evident by an accelerated

abrasive damage to the surface yarn of the sling.

Breakage or damage to yarn fibers, often evident by a fuzzy

appearance of the web.

Stiffening of the web, which can become particularly evident

when web slings are exposed to outdoor conditions without

being used or cyclically tensioned.

You should always avoid any action that causes the types of damage

identified in the previous section of this Safety Bulletin, including (but

not limited to):

Dropping or dragging slings on the ground, floor or over

abrasive surfaces.

Pulling slings from under loads when the load is resting on the

slingplace blocks under load if feasible.

Shortening or adjusting sling using methods not approved by

the sling manufacturer or qualified person.

Twisting, kinking or knotting the sling.

Exposing slings to damaging acids or alkalis.

Exposing slings to sources of heat damage or weld spatter.

Using slings or allowing exposure to temperatures above 194F

(90C) or below -40F (-40C).

"Tip loading" a sling on a hook instead of centering it in the base

or "bowl" of the hook.

Using hooks, shackles or other hardware that have edges or

surfaces that could damage sling.

Running/driving over slings with a vehicle or other equipment.

Synthetic slings are affected by some chemicals ranging from little to

total degradation. Time, temperature and concentration factors affect

the degradation. For specific applications, consult the manufacturer. In

addition, water absorption can decrease the strength of nylon web

slings by as much as 1015% (its strength returns when the sling dries

completely). For specific applications, consult the manufacturer.

Synthetic web slings can be damaged, abraded or cut as tension and

compression between the sling, the connection points and the load

develops. Surfaces in contact with the sling do not have to be very

2c. How often to inspect slings

3b. Avoid actions that cause damage to slings

3c. Safeguard slings with sufficient protection

3a. Avoid environmental degradation

3. Slings Must be Adequately Protected from Damage

Cuts or tears Snags

Excessive abrasive wear

Holes/punctures Melting or charring Weld spatter

Acid/alkali burns Broken/worn stitches Crushed webbing Knots Embedded materials

UV degradation Exposed red core yarns

Table 2. Types of damage you should look and feel for in web slings

No UV Degradation

Faded From UV Exposure


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abrasive or have "razor" sharp edges in order to create the conditions for

sling failure. Therefore, web slings must ALWAYS

There are a variety of types of ways to protect slings from such damage.

A qualified person might select and use appropriate engineered

protectors/softenerscommercially available products (e.g., sleeves,

wear pads, edge wraps, body wraps, corner protectors, etc.) specifically

designed to protect slings from damage. A qualified person might also

design and construct their own methods of protection so long as the

sling is adequately protected from and/or kept off of the damaging edge

surface.

Regardless of the particular method chosen, the goal is to ensure that

the sling, under tension, maintains its ability to securely lift the load

while avoiding contact with damaging or abrasive surfaces under

tension. A qualified person must carefully consider the most appropriate

means to accomplish this goal. The protection used should not be

makeshift (i.e., selecting and using cardboard, work gloves or other such

items based solely on convenience or availability).

Regardless of the approach taken, a qualified person must ensure that

the protection method chosen is appropriate for the types of damage to

which the slings will be exposed. For instance, some protection provides

abrasion resistance, but offers virtually no protection against cuts.

Several "test" lifts, done in a non-consequence setting, may be necessary

to determine the suitability of the protection device(s). After each "test"

lift, the protection device(s) and sling(s) need to be inspected for

damage and suitability. You should keep in mind that no protection is

"cut proof" and you should always operate within the specified limits of

the sling and its accessories (e.g., fixtures, hardware, protection, etc.).

be protected from

being cut or damaged by corners, edges, protrusions or abrasive

surfaces with protection sufficient for the intended purpose.

When lifting loads, a trained, qualified and knowledgeable user must

take into account the factors and issues addressed in this bulletin, as well

as considering any other relevant factors not addressed herein (see Table

4). Among the factors related specifically to web slings, users must

perform several activities, including (but not limited to) those discussed

in the following subsections.

Determine the weight of the load and make sure it does not exceed

the sling's rated capacity or the capacity of any of the components of

the rigging system. Users must also determine the load's center of

gravity (CG) to make sure the rigging system used will be able to retain

and control the load once lifted.

Select a sling having suitable characteristics for the type, size and

weight of the load, the type of hitch (see Table 3) and the environment.

The sling must be securely attached to the load and rigged in a

manner to provide for load control to prevent slipping, sliding and/or

loss of the load. A trained, qualified and knowledgeable user must

determine the most appropriate method of rigging to help ensure a

safe lift and control of the load.

4a. Assess the load

4b. Select an appropriate sling/configuration

4. Always Use Slings Properly

Safe handling, lifting and manipulation of materials and loads requires consideration of a number of factors and issues, including

(but not limited to):

Categories Issues/ Factors to Consider

Wind

Weather

Visibility

Environmental temperature

Object temperature

Chemical conditions and exposure

Ground stability

Underground installations

Weight

Dimensions

Center of Gravity (CG)

Attachment point integrity

Susceptibility to crushing/compression

Loose parts that could fall from load

Combination loads

Damaging surfaces/edges

Single/multiple cranes/hoists

Maximum/planned operating radius

Allowable load

Ratio of lift to allowable load

Clearance to surrounding facilities

Power lines and other environmental hazards

Clearance between boom and lift

Emergency/contingency set down area

Equipment inspection

Ensure a clear load path

Sling selection

Load control

Lift point (over the CG)

Positive sling-to-load engagement

Appropriate hitch (for CG and load control)

Load is free to move and is not snagged

Coordination of multiple slings

Suitable wear protection

Sling capacity is adequate for

angle and tension

Area clear of unnecessary personnel Signals: Visual, audible, electronic, etc.

Personnel away from load and other dangers

Pre-lift plan and meeting

Tag lines/spotter requirements

Hitch Comments

Vertical

Hitch

Choker

Hitch

Basket

Hitch

Environment

Load

Equipment/Lift

Rigging

Personnel

Table 3. Common types of sling hitches

Table 4. Issues and Factors to consider when handling, lifting and manipulating materials and loads

Sling passes through one end around

the load and the other end is placed onthe hook. Rated capacity is normally 80%of that for a vertical hitch. Load control islimited with only one sling rigged in achoker hitch. Also, the choke pointshould always be on the sling bodynoton the sling eye, fitting, base of the eyeor fitting, splice or tag.

One end is placed on the hook, while the

other end is attached directly to the load.

A tagline should be used to prevent load

rotation.

The sling cradles the load while both

ends are attached overhead. The rated

capacity for a basket hitch is twice that

for a vertical hitch. As with the choker

hitch, more than one sling rigged in a

basket hitch (or some other means) may

be necessary to help ensure load control.


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SLINGS


Where to Find Additional Information

Synthetic Web Slings.

ASME B30.9Synthetic Webbing Slings: Selection, Use andMaintenance.

OSHA 29 CFR 1910.184Slings. Rigging handbooks.

OSHA Guidance on Safe Sling Use.

Manufacturers catalog, manual, website, bulletins, etc. Formal training provided by manufacturers or other outsideentities.

Angle A

in degrees

from horizontal

Tension

Multiplier

90 1.000

85 1.004

80 1.015

75 1.035

70 1.064

65 1.104

60 1.155

55 1.221

50 1.305

45 1.414

40 1.555

35 1.742

30 2.000

Angle of Choke

(degrees)Angle of Choke

Reduction

Factor= >or

slings safety use inspection

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