Regulations (Standards 29 cfr) Slings. 1910. 184



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Regulations (Standards - 29 CFR)

Slings. - 1910.184


1910.184(a)

Scope. This section applies to slings used in conjunction with other material handling equipment for the movement of material by hoisting, in employments covered by this part. The types of slings covered are those made from alloy steel chain, wire rope, metal mesh, natural or synthetic fiber rope (conventional three strand construction), and synthetic web (nylon, polyester, and polypropylene).


1910.184(b)

Definitions. Angle of loading is the inclination of a leg or branch of a sling measured from the horizontal or vertical plane as shown in Fig. N-184-5; provided that an angle of loading of five degrees or less from the vertical may be considered a vertical angle of loading.


Basket hitch is a sling configuration whereby the sling is passed under the load and has both ends, end attachments, eyes or handles on the hook or a single master link.
Braided wire rope is a wire rope formed by plaiting component wire ropes.
Bridle wire rope sling is a sling composed of multiple wire rope legs with the top ends gathered in a fitting that goes over the lifting hook.
Cable laid endless sling-mechanical joint is a wire rope sling made endless by joining the ends of a single length of cable laid rope with one or more metallic fittings.
Cable laid grommet-hand tucked is an endless wire rope sling made from one length of rope wrapped six times around a core formed by hand tucking the ends of the rope inside the six wraps.
Cable laid rope is a wire rope composed of six wire ropes wrapped around a fiber or wire rope core.
Cable laid rope sling-mechanical joint is a wire rope sling made from a cable laid rope with eyes fabricated by pressing or swaging one or more metal sleeves over the rope junction.
Choker hitch is a sling configuration with one end of the sling passing under the load and through an end attachment, handle or eye on the other end of the sling.
Coating is an elastomer or other suitable material applied to a sling or to a sling component to impart desirable properties.
Cross rod is a wire used to join spirals of metal mesh to form a complete fabric. (See Fig. N-184-2.)
Designated means selected or assigned by the employer or the employer's representative as being qualified to perform specific duties.
Equivalent entity is a person or organization (including an employer) which, by possession of equipment, technical knowledge and skills, can perform with equal competence the same repairs and tests as the person or organization with which it is equated.
Fabric (metal mesh) is the flexible portion of a metal mesh sling consisting of a series of transverse coils and cross rods.
Female handle (choker) is a handle with a handle eye and a slot of such dimension as to permit passage of a male handle thereby allowing the use of a metal mesh sling in a choker hitch. (See Fig. N-184-1.)
Handle is a terminal fitting to which metal mesh fabric is attached. (See Fig. N-184-1.)
Handle eye is an opening in a handle of a metal mesh sling shaped to accept a hook, shackle or other lifting device. (See Fig. N-184-1.)
Hitch is a sling configuration whereby the sling is fastened to an object or load, either directly to it or around it.
Link is a single ring of a chain.
Male handle (triangle) is a handle with a handle eye.
Master coupling link is an alloy steel welded coupling link used as an intermediate link to join alloy steel chain to master links. (See Fig. N-184-3.)
Master link or gathering ring is a forged or welded steel link used to support all members (legs) of an alloy steel chain sling or wire rope sling. (See Fig. N-184-3.)
Mechanical coupling link is a non-welded, mechanically closed steel link used to attach master links, hooks, etc., to alloy steel chain.
FIGURE N-184-1 METAL MESH SLING (TYPICAL) (For Figure N-184-1, Click Here)
FIGURE N-184-2 METAL MESH CONSTRUCTION (For Figure N-184-2, Click Here)
FIGURE N-184-3 MAJOR COMPONENTS OF A QUADRUPLE SLING (For Figure N-184-3, Click Here)
Proof load is the load applied in performance of a proof test.
Proof test is a nondestructive tension test performed by the sling manufacturer or an equivalent entity to verify construction and workmanship of a sling.
Rated capacity or working load limit is the maximum working load permitted by the provisions of this section.

Reach is the effective length of an alloy steel chain sling measured from the top bearing surface of the upper terminal component to the bottom bearing surface of the lower terminal component.


Selvage edge is the finished edge of synthetic webbing designed to prevent unraveling.
Sling is an assembly which connects the load to the material handling equipment.
Sling manufacturer is a person or organization that assembles sling components into their final form for sale to users.
Spiral is a single transverse coil that is the basic element from which metal mesh is fabricated. (See Fig. N-184-2.)
Strand laid endless sling-mechanical joint is a wire rope sling made endless from one length of rope with the ends joined by one or more metallic fittings.
Strand laid grommet-hand tucked is an endless wire rope sling made from one length of strand wrapped six times around a core formed by hand tucking the ends of the strand inside the six wraps.
Strand laid rope is a wire rope made with strands (usually six or eight) wrapped around a fiber core, wire strand core, or independent wire rope core (IWRC).
Vertical hitch is a method of supporting a load by a single, vertical part or leg of the sling. (See Fig. N-184-4.)

1910.184(c)

Safe operating practices. Whenever any sling is used, the following practices shall be observed:

1910.184(c)(1)

Slings that are damaged or defective shall not be used.

1910.184(c)(2)

Slings shall not be shortened with knots or bolts or other makeshift devices.

1910.184(c)(3)

Sling legs shall not be kinked.

1910.184(c)(4)

Slings shall not be loaded in excess of their rated capacities.

1910.184(c)(5)

1910.184(c)(5)

Slings used in a basket hitch shall have the loads balanced to prevent

slippage.

1910.184(c)(6)

Slings shall be securely attached to their loads.

1910.184(c)(7)

Slings shall be padded or protected from the sharp edges of their loads

1910.184(c)(8)

Suspended loads shall be kept clear of all obstructions.

1910.184(c)(9)

All employees shall be kept clear of loads about to be lifted and of suspended loads.

1910.184(c)(10)

Hands or fingers shall not be placed between the sling and its load while the sling is being tightened around the load.

1910.184(c)(11)

Shock loading is prohibited.

1910.184(c)(12)

A sling shall not be pulled from under a load when the load is resting on the sling.

..1910.184(d)

1910.184(d)

Inspections. Each day before being used, the sling and all fastenings and attachments shall be inspected for damage or defects by a competent person designated by the employer. Additional inspections shall be performed during sling use, where service conditions warrant. Damaged or defective slings shall be immediately removed from service.

1910.184(e)

Alloy steel chain slings.

1910.184(e)(1)

Sling identification. Alloy steel chain slings shall have permanently affixed durable identification stating size, grade, rated capacity, and reach.

1910.184(e)(2)

Attachments.

1910.184(e)(2)(i)

Hooks, rings, oblong links, pear shaped links, welded or mechanical coupling links or other attachments shall have a rated capacity at least equal to that of the alloy steel chain with which they are used or the sling shall not be used in excess of the rated capacity of the weakest component.

1910.184(e)(2)(ii)

Makeshift links or fasteners formed from bolts or rods, or other such attachments, shall not be used.

1910.184(e)(3)

Inspections.

1910.184(e)(3)(i)

In addition to the inspection required by paragraph (d) of this section, a thorough periodic inspection of alloy steel chain slings in use shall be made on a regular basis, to be determined on the basis of (A) frequency of sling use; (B) severity of service conditions; (C) nature of lifts being made; and (D) experience gained on the service life of slings used in similar circumstances. Such inspections shall in no event be at intervals greater than once every 12 months.

..1910.184(e)(3)(ii)

1910.184(e)(3)(ii)

The employer shall make and maintain a record of the most recent month in which each alloy steel chain sling was thoroughly inspected, and shall make such record available for examination.

1910.184(e)(3)(iii)

The thorough inspection of alloy steel chain slings shall be performed by a competent person designated by the employer, and shall include a thorough inspection for wear, defective welds, deformation and increase in length. Where such defects or deterioration are present, the sling shall be immediately removed from service.

1910.184(e)(4)

Proof testing. The employer shall ensure that before use, each new, repaired, or reconditioned alloy steel chain sling, including all welded components in the sling assembly, shall be proof tested by the sling manufacturer or equivalent entity, in accordance with paragraph 5.2 of the American Society of Testing and Materials Specification A391-65, which is incorporated by reference as specified in Sec. 1910.6 (ANSI G61.1-1968). The employer shall retain a certificate of the proof test and shall make it available for examination.

1910.184(e)(5)

Sling use. Alloy steel chain slings shall not be used with loads in excess of the rated capacities prescribed in Table N-184-1. Slings not included in this table shall be used only in accordance with the manufacturer's recommendations.

..1910.184(e)(6)

1910.184(e)(6)

Safe operating temperatures. Alloy steel chain slings shall be permanently removed from service if they are heated above 1000 deg. F. When exposed to service temperatures in excess of 600 deg. F, maximum working load limits permitted in Table N-184-1 shall be reduced in accordance with the chain or sling manufacturer's recommendations.

1910.184(e)(7)

Repairing and reconditioning alloy steel chain slings.

1910.184(e)(7)(i)

Worn or damaged alloy steel chain slings or attachments shall not be used until repaired. When welding or heat testing is performed, slings shall not be used unless repaired, reconditioned and proof tested by the sling manufacturer or an equivalent entity.

1910.184(e)(7)(ii)

Mechanical coupling links or low carbon steel repair links shall not be used to repair broken lengths of chain.

1910.184(e)(8)

Effects of wear. If the chain size at any point of any link is less than that stated in Table N-184-2, the sling shall be removed from service.

1910.184(e)(9)

Deformed attachments.

1910.184(e)(9)(i)

Alloy steel chain slings with cracked or deformed master links, coupling links or other components shall be removed from service.

TABLE N-184-1 -- RATED CAPACITY (WORKING LOAD LIMIT), FOR ALLOY STEEL

CHAIN SLINGS

Rated Capacity (Working Load Limit), Pounds

[Horizontal angles shown in parentheses]

Chain size, inches Single branch sling -- 90º loading Double sling

vertical angle (1)Triple and quadruple sling (3)vertical angle (1)30º

(60º)45º

(45º)60º


(30º)30º

(60º)45º


(45º)60º

(30º)


1/43,2505,6504,5503,2508,4006,8004,900

3/86,60011,4009,3006,60017,00014,0009,900

1/211,25019,50015,90011,25029,00024,00017,000

5/816,50028,50023,30016,50043,00035,00024,500

3/423,00039,80032,50023,00059,50048,50034,500

7/828,75049,80040,60028,75074,50061,00043,000

138,75067,1005,80038,750101,00082,00058,000

1 1/844,50077,00063,00044,500115,50094,50066,500

1 1/457,50099,50061,00057,500149,000121,50086,000

1 3/867,000116,00094,00067,000174,000141,000100,500

1 1/280,000138,000112,90080,000207,000169,000119,500

1 3/4100,000172,000140,000100,000258,000210,000150,000

(1) Rating of multileg slings adjusted for angle of loading measured as the included angle between the inclined leg and the vertical as shown in Figure N-184-5.

(2) Rating of multileg slings adjusted for angle of loading between the inclined leg and the horizontal plane of the load, as shown in Figure N-184-5.

(3) Quadruple sling rating is same as triple sling because normal lifting practice may not distribute load uniformly to all 4 legs.
TABLE N-184-2. - MINIMUM ALLOWABLE CHAIN SIZE AT ANY POINT OF LINK

Chain size,

inches

Minimum allowable chain



size, inches

1/413/64


3/819/64

1/225/64


5/831/64

3/419/32


7/845/64

113/16


1 1/829/32

1 1/41


1 3/81 3/32

1 1/21 3/16

1 3/41 13/32

1910.184(e)(9)(ii)

Slings shall be removed from service if hooks are cracked, have been opened more than 15 percent of the normal throat opening measured at the narrowest point or twisted more than 10 degrees from the plane of the unbent hook.

..1910.184(f)

1910.184(f)

Wire rope slings.

1910.184(f)(1)

Sling use. Wire rope slings shall not be used with loads in excess of the rated capacities shown in Tables N-184-3 through N-184-14. Slings not included in these tables shall be used only in accordance with the manufacturer's recommendations.

1910.184(f)(2)

Minimum sling lengths.

1910.184(f)(2)(i)

Cable laid and 6x19 and 6x37 slings shall have a minimum clear length of wire rope 10 times the component rope diameter between splices, sleeves or end fittings.

1910.184(f)(2)(ii)

Braided slings shall have a minimum clear length of wire rope 40 times the component rope diameter between the loops or end fittings.

1910.184(f)(2)(iii)

Cable laid grommets, strand laid grommets and endless slings shall have a minimum circumferential length of 96 times their body diameter.

1910.184(f)(3)

Safe operating temperatures. Fiber core wire rope slings of all grades shall be permanently removed from service if they are exposed to temperatures in excess of 200 deg. F. When nonfiber core wire rope slings of any grade are used at temperatures above 400 deg. F or below minus 60 deg. F, recommendations of the sling manufacturer regarding use at that temperature shall be followed.

1910.184(f)(4)

End attachments.

1910.184(f)(4)(i)

Welding of end attachments, except covers to thimbles, shall be performed prior to the assembly of the sling.

..1910.184(f)(4)(ii)

1910.184(f)(4)(ii)

All welded end attachments shall not be used unless proof tested by the manufacturer or equivalent entity at twice their rated capacity prior to initial use. The employer shall retain a certificate of the proof test, and make it available for examination.
TABLE N-184-3. - RATED CAPACITIES FOR SINGLE LEG SLINGS
6x19 and 6x37 Classification Improved Plow Steel Grade Rope

With Fiber Core (FC)

___________________________________________________________

| |


Rope | Rated capacities, tons (2,000 lb) |

_________________|_________________________________________|

|| | |

Dia || Vertical | Choker |



(inches| Constr |____________________|____________________|

|| | | | | | |

|| HT | MS | S | HT | MS | S |

_______|________|______|______|______|______|______|______|

|| | | | | | |

1/4 | 6x19 | 0.49 | 0.51 | 0.55 | 0.37 | 0.38 | 0.41 |

5/16 | 6x19 | 0.76 | 0.79 | 0.85 | 0.57 | 0.59 | 0.64 |

3/8 | 6x19 | 1.1 | 1.1 | 1.2 | 0.80 | 0.85 | 0.91 |

7/16 | 6x19 | 1.4 | 1.5 | 1.6 | 1.1 | 1.1 | 1.2 |

1/2 | 6x19 | 1.8 | 2.0 | 2.1 | 1.4 | 1.5 | 12.6 |

9/16 | 6x19 | 2.3 | 2.5 | 2.7 | 1.7 | 1.9 | 2.0 |

5/8 | 6x19 | 2.8 | 3.1 | 3.3 | 2.1 | 2.3 | 2.5 |

3/4 | 6x19 | 3.9 | 4.4 | 4.8 | 2.9 | 3.3 | 3.6 |

7/8 | 6x19 | 5.1 | 5.9 | 6.4 | 3.9 | 4.5 | 4.8 |

1 | 6x19 | 6.7 | 7.7 | 8.4 | 5.0 | 5.8 | 6.3 |

1 1/8 | 6x19 | 8.4 | 9.5 | 10.0 | 6.3 | 7.1 | 7.9 |

1 1/4 | 6x37 | 9.8 | 11.0 | 12.0 | 7.4 | 8.3 | 9.2 |

1 3/8 | 6x37 | 12.0 | 13.0 | 15.0 | 8.9 | 10.0 | 11.0 |

1 1/2 | 6x37 | 14.0 | 16.0 | 15.0 | 10.0 | 12.0 | 13.0 |

1 5/8 | 6x37 | 16.0 | 18.0 | 21.0 | 12.0 | 14.0 | 15.0 |

1 3/4 | 6x37 | 19.0 | 21.0 | 24.0 | 14.0 | 16.0 | 18.0 |

2 | 6x37 | 25.0 | 28.0 | 31.0 | 18.0 | 21.0 | 23.0 |

_______|________|______|______|______|______|______|______|
TABLE N-184-3. - RATED CAPACITIES FOR SINGLE LEG SLINGS

6x19 and 6x37 Classification Improved Plow Steel Grade Rope

With Fiber Core (FC)

_____________________________________________________

|

Rope | Rated capacities, tons (2,000 lb)



_________________|___________________________________

||

Dia || Vertical Basket(1)



(inches| Constr |___________________________________

|| | |


|| HT | MS | S

_______|________|______|______|_____________________

|| | |

1/4 | 6x19 | 0.99 | 1.0 | 1.1



5/16 | 6x19 | 1.5 | 1.6 | 1.7

3/8 | 6x19 | 2.1 | 2.2 | 2.4

7/16 | 6x19 | 2.9 | 3.0 | 3.3

1/2 | 6x19 | 3.7 | 3.9 | 4.3

9/16 | 6x19 | 4.6 | 5.0 | 5.4

5/8 | 6x19 | 5.6 | 6.2 | 6.7

3/4 | 6x19 | 7.8 | 8.8 | 9.5

7/8 | 6x19 | 10.0 | 12.0 | 13.0

1 | 6x19 | 13.0 | 15.0 | 17.0

1 1/8 | 6x19 | 17.0 | 19.0 | 21.0

1 1/4 | 6x37 | 20.0 | 22.0 | 25.0

1 3/8 | 6x37 | 24.0 | 27.0 | 30.0

1 1/2 | 6x37 | 28.0 | 32.0 | 35.0

1 5/8 | 6x37 | 33.0 | 27.0 | 41.0

1 3/4 | 6x37 | 38.0 | 43.0 | 48.0

2 | 6x37 | 49.0 | 55.0 | 62.0

_______|________|______|______|__________________

HT = Hand Tucked Splice and Hidden Tuck Splice.

For hidden tuck splice (IWRC) use values in HT columns.

MS = Mechanical Splice.

S = Swaged or Zinc Poured Socket.

Footnote(1) These values only apply when the D/d ratio for HT slings is 10 or greater, and for MS and S slings is 20 or greater where: D=Diameter of curvature around which the body of the sling is bent; d=Diameter of rope.


TABLE N-184-4. - RATED CAPACITIES FOR SINGLE LEG SLINGS

6x19 and 6x37 Classification Improved Plow Steel Grade Rope

With Independent Wire Rope Core (IWRC)

___________________________________________________________

| |

Rope | Rated capacities, tons (2,000 lb) |



________________|_________________________________________|

|| | |


Dia || Vertical | Choker |

(inches| Constr |____________________|____________________|

|| | | | | | |

|| HT | MS | S | HT | MS | S |

_______|________|______|______|______|______|______|______|

|| | | | | | |

1/4 | 6x19 | 0.53 | 0.56 | 0.59 | 0.40 | 0.42 | 0.44 |

5/16 | 6x19 | 0.81 | 0.87 | 0.92 | 0.61 | 0.65 | 0.69 |

3/8 | 6x19 | 1.1 | 1.2 | 1.3 | 0.86 | 0.93 | 0.98 |

7/16 | 6x19 | 1.5 | 1.7 | 1.8 | 1.2 | 1.3 | 1.3 |

1/2 | 6x19 | 2.0 | 2.2 | 2.3 | 1.5 | 1.6 | 1.7 |

9/16 | 6x19 | 2.5 | 2.7 | 2.9 | 1.8 | 2.1 | 2.2 |

5/8 | 6x19 | 3.0 | 3.4 | 3.6 | 2.2 | 2.5 | 2.7 |

3/4 | 6x19 | 4.2 | 4.9 | 5.1 | 3.1 | 3.6 | 3.8 |

7/8 | 6x19 | 5.5 | 6.6 | 6.9 | 4.1 | 4.9 | 5.2 |

1 | 6x19 | 7.2 | 8.5 | 9.0 | 5.4 | 6.4 | 6.7 |

1 1/8 | 6x19 | 9.0 | 10.0 | 11.0 | 6.8 | 7.8 | 8.5 |

1 1/4 | 6x37 | 10.0 | 12.0 | 13.0 | 7.9 | 9.2 | 9.9 |

1 3/8 | 6x37 | 13.0 | 15.0 | 16.0 | 9.6 | 11.0 | 12.0 |

1 1/2 | 6x37 | 15.0 | 17.0 | 19.0 | 11.0 | 13.0 | 14.0 |

1 5/8 | 6x37 | 18.0 | 20.0 | 22.0 | 13.0 | 15.0 | 17.0 |

1 3/4 | 6x37 | 20.0 | 24.0 | 26.0 | 15.0 | 18.0 | 19.0 |

2 | 6x37 | 26.0 | 30.0 | 33.0 | 20.0 | 23.0 | 25.0 |

_______|________|______|______|______|______|______|______|


TABLE N-184-4. - RATED CAPACITIES FOR SINGLE LEG SLINGS

6x19 and 6x37 Classification Improved Plow Steel Grade Rope

With Independent Wire Rope Core (IWRC)

_____________________________________________________

|

Rope | Rated capacities, tons (2,000 lb)



_________________|___________________________________

||

Dia || Vertical Basket(1)



(inches| Constr |___________________________________

|| | |


|| HT | MS | S

_______|________|______|______|_____________________

|| | |

1/4 | 6x19 | 1.0 | 1.1 | 1.2



5/16 | 6x19 | 1.6 | 1.7 | 1.8

3/8 | 6x19 | 2.3 | 2.5 | 2.6

7/16 | 6x19 | 3.1 | 3.4 | 3.5

1/2 | 6x19 | 3.9 | 4.4 | 4.6

9/16 | 6x19 | 4.9 | 5.5 | 5.8

5/8 | 6x19 | 6.0 | 6.8 | 7.2

3/4 | 6x19 | 8.4 | 9.7 | 10.0

7/8 | 6x19 | 11.0 | 13.0 | 14.0

1 | 6x19 | 14.0 | 17.0 | 18.0

1 1/8 | 6x19 | 18.0 | 21.0 | 23.0

1 1/4 | 6x37 | 21.0 | 24.0 | 26.0

1 3/8 | 6x37 | 25.0 | 29.0 | 32.0

1 1/2 | 6x37 | 30.0 | 35.0 | 38.0

1 5/8 | 6x37 | 35.0 | 41.0 | 44.0

1 3/4 | 6x37 | 41.0 | 47.0 | 51.0

2 | 6x37 | 53.0 | 61.0 | 66.0

_______|________|______|______|__________________
HT = Hand Tucked Splice. For hidden tuck splice

(IWRC) use Table 1 values in HT column.

MS = Mechanical Splice.

S = Swaged or Zinc Poured Socket.


Footnote(1) These values only apply when the D/d ratio for HT slings is 10 or greater, and for MS and S slings is 20 or greater where: D=Diameter of curvature around which the body of the sling is bent; d=Diameter of rope.
TABLE N-184-5. -- RATED CAPACITIES FOR SINGLE LEG SLINGS

Cable Laid Rope -- Mechanical Splice Only

7x7x7 & 7X19 Constructions Galvanized Aircraft Grade Rope

7x6x19 IWRC Construction Improved Plow Steel Grade Rope

________________________________________________________

|

Rope | Rated capacities, tons (2,000 lb)



___________________________|_________________________________

| | ||


Dia | Constr | Vertical | Choker | Vertical

(inches) | | || basket(1)

________ __|_______________|__________|________|_____________

| | ||


1/4........| 7x7x7.........| 0.50 | 0.38 | 1.0

3/8........| 7x7x7.........| 1.1 | 0.81 | 2.0

1/2........| 7x7x7.........| 1.8 | 1.4 | 3.7

5/8........| 7x7x7.........| 2.8 | 2.1 | 5.5

3/4........| 7x7x7.........| 3.8 | 2.9 | 7.6

5/8........| 7x7x19........| 2.9 | 2.2 | 5.8

3/4........| 7x7x19........| 4.1 | 3.0 | 8.1

7/8........| 7x7x19........| 5.4 | 4.0 | 11.0

1..........| 7x7x19........| 6.9 | 5.1 | 14.0

1 1/8......| 7x7x19........| 8.2 | 6.2 | 16.0

1 1/4......| 7x7x19........| 9.9 | 7.4 | 20.0

3/4........| 7x6x19 IWRC...| 3.8 | 2.8 | 7.6

7/8........| 7x6x19 IWRC...| 5.0 | 3.8 | 10.0

1..........| 7x6x19 IWRC...| 6.4 | 4.8 | 13.0

1 1/8......| 7x6x19 IWRC...| 7.7 | 5.8 | 15.0

1 1/4......| 7x6x19 IWRC...| 9.2 | 6.9 | 18.0


1 5/16.....| 7x6x19 IWRC...| 10.0 | 7.5 | 20.0

1 3/8......| 7x6x19 IWRC...| 11.0 | 8.2 | 22.0

1 1/2......| 7x6x19 IWRC...| 13.0 | 9.6 | 26.0

| | ||


_____ _____|_______________|__________|________|_____________

Footnote(1) These values only apply when the D/d ratio is 10 or greater where:

D=Diameter of curvature around which the body of the sling is bent; d=Diameter of rope.



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