Frequently Asked Questions

Have some questions? We can help! We've compiled our most frequently asked questions below ranging from lifting slings, rigging hardware, fall protection, wire rope slings, and more. If you can't find the answer you're looking for, contact us and we'll help you any way we can!

FAQ Categories

Twin-Path Extra Covermax Slings

Yes, A Twin-Path Sling can fit spaces half of their catalog width with no reduction in capacity

The Tell-Tails are overload indicators and will retract and eventually disappear if the sling is overloaded. The Fiber Optic determines if the interior core of the sling has suffered chemical, heat or crushing damage. If light does not pass from one end to the other, remove the sling from service and send to the manufacturer for repair evaluation.

Tell-Tails should extend past the tag area of each sling. If both Tell-Tails are not visible, remove the sling from service. Send the sling to the manufacturer for repair evaluation.

Slings used with fittings shall be compatible with the fittings used. The lifting capacity shall be rated at the lower of the sling or fitting. Fitting openings shall be of the proper shape and size to assure that the sling will seat properly.

Hydrocarbons and oils do not affect the performance of any Twin-Path sling.

G-Link Connectors can be used to shorten the length or reach of a synthetic sling.

At rated capacity, nylon slings will stretch up to 15%. Round slings made with polyester will stretch 3%. Braided Polyester slings will stretch 9%. Twin-Path Extra Slings w/ K-Spec core yarn stretch less than 1% at rated capacity.

NO! Roundslings that suffer damage to the load bearing cores must be removed from service. These slings shall be destroyed to prevent inadvertent use.

Yes. As part of our manufacturing process, each Twin-Path Extra Sling is proof tested to two times its vertical rated capacity. Every repaired Twin-Path Extra Sling is also proof tested before it is returned to the customer.

The word "sharp" is considered subjective and is no longer used in our catalog or website. Any material can be cut when exposed to enough pressure and a sharp edge. Diamonds, the hardest substance known, can be split into smaller parts by skilled cutters. CornerMax Pads must be utilized to protect the sling from all edges and corners. For an example, press your hand against the edge of a table. If you run your hand back and forth with some pressure applied, you'll realize that the edge doesn't need to be "sharp" to cut.

No. The technology that developed the CornerMax pad is for cut protection. Synthetic Armor pads are intended for abrasion protection or to increase the diameter of a bearing surface.

Abrasion protection is needed when the sling is wrapped around a load which is rough, dirty or gritty. Cut protection is needed when there is an edge or corner that the sling will come in contact with.

Wire Rope Slings

A single strand sling is less flexible than a multipart wire rope sling. Also, a multipart wire rope sling provides a better D/d ratio.

Up to 1-1/8", 6x25 IWRC. Over 1-1/8", 6x37 IWRC is used. T&D Ultra's are made from 7x19 GAC.

Gator-Max is handspliced, Gator-Laid is made using swaged sleeves.

Synthetic Slings

The differences are usually not a factor in most sling applications. At rated capacity, a treated nylon sling stretches approximately 7-10%, whereas a treated polyester sling will stretch approximately 3.5-5%. The extra stretch in nylon helps to avoid shock loading. Polyester’s smaller stretch factor makes load control easier by reducing bounce. In a chemical environment, nylon should not be used in acidic environments, including those where bleaching agents are present while polyester should not be used near various aldehydes.

Water has no significant affect on the strength of web slings. For questions on specific chemicals, please contact Bairstow @ or 800-241-8990

Yes, dirt in a web sling can promote internal abrasion that can reduce sling strength and possibly shorten sling life.

All slings determined to be a Bairstow sling can be retagged if it otherwise passes inspection and proof test loading, applicable inspection/testing fees will be charged.

The eye is simply a separated two part sling in itself, thus, there is no need for a two-ply eye on a two-ply sling. This same logic applies to higher ply fabricated web sling products.

A sling connects the crane hook to the load and is an import rigging tool. Slings can be made of steel wire rope, chains or synthetic man made fibers like polyester, nylon, K-spec or Kevlar. A synthetic sling is a sling made up of synthetic yarn like nylon, polyester or K-spec.

Synthetic slings made of man made high tenacity fibers have many advantages and conventional wire ropes and chains. Some of these are:

  • Very light and therefore easy to rig and handle.
  • Do not damage sensitive or delicate surfaces, therefore lower industrial wastage.
  • Are colour coded for ease of identification, therefore less chances of misuse.
  • Improve productivity and employee morale, therefore better labour relationships.
  • Do not rust or corrode and therefore do not weaken with age.
  • Easy visual inspection, saving frequent inspection and proof load costs.
  • Save storage costs as they are flexible and light and therefore easy to store.
  • Grips load tightly along the contours of the load.
  • Eliminates need for consumables like grease and hand gloves, therefore lower recurring costs.
  • Lower injuries to employees and riggers, therefore lower compensation claims.
  • Reduces machine downtime, in industries where dies or work rolls will have to be changed using slings.

The disadvantages if used improperly are:

  • Can be easily cut or damaged if used unprotected over sharp edges.
  • Can not be used in temperatures exceeding 80 degree Celsius.
  • Higher initial cost compared to conventional slings but pay back period is very quick.

Yes, however please call us and if after inspection and testing we find that the inner core yarns are not damaged, we will repair the sling at a very nominal cost.

The K-spec fiber is the "best" fiber in terms of high strength and very low stretch equivalent to steel. However it is also an expensive fiber. But for slings of capacity over 30 Metric Tones safe working load, there is no alternative to K-spec fiber. However, for slings of capacity from 1 MT to 30 MT, polyester and nylon are normally used. Polyester is a preferred fiber because it stretches much less than nylon and has much better resistance to chemicals and sunlight.

Steel Slings

Aside from personal preference, no. As the sling mfg., Bairstow warrants that all of our products are free from defects in materials and workmanship and adhere to all known engineering and manufacturing standards. Routine testing is performed on all of the materials we use to assure that you are getting only the highest quality products.

Yes, as of July 8, 2011, ASME and OSHA require legible identification markings on all wire rope slings.

The Flemish splice method tends to result in varying degrees of strand looping in the sling eye during fabrication and the amount of high stranding varies based on the base wire rope diameter. This condition is not a cause for removal from service as sling strength and durability are not affected. However, high strands in the sling BODY do affect sling strength and indicate that the sling has been damaged and should be removed from service immediately.

Yes, when used under the same conditions, chain slings can be expected to last longer than wire rope slings.

All grade 100 chain slings are approximately 25% stronger than grade 80 chain slings of the same diameter. The chain is harder, resulting in greater resistance to wear and, therefore, longer life. As of 2008, Bairstow offers grade 100 chain slings as our standard offering.

No. All used slings must be sent back to Bairstow for inspection and proof testing before it can be retagged and put back into service.

Welded chain slings are connected via permanent, welded connections making them “tamper proof”, this offers assurance you have an assembly which has not been compromised with an incompatible component. However, mechanical assemblies allow for quick and easy fabrication, as well as, repairs in the event of potential sling damage.

Chain and steel mesh slings can be repaired, along with, minor outer jacket damage on Twin Path and Single Path (with Tell Tail/Fiber Optics and/or the Check Fast Inspections system) high performance round slings. However, web slings, standard polyester round slings and wire rope slings cannot be repaired, but, their undamaged hardware can be reused in remanufactured assemblies.

Any of our high performance or polyester round slings can be made in excess of 100 ft. in length. For other types of slings the maximum length varies, please contact or 800-241-8990 for further details.

Rigging Hardware

Round Pin Shackles can be used in tie down, towing, suspension or lifting applications where the load is strictly applied in-line. Screw Pin Shackles can be used in any application where a round pin shackle is used. In addition, screw pin shackles can be used for applications involving side-loading circumstances. Reduced working load limits are required for side-loading applications. While in service, do not allow the screw pin to be rotated by a live line, such as a choker application. Bolt-Type Shackles can be used in any applications where round pin or screw pin shackles are used. In addition, they are recommended for permanent or long term installations and where the load may slide on the shackle pin causing the pin to rotate.

You should remove your hook from service if Remove if, there is any of the following:

  • Bending or twisting exceeding 10° from the plane of an unbent hook
  • Increase in throat opening exceeding 15 percent
  • Wear exceeds 10 percent of the original cross sectional dimension
  • Hook latch is inoperative or missing (where provided)
  • Cracks, nicks gouges
  • Damaged hook attachment or securing means
  • Manufacturer's identification is missing or not legible
  • Heat damaged or weld splattered
  • Other visible damage that causes doubt as to integrity of the hook

WLL is the abbreviation for Working Load Limit. It means the maximum allowable load that a piece of rigging equipment can safely lift, it is also sometimes called “rated load” or “rated capacity”.

Rigging users must be aware that the WLL of a piece of rigging may be reduced by several factors such as temperature, environment, angle of loading or type of hitch used.

This would depend on the style of hook being used, For a regular Single Point Hook it is recommended that a maximum of 2 slings are used on the hook, if the user needs to use more than 2 slings to lift the load then a collector ring such as a Link or Shackle should be used between the Hook and the Slings.

If the hook is a Duplex or Quad Hook (2 or 4 pointed) then the Hook points must be equally loaded to balance the forces on the Hook.

The ASME B30.26 standard says: Each turnbuckle, eyebolt, and eye nut shall be marked to show

  • name or trademark of manufacturer
  • size or rated load
  • grade for alloy eyebolts

So the WLL limit does not have to be marked on the Eyebolt if the size is, as the user you must make yourself aware of the WLL by referring to the manufacturers specification for the style, size and material of the Eyebolts you are using.

OSHA - Crane and Derrick Standard

A new OSHA standard for Cranes in Construction goes in to effect November 8, 2010. It requires operators of most cranes above 2,000 pounds capacity when used in construction to be either certified by an accredited crane operator testing organization or qualified through an audited employer program. It requires a "Qualified" rigger and signal person. See standard for exact details. A copy of the regulatory text is available at

The new OSHA standard says that a "qualified rigger" is someone who meets the definition of a qualified person. OSHA states that a "Qualified Person" is - a person who by possession of a recognized degree or certificate of professional standing, 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.

A qualified rigger is required during the assembly/disassembly of cranes, and when employees are engaged in hooking, unhooking or guiding the load, or in initial connection of a load to a component or structure and are within the fall zone.

The area (including but not limited to the area directly beneath the load) in which it is reasonably foreseeable that partially or completely suspended materials could fall in the event of an accident.

A copy of the regulatory text is available at

Employers must provide certification and /or qualification at no cost to the employee.

Yes. Crosby does offer a two-day Rigging Trainer Development course at no charge to full line Crosby Distributors and end users of our products. Day one is designed for those product users who need fundamentals of rigging only. Day two is designed for trainers or individuals that need more advanced information. Students who wish to attend day two must have attended the day one 24 hours prior. List of what successful day two attendees receive from Crosby: PowerPoint files provided by Crosby that can be utilized by end user trainers in their classroom training sessions for educating their employees on fundamentals of rigging while using Crosby rigging hardware in conjunction with slings. All day one attendees receive a certificate for attending the "Fundamentals of Rigging" class and successful day two attendees receive a certificate stating that they are authorized to use Crosby training materials for 48 months from date of issue. Successful day two attendees also receive a certificate stating they have earned 1.9 "CEUs" Authorization to purchase Crosby classroom training materials at discounted rates for their in-house rigging training needs. CD ROMs for computer based rigging training sessions. Those individuals who successfully complete a Crosby CD ROM computer based training program can request a Certificate of Achievement from Crosby for documentation of education achieved. CD ROM with PowerPoint files for 30 ? 45 minute refresher rigging training sessions. Note: Interested parties working in manufacturing or construction environments should request the ASME/OSHA Rigging Trainer Development Schedule from Crosby. If working in Land Based Oil or Gas environments please request the Land Based Rigging Trainer Development Schedule. If working in offshore environments, please request the API Rigging Trainer Development Schedule. Seminar schedules for the two-day Rigging Trainer Development courses can be downloaded from the Crosby website: Click onto "Training"and select "Seminar Schedule."

No! Crosby does not certify riggers. Certification normally requires passing a written and hands on practical exam administered by a third party. Crosby however does provide educational seminars that greatly help individuals in their endeavors to become a competent or qualified rigger. The time spent in our seminars and certificate of training received goes a long way in proving rigger qualifications when using Crosby rigging products in conjunction with slings. The education achieved can also prove useful in preparing for the written and practical exams to be a certified rigger. See information later in this memo on how to become a certified rigger. To request an "On Site" 4 or 8 hour Crosby seminar, please sign onto the Crosby website Click onto "Training" and select "Request for On Site Seminar". Proper paperwork must be submitted and reviewed by Crosby before training can be confirmed.

Yes! Please download the "Qualified Rigger Management Sign Off Authorization Form" below. Crosby's Qualified Rigger Management Sign Off Authorization Form

Normally one must pass a written and a practical "hands on" exam. The organizations below administer or offer rigger certification. NCCCO ? National Commission for the Certification of Crane Operators ? NCCER ? National Center for Construction Education and Research ? Contact ACRP (Association of Crane and Rigging Professionals) ? for other possible sources of testing. Note: Some cities, states or employers may have special requirements.

Crosby offers 4 and 8 hour rigging seminars at no charge for end users of our products. (Certain criteria must be met.) Crosby offers two-day Rigging Trainer Development courses at no charge in selective cities nationwide. Crosby provides all seminar attendees complete set of training materials at no charge. Crosby offers computer based rigging training programs via CD ROM. Beginning November 2010, all two-day seminar attendees will receive at no charge "prep" materials for the NCCCO Level I rigger exams. Crosby issues Certificate of Achievement to all seminar attendees. This certificate provides proof of attendance as a means to document one's education on the subject matter provided. Crosby has trained over 250,000 individuals since 1991. Most Crosby end user seminars are conducted by "certified" riggers. Special Note: Classroom training as provided by Crosby is only one element in becoming a qualified, competent, or certified rigger. Crosby strongly encourages that seminar attendees also obtain "hands on" training and appropriate on the job experience as well. See Crosby "Seminar Schedules" for list of two and three day Rigging Trainer Development courses offered in selective cities. See Crosby "Request On Site Training" to request a possible on site Crosby four hour or eight hour seminar.

By Phone: Primary contact is Julie Wilson at 918-834-4611 ext. 235 or secondary contact is Toni Vestal at ext. 357. Via E-mail: Seminar schedules for the two-day Rigging Trainer Development courses can be downloaded from the Crosby website at: