Rigging Failures and Crane Accidents: Identifying Liability

Rigging failures are one of the leading causes of crane accidents and dropped-load incidents on construction sites. When a sling breaks, a shackle fails, or a load shifts and falls, the results can be catastrophic. These cases often involve complex questions about who selected the rigging, who inspected it, and whether the rigging was appropriate for the load.

After 27 years of working with cranes and rigging systems, I have seen rigging failures caused by everything from corroded wire rope slings to improperly sized shackles to loads rigged without a proper lift plan. This article covers the most common types of rigging failures and how to establish liability in rigging-related crane accidents.

Understanding Rigging in Crane Operations

Rigging refers to the hardware and methods used to connect a load to a crane's hook. It includes:

• Slings -- wire rope, synthetic web, chain, or synthetic round slings used to wrap, choke, or basket the load
• Shackles -- U-shaped connectors used to join slings to the crane hook or to attachment points on the load
• Hooks -- the crane's main hook and any auxiliary hooks, with safety latches
• Spreader bars and lifting beams -- engineered devices used to distribute the load across multiple pick points
• Below-the-hook lifting devices -- specialized attachments designed for specific types of loads

Every component in the rigging system has a rated capacity. If any single component is overloaded, undersized, damaged, or improperly applied, the entire system can fail.

Common Types of Rigging Failures

1. Overloaded Slings

Sling capacity depends on the type of sling, the hitch configuration (vertical, choker, basket), and the sling angle. A common mistake is using a sling rated for a vertical hitch in a choker hitch, which reduces its capacity by 20-25%. Similarly, basket hitches at steep angles dramatically reduce capacity. Many riggers fail to account for these derating factors.

2. Damaged or Worn Slings

Wire rope slings deteriorate over time from use, abrasion, corrosion, and kinking. OSHA and ASME B30.9 establish specific removal criteria, including broken wires, kinking, crushing, bird-caging, corrosion, and heat damage. Slings that should have been removed from service are a frequent finding in rigging failure investigations.

3. Improper Hitch Configuration

The way a sling is attached to a load directly affects its capacity and the security of the connection. Common errors include:

• Choker hitches applied at the wrong angle
• Single-leg lifts on loads that require multi-point rigging
• Slings bearing on sharp edges without protection (softeners or edge guards)
• Improper basket hitch application allowing the load to slide

4. Shackle Failures

Shackle failures can occur when:

• The shackle is undersized for the load
• The pin is not fully seated or secured
• Side-loading exceeds the shackle's design limits
• The shackle has been modified, welded, or repaired without authorization

5. No Lift Plan

Critical lifts and complex rigging operations require a written lift plan that specifies the load weight, rigging configuration, sling types and sizes, hitch method, and lift sequence. When lifts proceed without a plan, the risk of rigging failure increases substantially because no one has verified that the rigging is adequate for the load.

Who Is Liable for Rigging Failures?

Rigging failure cases typically involve multiple parties with overlapping responsibilities:

1. The Rigger -- the person who selected and applied the rigging hardware is directly responsible for choosing the right equipment and applying it correctly. OSHA requires that riggers be qualified by training and experience.
2. The Crane Operator -- the operator has a duty to refuse to make a lift if the rigging appears unsafe. However, the operator is typically not responsible for selecting the rigging.
3. The Employer -- responsible for ensuring riggers are qualified, rigging hardware is inspected and maintained, and lift plans are prepared when required.
4. The General Contractor -- as the controlling entity, responsible for overall site safety and for ensuring that qualified personnel are performing rigging work.
5. The Rigging Hardware Manufacturer -- may be liable if a defect in the sling, shackle, or other hardware contributed to the failure.

Key Evidence in Rigging Failure Cases

• Failed rigging hardware -- the broken sling, shackle, or other component must be preserved for metallurgical analysis
• Load weight documentation -- shipping documents, manufacturer specifications, or calculated weights for the load being lifted
• Rigging inspection records -- documentation of sling inspections per ASME B30.9
• Lift plan -- if one existed, it should specify the rigging configuration. If none existed, that itself may be evidence of negligence.
• Training records -- the rigger's training and qualification documentation
• Purchase records -- when the rigging was purchased, from whom, and its rated capacity

OSHA and ASME Standards for Rigging

Several regulatory standards govern rigging in crane operations:

• OSHA 1926.251 -- Rigging equipment for material handling in construction
• OSHA 1926.1404 -- Assembly/disassembly rigging requirements
• OSHA 1926.1425 -- Keeping clear of the load
• ASME B30.9 -- Slings (the primary industry standard for sling inspection, use, and removal criteria)
• ASME B30.10 -- Hooks
• ASME B30.26 -- Rigging hardware (shackles, links, rings, turnbuckles, etc.)

For more on OSHA's crane-specific standards, see our article on OSHA crane safety standards for attorneys.

Get Expert Analysis for Your Rigging Case

Rigging failure cases require an expert who has hands-on experience selecting, inspecting, and applying rigging hardware in the field. With over 27 years of crane and rigging experience and NCCCO certifications, Matthew J. Stull provides thorough investigation and expert analysis for attorneys handling rigging-related crane accidents.

Call (570) 903-7119 or send a message to discuss your case.