ASME B30.9 Slings: Inspection Tiers, Removal Criteria, and Records

The ASME B30.9 sling inspection requirements set three tiers of review: an initial inspection of every new or repaired sling before first use, a frequent visual inspection performed by a competent person each day or shift the sling is used, and a periodic inspection at least once every twelve months performed by a designated person and documented in writing. Slings that meet any of the standard’s damage criteria must be pulled from service on the spot, not at the end of the shift.

How the Standard Fits With OSHA

ASME B30.9 is a voluntary consensus standard. The enforceable federal rules for slings are OSHA’s 29 CFR 1910.184 for general industry and 29 CFR 1926.251 for construction. OSHA has issued guidance stating that it accepts slings manufactured and marked in accordance with ASME B30.9 under its de minimis policy, provided the ASME specifications do not lessen employee safety.¹ A de minimis violation carries no penalty and requires no correction, so meeting ASME B30.9 generally satisfies OSHA.

Where the two documents differ, the stricter figure controls for anyone under OSHA jurisdiction. Synthetic web sling temperature is the clearest example: ASME B30.9 permits use up to 194°F, while OSHA caps polyester and nylon at 180°F.² Serious OSHA violations for sling deficiencies carry penalties of up to $16,550 per violation, with willful or repeated violations reaching $165,514, adjusted annually for inflation.³

The Three Inspection Tiers

Initial Inspection

Every new sling and every repaired sling must be inspected before it is first used. This check confirms the sling matches its documentation: rated load, proper labeling, correct fittings, and no damage from shipping or the repair process itself. Manufacturing defects and transit damage caught here never reach a load.

Frequent Inspection

A competent person performs a visual check each day the sling is used, or before each shift in multi-shift operations. OSHA defines a competent person as someone capable of identifying existing and predictable hazards and authorized to take prompt corrective action.⁴ In practice, this is usually the rigger who is about to use the sling.

Frequent inspection focuses on obvious damage the rigger can see without disassembly: cuts, burns, crushed areas, broken wires, distorted fittings, and missing or unreadable identification. No written record is required, but the sling cannot be used if anything looks wrong. If the rigger has doubt, the sling comes out of service until a qualified person evaluates it.

Periodic Inspection

At least once every twelve months, a designated person with the expertise to evaluate the sling against the standard’s removal criteria performs a thorough inspection. Any deficiency found during a periodic inspection must be examined by a qualified person, who determines whether the sling can continue in service.⁵

Twelve months is a ceiling, not a target. Slings in severe service — heavy daily use, elevated heat, corrosive chemicals, abrasive loads — should be inspected more often. Monthly or quarterly intervals are common in demanding environments, and shortening the cycle is the employer’s call.

Written records of the most recent periodic inspection are required and must identify the specific sling and the date of the review.² The standard sets no minimum retention period beyond the most recent record, but many facilities keep records for the full service life of the sling because auditors and insurers expect it.

Removal From Service: What to Look For

A sling that meets any removal criterion comes out immediately. Some triggers apply to every sling type: missing or illegible identification, evidence of heat damage, and any visible condition that raises doubt about safe continued use. The rest depend on the material.

Alloy Steel Chain Slings

Retire the chain sling for any of the following:

Cracked, broken, or stretched links. These must be replaced, not repaired.
Wear that reduces link thickness below the minimum values in ASME B30.9 Table 9-1.9.5-1.
Bent, twisted, or stretched links or fittings.
Excessive corrosion or pitting, which weakens the load path even when the chain looks structurally intact.
Loss of articulation — links or fittings that no longer hinge freely.
Weld splatter, which creates stress concentrations at the link surface.
Heat damage. Under OSHA, a chain sling heated above 1,000°F must be permanently retired, and chains exposed above 600°F require reduced working load limits per the manufacturer’s recommendations.²

The standard also directs inspectors to check hooks against ASME B30.10 and other rigging hardware against ASME B30.26.⁵

Wire Rope Slings

Wire rope hides damage that other materials show plainly. Remove the sling for:

Ten or more randomly distributed broken wires in one rope lay, or five broken wires in one strand in one rope lay. For six-part braided slings, 20 broken wires per braid; for eight-part braided slings, 40 per braid.
Kinking, crushing, or bird-caging, where the outer strands bulge away from the core.
Severe localized abrasion that has worn through outer wires or reduced rope diameter.
Cracked, deformed, or excessively worn end fittings.
Severe corrosion on the rope body, end attachments, or fittings.

A knot anywhere in the sling body permanently disqualifies it. Knots reduce breaking strength dramatically, and there is no method to restore the rope to its rated capacity afterward.⁵

Synthetic Web Slings

Synthetic webbing is unforgiving because once the fibers are compromised, remaining strength cannot be reliably assessed. Immediate removal is required for:

Acid or caustic burns. Chemical exposure can weaken fibers even when the surface looks intact.
Melting or charring of the sling surface.
Snags, punctures, tears, or cuts, however small.
Broken or worn stitches, which hold spliced eyes and folded layers together.
Distorted end fittings.

OSHA applies the same criteria.² ASME B30.9 adds that load-bearing splices on synthetic web slings cannot be repaired; if the splice fails, the sling is scrap.⁵

Roundslings and Synthetic Rope Slings

Polyester roundslings and high-performance fiber roundslings share most of the synthetic web criteria, with one critical difference: core yarn repairs are prohibited entirely. If the outer jacket is damaged enough to expose or compromise the internal load-bearing yarns, the roundsling must be destroyed.⁵ OSHA goes further for fiber rope slings specifically and prohibits the use of any repaired or reconditioned fiber rope sling.²

Identification and Tags

Every sling must carry a permanent identifier that stays legible throughout its service life. At minimum, the marking must include the manufacturer’s name or trademark, the rated loads for the applicable hitch configurations (vertical, choker, and basket), the sling size, the number of legs if more than one, and the material type.⁵ Material type matters because it tells the operator the chemical and thermal limits before a load is rigged.

A sling with a missing or illegible tag is out of service. Under ASME B30.9, replacing identification is classified as a repair, which means only the original manufacturer or a qualified person can re-tag the sling, and the entity performing the work must mark the sling to identify itself.⁵ Protecting tags from abrasion, chemicals, and heat throughout the sling’s life avoids the disruption of an emergency re-tag.

Repair and Return to Service

Not every deficiency ends in retirement. Chain, wire rope, metal mesh, and synthetic web slings can be repaired, but only by the original manufacturer or an equivalent entity. OSHA defines an equivalent entity as a person or organization with the equipment, technical knowledge, and skills to perform the same repairs and tests as the manufacturer.² A shop with a welder does not qualify.

Proof testing is required after most repairs. Synthetic webbing slings must be proof tested to twice the rated capacity before returning to service.² Alloy steel chain slings that have been welded or heat-treated must be proof tested by the manufacturer or equivalent entity before reuse. Every repaired sling must be permanently marked or tagged with the date and nature of the repair and the identity of the entity that performed the work.

Hard limits exist. Cracked, broken, stretched, or twisted chain links are replaced, not repaired. Load-bearing splices on synthetic webbing cannot be repaired. Core yarns in polyester and high-performance roundslings cannot be repaired. Fiber rope slings cannot be repaired or reconditioned at all under OSHA rules. When the answer is unclear, retirement is the safer choice.

Temperature and Environmental Limits That Trigger Inspection

Service conditions drive many inspection findings. Synthetic web slings and polyester roundslings are rated to a maximum of 194°F under ASME B30.9.⁶ OSHA sets a stricter 180°F ceiling for polyester and nylon web slings.² For OSHA-regulated employers, 180°F is the working number.

Wire rope slings with an independent wire rope core are rated to 400°F under ASME B30.9.⁶ Above that, follow the manufacturer’s recommendations. Fiber-core wire rope slings tolerate less heat and require manufacturer guidance at any elevated temperature. Alloy steel chain requires reduced load limits above 600°F and permanent retirement above 1,000°F.² Non-impregnated metal mesh slings operate up to 550°F without a capacity reduction.

Cold matters too. ASME B30.9 sets a lower limit of −40°F for synthetic web slings, wire rope slings with an IWRC, and alloy steel chain slings.⁶ Below these thresholds, materials become brittle and failure modes change. Manufacturer consultation is required before use outside the rated temperature range.

Chemical exposure is a separate inspection driver. Strong acids, caustics, and oxidizing agents can degrade synthetic fibers internally without leaving obvious surface damage. Metal slings resist most chemicals but are not immune, and corrosive vapors weaken alloy steel over time. The standard requires operators to consult the manufacturer before using slings in any chemically active environment.

Storage counts as service in inspection terms. Slings should be kept clean, dry, and away from direct sunlight, chemicals, and heat sources. UV exposure degrades synthetic fibers even when the sling is idle, and storing wet wire rope slings accelerates internal corrosion.⁵

Records to Keep

Documentation is thin under the standard but non-negotiable where it exists. Frequent inspections do not require records. Initial inspections and periodic inspections do. The record must identify the specific sling and the date of the most recent periodic inspection.² Repair records travel with the sling on its permanent marking, showing the date and nature of the repair and the entity that performed it. That combination — a current periodic inspection record on file and a legible identification tag on the sling — is what an OSHA inspector or an insurance auditor will ask to see first.

1
Occupational Safety and Health Administration. Guidance on Safe Sling Use
2
Occupational Safety and Health Administration. 29 CFR 1910.184 – Slings
3
Occupational Safety and Health Administration. OSHA Penalties
4
Occupational Safety and Health Administration. Competent Person
5
The American Society of Mechanical Engineers. ASME B30.9-2021 Safety Standard for Cableways, Cranes, Derricks, Hoists, Hooks, Jacks, and Slings
6
Hanford Site. Hanford Site Hoisting and Rigging Manual – Chapter 2-9 Slings