Proof load testing to 250,000 lbs in our Hatfield shop, and to 10 tons anywhere in the country with the mobile unit. Static proof tests, and cycle testing run for as long and as many cycles as your specification calls for. Every certificate tied to a serial number.
Proof testing is not optional for as much rigging as people think. OSHA requires it outright in four places, and every one of them says it has to be done by "the manufacturer or equivalent entity."
That phrase, manufacturer or equivalent entity, is the one that matters. We fabricate wire rope and chain slings in the same building the test bed sits in, which puts us on the right side of it without an argument.
Two options, and which one you need is usually decided by the capacity rather than the location.
125 tons. This covers the overwhelming majority of slings, master links, shackles and below-the-hook devices in normal industrial service, at any multiple of rated capacity the standard calls for.
20,000 lbs on the mobile unit, which goes wherever it needs to. The right answer when the equipment cannot practically leave your facility.
A single static proof hold, or repeated cycles run to a duration and count you specify. See the next section.
Hoists, shackles and smaller assemblies make up most of the work, along with the slings we build. If you have something unusual, the question worth asking is not whether we will test it but whether it fits the bed and the capacity, and that is a short phone call.
Testing is billed at the same hourly rate as inspection, which makes it straightforward to combine the two on one visit.
Most shops will give you a single proof pull. We will run a part through repeated load cycles for as long as your specification asks for, and count them.
A static proof test answers one question: did this assembly hold the load once, without deforming. That is what the regulations above require, and for most rigging it is enough.
Cycle testing answers a different question: what happens to this part after the hundredth pull, or the ten thousandth. It is what you want when a component is going into repeated service and somebody needs evidence of how it behaves over a life rather than at a moment. We run the cycle count and the load profile you specify, for as long as it takes, and document it.
A significant share of our testing is done for government and military contracts, where the specification is written down, the tolerances are not negotiable, and the paperwork has to be traceable years later. That work has shaped how we document everything else.
A test is worth what you can prove about it afterwards. Every certificate we issue ties to a serial number, so the document and the piece of steel can always be matched back to each other.
For cycle testing the certificate also records the cycle count and the load profile that was run.
Four separate OSHA paragraphs require proof testing by "the manufacturer or equivalent entity." We have fabricated wire rope and chain slings in Hatfield since 1979, and the test bed is in the same building. When a sling we built needs proof testing, there is no question about who is entitled to do it.
Nelson Wire Rope holds AWRF Accreditation, awarded after an independent third-party audit conducted by the Lifting Equipment Engineers Association (LEEA). The audit examines fabrication processes, inspection practices, technical training and documented quality management, which is the same documentation discipline a test certificate depends on.
Something that fails a proof test has to go somewhere. Because we fabricate and repair in the same building, a failed assembly can be rebuilt, re-tested, re-tagged and returned without a second vendor, a second lead time or a second purchase order.
The mobile unit and our inspectors bill at the same rate, so a site visit can cover proof testing and periodic inspection together. For a facility that has let both lapse, that is usually the cheapest way to catch up.
Tell us what it is, what it is rated at, and whether it can travel.
Proof testing requirements cited on this page are OSHA 29 CFR 1910.184(e)(4) (alloy steel chain slings), 1910.184(f)(4)(ii) (welded end attachments on wire rope slings), 1910.184(g)(5) (metal mesh slings) and 1910.184(i)(8)(ii) (repaired synthetic web slings). Cycle testing is run to customer specification. Capacity, rate and coverage current as of 2026.