Subpart E
The proof load for chains, rings, hooks, shackles, or swivels must be 100 percent in excess of the safe working load (i.e., twice the safe working load). This requirement is set out in 1919.31(a).
A single-sheave block must be tested with a proof load equal to 300 percent in excess of the safe working load (i.e., four times the safe working load). See the proof-load table in 1919.31(a).
The footnote explains that the proof load on a single-sheave block is the same as twice the maximum resultant load on the block eye-pin when lifting the nominal safe working load, which makes the proof load equal to four times the safe working load as defined in (i) or twice the safe working load as defined in (ii). The standard gives two ways to view the block's nominal safe working load: (i) the maximum load safely lifted when the load is attached to a rope passing around the sheave, or (ii) when the load is attached directly to the block it is permissible to use twice the nominal safe working load from (i). See the footnote and definitions in 1919.31(a).
Multiple-sheave blocks have tiered proof-load requirements: - For blocks with safe working load up to and including 20 tons: test at 100 percent in excess of the safe working load (twice the safe working load). - For blocks with safe working load over 20 tons up to and including 40 tons: test at 20 tons in excess of the safe working load. - For blocks with safe working load over 40 tons: test at 50 percent in excess of the safe working load. These requirements are in the proof-load table in 1919.31(a).
Pitched chains used with hand-operated blocks and rings, hooks, shackles, or swivels permanently attached must be tested with a proof load equal to 50 percent in excess of the safe working load (i.e., 1.5 times the safe working load). See the proof-load table in 1919.31(a).
Hand-operated blocks used with pitched chains and permanently attached rings, hooks, shackles, or swivels must be tested at 50 percent in excess of the safe working load (i.e., 1.5 times the safe working load). See the table in 1919.31(a).
If a lead block is positioned so that the two rope parts passing over it never form an acute angle (the angle is always 90° or greater), the block may be rated at no more than one-half the maximum resultant load that can be placed on it. This angle exception is explained in footnote (iii) of 1919.31(a).
Yes — when accredited persons are retained to test special stevedoring loose gear that does not form part of a vessel's equipment, those tests must follow the requirements in 1918.61(b)(1), 1918.61(b)(2), and 1918.61(b)(3). The cross-reference and requirement are stated in 1919.31(b).
After proof testing and before first use, all chains, rings, hooks, shackles, blocks, and other loose gear (except items noted in 1919.32) must be thoroughly examined, with block sheaves and pins removed for inspection to detect injury or permanent deformation; shell bolt nuts must be securely locked when reassembled; and any defective component must be replaced before a certificate is issued. See 1919.31(c).
Any certificate for shackles, swivels, or strength members of single-sheave blocks that have been restored to original dimensions by welding must explicitly state that fact on the certificate. This requirement appears in 1919.31(d).
No. Defective loose gear components must be replaced before a certificate is issued and before the gear is taken into use. This is explicitly required by 1919.31(c).
Loose gear must be proof-tested as required by 1919.31(a) and, after testing, must be thoroughly examined and any defects corrected before being taken into use as required by 1919.31(c). In short: test first, inspect and repair/replace defects, then put into service.
OSHA does not impose a blanket requirement in 1919.31 that every sling hook used with loose gear must have a safety latch; whether a latch is required depends on the specific activity and hazard. OSHA's 2006 letter of interpretation on safety latches explains that latches are required or strongly recommended in many situations and that other OSHA standards and industry consensus standards may call for latch-equipped hooks where necessary to prevent accidental disengagement. See the 2006 interpretation Safety latches on sling hooks for details and examples.