Roundslings are identified by the vertical rated load shown on the sling identification. The sizes in the first column have been adopted by the Web Sling & Tie Down Association to describe certain polyester roundslings. Source: www.osha.gov.
Ensure that mechanical fittings used with a synthetic round sling are compatible with the mechanical and environmental requirements of the sling. These fittings should have a rated load at least the same as the round sling and be able to sustain twice the rated load of the sling without visible permanent deformation. Their surfaces should be clean, and sharp edges removed.
OSHAs sling standard has always required that slings, fastenings and attachments be inspected for damage or defects each day before use. In addition, the new guidance recommends periodic inspections of synthetic round slings at yearly intervals for normal use, or monthly to quarterly for severe service. In no case should the periodic inspection interval be greater than 12 months.
Missing or illegible sling identification
Acid or caustic burns
Evidence of heat damage
Holes, tears, cuts, abrasive wear or snags that expose the core yarn
Broken or damaged core yarns
Welding splatter that exposes core yarns
Knots in the round sling body, except for core yarn knots inside the cover
Discoloration and brittle or stiff areas on any part of the sling
Pitted, corroded, cracked, bent, twisted, gouged or broken fittings
Other conditions that cause doubt as to the continued use of the sling
Where any such damage or deterioration is present, remove the sling or attachment from service immediately. Repairing synthetic round slings properly is difficult to do and is not recommended.
USE AND STORAGE OF SYNTHETIC ROUND SLINGS
When using synthetic round slings, keep all parts of the human body away from the areas between the sling and the load and between the sling and the crane or hoist hook. Personnel should never stand in line with, or next to, the legs of a sling that is under tension, and must not stand or pass under a suspended load.
Use and store slings in an area where they will not be subjected to mechanical, chemical or ultraviolet damage. They should not be kept in areas with extreme temperatures.
Chemically active environments can affect the strength of synthetic round slings. Consult the manufacturer before using a sling in such environments and be sure that the cover is the same yarn as the load-bearing core.
Long-term exposure to sunlight or ultraviolet radiation can also affect the strength of polyester round slings. Consult the sling manufacturer for proper retirement criteria for polyester round slings subjected to long-term storage or use in sunlight.
Do not allow polyester round slings to be used in contact with hot objects or at temperatures in excess of 194° F, or below -40° F. Some synthetic yarns do not retain their breaking strength during long-term exposure above 140° F.