OHS Code Explanation Guide

Published Date: July 01, 2009
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Part 21 Rigging

Section 298 Slings

Synthetic fibre web slings are constructed of flat webbing. This webbing is typically layered into plies with more plies meaning a stronger sling. To ensure that the sling and the way it is used is appropriate for the load, working load limits and the information listed in this section must be permanently and legibly marked on the sling (See Figures 21.8 and 21.9).

Figure 21.8 Example of manufacturer’s load limits for synthetic web slings

Figure 21.9 Example of a tag used to mark a sling

Subsection 298(2)

Typically, sling manufacturers verify sling load ratings by pull-testing in excess of 100 percent of the rated capacity. This is often done in accordance with a technical standard such as ASME Standard B.30.9-2006. Pull-testing for recertification purposes must be done this way as well.

If improperly pull-tested or pulled repeatedly beyond rated capacity, a sling’s safety factor can be reduced to an unsafe level, leading to premature failure due to undetected fatigue damage. The pull testing described in this subsection refers to pull testing conducted at a work site, perhaps as part of an inspection or quality assurance program. This pull testing does not apply to manufacturers. Subsection 297(1) applies to manufacturers.