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11.3 Bushings
11.3.1 A bushing or the equivalent shall be provided at a point where a flexible cord passes through an
opening in a wall, barrier, or enclosing case. The bushing shall be substantial, reliably secured in place,
and shall have a smooth, rounded surface against which the cord may bear. If Type SP-3 or SPT-3 cord
is employed, the wall or barrier is of metal, and the construction is such that the cord may be subjected
to stress or motion, the bushing shall be an insulating bushing.
Exception: For a cord hole in wood, porcelain, phenolic composition, or other acceptable nonconductive
material, a smooth, rounded surface is considered to be the equivalent of an insulating bushing.
11.3.2 Ceramic materials and some molded compositions are acceptable for insulating bushings.
11.3.3 Vulcanized fiber may be employed if the bushing is not less than 3/64 inch (1.2 mm) thick, and if
so formed and secured in place that it will not be affected adversely by conditions of ordinary moisture.
11.3.4 An insulating bushing molded integrally with the supply cord is acceptable on a Type SP-3 or
heavier cord provided the built-up section is not less than 1/16 inch (1.6 mm) thick where the cord passes
through the enclosure.
11.3.5 An insulated metal grommet is acceptable as an insulating bushing if the insulating material is not
less than 1/32 inch (0.8 mm) thick and completely fills the space between the grommet and the metal in
which it is mounted.
OCTOBER 15, 2004UL 45824B
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