the workbench. The inside of drawers and cabinets need
the construction features of a safe electric or electronic
not be insulated as they should be left closed while
workbench. The work surface, or top, is usually 30
working on energized circuits or equipment. Don't
inches wide and 4 feet long. The bench must be secured
defeat the purpose of the insulation by attaching vises,
to the deck.
locks, hasps, hinges, or other hardware with metal
Where electrical vinyl sheet deck covering is not
through bolts to the metal parts of the workbench. When
used, matting is installed over the minimum area (not
mounting hardware items, insulate them from the
less than 3 feet wide) to prevent electric shock.
workbench.
Additionally, a rubber matting 3 feet wide is installed to
The workbench must have type D, size 10
insulate the walkway in front of insulated workbenches
grounding leads that are at least 54 inches in length
where electrical grade vinyl sheet is not specified.
according to MIL-W-16878 (fig. 1-5). The ground leads
The top of the working surface of an electric or
must be secured to the ship's structure or at the back of
electronic workbench must be insulated with 3/8-inch
the workbench and must be equipped at the free end with
Benelex 401. All other surfaces should be covered with
a So-ampere power clip (type PC) and insulated sleeving
1/8-inch laminate, including kneeholes under auxiliary
(both conforming to Federal Specification W-C-440).
worktables and bulkheads or other hull structures or
One grounding lead should be installed for every 4 feet
of workbench length to ensure positive grounding of the
equipment attached to the hull that are within 3 feet of
Figure 1-5.--Installation of grounding cable for electric workbench.
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