• Introduction
• Preparing
  for Use
• Install/
  Disassembly
• Use of
  Staging
• Key Components
• Topic Glossary

Key Components: Considerations

Component 4. Planking

Specifications for Planking or "Bedsprings"

The standing surfaces typically used in marine hanging staging are of a specialized design and are constructed for hard use. Referred to in the industry as "bedsprings" by virtue of their appearance and material make-up, they vary in length between 2 and 10 feet, depending on desired platform length.

Bedsprings consist of two rails constructed of 1-inch solid steel stock (ASTM 105), 2-inch (OD) 40-gauge steel tubing (ASTM 105) or equivalent, joined by cross members of equivalent strength, spaced between 12 and 27 inches apart, depending on length.

Expanded metal mesh, the standing surface of the bedspring, is welded to the rails and cross members at intervals that prevent no more than 1 inch of downward deflection. The ends of the bedspring rails are equipped with hangers that secure the rails to the staging struts. Bedsprings are wire-tied to the struts at both ends to prevent displacement.

Planking.

Tie wire.

Photo courtesy of VSRA.

Through design criteria established by engineering analyses and failure mode analysis of marine hanging staging components, a duty rating of 500 pounds has been assigned to this type of planking. Thus, no more than two persons and their tools can occupy a single platform at any given time [29 CFR Part 1915.71(b)(1)]. (Note: Relevant engineering analyses were performed or commissioned by the Virginia Ship Repair Association, Inc., or VSRA, and provided to OSHA in association with the preparation of this section of the Ship Repair module of the Shipyard Employment eTool.)