Subpart E
Scaffolds and their supports must be able to carry their intended loads with a safety factor of at least four. See the requirement in 1915.71(b)(1).
You must use spruce, fir, long-leaf yellow pine, Oregon pine, or wood of equal strength for scaffold lumber; hemlock, short-leaf yellow pine, and short-fiber lumber are prohibited. See 1915.71(b)(2).
Lumber used in scaffolds must be sound, straight-grained, and free of defects that impair strength (for example: cross grain, large or loose knots, dry rot, large checks, or worm holes). See 1915.71(b)(4).
No — unstable items like barrels, boxes, cans, loose bricks, or similar objects must not be used as working platforms or supports for scaffold planking. See 1915.71(b)(6).
A competent person must supervise any erection, move, dismantling, or alteration of a scaffold. See 1915.71(b)(7).
No — welding, burning, riveting, or other open flame work must not be performed on staging that is suspended by fiber rope. See 1915.71(b)(8).
Lifting bridles on crane‑suspended working platforms must have four legs attached to assure platform stability, and if the crane hook lacks a safety latch or is not moused the bridles must be attached by shackles to the lower block or otherwise positively secured to prevent accidental disengagement. See 1915.71(b)(9) and 1915.71(b)(10).
Pole uprights must be set plumb on a foundation that distributes load and prevents displacement; light‑duty poles (≤24 ft) may be spliced by overlapping at least 4 ft with secure nailing and a cleat support, while taller poles require squared ends fastened with at least two cleats overlapping 24 inches and with combined cleat area at least equal to the pole cross‑section. See 1915.71(c)(1), 1915.71(c)(2) and 1915.71(c)(3).
Independent pole scaffolds must have diagonal bracing between parallel poles and cross bracing between inner and outer poles (or from outer poles to ground), and member dimensions/spacing must follow Table E‑1 in [1915.118]. See 1915.71(c)(6) and 1915.71(c)(7).
Platform planking must generally be at least 2 × 10 inch straight‑grained lumber free from large or loose knots, platforms should be at least two 10‑inch planks wide unless impossible, and planks must project 6–12 inches beyond supports (or be fastened). Table E‑4 in [1915.118] is used as a guide for safe loads. See 1915.71(i)(1), 1915.71(i)(2), 1915.71(i)(3), and 1915.71(i)(4).
Rails are required on scaffolds, staging, runways, or platforms supported or suspended more than 5 feet above a solid surface (or any height above water); the top rail must be 42–45 inches above the work surface with a midrail halfway between the top rail and platform. If rails cannot be installed because the vessel structure prevents their use, employees working more than 5 feet above solid surfaces must be protected by safety belts and lifelines meeting [1915.159] and [1915.160], and employees over water must wear buoyant work vests meeting [1915.158(a)]. See 1915.71(j)(1) and 1915.71(j)(3).
Rails must be of 2 × 4 inch lumber, flat bar, or pipe; taut wire or fiber rope of adequate strength may be used with rigid supports, but when the distance between supports exceeds 8 feet the rails must be equivalent in strength to 2 × 4 lumber; rails must be firmly secured and fiber rope must not be used where exposed to hot work or chemicals. See 1915.71(j)(2).
Access to staging over 5 feet above a floor, deck or ground must be provided by well‑secured stairways, cleated ramps, fixed or portable ladders meeting [1915.72], or rigid non‑collapsible trestles with parallel and level rungs; ramps and stairways must have 36‑inch handrails with midrails, and ladders must be located so employees do not have to step more than one foot from the ladder to an intermediate landing or platform. See 1915.71(k)(1), 1915.71(k)(2), and 1915.71(k)(3).
Supporting hooks must be forged, equivalent in strength to mild steel or wrought iron, at least 7/8 inch in diameter, and secured to a safe anchorage; ropes must be equivalent to first‑grade 3/4 inch manila properly rigged into standard 6 inch blocks (with at least one double and one single block); both manila and wire ropes must be examined before each operation and as frequently as needed. See 1915.71(f)(1), 1915.71(f)(2), and 1915.71(f)(3).
No more than two people may work at one time on a swinging scaffold built to the minimum specifications; if the scaffold is constructed heavier than the minimum, the allowable number of persons is determined by the scaffold's size and safe working load. See 1915.71(f)(8).
Plank‑type platforms must use planks of at least 2 × 10 inch lumber, be no more than 24 inches wide, have planks tied together by 1 × 6 inch cleats nailed on the underside at intervals ≤4 feet, extend 6–18 inches beyond supporting stirrups, and have a cleat nailed across the underside at each end outside the stirrup to prevent slipping. See 1915.71(f)(12)(i), 1915.71(f)(12)(iii), 1915.71(f)(12)(iv), and 1915.71(f)(12)(v).
Ladder‑type platforms must have side rails no more than 20 inches apart, side rails equivalent in strength to specified spruce beams (see Table E‑2 in [1915.118]), and be tied together with tie rods of at least 5/16 inch diameter located no more than 5 feet apart, passing through the rails and riveted tight with washers; rungs must be of straight‑grained oak, ash, or hickory at least 1⅛ inches diameter with specified tenons and spacing. See 1915.71(f)(11) and the tie‑rod requirement in the same section.
Side rails for trestle ladders up to 16 ft tall must be at least 15/16 × 2 3/4 inch lumber, and for 16–20 ft must be at least 15/16 × 3 inch; extension section rails have specific minimum widths by length as listed in [1915.71(e)(2)–(3)]; trestles must be spread so the bottom inside‑to‑inside spread is at least 5½ inches per foot of ladder length, and the bottom width must be at least 21 inches for ladders ≤6 ft (wider for longer ladders). See 1915.71(e)(2), 1915.71(e)(3), and 1915.71(e)(4).
Horses (sawhorse‑type supports) must have lateral leg spread equal to at least one‑third of the horse's height, be kept in good repair, and be properly secured when used in staging or where they may be insecure. See 1915.71(g)(3) and 1915.71(g)(4).
If a scaffold type is not specified in 1915.71, it must still meet the general requirements of paragraphs (b), (i), and (j), follow recognized design principles, and be constructed in accordance with accepted standards for that equipment. See 1915.71(h)(1).
Beam‑type platforms must use side stringers of sound straight‑grained lumber not less than 2 × 6 set on edge, have stringer spans between stirrups not more than 16 feet, be bolted to stirrups with U‑bolts and nuts tightened on the inside face, have ends extending 6–12 inches beyond stirrups, supported cross beams of 2 × 6 spaced ≤4 feet on centers, and be no more than 24 inches wide. See 1915.71(f)(13)(i)–(vii).
Employees on swinging scaffolds that are triced out of vertical line under their supports or on paint floats subject to surging must be protected against falling toward the vessel by either a railing or by a safety belt and line attached to the backrail; to prevent tools and materials from falling on workers below, toeboards of at least 1 × 4 inch lumber must be provided where necessary. See 1915.71(j)(4) and 1915.71(j)(5).