6.3 Ladders, Scaffolds, Roof Brackets & Aerial Lifts (MIOSHA Parts 11, 12 & 32)

MIOSHA Part 11: Portable Ladders

Part 11 (R 408.41101–41140, amended July 25, 2019) adopts the ANSI A14 ladder construction standards and adds Michigan use rules. Part 45 points to Part 11 for fall protection while working on ladders.

Setup (R 408.41124)

• Pitch: the horizontal distance from the top support to the base may be not more than 1/4 of the vertical distance between them. This is the familiar 4-to-1 rule: a ladder reaching a support 20 feet up sits no more than 5 feet out.
• A ladder pitched so the base is less than 1/5 of the height out, meaning too steep, must be secured at the top to prevent tipping backward. A ladder at 80 degrees or more must meet the fixed-ladder rules.
• For roof access, the side rails must extend at least 3 feet above the upper landing. If the ladder is too short for that, it must be secured at the top to a rigid support and a grab rail provided.
• Use safety feet, or tie, block, or otherwise secure the ladder. Slip-resistant feet do not replace care on slippery surfaces.
• Do not splice two ladders together unless they are designed for it. Erect an extension ladder with the fly section resting on the base section, as the rule describes.
• Keep the area around the top and bottom clear. Do not place a ladder in a doorway, passageway, or driveway unless it is barricaded or secured (R 408.41122).

Use (R 408.41122 and R 408.41124)

• Face the ladder, and keep at least one hand grasping it while climbing up or down.
• Do not carry any object or load that could cause you to lose balance. Use a ladder hoist, conveyor, or boom delivery for bundles.
• Do not overreach. MIOSHA defines overreaching as having both shoulders outside a side rail.
• Do not move, shift, or extend a ladder while someone is on it. Single-rail ladders are prohibited.
• On a portable ladder, do not stand on the top 2 rungs or within 3 feet of the top.
• On a stepladder, do not stand on the top step or cap unless it has a handrail. Do not use a stepladder leaned against a wall as a straight ladder. Lock the spreaders (R 408.41126).
• A self-supporting ladder must sustain 4 times the maximum intended load, or 3.3 times for a Type IA extra-heavy-duty metal or plastic ladder. Never load a ladder beyond its rating. Choose a duty rating that covers the worker plus tools and materials. Type I is 250 pounds, Type IA is 300 pounds, and Type IAA is 375 pounds.

Inspection (R 408.41121)

Inspect a ladder before use and after it falls or is in an accident. Immediately tag it "DANGEROUS - DO NOT USE" and withdraw it from service if it has broken, worn, or missing rungs; broken or split side rails; broken or bent guides or spreaders; or broken or bent locks. Repairs must restore the original design. Keep ladders free of slippery substances such as wet asphalt and oil (R 408.41132).

Power Lines

• Do not use a metal ladder for electrical work or where the ladder or worker could contact energized conductors. Use nonconductive side rails where contact with exposed energized equipment is possible.
• A metal ladder may not be used or moved within 20 feet of power transmission or distribution lines (R 408.41124(7)).
• Treat lines as energized unless the utility confirms they are de-energized and visibly grounded. When de-energizing is impractical, keep the ladder, worker, or material at least 10 feet from lines up to 50 kV, plus 0.4 inch per kV above 50 kV.

MIOSHA Part 12: Scaffolds

Part 12 (amended December 2018) contains Michigan rules plus adopted federal scaffold provisions.

Roof brackets and staging planks are a work platform, not a fall arrest system. On steep roofs, the fall protection rules in Section 6.1 still apply. Follow the bracket manufacturer's spacing and fastening instructions.

Aerial Work Platforms and Boom Delivery

MIOSHA Part 32 governs aerial work platforms, and Part 45 refers workers in boom-supported lifts to it. In general, a boom lift occupant wears a harness and lanyard attached to the manufacturer's anchor point. Operators must be trained and must stay within the load chart. Keep all lifts, boom trucks, and conveyors clear of power lines by the required distances. Treat material deliveries by boom truck as crane or hoisting work (Section 6.5).

Worked Example

The eave is 18 feet above level ground. Set the ladder base about 4.5 feet from the wall (18 ÷ 4). Extend the rails 3 feet above the eave, tie off the top, and use a hoist for bundles. Before raising an aluminum ladder near the service drop, confirm it will stay at least 20 feet from power distribution lines. If it cannot, use a fiberglass ladder and keep the required clearance, or have the utility de-energize or cover the line.