10.2 Crane-Suspended Personnel Platforms (230 CMR 6.09(6) & OSHA 29 CFR 1926.1431)

When personnel hoisting is allowed

230 CMR 6.09(6) prohibits hoisting, lowering, swinging or traveling while anyone is on the load or hook, except when conventional means of access to an elevated worksite, such as scaffolds or ladders, would be impossible or more hazardous. OSHA 29 CFR 1926.1431 states the same test: the employer must show that conventional means would be more hazardous or not possible because of structural design or worksite conditions. Schedule pressure is never a reason.

The Massachusetts text refers to the older federal rule (29 CFR 1926.550(g)(3)–(8)). Today's federal rule is 29 CFR 1926.1431. Under 230 CMR 6.08(1), where the two differ, the higher standard for safety prevails.

Crane or derrick requirements

Platform design and condition

• Designed with a minimum safety factor of five, by a professional engineer or a qualified person competent in structural design. The suspension system minimizes tipping as occupants move. OSHA adds that the platform must stay within 10 degrees of level.
• Standard guardrail system, enclosed from the toeboard to the mid-rail (OSHA: solid material or expanded metal with openings no larger than ½ inch); an inside grab rail; adequate headroom; a plate or permanent marking showing the platform's weight and rated capacity.
• Overhead protection and hard hats where occupants are exposed to falling objects.
• Access gates must not swing outward during hoisting and must have a restraining device against accidental opening. OSHA allows an outward-swinging gate only where an inward gate is infeasible, such as on a one-person platform.
• Rough edges ground smooth. Welding done by a qualified (certified) welder familiar with the weld grades and materials in the design.

Loading and rigging

• Never load beyond the platform's rated capacity. Carry only instructed personnel with the tools, equipment and materials for the task, secured and evenly distributed.
• A wire rope bridle connects to a master link or shackle so the load divides evenly among the legs. Bridles and rigging for the platform are used for no other purpose.
• Hooks must be closed and locked to eliminate the throat opening, or use an alloy anchor-type shackle with a bolt, nut and retaining pin. "Mousing" (wrapping wire across the hook opening) is not permitted.

Trial lift, inspection and proof test

1. Trial lift: the unoccupied platform, loaded at least to the anticipated lift weight, is lifted from ground level (or the entry point) to each location where it will be positioned, immediately before placing personnel on it. OSHA requires the trial lift immediately prior to each shift in which personnel will be hoisted, and again whenever the crane is moved to a new location, returned to a previous one, or the lift route changes (unless a competent person finds no new hazard).
2. During the trial lift the operator checks that systems, controls and safety devices work, that there are no interferences, and that every configuration needed stays within the 50% limit.
3. After the trial lift, the platform is hoisted a few inches and inspected to confirm it is secure and balanced.
4. Before employees are hoisted, check that hoist ropes are free of kinks, multiple-part lines are not twisted around each other, the primary attachment is centered over the platform, there is no slack in the wire rope, and all ropes are properly seated on drums and sheaves.
5. A competent person visually inspects the crane or derrick, the platform and the base support or ground for defects or adverse effects. Defects are corrected before hoisting personnel.
6. Proof test: when the platform is first brought to the jobsite and after any repair or modification, before personnel are hoisted, the platform and rigging are loaded to 125% of the platform's rated capacity, with the load evenly distributed, and held suspended for five minutes. A competent person inspects. Any problem is fixed and the test repeated. OSHA allows the proof test to run concurrently with the trial lift.

Pre-lift meeting

Held before the trial lift at each new work site, and repeated for any newly assigned employee. Attendees: the crane or derrick operator, signal person(s), the employees to be lifted, and the person responsible for the hoisting operation. The meeting reviews the requirements and the procedures to be followed.

Safe work practices

Occupants:

• Use tag lines unless doing so creates an unsafe condition.
• Keep all body parts inside the platform while it is raised, lowered or positioned.
• Secure the platform to the structure before entering or exiting, unless that creates an unsafe condition.
• Wear a body harness with a lanyard. 230 CMR 6.09(6)(h)4 allows the lanyard to attach to the lower load block or overhaul ball, or to a structural member within the platform. OSHA 1926.1431(k)(10) requires attachment to a structural member within the personnel platform. Because the higher standard prevails, tie off to the platform's structural member. Over water, the over-water rules apply instead (OSHA 1926.106).
• Stay in view of, or in direct communication with, the operator or signal person.

Operators:

• Never leave the controls while the engine is running or the platform is occupied.
• Stop all hoisting when there are signs of dangerous weather or other impending danger. Under OSHA, if wind (sustained or gusts) exceeds 20 mph at the platform, a qualified person must decide whether lifting is safe, and it must not begin or continue if not.
• No lifts on any other load line while personnel are hoisted.
• OSHA 1926.1431(n): no personnel hoisting within 20 feet of a power line up to 350 kV, or within 50 feet of one over 350 kV (except work under OSHA Subpart V).

Moving the crane with personnel aboard (230 CMR 6.09(6)(i))

Travel is prohibited unless the employer shows it is the least hazardous way, or portal, tower or locomotive cranes are used. When traveling: travel is restricted to a fixed track or runway, limited to the boom's radius during the lift, with the boom parallel to the direction of travel, after a complete trial run. For rubber-tired cranes, check tire condition and pressure and apply chart capacities that keep the lift under the 50% limit.

Worked capacity check

A crane's chart rates 9,600 lb at the planned radius and configuration. The platform weighs 950 lb and is rated 1,000 lb. The bridle and shackles weigh 120 lb, and the hook block 380 lb.

• 50% limit: $9{,}600 \times 0.50 = 4{,}800$ lb total.
• Fixed weight counted against it (OSHA counts hook, load line and rigging): $950 + 120 + 380 = 1{,}450$ lb.
• Available for people, tools and materials under the crane limit: $4{,}800 - 1{,}450 = 3{,}350$ lb. But the platform's own rating of 1,000 lb governs, because the platform may never be loaded beyond its rated capacity.
• Proof test load: $1{,}000 \times 1.25 = 1{,}250$ lb, evenly distributed, held for 5 minutes.