Current through Register Vol. 54, No. 50, December 14, 2024
Section 139a.24 - Mobile platforms(a) A mobile platform and suspension system shall be certified by a licensed professional engineer competent in structural design as being in conformity with this chapter.(b) A mobile platform used for lifting site personnel or jumpers shall be designed to meet the following criteria and specifications:(1) The suspension system shall be designed to minimize tipping of the platform due to movement of the individuals occupying the platform.(2) The mobile platform shall be capable of supporting, without failure, its own weight and at least five times its maximum intended load.(3) The mobile platform shall be equipped with a guardrail system and shall be enclosed from the toe board to mid-rail.(4) A grab rail shall be installed inside the entire perimeter of the mobile platform.(5) The mobile platform shall be designed and maintained with an access gate that opens to the inside of the platform and shall have a safety lock or restraining device to prevent accidental opening.(6) The mobile platform shall have anchor points for safety harnesses or safety belts for all persons carried on the platform. The anchor points shall be designed and placed to best suit the movements of anyone on the platform.(7) The mobile platform shall be free of rough or exposed edges.(8) The mobile platform shall have a slip resistant floor surface.(9) Welding of the mobile platform and its components shall be performed by a qualified welder familiar with the weld grades, types and materials specified in the platform design.(10) The mobile platform shall be conspicuously posted with a plate or other permanent marking which indicates the weight of the platform and its rated load capacity or maximum intended load.(c) When a wire rope bridle is used to connect the mobile platform to the load line, each bridle leg shall be connected to a master link or shackle in such a manner to ensure that the load is evenly divided among the bridle legs.(d) Hooks on overhaul ball assemblies, lower load blocks or other attachment assemblies shall be of a type that can be closed and locked.(e) Wire rope, shackles, rings, master links and other rigging hardware shall be capable of supporting, without failure, at least five times the maximum intended load applied or transmitted to that component.(f) The eyes in wire rope shall be fabricated with thimbles.(g) At each new set-up, and at least annually, prior to hoisting individuals in the mobile platform, the mobile platform, rigging and hook block shall be proof tested to 125% of the mobile platform's rated capacity by holding it in a suspended position for 5 minutes with the test load suitably distributed on the mobile platform. The proof test shall be conducted by site personnel or other persons designated by the site operator. After proof testing, deficiencies revealed by inspection by a qualified inspector shall be corrected and another proof test shall be conducted. A modification to mobile platform or rigging shall require retesting of the mobile platform.(h) A trial lift with the unoccupied mobile platform loaded at least to the anticipated lift weight shall be made from ground level, or another location where individuals will enter the platform, to each location at which the mobile platform is to be hoisted and positioned. This trial lift shall be performed immediately prior to placing individuals on the platform. The operator shall determine that all systems, controls and safety devices are activated and functioning properly; that no interferences exist; and that the configurations necessary to reach the jump locations will allow the operator to remain under the 50% limit of the hoist's rated capacity. After a trial lift, and just prior to hoisting individuals, the mobile platform shall be hoisted a few inches and inspected to ensure that it is secure and properly balanced. An individual may not be hoisted unless the following conditions are determined to exist:(1) Hoist ropes shall be free of kinks.(2) Multiple part lines may not be twisted around each other.(3) The primary attachment shall be centered over the platform.(4) The hoisting system shall be inspected if the load rope is slack to ensure all ropes are properly seated on drums and in sheaves.(i) The rigging system may not be attached directly to the mobile platform. The rigging system shall be attached to the lifting system by at least two rigging system attachment points, and shall pass through or around the mobile platform in such a manner as to avoid damage to the rigging system.(j) The persons on the mobile platform shall wear a safety harness or safety belt.(k) The mobile platform shall be limited to a capacity of four persons.(l) Individuals shall keep all parts of their bodies inside the mobile platform during raising and lowering to avoid pinch points. Individuals may not stand on the top rail, midrail or toe board of the mobile platform.(m) A mobile platform may not be used in winds in excess of 25 miles per hour, electric storms or other adverse weather conditions which could affect the safety of individuals. The jump master shall cease jumping operations in wind speeds of less than 25 miles per hour if the wind speed affects the safe operation of the mobile platform or the recovery area.(n) Nothing shall be added to the mobile platform to affect its stability in the wind.(o) If the mobile platform is accidentally lowered onto the cords, the cords shall be inspected before jumping is continued.(p) The jump direction shall be perpendicular to the boom, as viewed from above.