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  1. Cranes Module 13

  2. Objectives • After this module you should be able to • identify the most common crane hazards • take the necessary steps to avoid those hazards

  3. Crane Hazards • Improper loading • Not using outriggers or leveling crane • Not calculating load weight correctly • Lifting on unstable support surface • Working around powerlines • Damaged windows and other crane parts • No barrier around swing radius • No or poor regular inspections • No boom angle indicator • Wind and other side forces

  4. Preplanning the Lift • Level the crane to within 1% and ensure support surface is firm, able to support the load • Know the location and voltage of any overhead powerlines; stay 10’ away • Barricade the area within the swing radius • Determine your pickup and drop locations • Calculate the weight of the load and determine how to safely lift that weight • Inspect the crane

  5. Daily Crane Inspection • Some items to inspect include • tires properly inflated • clearance for tail swing • wire rope wear • physical damage to crane • loose or missing hardware • fluid leaks • Inspection must be done by a competent person • If it needs fixed, don’t use it until it is repaired

  6. Load Weight • Refer to the shipping ticket or other documentation • Ensure load is within the load chart rating for the boom length and load radius the operator is using • remember that the crane is rated by the maximum weight it will lift at minimum boom length and minimum radius • the further from the crane’s center point the load is, the less the crane will handle safely

  7. Load Limiting Factors • An operator must also consider the following when calculating for a safe lift • wind • side loads • on wheels or outriggers • lifting over the side • use of extensions, jibs, or other attachments • the limits of rigging • the actual weight of the rigging must be considered

  8. the results of an improperly loaded crane are obvious

  9. the crane operator must have reference to and be familiar with rated load capacities, operating speeds, and special hazard warnings

  10. an illustration of the hand signals used in your company’s crane operations must be posted at the job site

  11. do not stand under a suspended load at any time; use tag lines to guide the load

  12. a warning barrier must be placed so that a worker will not enter the swing radius of the crane

  13. this crane’s window is badly cracked Corrective Action: this crane must be taken out of service and the window replaced

  14. this crane’s outriggers are fully extended and the crane is level; therefore, it is stable

  15. a boom angle indicator must be installed on every crane with variable angle booms

  16. these sheaves are damaged which causes excessive wear on the wire rope Corrective Action: replace the sheaves when they are worn or broken or when their damage will cause damage to the wire rope

  17. a thorough, annual inspection of the hoisting machinery must be made by a competent person the employer shall maintain a record of the dates and results of the inspections

  18. Applicable Standards • 1910.181 Derricks • 1926 Subpart N Cranes, Derricks, Hoists, Elevators, and Conveyors

  19. Your Employer Is Responsible For • Designating competent persons to inspect and operate cranes • Ensuring crane is inspected daily before each use and thoroughly annually • Providing the necessary rigging devices • Responding to and correcting hazards pointed out by you, the worker

  20. You Are Responsible For • Inspecting the crane daily before use • Preplanning the lift • Knowing the load weight and other factors to perform a safe lift • Correcting the hazards you are able to correct • Reporting to your supervisor the hazards you are unable to correct

  21. Case Study • Workers were in the process of disassembling the boom. When the pins were driven out, the boom fell onto the workers.

  22. Always Remember • Level the crane within 1% and ensure a firm support surface • Stay 10’ from overhead powerlines • Consider other factors such as wind and side loads when calculating for a safe lift • Inspect the crane before each use and perform a thorough inspection annually • Never operate a crane that has any component in need of repair

  23. Memory Check • A crane must be level to what percentage before a lift? • 1 • 5 • 10 • 12.5

  24. Memory Check • Which of the following is not a factor that affects the load calculation? • the limits of the rigging • the weight of the rigging • the wind speed • all of the above must be considered