Product Overview

Summary: This SOP provides a clear, step-by-step method for calculating load weights and confirming crane capacity before any lift takes place. It helps Australian businesses prevent overloading incidents, structural failures, and costly downtime by standardising how lifting calculations are performed and documented on site.

Incorrect or incomplete load weight calculations are one of the leading contributors to crane incidents, near misses, and expensive plant damage across Australian worksites. This Safe Operating Procedure sets out a robust, repeatable process for determining the total load to be lifted, checking it against crane load charts, and verifying that all lifting components are appropriately rated. It guides workers through each stage of the calculation, from gathering load data and assessing centre of gravity, to factoring in lifting gear, dynamic effects, and environmental conditions.

Designed for construction, manufacturing, mining, utilities, and maintenance environments, this SOP helps organisations move beyond “rule of thumb” estimates and undocumented decisions. It provides a documented method that supports due diligence under WHS legislation, reduces the risk of crane overloading, and improves communication between crane operators, doggers/riggers, supervisors, and engineers. By implementing this procedure, businesses can demonstrate that every lift is planned, calculated, and authorised using a consistent, defensible approach aligned with Australian standards and industry best practice.

Key Benefits

• Ensure every lift is backed by documented, repeatable load weight calculations rather than guesswork.
• Reduce the risk of crane overloading, structural failure, and dropped loads through systematic capacity checks.
• Improve compliance with Australian WHS duties by evidencing lift planning and engineering control of lifting operations.
• Standardise communication between crane operators, doggers/riggers, and supervisors using a common calculation and sign-off process.
• Minimise project delays, rework, and equipment damage by identifying unsuitable lifts before mobilisation.

Who is this for?

• Crane Operators
• Doggers and Riggers
• Site Supervisors
• Construction Project Managers
• WHS Managers
• Engineering Managers
• Maintenance Supervisors
• Logistics and Yard Coordinators

Hazards Addressed

• Crane overloading leading to structural failure or overturning
• Dropped loads due to underestimating weight or centre of gravity
• Failure of slings, shackles, and lifting accessories from exceeding Working Load Limits (WLL)
• Crane instability caused by incorrect radius or boom configuration assumptions
• Struck-by incidents to workers from swinging or uncontrolled loads
• Damage to plant, equipment, and structures from miscalculated lifts
• Secondary incidents arising from emergency responses to crane failures

Included Sections

• 1.0 Purpose and Scope
• 2.0 Definitions and Terminology (WLL, SWL, radius, dynamic factors, centre of gravity)
• 3.0 Roles and Responsibilities (Crane Operator, Dogger/Rigger, Supervisor, Engineer)
• 4.0 Applicable Legislation, Standards and Guidance Material
• 5.0 Pre-Lift Planning Requirements
• 6.0 Information Required for Load Weight Calculations
• 7.0 Methods for Determining Load Weight (drawings, manufacturer data, calculations, estimation techniques)
• 8.0 Calculating Total Lifted Weight (load, lifting gear, rigging, attachments)
• 9.0 Assessing Centre of Gravity and Load Stability
• 10.0 Applying Safety Factors and Dynamic Load Considerations
• 11.0 Interpreting Crane Load Charts and Verifying Capacity
• 12.0 Verifying Ratings of Slings, Shackles and Lifting Accessories
• 13.0 Environmental and Site Condition Considerations (wind, ground conditions, obstructions)
• 14.0 Documentation, Calculation Sheets and Record Keeping
• 15.0 Communication and Pre-Lift Briefing Requirements
• 16.0 Change Management for Variations to Load or Configuration
• 17.0 Competency, Training and Authorisation Requirements
• 18.0 Monitoring, Review and Continuous Improvement of Calculation Practices

Legislation & References

• Work Health and Safety Act 2011 (Cth) and equivalent state and territory WHS Acts
• Work Health and Safety Regulation 2011 (Cth) and equivalent state and territory WHS Regulations (plant and high risk work sections)
• Safe Work Australia – Code of Practice: Managing the Risks of Plant in the Workplace
• Safe Work Australia – General Guide for Cranes
• AS 2550 series: Cranes, hoists and winches – Safe use
• AS 1418 series: Cranes, hoists and winches – Design and construction
• AS 4991: Lifting devices
• AS 1353 / AS 4497 / AS 3775: Flat synthetic webbing slings, round slings and chain slings for lifting purposes