Introduction

The most important step that must be taken with any lifting operation is first to establish the weight of the load. If this essential information cannot be obtained, the person must be able to calculate the weight using their own judgment, and use of the tables or data contained in this manual.

They are:

• Marked on the lift by data plates or marked by other workers, if the weight is marked on the load ensure it is the weight of all parts of the load (a machine tool for example may not include the drive motor).
• Manifest information available from materials department
• Seeking guidance from your supervisor who can obtain the information from manufacturers
• Consult a drawing of the load (if available)
• Input from engineers offshore/onshore
• Calculation by reference to material weight/densities tables

Never underestimate the weight of the load. Always use a sling of the correct Safe Working Load. Personal injury/lost time accidents are more expensive than any sling on the market.

To the estimated weight add 25%. This will account for any error of judgment.

Now select the lifting equipment for the overall estimated weight, that is your estimate plus 25% and sling the load correctly.

The time taken to calculate the approximate weight of any object is time well spent, and may avoid a serious accident through failure of the lifting equipment.