By law, almost all commercial and industrial lifting equipment must be inspected every six or twelve months (depending on what it is used for) for defects, damage, and signs of wear or corrosion. These regular examinations have been found to be effective in preventing accidents as any problem with the equipment will usually be spotted before it becomes critical and can be repaired. Thorough examination of industrial equipment saves lives, and ensuring all the machinery is in safe working order is the responsibility of equipment owners, equipment operators and the administrators of the site where the equipment is active.
Exactly what a lifting equipment inspection should entail should be decided by someone who qualifies as a Competent Person under LOLER (Lifting Operations and Lifting Equipment Regulations 1998). Most inspections consist of little more than a visual examination of all the moving parts of the equipment and checking that each part functions properly through its full range of motion, but under some circumstances, it is desirable to perform more extensive testing. One test which can be required is a Proof Load Test.
Proof Load Testing
‘Proof testing’ involves testing the strength or resilience of a product beyond its normal limits to prove that it is able to safely operate within those limits. One of the earliest occasions on which a proof test was applied to mass-produced items was in response to the concerns surrounding the swords issued to British servicemen during the Crimean war. The quality of the swords was found to be highly inconsistent, leading to the British government introducing a requirement that all new swords to be sent to the front should be checked for strength and elasticity in a series of tightly controlled tests, including being bent out of shape and having weights dropped on them. Only swords which passed all the tests were sent to the army.
Proof Load Test for Lifting Equipment
In the context of lifting equipment, Proof Load Testing is carried out by using the equipment to lift a load which is heavier than it was intended to lift during normal operation. The load will usually be 1.1 to 1.5 times the design load or MAWL (Working Load Limit). If the load is successfully lifted for a set period of time without any adverse effects to the gear, it is held that the equipment is safe to be used to lift loads up to its WLL. Each Proof Load Test should ideally be carried out jointly by the equipment operator and someone recognised by LOLER as a Competent Person.
Proof Load Testing is required under the following circumstances:
- Before an item of lifting equipment is put into service
- Following structural repairs, such as component replacement or welding
- After an overhaul or exceptional maintenance
- Following an incident, such as a breakdown
Sometimes a customised test rig must be built to effectively perform a Proof Load Test on particular equipment. You can find out about our bespoke fabrication service here.