Two workers on a construction project were struck and killed when a structural steel beam being hoisted over them slipped out of a lever-action beam clamp.
The investigation revealed that the single clamp being used was too large for the beam and so did not grip the top flange securely. It was also discovered that the clamp used a lever action for gripping. When the tension on the hoist cable was released, the jaws of the clamp could open automatically and release its grip on the flange.
Clamps of this type do not meet the requirements of the Regulations for Construction Projects [O. Reg. 213/91, section 172], which state that "a container, sling or similar device for rigging or hoisting an object, including its fittings and attachments . . . shall be so arranged as to prevent the object or any part of the object from slipping or falling."
Beam clamps that rely on the lever action of the jaws to provide the grip on the beam do not meet the requirements of the Regulations for Construction Projects and therefore should not be used for hoisting structural steel.
For additional information, please call the Ministry of Labour Health & Safety Contact Centre.
This Ministry of Labour Alert has no legal effect and does not constitute and is not a substitute for legal advice. If you require specific assistance with respect to the interpretation of a legislative provision and its potential application to you please contact your legal counsel.
Remember that while complying with occupational health and safety laws, you are also required to comply with applicable environmental laws.
Please photocopy Ministry of Labour Alerts, distribute them widely and post them where people will see them.