Background

On May 21, 2013, a new worker was fatally injured when the steel plate that he was moving horizontally with an overhead crane and plate hooks suddenly slipped off the hooks and fell onto the worker. It was the worker's third week on the job and first day doing this specific task.

The inch-thick hardened steel plate being moved was eight feet wide, 24 feet long, and weighed 3,556 kg. The plate was being removed from a stack of plates to an adjacent cutting table.

The illustration shows an unsafe lifting arrangement for a 1 inch steel plate. It shows a pair of pup hooks, each attached with two hooks and two chains secured to a spreader beam, which is hooked to a crane.

Figure 1: Lifting arrangement for 1" steel plate

The plate was being lifted and moved with a pair of pup hooks (also known as plate hooks), each attached with two hooks and two chains secured to a spreader beam hooked to the crane (see photo above).

As the plate was being manoeuvred, the plate hooks slipped off the plate. The plate then fell onto the worker, injuring the worker fatally.

Steel plates must never be hoisted in this manner because the material may fall as a result of the hooks being dislodged if the plate unexpectedly shifts because of an unbalanced load or an accidental slackening of the hoisting chains.

Hazard summary

Improper design, use and maintenance of hoisting and rigging equipment can cause the equipment to fail or the material to fall, potentially injuring or killing a worker.

Locations and sectors

This Alert applies to any sectors that lift and/or handle materials using lifting devices, including but not limited to fabrication, automotive, construction, industrial services, live entertainment, and the steel industry.

Precautions

Employers must develop proper procedures for handling different materials in their workplace, including proper hoisting and rigging procedures.

Employers must ensure that appropriate equipment is provided and maintained for the specific material being handled.

Employers must ensure that workers are adequately instructed, trained and supervised in the operation of lifting devices and proper hoisting and rigging procedures specific to the material being handled.

Employers must ensure that all hooks, clamps, fittings or attachments used in conjunction with chains, cables or wire ropes attached to the crane or spreader bar are properly and positively secured to the material being moved. The hooks, clamps, fittings or attachments must not be able to be dislodged:

  • if the plate inadvertently makes contact with the floor, other object or any other surface
  • if any object strikes the chains
  • by any sudden movement of the hook or attachment or
  • by the accidental slackening of the hoisting chains, cables or ropes

The use of "positive engagement clamps" (i.e. secured in place so they cannot be dislodged due to accidental contact or slackening of the chain) is one way to ensure that clamps are properly secured to the material at all times.

The material must not be able to slide out of the hooks or clamps if the material shifts for any reason.

The employer should ensure that the manufacturer's specifications are followed including use, maintenance and limitations. The clamps used should be appropriate for the lifting tasks to ensure the lift can be done safely.

Applicable legislation and pertinent standards

This resource does not replace the Occupational Health and Safety Act (OHSA) and its regulations, and should not be used as or considered legal advice. Health and safety inspectors apply the law based on the facts in the workplace.

Sections 25 to 28 of the Occupational Health and Safety Act set out the roles and responsibilities of employers, supervisors and workers to protect the health and safety of workers. These requirements apply to all activities in the workplace, including when material is being hoisted and/or moved by a lifting or rigging device.

The following sector-specific regulations under the OHSA prescribe requirements for lifting devices and hoisting and rigging equipment.

Industrial Establishments Regulation (Reg. 851/90)

  • Section 45: Material, articles, or things shall be lifted, carried, moved, transported, placed, stored or removed in a manner that will not endanger the safety of any worker.
  • Section 51 (1)(a): Lifting devices shall be constructed of such strength and equipped with suitable ropes, chains, slings, and other fittings to adequately ensure the safety of workers.
  • Section 51 (2)(a): Lifting devices must be operated by a competent person or a worker being instructed who is accompanied by a competent person.
  • Section 51 (2)(b): No load to pass over any workers, and one or more guide ropes to be used to prevent rotation or other uncontrolled motion of the load.

Construction Projects Regulation (O. Reg. 231/91)

  • Section 37: Materials or equipment at a project shall be stored and moved in a manner that does not endanger a worker.
  • Section 38: Blocking, support chains, metal bands, wire rope and rigging components shall be removed from material or equipment in a manner that does not endanger a worker.
  • Section 113: No object or material shall be placed, left or stored in a location or manner that may endanger a worker.
  • Section 150: No worker shall operate a crane or similar hoisting device unless the worker holds a certificate of qualification issued under the Ontario College of Trades and Apprenticeship Act, 2009, that is not suspended, or the worker is an apprentice and is working pursuant to a training agreement registered under that Act, that is not suspended, in the trade of;
    1. hoisting engineer – mobile crane operator 1, if the worker is operating a crane or similar hoisting device capable of raising, lowering or moving any material that weighs more than 30,000 pounds;
    2. hoisting engineer – mobile crane operator 1 or hoisting engineer — mobile crane operator 2, if the worker is operating a crane or similar hoisting device capable of raising, lowering or moving only material that weighs more than 16,000 pounds but no more than 30,000 pounds; or
    3. hoisting engineer – tower crane operator, if the worker is operating a tower crane.
  • Section 172: (1) A container, sling or similar device for rigging or hoisting an object, including its fittings and attachments;
    1. shall be suitable for its intended use;
    2. shall be suitable for and capable of supporting the object being rigged or hoisted;
    3. shall be so arranged as to prevent the object or any part of the object from slipping or falling;
    4. shall be capable of supporting at least five times the maximum load to which it may be subjected; and
    5. shall be capable of supporting at least ten times the load to which it may be subjected if it is to be used to support a person.
  1. A sling or similar device made of web-type fabric or nylon shall be labeled to indicate its load rating capacity.
  2. No sling or similar device for rigging or hoisting made of web-type fabric or nylon shall be used if it may be cut.
  • Section 178: A friction-type clamp used in hoisting materials shall be constructed so that an accidental slackening of the hoisting cable does not release the clamp.
  • Section 179: (1) If a worker may be endangered by the rotation or uncontrolled motion of a load being hoisted by a crane or similar hoisting device, one or more guide ropes or tag lines shall be used to prevent the rotation or uncontrolled motion.
  1. No guide rope or tag line shall be removed from a load referred to in subsection (1) until the load is landed and there is no danger of it tipping, collapsing or rolling.

Resources

IHSA Hoisting and rigging safety manual

ASME B30.20, below-the-hook lifting devices

Workplace safety and prevention services

Ontario.ca e-Laws

Or contact the Ministry of Labour Health & Safety Contact Centre at 1-877-202-0008.