Crane & Hoist – Safe Distance Considerations

The Occupational Health and Safety Act for Industrial Establishments states that a lifting device shall by operated in such a way that no part of the load passes over any worker and that hoisting controls operated from other than a cab or cage shall be located so that they can be operated at a safe distance from the load being lifted.

Pendent controls are used in a large number of factories in North America. Unlike wireless controls, pendent controls are secured to the bridge of the crane and allow the controls to be moved along the bridge but restrict the movement of controls to a few feet in front of or behind the bridge.
If the operator is free to stand a safe distance from the load by placing himself/herself below the bridge the situation should not present a problem. Unfortunately, this is not always the case.

Aisle ways or obstacles often prevent the operator from  walking or standing a safe distance from the load. The operator often walks in front of or behind the load and cannot always maintain a safe distance from the load because the cable length to the controls restricts it.

Keeping loads close to the floor surface reduces the safe distance that an operator must be from the load. Obstacles or stacking requirements often require loads to be elevated which increase the safe distance.
Failures of lifting equipment do occur occasionally and the results can be devastating. Modifications to plant layout or use of wireless controls may allow an operator to stand a greater distance from a load and therefore work in a safer manner.

Suitable Guarding

Countless times I observe guards or guarding devices on machines that are not suitable. The Occupational Health and Safety Act states that a machine shall be shielded or guarded so that product, material being processed or waste stock will not endanger the safety of any worker. A single kind of guard or guarding device does give suitable protection for all different guarding applications.

Please consider the following example of a machine that always runs production parts in automatic or continuous mode. In this example, the operator has to enter the danger zone infrequently to change tooling or for maintenance work. The potential exists whereby parts of the processed material or tooling can break and be ejected out of the front of the machine.

The ejected parts may hit and injure an operator or someone walking by the machine. Are safety light curtains the best way of guarding the machine?

In this case, the safety light curtains would signal a stop of the machine if someone enters the danger zone. If set up properly, dangerous motion of the machine would cease before a person can get trapped or injured. It would not prevent anything from flying out of the machine and hitting someone.

A solid interlocked guard is often the preferred choice in this situation. If designed properly and set up correctly, it stops dangerous motion of the machine when entering the danger zone and may stop objects ejected from the machine.   

It is wise to determine suitable guarding prior to purchase or manufacture of guards and guarding devices.

Emergency Plan for Entrapment Rescue

If someone gets trapped in your punch press, robotic cell or other piece of machinery, can you free the person quickly without causing further injury?

Members of your workforce likely know how to operate your equipment better that anyone else such as firefighters, police or anyone else called to assist in such a rescue.

When someone becomes trapped in machinery, incorrect action or failure to act may cause further injury or death to the victim. An emergency plan is paramount.

A good emergency plan consists of:

• Trained entrapment rescue team members such as millwrights, electricians, first aiders and supervisors.
• Trained non-members of the entrapment rescue team who may be first at the scene of a trapped person.
• A listing of the members of the entrapment rescue team posted in a conspicuous place.
• A means of notifying team members should an entrapment occurs.
• A set of well-developed entrapment rescue procedures for each machine.
• A cart or box containing tools and equipment necessary for rescue purposes.
• Scheduled practice of simulated entrapment situations by the entrapment rescue teams.