Machine Guarding

Machine Guarding:

(This the first in a series of safety and health bulletins on specific issues developed/adapted for the GCC by Dan Huziak of Toronto 100M.)

Ram Kanojia first started in the printing industry in India on a letterpress when he was thirteen years old. Eventually he migrated to Canada with a three year stopover as a press operator in Germany. Upon his arrival in Canada, he continued to work in the trade and became an offset press operator and a member of GCIU Local 10C. Ram worked approximately 20 years on the presses. One midnight shift while filling the ink fountain, his hand and lower arm were crushed between two unguarded rollers.

After having his cast removed, the Workers Compensation Board put him first in rehabilitation and eventually into a retraining program. Ram is now trying to live on a small disability pension and support from his two daughters. The extent of the injury that Ram received has necessitated continuing physiotherapy for his deteriorating condition. An investigation by the joint health and safety committee (JHSC) found the primary cause of the accident to be the lack of a guard. At the insistence of the JHSC the employer retrofitted the press with proper guarding. Unfortunately, this protective action came too late for Ram.

Machine hazards

Machines used in GCIU workplaces range from guillotines to elevating devices to presses. All of these machines, under some circumstances, can be hazardous to the health and safety of GCIU members. Contact with moving parts can result in lost fingers, hands and arms. Poor design or poor maintenance of machinery, inadequate or inappropriate work processes and lack of training are just a few causes of these accidents.

Machines are potentially hazardous for a number of reasons. They almost always include moving parts that may accidentally come into contact with a worker’s body. Many incorporate other hazards, such as hydraulic and pneumatic systems, electrical circuits, hot exhausts or surfaces and toxic chemicals. When workers come into contact with moving, or otherwise hazardous machine parts, the results can be tragic. It takes only a second for a worker to be killed or maimed. Losing a digit while removing a hickey is no longer an accepted badge of the trade.

Machinery may present hazards from moving, hot, or electrically active parts. The hazards posed by most types of moving machinery are located at two key hazard points: the point of operation, which is where work is being performed by the machine, and points where power transmission components come into contact with one another. Whether they occur at the point of operation or during power transmission, machine hazards involve three kinds of motion: rotating, reciprocating and transverse motion.

Assessing machine hazards

The techniques used to assess machine hazards are similar to those used for other workplace hazards. The first line of defense is the visual inspection of the machine before it is started and every time it is operated. The workplace inspection, conducted regularly by stewards or health and safety committee representatives, is another important assessment tool. Every machine in the workplace must be inspected periodically so that its hazards can be evaluated and controlled.

Workplace inspections must be performed regularly and must not be rushed. An inspection plan ensures that every part of the workplace is inspected periodically. Machine guarding should be treated as a separate inspection item. Referring to a list of machines and their controls, each machine should be observed and its hazards analyzed. The focus should be on identifying unguarded areas as well as assessing the effectiveness of existing guards and safety devices.

Discussions with operators are an important and effective way of assessing machine hazards. Their experience reflects safety factors, as well as flexibility and convenience of operation. Hazard controls work best when everyone affected has a voice in making improvements and believes that the systems used are the most appropriate and effective possible.

A checklist of questions can be a useful tool to ensure that every aspect of each machine is considered. Checklists are only effective, though, when they are customized to account for the unique conditions of each workplace. Each component of an operation can be separately evaluated, as well as the entire work cycle.

Controlling machine hazards

Many standard devices for controlling machine hazards as well as a variety of improvised barriers, enclosures and tools have been developed. All are intended to control worker exposure to machine hazards. Machine guards and other safety devices prevent human contact with hazard points during the normal operation of the machine. Control devices may be used to prevent the operation of the machine while a worker is exposed. In general, these devices are forms of control along the path from the hazard to the worker.

Specific control devices are intended to prevent access to moving parts while they are in motion, prevent parts from moving while the worker is in a danger zone, or contain fragments of particles thrown off by the process or pieces of broken machinery should the machine itself break.

Controls, whether factory-installed or custom, must meet the following criteria:

What can be done?

Health and safety legislation gives workers the right to know about the hazards they are exposed to in the workplace. It is important, and in some cases mandatory, that employers provide training to workers. As well, the local should raise the general awareness of its members about machine and other workplace hazards. Some legislation and contracts also provide for joint health and safety committees (the “Negotiating Effective Joint Health & Safety Committees” bulletin is currently in development).

These committees can then implement controls of machine hazards by: