The Different Elements of Machine Guarding

The hazards posed by an unguarded machine are obvious: in the worst of all cases the machine can do to your body parts what it’s doing to the materials it’s designed to cut, shape, or form. One of the major goals of OSHA is to guard all machinery and equipment to eliminate hazards created by points of operation, in-going nip points, rotating points, and flying chips and sparks.

The words “shall be guarded” apply to most machines and equipment the University uses. Some machines require specific guarding methods and all machines are regulated by the general requirements.

There shall be one or more methods of machine guarding provided to protect the operator and other employees in the machine area from hazards. Examples of guarding methods are: barrier guards, two-hand tripping devices, and electronic safety devices.

Types of Guards

Fixed guard – provides a barrier between a person and the point of opera, power train or other moving parts. These include fences, gates, and protective covers for blades, presses and all moving parts.

Interlocked guard – when opened or removed disengage the machine’s power source. It cannot be restarted until the guard is replaced.

Adjustable guard – provide a barrier that can be adjusted to many different operations, such as varying sizes of stock.

Self-adjusting guard – barriers that move or self-adjust, according to the size or position of the workplace. The guard returns to its resting position when no material is passing through.

Affix guards to the machine where possible or secure it elsewhere if for any reason attachment to the machine is not possible. The guard shall be such that it does not offer an accident hazard in itself. Point of operation is the area on a machine where work is actually performed upon the material being processed. The point of operation of machines whose operation exposes an employee to injury shall be guarded. Machine guarding device shall conform with any appropriate standards. If no specific standard exists then the design and construction of the guard will prevent the operator from having any part of his body in the danger zone during the operating cycle.

Revolving drums, barrels, and containers shall be guarded by an enclosure that is interlocked with the drive mechanism so the barrel, drum or container cannot revolve unless the guard enclosure is in place. When the periphery of the blades of a fan Is less than seven feet above the floor or working level, the blades shall be guarded. The guard shall have openings not larger than one-half inch.

Machine guarding designed for a fixed location shall be securely anchored to prevent walking or moving. This guard is good for stationary equipment and materials.