Design machinery guards

ISO 14120, Safety of machinery — Guards — General requirements for the design and construction of fixed and movable guards... 

Other standards in the safety area that are most often citied by OSHA and which must be considered in detailed designs are the. National Electric Code and Machinery and Machinery Guarding. A cursory investigation by a designer of these and other OSHA standards quickly points out several problems, particularly in interpretation. The standards frequently do not allow for alternate... 

Every attempt should be made to incorporate facilities for health and safety protection of plant personnel in the original design. This includes, but is not limited to, protected walkways, platforms, stairs, and work areas. Physical hazards, if unavoidable, must be clearly defined. In such areas, means for egress must be unmistakable. All machinery must be guarded with protective devices4 In all cases, medical services and first-aid must be readily available for all workers. 

There is an obligation on employers to provide plant that is safe. Bought out machinery should already be adequately guarded, but for custom designed and built plant, such as process plant, machining stations, robot assemblies, etc., the onus rests firmly with the user to ensure that the plant is safe when put to work. 

This chapter identifies the factors which determine whether a guard or safety device taken together with appropriate systems of work, supervision, instruction, maintenance, and permit-to-work procedures are adequate. In practice the most effective method of preventing machinery accidents, apart from designing out the hazard, is to minimise the need for access, whether operationally-required or unofficially desirable. The effort which has to be devoted to the design of ingenious safety devices, the development of complex systems of work, and the provision of close supervision, is largely a... 

Design faults in machinery are often responsible for operating equipment hazards. If you consider that machinery is composed of power-driven moving parts, to omit guarding from moving parts would place the operator at a great risk if he or she is working in close proximity to the machinery. 

Machine guarding is covered by the various parts of national and international standards. In general, design and construction requirements involved in machinery safety guarding can be summarized to include the following ... 

Safeguarding of machineiy should be planned into the design of machinery. Safety devices, fences, barriers, and guards should not in themselves create a hazard. 

There are several techniques available in guard design using electronic systems however, the vast majority of guarding on machines is still mechanical. Wherever machinery is... 

These are devices which require the operator to have both hands In a safe place (the location of the controis) before the machine can be operated. They are an option on machinery that is otherwise very difficult to guard but they have the drawback that they only protect the operator s hands. It is therefore essential that the design does not allow any other part of the operator s body to enter the danger zone during operation. More significantly, they give no protection to anyone other than the operator. 

British Standards Institution, BS EN 1088 (ISO 14119), Safety of machinery - Interlocking devices associated with guards - Principles for design and selection, BSI, London (1995)... 

The interfacing arrangement between the electrosensitive protective equipment and the machinery control system is a particularly important facet of the safety system s design. It is the overall control system incorporating both the photoelectric guard and the machine s safety-related control system that determines the level of safety that can be achieved. Close attention therefore needs to be paid to the machine s control system and the way in... 

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