Risk assessment and machinery safety

The rapid development in the field of machine design coupled with the increasing use of fluid power and programmable electronic systems in operating modern machinery has led to an increasing concern for the safety of all personnel involved in machine operation and maintenance.

In many respects, modern machinery tends to pose unique problems and hazards which might differ in nature from those presented by conventional machinery. The introduction of the British Standard Code of practice BS 5304:1988 for Safety of Machinery will benefit manufacturers from a more uniform application of safeguarding principles. Until the European Community legislation and supporting Standards are available, the Code will be the major document detailing how British machinery safety legislation can be complied with. Although the application of risk assessment to machinery safety was explored briefly in the new British Standard, it has very limited application and rigid requirements for safeguarding are still imposed, mainly as a result of ‘experience’ or past accident statistics. Designers feel ‘justifiably’ severely restricted in their innovation by a set of rigid rules presented by the new Standard as well as the EC Directive on Product Liability. This paper considers the role of probabilistic risk assessment as a modern approach to machinery safety through a case history and proposes a guide for the acceptability of risk.