Guarding machine safety

Regulation 11 (Dangerous Parts of Machinery) of the Provision and Use of Work Equipment Regulations 1998 (PUWER) aims to prevent access into dangerous parts of a machine. However, machine guards are often treated surprisingly casually in the workplace and continue to be the cause of many injuries that could have been prevented had appropriate guards been used. 

The Machinery Directive (2006/42/EC) must now be observed by anyone supplying a machine in the European Union. While standards are guidance documents, they do provide a presumption of compliance. The legal requirement aspect is that guarding must comply with the relevant Essential Health and Safety Requirements (EHSRs) in the Machinery Directive. These cover safety features, including guarding, that manufacturers must build into their machine before it can carry the CE marking to show that it conforms to EU requirements. 

There are a great many EHSRs that apply to guards. Section 1.4.1 of these EHSRs requires that guards must protect against the ejection of falling materials and objects. For example, if a grinding wheel explodes, can the guarding contain that explosion? 

Section 1.4.2.1 requires that all fixed guards must be removable only with the aid of tools, that guards should be incapable of remaining in position when their fixings have been removed and that their fixings need to remain attached to the guard when the guard is removed from the machine. This means that ordinary machine screws and bolts can no longer be used as a means of attaching guards unless provision is made for the screws or bolts to be held captive when the guard is removed.

Also, careful thinking will be required to ensure, for example, that hinged guards open automatically when they are released, and that guards on the top of machines are not retained in position by gravity when their fixings have been removed.

EN Standards

EN standards are the recognised source of guidance across most business sectors and machinery safety is no different. There are in excess of 500 standards relating to all aspects of machinery safety, including guarding. Just a few examples, as mentioned above, are EN 953; EN ISO 13857 and EN 349. These can all be used to ensure that your equipment conforms to the requirements of both the Machinery Directive and PUWER.

Guards and their associated safety devices such as interlocks (covered in EN 1088) can, and often are, defeated. Interlocks, in particular, have been prone in the past to being defeated in order to keep production running. Recent updates of EN 1088 also included suggestions such as gluing and welding in order to prevent defeat by removal.

Review the workplace

Requirements do not just relate to new machinery being brought into the workplace, but also cover existing machines. So, if a maintenance team are not fully aware of the requirements they can fall foul of the law.

Any new guards added to existing machinery must be put through the entire CE marking process, including risk assessment and the compilation of a technical construction file, before a declaration of conformity for CE marking can be made. 

Regulation 10 of PUWER also requires that an employer must ensure that any equipment subject to European Directives complies with all applicable ESHRs of the Directives that apply to it. This includes ensuring that they, or the manufacturers from which they buy machinery, have CE marked their products correctly and followed the right procedures. 

Clearly, achieving full standards compliance for a guard to carry the CE marking is no trivial task. CE marking, along with the design and manufacture of guards, now requires specialist expertise. The plea of ignorance is not acceptable as failing to comply with the Machinery Directive and PUWER – whether knowingly or unknowingly – can have serious and far-reaching consequences for machinery designers, the manufacturers that use them and their operators.