This Directive applies to machinery and assemblies of machinery installed on industrial sites, an assembly of machinery being arranged and controlled so that it functions as an integral whole.

Assembly of machinery In the case of machinery or parts of machinery designed to work together, the machinery must be designed and constructed in such a way that the stop controls, including the emergency stop devices, can stop not only the machinery itself but also all related equipment, if its continued operation may be dangerous.

Further guidance on assemblies of machinery comprising new and existing machinery is given at paragraph 39 of the European Commission Guide to the Machinery Directive.

A group of machines that are connected to each other but where each machine functions independently of the others is not considered to be an assembly of machinery in the above sense.

The definition of assemblies of machinery does not cover a complete industrial plant consisting of a considerable number of machines, assemblies of machinery and other equipment originating from different manufacturers.

However, for the application of the Machinery Directive, such large installations can usually be divided into sections which may be considered as assemblies of machinery.

The person constituting an assembly of machinery is considered as the manufacturer of the assembly of machinery and is responsible for ensuring that the assembly as a whole complies with the health and safety requirements of the Machinery Directive.

In some cases, the manufacturer of the assembly of machinery is also the manufacturer of the constituent units.

Assemblies of machinery are subject to the Machinery Directive because their safety depends not just on the safe design and construction of their constituent units but also on the suitability of the units and critically the safety of the interfaces between them.

The risk assessment to be carried out by the manufacturer of an assembly of machinery must therefore cover both the suitability of the constituent units for the safety of the assembly as a whole and the hazards resulting from the interfaces between constituent units (such as the need for extra guarding).

The Declaration of Conformity for complete machines and the Declaration of Incorporation and the assembly instructions for partly completed machinery incorporated into the assembly of machinery must be included in the technical file for the assembly of machinery.

The technical file for the assembly of machinery must also document any modifications that have been made to the constituent units when incorporating them into the assembly.

In some cases, one or more of the constituent units of existing assemblies of machinery may be replaced by new units, or new units may be added to an existing assembly of machinery.

The question arises as to whether an assembly of machinery comprising new and existing units is, as a whole, subject to the Machinery Directive.