BS EN 13128 is the safety standard for milling machines. Jon Severn, Editor of MachineBuilding.net, reviews the standard to see what it contains and how it might help machine builders.
British standard BS EN 13128:2001 +A2:2009, Safety of machine tools – Milling machines (including boring machines), is the British equivalent of European standard EN 12128, a Type C standard that is harmonised to the Machinery Directive 2006/42/EC. The latest version incorporates the March 2010 corrigendum relating to uncertainty in sound power measurements for use in the Noise Declaration.
The milling machine safety standard covers all types of milling and boring machines, plus workpiece transfer devices, but milling machines with automatic tool changing capabilities are covered by BS EN 12417:2001+A2:2009, Machine tools. Safety. Machining centres (the standard actually refers to prEN 12417:1996, but this has since been superseded).
Although the standard states that it does not relate to machines manufactured prior to the date of publication of the standard, companies that remanufacture milling machines or upgrade milling machines by, for example, retrofitting CNC controls, should note that such actions may require the machine to be CE marked in accordance with the Machinery Directive 2006/42/EC, in which case compliance with the relevant harmonised standards provides a presumption of conformity and is, therefore, the easiest way to demonstrate compliance with the Essential Health and Safety Requirements of the Directive.
Anyone using BS EN 13128 should also look closely at Clause 2, Normative references, which runs to approximately two pages and lists some 40 other standards that are cited and may therefore need to be consulted.
Hazards and safety measures
Arguably the most useful Clauses in BS EN 13128 are 4, List of significant hazards, and 5, Safety requirements and/or protective measures. The core information in these clauses is presented in tabular format. In Clause 4, Table 1 lists significant hazards and major sources of these hazards. For each hazard there is a description, example(s) of related hazardous situation(s), associated activity, related danger zone and a cross-reference to the relevant Clause in the standard.
In Clause 5, Tables 2, 3, 4 and 5 list safety requirements and/or protective measures and their verification procedures. The four tables relate to different machine types and hazards as follows:
- Table 2 – Manual machines with continuous powered axis feedrates not exceeding 2m/min and/or a hold-to-run controlled rapid travserse axis speed not exceeding 5m/min.
- Table 3 – Manual machines with continuous powered axis speeds in excess of 2m/min or hold-to-run controlled rapid travserse axis speed in excess of 5m/min.
- Table 4 – Automatic machines (mechanical hazards).
- Table 5 – Manual and automatic machines (hazards other that those listed in tables 2, 3 and 4).
Clause 6 and 7 cover, respectively, Verification of safety requirements and/or measures and Information for use.
In addition to the main body of BS EN 13128, there are several annexes. Annex A, which is normative rather than informative, describes an impact test method for milling machine guards. Annex B, which is informative only, describes equipment for performing impact tests. Annex C, also informative, provides simple line drawings to illustrate different types of milling machines and guards. Annex D (informative) describes noise emission measurements. Annexes ZA and ZB state the relationship between the European standard and, respectively, the old and new Machinery Directives.
BS EN 13128:2001 +A2:2009, ISBN 978 0 580 66924 8, is available from BSI as a PDF or hard copy priced £182 (or £91 for Members of BSI). Follow the link to see more about BS EN 13128:2001 +A2:2009.