Minutes of the 4th Construction Hand-arm Vibration Working Group Meeting, HSE, Rose Court, 05/09/06

Attendees: Phil Burgess (HSE), Hans Fairley (Stihl, AEA), Greg Bordiak (BCAS), Peter Alford (JCB), Ulrich Betten (Hilti), Neil Mansfield (Loughborough University, OPERC), Shelly Atkinson-Frost (Construction Confederation), David Smeatham (HSE), Paul Corrigan (Black and Decker/ Dewalt).

The meeting was based around a single agenda item – to discuss potential safeguard action against specific harmonised vibration test codes.

Welcome

Meeting opened and attendees were welcomed. Members of the group introduced themselves and stated whom they were representing.

Background to safeguard action

During the last working group meeting in Manchester (30 th May 2006) the group discussed the relative merits of tools tested to provide data representative of the upper quartile vibration of in use applications and in-use tests whilst tools performed specific tasks. As a unanimous way forward was not achieved, further consultation within HSE was sought. During this consultation it was suggested that the revision of the traffic light system could be seen as a barrier to trade. HSE arranged a meeting with the DTI (the government body responsible for the Machinery Directive) to discuss the work of the working group. During the meeting HSE explained the need for the initiative in terms of the goals set by the working group. The DTI concurred with need for the work.

As it stands there is a presumption of conformity if a manufacturer declares information in accordance with the harmonised standards. Many of the harmonised standards do not provide vibration information that will enable safe use of the machine (i.e. single axis vibration measurement, single hand measurement and in some cases unrealistic operating conditions). It is recognised that these standards were written in good faith and work is currently underway to re-address these issues. To take this forward the DTI suggested that a safeguard action is prepared for their consideration with the potential to submit it to the EU with regard to the current standards. Any such action, if progressed, would be supported by a proposal for guidance on the declaration of vibration information to cover the period until the new standards are agreed. If the EU accepted the safeguard action and the guidance agreed it would seek to level the playing field for relevant tool supply issues in the EU, irrespective of their origin.

Discussion of target tools and where safeguard action is thought to be needed

Target tools in the construction industry have been discussed and agreed during the working group meetings. The need for safeguard action with respect to each of these tools was discussed. The results were:

• Cut-off machines – Current standard requires three axes measurements whilst tool is fitted with an unbalanced wheel. Hans Fairley confirmed that the standard test provides data comparable with the vibration during real use for some applications.
• Compaction machines – There is no standard test method for these tools and the industry is working towards a standard test application. OPERC are assisting in this area and have some comparative data on typical applications of the machines. There are no barriers to trade issues because of the lack of a harmonised standard.
• Jigger picks/Chipping hammers – EN ISO 8662-2. This standard requires single axis measurement on the rear handle only. The move to three axes in the Control of Vibration at Work Regulations and the fact the in many circumstances the highest vibration is measured at the front hand position mean that the vibration emission declared often underestimates the risk. – Safe guard action proposed.
• Breakers (can include jigger picks also) – EN ISO 8226-5. This standard requires a single axis measurement at one hand position. Modern tools often incorporate vibration reduction techniques that introduce significant vibration in the lateral axes and there is a need for residual risk information to enable end-users to use the tool safely (e.g. the need for training on push forces and operator technique). Safe guard action proposed.
• Demo hammers and Combi hammers – EN 60745. This is a new standard produced to satisfy the requirements of EN 20643 (i.e. designed to produce the upper quartile vibration). Verification of the standard is needed to ensure the information is suitable for an initial risk assessment. No safeguard action proposed.
• Scabblers and needle scallers – EN ISO 8662-14. it was proposed that this should be included in the safeguard action as it shares many of the problems highlighted in EN ISO 8662-2 and EN ISO 8662-5.

Discussion of supporting guidance.

If the safeguard action were successful, guidance would need to be produced to enable tool manufacturers and supplies to declare vibration during the period up to the acceptance of a new vibration test code. Potential methods were proposed.

• Convert the existing test codes to three axes two hand versions whilst maintaining the same operating conditions of the tool as specified in the current standard. In addition, provide another clause in the temporary guidance to say that the residual risk requirements of the Machinery Directive also apply. This would require manufacturers and suppliers of machine to provide information on the safe use of the tool (e.g. the need for training to enable the tool to be used safely with respect to vibration, maintenance and where needed an indication of the vibration in-use if that was significantly different to the declared value).
• Use existing single-axis standards in conjunction with multiplying factors provided in CEN/TR 15350 to convert the data to equivalent three axes in-use data. It was stated that some of the multiplying factors contained in this report were very low and will therefore underestimate the risk of the tool use (e.g. grinders). The multiplying factors for the tool categories in question would need to be investigated.
• Use a combination of three axes measurements and CEN/TR 15350 multiplying factors.

In general the group were supportive of the proposed safeguard action. A concern was raised regarding the potential confusion caused by the availability of another type of vibration information. The point was made that the possibility of confusion would be reduced because the appropriate data would be combined and brought together for the construction industry in one place hopefully avoiding confusion.

Actions

D Smeatham

• Prepare draft safeguard actions for the three standards highlighted and circulate to the group for comment
• Prepare draft proposal for supporting guidance

AOB

The next group meeting will be 29 th September in HSE’s Leeds office. The group will split into two (one group discussing vibration data and the proposed safeguard action the other group taking forward the development of HAVS management system – e.g. hierarchy of control, health surveillance etc). The meeting will conclude with a plenary session. An agenda with directions will be circulated before the meeting.