THE EUROPEAN PHYSICAL AGENTS (VIBRATION) DIRECTIVE: CAN THE DEMOLITION AND QUARRYING INDUSTRIES COMPLY?

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1 Abstract THE EUROPEAN PHYSICAL AGENTS (VIBRATION) DIRECTIVE: CAN THE DEMOLITION AND QUARRYING INDUSTRIES COMPLY? Neil J Mansfield Department of Human Sciences Loughborough University Loughborough Leicestershire LE11 3TU UK n.j.mansfield@lboro.ac.uk The European Union Physical Agents (Vibration) Directive will, for the first time, introduce legally binding limits on whole-body and hand-transmitted vibration across Europe. Once introduced, employers will have to make risk assessments for each employee. If their exposure exceeds the exposure action value, then a series of actions must be put in place, including ensuring the vibration is reduced as far as possible, health monitoring is introduced and workers are trained. Workers must not be exposed to vibration with a magnitude greater than the limit value. In this paper two industries are considered that will be affected by the whole-body vibration and hand-transmitted vibration action and limit values: quarrying and demolition. Those who work in quarries are likely to be exposed to whole-body vibration that exceeds the action value but not the limit value. Therefore, so long as measures are introduced that are mandated at the action value, workers will still be able to operate the machines for 8-hours per day. Those who use hand tools in the demolition industry are at risk of exceeding the limit value within hours. Therefore, in addition to measures that are mandated at the action value, restriction of tool usage times will be required. 1. Introduction The European Union (EU) currently comprises 15 member states (Figure 1). However, there are an increasing number of eastern European states that have applied to become full members of the EU. All EU states and European Economic Area States need to comply with EU Directives. Many pieces of legislation in force across Europe are derived from European Directives. For example, European member state national regulations relating to manual handling (e.g. the UK Manual Handling Operations Regulations; Her Majesty s Stationery Office, 1992) are an implementation of the European Directive 90/269/EEC (European Commission, 1990). This means that the legislation is similar across Europe, thereby ensuring that workers in each state are equally protected, but also ensuring that industries in one state cannot cut costs by reducing safety standards. Often, EU Directives refer to International or European Standards, therefore giving the standard a legal framework that it would not otherwise have. Directives must be implemented within domestic law by a date specified in the text. Some Directives (e.g. the Physical Agents (Vibration) Directive) allow for slightly alternative forms depending on the preference of the member state. Some can also have a phased implementation according to industrial sector. Such an introduction can occur if there are some sectors that will find it more difficult or expensive to comply than others and these often have a powerful political lobby! Presented at the 11 th Japan Group Meeting on Human Response to Vibration 2003, held in Asahikawa, Japan, July 23 25, 2003.

2 European Union Austria Belgium Denmark Finland France Germany Greece Ireland Italy Luxembourg Netherlands Portugal Spain Sweden United Kingdom European Economic Area European Union + Iceland Liechtenstein Norway Candidate States for EU membership Bulgaria Cyprus Czech Republic Estonia Hungary Latvia Lithuania Malta Poland Romania Slovakia Slovenia Turkey Figure 1. The European Union and European Economic Area within which the Physical Agents (Vibration) Directive will apply. If candidate states complete full integration into the EU, the Directive will also apply in these countries. Currently there are no enforceable limits on human vibration exposure within Europe. However, there is an established premise of case law for claims for compensation due to vibration white finger, including some recent high profile cases for miners and those operating pavement breakers running to many millions of euros. Therefore, employers have needed to take care to follow best practises to minimise the risk for workers and to avoid being considered negligent should a claim arise. After 10 years of drafts and development, the EU Physical Agents (Vibration) Directive was finally published in July 2002 (European Commission, 2002). The Directive must be implemented in the domestic legislature across all European member states. As a result, for the first time, legal limits for acceptable magnitudes of vibration to which a worker can be exposed have been defined. 2. Key points of the Physical Agents (Vibration) Directive As a result of the Physical Agents (Vibration) Directive, affected European States must introduce a legal framework that requires employers to determine and assess risks, reduce exposures to vibration, provide training and consultation with workers and, if a residual risk remains, implement health surveillance. The risk assessment has been the main focus of debate, to date.

3 Table 1. Exposure action values and limit values for hand-transmitted and whole-body vibration as defined in the EU Physical Agents (Vibration) Directive. Hand-transmitted vibration Whole-body vibration Action value 2.5 m/s² A(8) (r.s.s.) 0.5 m/s² A(8) (or 9.1 VDV) (worst axis) Limit value 5.0 m/s² A(8) (r.s.s.) 1.15 m/s² A(8) (or 21 VDV) (worst axis) At the heart of the risk assessment are two quantities, the exposure action value and the exposure limit value. For hand-transmitted vibration, the action value is standardised at 2.5 m/s² A(8) and the limit value is standardised at 5.0 m/s² A(8) for combined vibration in all axes calculated as the root sum of the squares (Table 1). The frequency weighting W h is used for hand-transmitted vibration. The requirements for whole-body vibration are more complex, as the action and limit values are defined in terms of both the VDV and eight hour r.m.s. and each member state can select which to include in domestic law. The action value for whole-body vibration is 0.5 m/s² A(8) or 9.1 VDV; the limit value for whole-body vibration is 1.15 m/s² A(8) or 21 VDV. These quantities are based on the worst axis of vibration only. For horizontal axes, the W d frequency weighting is used as is a multiplying factor of 1.4. For vertical vibration, the W k frequency weighting is used with no additional multiplying factor. In the UK, it is likely that the VDV will be selected for the action value and that the A(8) will be selected for the limit value for whole-body vibration. This will allow for the most effective risk management by using the VDV at the lower threshold, which is considered the better indicator of risk, but allow for flexibility for HSE inspectors by using the A(8) at the higher threshold. Although risk assessments are specified in terms of 8-hour vibration values, it is possible to apply the Directive using a weekly (40 hour) average if the vibration exposures vary substantially from day to day (as might be the case in some industries, such as when using hand tools in demolition). If the action value is exceeded then a risk reduction process must be put in place including minimisation of the vibration related injury risks, minimising exposures and implementing health surveillance (Figure 2). The limit value must not be exceeded. The Physical Agents (Vibration) Directive will be phased in from 6 July 2005 when the action values must be implemented (Figure 3). From 6 July 2007 the limit value must be implemented for all new equipment; all equipment must comply from 6 July However, the agricultural and forestry sectors have a further four years before the limit value must be applied. Sea and air transport can be derogated from the legislation for whole-body vibration, on a case by case basis. As the link between hand-arm vibration and hand arm vibration syndrome is not disputed, one can have some confidence that reducing the vibration magnitudes will reduce the incidence of disease. Despite this, many researchers have reservations with the current assessment methods for hand-arm vibration and believe that better techniques of predicting risk could be developed. If their doubts prove to be correct, then the expected reduction in incidence of disease might not be as marked as hoped. However, any move to reduce the vibration exposure must be welcomed.

4 Eliminate vibration Assess or measure vibration exposure < action value > action value but < limit value Minimise risks Minimise exposure Minimise risks Health surveillance Exposure to vibration yes Can vibration exposure be eliminated? no > limit value Immediate action to reduce exposure below limit value Information and training of workers Regular reviews Figure 2. Action to be taken in response to a risk assessment according to the Physical Agents (Vibration) Directive. It is far more difficult to predict how many fewer workers will develop low back pain after implementation of the Directive. Certainly, whole-body vibration is one risk factor when considering back pain, but many others exist and could still pose a hazard, even if vibration is reduced to below the action value. Assuming a generalised ergonomic approach such that all risk factors are managed (as required in the Physical Agents (Vibration) Directive), a reduction in the incidence of back pain can be expected. However, it will be impossible to determine whether improvements in posture, lifting, vibration or even diet were the main protective factor. Some industries will clearly be affected by the restrictions; indeed, this is a positive outcome of the Directive. If it did not cause individual companies to change their practises, then it could not improve the health of employees. Two example industries are considered that highlight common problems for whole-body vibration and hand-transmitted vibration. Both of these have made considerable efforts to improve the physical environments for their employees since the final drafts of the directive were published. However, the question remains, even with these efforts, will they be able to comply? 3. Case study 1: Whole-body vibration exposures in the quarrying industry For whole-body vibration, problem industries are those where workers are required to drive off road for extended periods of time, where it would be difficult to implement job rotation (due to the lack of other non-vibration affected tasks). One of these industries is quarrying. This section describes vibration exposures for 13 quarrying vehicles working in rock quarries and sand and gravel quarries.

5 Action value Limit value (new equipment) Adoption Limit value (old equipment) Limit value (WBV old equipment agriculture / forestry) (+3 years) (+5 years) (+8 years) (+12 years) Figure 3. Timing of the implementation of the Physical Agents (Vibration) Directive. Vibration measurements were taken at two positions in the cab of each machine. A moulded circular rubber seat pad encasing a tri-axial ICP accelerometer (PCB 356M86) was used to measure the vibration exposure of the driver. The pad was secured to the seat in a central position. A second tri-axial accelerometer also attached securely to the base of the seat frame to allow for an analysis of the effectiveness of the seat at reducing vibration. The accelerometers were connected to two Larson Davis HMV100 meters that conditioned the accelerometers and logged the frequency weighted r.m.s. acceleration each 10 seconds and vibration dose values each three minutes. Each measurement lasted two hours. This section only considers the r.m.s. data for the full two hour measurement. Table 2 shows the summary of r.m.s. values for all of the tested machines. SEAT values are calculated as the ratio of the acceleration at the seat to the acceleration at the floor. The EU Physical Agents (Vibration) Directive specifies that whole-body vibration exposures should be considered in terms of the worst axis of vibration, after the horizontal axes have been scaled by a factor of 1.4 (Table 3). For the articulated dumpers, the worst axis was lateral (y-). For the rigid dumpers the worst axis was vertical (z-). For the loaders, the worst axis was either lateral (y-) or foreand-aft (x-). The telescopic handler and dozer were both dominated by vertical vibration. The Physical Agents (Vibration) Directive defines the exposure action value as a daily A(8) of 0.5 m/s² r.m.s. and the exposure limit value as 1.15 m/s² r.m.s. As no machine exceeded the limit value for these tests, it is possible that the limit value will not be exceeded, so long as workers are not exposed to the vibration for longer than 40 hours per week. However, most machines exceeded the action value; therefore all operators using the machines for extended periods of time will be considered at risk according to the Physical Agents (Vibration) Directive.

6 Table 2 Summary of r.m.s. values for 2 hour duration vibration measurements of vibration exposures for quarrying machines. Machine Seat Floor SEAT value x-axis y-axis z-axis x-axis y-axis z-axis z-axis Articulated Dumper * % Articulated Dumper * % Articulated Dumper * % Rigid Dumper % Rigid Dumper % Rigid Dumper % Front Loader % Face Loader * % Stock Loader * % Face Loader % Stock Loader * % Telescopic Handler * % Dozer * (ripping sand and conglomerate) * Sand and Gravel + Rock % Table 3 Summary of r.m.s. values for 2 hour duration vibration measurements after being scaled in line with the European Physical Agents (Vibration) Directive and the resulting times to the exposure action and limit values. Machine x-axis * 1.4 Seat y-axis * 1.4 z-axis * 1.0 Worst axis Time to action value (hours) Time to limit value (hours) Articulated Dumper * Articulated Dumper * Articulated Dumper * Rigid Dumper >24 hours Rigid Dumper >24 hours Rigid Dumper >24 hours Front Loader >24 hours Face Loader * >24 hours Stock Loader * Face Loader >24 hours Stock Loader * Telescopic Handler * Dozer * (ripping sand and conglomerate) * Sand and Gravel + Rock

7 Therefore, assuming that these measurements are representative of all quarrying machines, the quarrying industry should be able to comply with the Physical Agents (Vibration) Directive, so long as risks (and exposure) are reduced and health surveillance is put in place. Exposure times should be closely monitored to ensure that the limit value is not exceeded. 4. Case study 2: Hand-transmitted vibration exposures in the demolition industry For hand-transmitted vibration, problem industries can be those where there is a continual exposure to moderate magnitudes of vibration or where power tools are used intermittently, but the tools have a very high vibration emission. One such industry is demolition, where hand tools are occasionally used for short periods to complete small tasks. The section describes vibration exposures for 10 demolition tools working on a block of reinforced concrete. Vibration was measured using two Larson Davis HVM100 human vibration meters. Triaxial PCB Piezotronics SEN021F ICP accelerometers were mounted on the handles of the tools using steel clamps. Brüel and Kjær UA0553 mechanical filters were used to minimise the occurrence of overloading the measurement system. Prior to the testing, the accelerometers were calibrated using a Brüel and Kjær 4294 calibrator. Vibration was assessed according to the EU Physical Agents (Vibration) Directive. For all picktype tools, the operator changed grip at the point-end depending on the operation, and often operated the tool only gripping the handle. The change in co-ordinate systems due to grip changes is inconsequential. However, vibration emissions that are not in contact with the body need not be considered when performing a risk assessment. At least three repeat measurements were made of each tool with total combined measurement durations of at least 60 seconds. Results from the measurements are shown in Table 4. All of the tools would exceed the limit value after 8 hours and all would exceed the action value within 2 hours. The most severe tools were the pick type tools (including the mining tool and hammer). The best of these would reach the limit value in 38 minutes; the worst would reach it in less than 10 minutes. The demolition industry will therefore have difficulty in routinely using tools, especially pick type devices when the Directive is fully implemented. It is however possible that some usage of these tools will be allowable, as the directive allows for weekly averaging and these measurements only apply to trigger-on times. Much of the work when using demolition picks involves removing debris and positioning the tool; therefore the actual task time could exceed the limiting trigger-on times substantially. Some demolition tasks could require total redesign. For example, a demolition contractor using a pneumatic pick for long periods might be required, instead, to use a breaker attachment fitted to a mini excavator to eliminate the hand-arm vibration (although in this example there might be knock-on consequences in terms of a new whole-body vibration risk). Of course, it is possible that technological advances in tool design could reduce the vibration magnitudes experienced by the operators, although it is unlikely that any improvements will bring the vibration emissions below the 8-hour limit value.

8 Table 4. Vibration emissions of eight demolition hand tools. Mean vibration magnitude Time to action Tool (worst hand) value (mins) (ms -2 r.m.s.) Time to limit value (mins) Pneumatic breaker Pneumatic pole scabbler Petrol disc cutter Pneumatic demolition pick Pneumatic demolition pick Pneumatic mining tool Pneumatic demolition pick Pneumatic hammer Conclusions When the Physical Agents (Vibration) Directive is enforced, many industries will be affected. It is unlikely that quarrying will exceed the exposure limit value. Therefore, if the industry introduces sufficient risk reduction strategies that are required at the action value, compliance is achievable. The demolition industry will need to take care as it is foreseeable that workers could be exposed to vibration exceeding the limit value, and this will be prohibited. If precautions are taken to ensure that exposure times are carefully controlled, and other risk reduction strategies are introduced (as required at the action value) then compliance is also achievable for the demolition industry. 5. Acknowledgements This research was part funded by the UK National Federation of Demolition Contractors and the UK Quarry Products Association. However, the views expressed in this paper are not necessarily those of the sponsors. 6. References Her Majesty s Stationery Office, Instrument 1992/2793 The manual handling operations regulations. Statutory European Commission, Council Directive on the minimum health and safety requirements for the manual handling of loads where there is a risk particularly of back injury to workers.

9 European Commission, Directive 2002/44/EC of the European Parliament and of the Council of 25 June 2002 on the minimum health and safety requirements regarding the exposure of workers to the risks arising from physical agents (vibration). Official Journal of the European Communities, L177/13.