EN 14253:2003+A1:2007

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Mechanische Schwingungen - Messung und rechnerische Ermittlung der Einwirkung von Ganzkörper-Schwingungen auf den Menschen am Arbeitsplatz im Hinblick auf seine Gesundheit - Praxisgerechte AnleitungVibrations mécaniques - Mesurage et calcul de l'effet sur la santé de l'exposition professionnelle aux vibrations transmises à l'ensemble du corps - Guide pratiqueMechanical vibration - Measurement and calculation of occupational exposure to whole-body vibration with reference to health - Practical guidance13.160Vpliv vibracij in udarcev na ljudiVibration and shock with respect to human beingsICS:Ta slovenski standard je istoveten z:EN 14253:2003+A1:2007SIST EN 14253:2004+A1:2009en,fr,de01-februar-2009SIST EN 14253:2004+A1:2009SLOVENSKI
STANDARD
EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM
EN 14253:2003+A1
November 2007 ICS 13.160 Supersedes EN 14253:2003 English Version
Mechanical vibration - Measurement and calculation of occupational exposure to whole-body vibration with reference to health - Practical guidance
Vibrations mécaniques - Mesurage et calcul de l'effet sur la santé de l'exposition professionnelle aux vibrations transmises à l'ensemble du corps - Guide pratique
Mechanische Schwingungen - Messung und rechnerische Ermittlung der Einwirkung von Ganzkörper-Schwingungen auf den Menschen am Arbeitsplatz im Hinblick auf seine Gesundheit - Praxisgerechte Anleitung This European Standard was approved by CEN on 1 September 2003 and includes Amendment 1 approved by CEN on 21 October 2007.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN Management Centre or to any CEN member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
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B-1050 Brussels © 2007 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 14253:2003+A1:2007: ESIST EN 14253:2004+A1:2009

Examples of the calculation of daily vibration exposure.17 Annex B (informative)
Some numerical examples of the determination of daily vibration exposure.19 Annex C (informative)
!!!!Guidance on handling of transient acceleration artefacts due to intentional operator movements.21 Bibliography.24 SIST EN 14253:2004+A1:2009

is the frequency-weighted r.m.s. value of the acceleration, determined over the time period Ti kx = ky = 1,4 for the x- and y-directions; kz = 1 for the z-direction l = x, y, z T0
is the reference duration of 8 h (28800 s) NOTE 1 The Physical Agents Directive 2002/44/EC allows an 8-h vibration dose value (VDV) instead of A(8). Where VDV is used, the Al(8) in this European Standard should be replaced by the daily vibration dose value in the l direction. The use of VDV instead of A(8) will generally result in a different evaluation of the health risk. NOTE 2 The values of kl in the x- and y-directions are based on sensitivity of seated persons but the same factors should be applied for other postures, e.g. standing. NOTE 3 If it can be shown that there is clearly a dominant direction it is sufficient to measure only this direction. The individual contribution of an operation or work cycle i to the daily vibration exposure can be calculated as: 0)8(TTakAiwlilli= (2) 5 Preparation of the measurement procedure 5.1 General The vibration exposure of an individual during a working day may involve a series of different operations, some of which may be repeated. The vibration exposure may vary greatly from one operation to another, e.g. due to the operator’s behaviour, the use of different machines or differences between the operations, or due to seasonal effects. Before making measurements, it is first necessary to identify the individual operations which are likely to contribute substantially to the overall exposure. The location and nature of each operation should be defined accurately and the total duration associated with the individual worker during the single day should be quantified. A survey should be undertaken to establish an “exposure profile”. This will help to determine the likely relative importance of each type of operation in the overall value of A(8), to identify those for which measurements are required, and to assist in the planning of any necessary exposure controls. The daily vibration exposure A(8) may be determined for a specific individual on a specific day. In some situations it may also be useful to calculate A(8) for a notional “typical” day’s exposure, using carefully selected representative vibration measurements and carefully considered exposure duration values. There is no method for evaluating the SIST EN 14253:2004+A1:2009

EXAMPLE  speed of mobile machines;  a fork-lift truck may be travelling on a smooth surface inside a building, on an uneven surface inside (pits, thresholds, cables/hoses, debris, etc.) or on a rough surface outside;  a dumper may be travelling unloaded or loaded;  additional equipment which might affect vibration exposure, e.g. an agricultural tractor may be fitted with a slurry tanker or a plough. In addition, it may be useful to obtain:  information from workers and supervisors on which operations they believe produce the highest vibration magnitude;  estimates of the potential vibration hazards for each operation, using information from manufacturers on vibration emission values, or using published results of previous measurements on similar machines;  manufacturers’ information on vibration magnitudes and the travelling conditions under which they have been measured;  subject's posture, seat suspension topping or bottoming, use of backrest. In the case of short, well-defined exposures, different vibration magnitudes may be associated with each of the individual operations (e.g. loading and travelling over a rough surface with a wheel-loader, travelling and lifting with a fork-lift truck). In such cases, as many measurements as practicable should be performed for each individual SIST EN 14253:2004+A1:2009

In addition to vibration magnitude information, the evaluation of daily vibration exposure requires a determination of the duration of exposure to vibration per day. b) The daily work consists of operations with different vibration magnitudes over short periods in respect to the daily working times (e.g. loading and travelling over a rough surface with a wheel-loader, travelling and lifting with a fork-lift truck). In such cases either the measurements are made separately for each of the different operations at the whole work and the results are combined or where the combination of operation duration is available the measurements are made directly for this combination. In addition to vibration magnitude information, the evaluation of daily vibration exposure requires a determination of the exposure duration associated with each operation. Separate measurements shall be made during those operations believed to cause the greatest vibration magnitudes in order to establish the highest short-term exposure. When identifying the important operations, it is important to consider events which occur outside the main work. For example, driving an agricultural tractor to and from the field may result in more vibration than the operation undertaken in the field. 5.4 Duration and number of vibration measurements The duration and number of measurements shall be selected so that a representative 8 h frequency-weighted vibration value can be established. Where continuous measurement throughout the day is not possible, the duration of measurements will be determined by the operation characteristics defined in 5.2. a) Where the daily work consists of long uninterrupted operations, a series of sample measurements, each of at least 3 min duration, should be taken at different times of the day, and averaged so that variations in vibration through the day are accounted for. The number, N, of sample measurements made shall be sufficient to show that the average value obtained is representative of the vibration occurring throughout the day. SIST EN 14253:2004+A1:2009

∑==NjjtT1 is the total measurement duration This procedure shall be carried out separately for vibration in each of the axes measured. b) Where the daily work consists of operations of shorter duration, which are repeated several times during a working day, measurements for determination of the 8 h energy-equivalent vibration value can be made over complete work cycles. The number of work cycles over which measurements are made shall be sufficient to show that the average value obtained is representative of the vibration from the operation throughout the day. c) Where no operations are repeated, the vibration from every operation shall be measured. d) Where there is no repeated work cycle of operations of short duration and the individual operations are shorter than 3 min, the operations can be repeated in order to collect measurements over a minimum of 3 min, see example in clause A.3. As an alternative, simulated operations may be organized for making measurements of 3 min duration. NOTE The requirement of a minimum of 3 min is due to statistical reasons. 5.5 Estimation of exposure time The total daily exposure duration shall be obtained for each operation or work cycle for which a vibration magnitude has been established. This may be based on; a) a measurement of the actual exposure duration of a single operation or work cycle; and b) information on the number of operations or work cycles per working day. The first of these will be a measurement to determine how long an operator is exposed to vibration, and from what source, during a specified period. Various techniques may be used, for example:  use of a stopwatch;  analysis of video recordings;  activity sampling. A source of information may be work records, e.g. the number of lorries loaded and unloaded by fork-lift trucks. However, it is important to ensure that the information is compatible with the information required for an evaluation of daily vibration exposure. For example, work records might give very accurate information on the number of completed work items at the end of each day, but where there is more than one operator, or unfinished work items at the end of a shift, this information may not be directly applicable to a vibration exposure evaluation. NOTE Operators asked for information on their typical daily vibration exposure duration will normally give an estimate which includes periods of time when there is no vibration (e.g. idling, lifting for a fork-lift truck). Therefore, such an approach often results in an overestimation of the exposure duration. SIST EN 14253:2004+A1:2009

6.1 Measuring equipment 6.1.1 General Vibration measurement systems generally use accelerometers to detect the motion of the vibrating surface. Measurement systems shall be checked before and after measurements. Calibrated measurement systems shall be used. Vibration measurements may be made using simple single-unit vibration meters featuring built-in frequency weightings and integrating facilities. These systems are designed primarily to evaluate the vibration exposure at the workplace; they are generally sufficient for most situations covered by this European Standard. More sophisticated measurement systems are often based around some form of frequency analysis, (e.g. narrow band or one-third-octave bands); they may use digital or analogue data recorders to store time information. They may use computer-based data acquisition and analysis techniques. These systems are more costly and complex to operate than the single-unit systems. Frequency analysis will provide information on any dominant frequencies and harmonics which may help to identify effective vibration control measures. Where there is any doubt about the quality of the acceleration signal, it is useful to inspect the acceleration time history. Measuring and analysing equipment shall meet the requirements of !EN ISO 8041", which specifies minimum performance requirements (e.g. frequency weighting characteristics, tolerances, dynamic range, sensitivity, linearity and overload capacity) for appropriate measuring and analysing equipment.
!This" instrumentation can normally be used for evaluation of human exposure. 6.1.2 Accelerometers 6.1.2.1 General Accelerometers shall normally be used for measurement of vibration. In general, the choice of accelerometer will be defined by the expected vibration magnitude, the required frequency range, the physical characteristics of the surface being measured and the environment in which they are to be used. 6.1.2.2 Vibration magnitude The accelerometers chosen for the measurement shall be able to operate at the greatest acceleration magnitudes expected and have a suitable dynamic range to cope with smaller magnitudes at low frequencies. If the accelerometer responds at zero Hertz (e.g. piezoresistive accelerometers) the dynamic range shall be sufficient to accommodate both the gravitational component and the vibration. 6.1.2.3 Environmental conditions Accelerometer’s sensitivity to temperature, humidity and other environmental factors shall be considered (see !EN ISO 8041"). 6.1.3 Location and mounting of accelerometers 6.1.3.1 General Accelerometers shall be located so as to indicate the vibration at the interface between the human body and the source of vibration.
NOTE There is no need to attach the disc on the seat since the fixing due to the operator mass is adequate in the range of frequencies being measured. Nevertheless the disc may be maintained in
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