ISO/TC 108/SC 4 - Human exposure to mechanical vibration and shock

This document specifies methods for determining the uncertainty of the measurement and evaluation of human exposure to vibration. It applies to measurements of vibration quantities (measurands), calculated following a relevant measurement model on the basis of directly measured values, to evaluate a) human exposure to hand-transmitted vibration at the workplace, b) vibration emission of hand-held and hand-guided machinery in a laboratory setting, c) human exposure to whole-body vibration at the workplace, and d) whole-body vibration emission of vehicles. Examples of the application of the individual methods in practical situations are provided in the annexes. In this document a measurement error is defined as the difference between a measured and a reference quantity value. In this document “uncertainty” does not include errors that result from bad measurement strategies, faulty use of measurement equipment or other mistakes.

This document defines specifications covering laboratory tests for seats designed for passengers and crew in railway tractive and trailer vehicles. It concerns tri-axial rectilinear vibration within the frequency range 0,5 Hz to 50 Hz. It specifies the input test vibration to be used at seat testing. This document makes it possible to characterize, in the form of frequency response functions, the manner in which vibration is transmitted to the seat occupant. It also provides an estimator showing the behaviour of the seat in terms of dynamic comfort perceived by the seated person. Different types of excitations can be used and are described depending on knowledge of the vibration environment encountered by the seat and the capability of the vibration simulator.

This document summarizes descriptive quantities for those responsible (e.g. scientists, safety engineers) for determination of postures for a seated person who is exposed to whole-body vibration. It is the intention that the results of different methods can be easily related to these quantities and that they allow for a common terminology between practitioners. The focus of this document is to offer a collection of ideas on how to measure postures in practice. The postures determined can also be used as a basis for further investigation or as a means of comparison for different methods. Although some of the approaches described here can be applied to standing or recumbent positions, additional considerations are likely to be required in these cases. NOTE 1 This work is closely related to International Standards which focus on static postures (ISO 11226[4]) or on radiologically accessible landmarks, i.e. points on the body (ISO 8727[3]). Additionally, this document deals with dynamic postures where body angles or associated movements are determined visually or by measuring points on the skin or clothing. NOTE 2 Nevertheless, ISO 8727[3] and ISO 11226[4] put forward principles for further extensions of posture determination which are followed in this document, in particular for measurements of body angles. This document does not specify sampling strategies or evaluation methods.

This document describes the coupling parameters between the hands of a machine operator and a vibrating surface of the machine. The coupling between the hand and the vibrating surface can be described using different parameters and component parts of these parameters: — force parameters, such as push, pull and grip; — parameters such as pressure exerted on skin. In addition, Annexes A, B, C, D and E provide guidelines for measuring procedures, the measurement of the force and pressure parameters, and information on the requirements for measuring instrumentation, as well as a calibration method. This document does not deal with forces which act tangentially to the hand.

This document specifies methods and procedures for analysing and interpreting vibrotactile perception thresholds and threshold shifts. Procedures for describing statistically significant changes in vibrotactile perception thresholds are recommended. This document is applicable to vibrotactile perception thresholds determined at the fingertips according to the provisions of ISO 13091‑1.

This document describes the range of idealized values of the apparent mass modulus and phase applicable to seated individuals with and without a back support subjected to x-, y- and z‑axis sinusoidal or broad-band random vibration and to standing individuals subjected to z‑axis sinusoidal or broad-band random vibration under specific experimental conditions. Additionally, this document describes the range of idealized values of seat-to-head transmissibility modulus and phase applicable to seated individuals without a back support subjected to z‑axis sinusoidal or broad-band random vibration. The ranges of idealized values defined in this document are considered to be valid for subjects on a rigid seat (or standing on a rigid platform for z-axis only), with feet supported and vibrated. The range of idealized seat-to-head transmissibility values is considered to be applicable also to the condition with the feet hanging freely. For seated individuals subjected to sinusoidal or broad-band random vibration, the apparent mass values are defined over the frequency range of 0,5 Hz to 10 Hz for the x‑axis and y‑axis, and over the frequency range of 0,5 Hz to 20 Hz for the z‑axis. The frequency and amplitude characteristics of the vibration fall within the range for which most vibration exposure is likely to predominate while driving vehicles such as agricultural tractors, earth-moving machinery and fork-lift trucks. Application to automobiles is not covered by this document in view of the lack of a meaningful database for conditions involving posture and vibration excitation levels most likely associated with car driving. The upper and lower values of modulus and phase defined at each frequency for each of the biodynamic response functions considered represent the range of most probable or idealized values. The middle values represent overall weighted means of the human data and define the target values for general applications. Such applications can involve the development of mechanical analogues for laboratory seat testing, or of functions to correct for the human interface when representing the body as a rigid mass, or the development of analytical human body models to be used for whole-body vibration exposure estimations or for seat and cushion design optimization.

This document addresses human exposure to multiple mechanical shocks, and it formulates requirements for the measurement of multiple shocks. The results of these measurements are then analyzed to provide information for the assessment of the risk of adverse health effects to the vertebral end-plates of the lumbar spine for seated individuals due to compression. Other injuries could develop even when there is no injury to the end plate. NOTE 1 Multiple mechanical shocks are shocks of different magnitude and shape that occur frequently at regular and irregular intervals during the measurement period. NOTE 2 As proposed in the annexes, the assessment of the current injury risk is based on measured representative exposures in combination with the individual exposure history. Prospective risks can be assessed by anticipated exposure durations. Manufacturers of measurement equipment are encouraged to develop a possibility for an on-site evaluation of the exposure. Two exposure regimes are distinguished in this document: one for severe conditions and one for less severe conditions. NOTE 3 Clause 4 contains the delineation of the two regimes. This document is applicable for unweighted vertical accelerations that have peak values up to 137,3 m/s2 (14 g) measured at the seat-occupant interface beneath the ischial tuberosities over a 0,01 Hz to 80 Hz measurement bandwidth. NOTE 4 The measurement bandwith is defined in 5.1. Caution is necessary when applying the method to severe exposures, particularly since peak accelerations of 137,3 m/s2 (14 g) are close to the physical limit that a spine can tolerate.

ISO/TR 18570:2017 provides guidance on a supplementary method to that defined in ISO 5349‑1 for measuring and reporting hand-transmitted vibration exposures. The method defined in this document provides an improved assessment methodology for evaluating vascular hand-arm vibration risks (vibration white finger). This document does not apply for other health effects (e.g. sensorineural and musculoskeletal disorders) induced from hand-transmitted vibration exposure (see ISO 5349‑1:2001, Annex Β). ISO/TR 18570:2017 is intended to facilitate future research on hand-arm vibration risks. It can be used to supplement the data given by the ISO 5349‑1 methodology. ISO/TR 18570:2017 cannot be used as an alternative to ISO 5349‑1. Data derived from this document cannot be used in place of ISO 5349‑1 data for fulfilling duties under national regulations, guidance or recommendations for either workplace vibration exposures or machinery vibration emissions. The methodology defined in this document is based on biomechanical and epidemiological studies which are reviewed in Annex A. Also provided in Annex A is tentative information on a relationship between vibration exposure and risk of developing vascular hand-arm vibration disorders.

ISO 10326-1:2016 specifies basic requirements for the laboratory testing of vibration transmission through a vehicle seat to the occupant. These methods for measurement and analysis make it possible to compare test results from different laboratories for equivalent seats. It specifies the test method, the instrumentation requirements, the measuring assessment method and the way to report the test result. ISO 10326-1:2016 applies to specific laboratory seat tests which evaluate vibration transmission to the occupants of any type of seat used in vehicles and mobile off-road machinery. Application standards for specific vehicles refer to this document when defining the test input vibration that is typical for the vibration characteristics of the type or class of vehicle or machinery in which the seat is to be fitted. NOTE Examples of application standards are given in the bibliography.

ISO 14835-1:2016 specifies a) the methods for measuring the finger skin temperature (FST), b) the procedures for conducting the measurements (including the performance of cold provocation tests), and c) how to report the measurement results. The methods specified in this part of ISO 14835 are designed to assist in the collection of basic data for a quantitative evaluation of vascular response to cold provocation, and to enable specification of normative figures. ISO 14835-1:2016 is applicable to the measurement of FST in response to cold provocation for the assessment of various peripheral vascular disorders in persons exposed to hand-arm vibration, and is intended to be used together with a battery of tests for diagnosing hand-arm vibration syndrome.

ISO 10819:2013 specifies a method for the laboratory measurement, data analysis, and reporting of the vibration transmissibility of a glove with a vibration-reducing material that covers the palm, fingers, and thumb of the hand. ISO 10819:2013 specifies vibration transmissibility in terms of vibration transmitted from a handle through a glove to the palm of the hand in one-third-octave frequency bands with centre frequencies of 25 Hz to 1 250 Hz.

ISO 10068:2012 specifies the mechanical impedance of the human male hand-arm system at the driving point. Values of the impedance, expressed as modulus and phase, are provided for three orthogonal, translatory directions of excitation that correspond to the xh-, yh- and zh-axes of the basicentric coordinate system. The xh-, yh- and zh-components of impedance are defined as a function of frequency, from 10 Hz to 500 Hz, for specified arm positions, grip and feed forces, handle diameters, and intensities of excitation. The components of impedance in the three directions are treated as being independent. ISO 10068:2012 can be used to define typical values of the mechanical impedance of the hand-arm system at the driving point, applicable to males under the circumstances specified. ISO 10068:2012 can provisionally be applied to females. Reference values of the mechanical impedance at the driving point are provided as a function of frequency for a specified grip and feed force. These impedance values are intended for the determination of the transmissibility of resilient materials when loaded by the hand-arm system. Mathematical representations of the hand-arm system that model the mean values of apparent mass or impedance are provided. A gloved hand-arm model is described, and the frequency dependence of vibration power absorption in the hand-arm system is also provided. To help conduct further measurement of the mechanical impedance, especially for circumstances that are not specified in ISO 10068:2012, information on the measurement of mechanical impedance is provided.

ISO 14835-2:2005 specifies the methods for measuring finger systolic blood pressures (FSBP) with local cold provocation, the procedures for conducting the measurements, and how to report the measurement results. The methods in ISO 14835-2:2005 are designed to assist in the collection of data for a quantitative evaluation of the vascular response to cold provocation, and to enable specification of normative data. The measurement of FSBP with local cold provocation can be used for the assessment of peripheral vascular function. ISO 14835-2:2005 is applicable to the assessment of vascular function in persons exposed to hand-transmitted vibration.

ISO/TS 15694:2004 specifies methods for measuring single shocks at the handle(s) of hand-held and hand-guided machinery characterized by a maximum strike rate below 5 Hz. ISO/TS 15694:2004 also defines additional requirements for the measuring instrumentation which is necessary for the evaluation of shocks. The aim is to facilitate the gathering of emission and human exposure data in order to provide a basis for emission declaration and for the future development of exposure risk criteria. However, ISO/TS 15694:2004 does not provide methods for the interpretation of the potential human effects of single shocks. It is therefore a basis for measurement and evaluation of emission of single shocks from hand-held and hand-guided machinery but does not cover the evaluation of human exposure.

ISO 2631-2:2003 concerns human exposure to whole-body vibration and shock in buildings with respect to the comfort and annoyance of the occupants. It specifies a method for measurement and evaluation, comprising the determination of the measurement direction and measurement location. It defines the frequency weighting Wm which is applicable in the frequency range 1 Hz to 80 Hz where the posture of an occupant does not need to be defined. Whilst it is often the case that a building will be available for experimental investigation, many of the concepts contained within ISO 2631-2 would apply equally to a building in the design process or where it will not be possible to gain access to an existing building. In these cases, reliance will have to be placed on the prediction of the building response by some means. ISO 2631-2 does not provide guidance on the likelihood of structural damage, which is discussed in ISO 4866. Further, it is not applicable to the evaluation of effects on human health and safety. Acceptable magnitudes of vibration are not stated in ISO 2631-2. The mathematical definition of the frequency weighting Wm is given in Annex A. Guidelines for collecting data concerning complaints about building vibration are given in Annex B.

This part of ISO 2631 provides guidance on the application of ISO 2631-1 to the evaluation of the effects of mechanical vibration on the comfort of passengers and crew in fixed-guideway systems. It is intended to be used by organizations which purchase, specify or use fixed-guideway systems, to help them to understand the relationship between the design of the guideway as well as other features of the system and the comfort of passengers and crew. These guidelines establish methods for the evaluation of relative comfort between systems, as opposed to absolute levels of comfort. This part of ISO 2631 is applicable to people in normal health exposed to rectilinear vibration along their x-, y- and z-axes, as well as rotational vibration about these (body-centred) axes. It is intended to provide guidance on the assessment of comfort as a function of motions along and about vehicle axes that produce the body motions. This part of ISO 2631 is not applicable to high-amplitude single transients which may cause trauma, such as those resulting from vehicle accidents or "run-ins" produced by "longitudinal slack action", nor is it applicable to highamplitude vibration which may affect health. For the purposes of this part of ISO 2631, fixed-guideway passenger systems include rail systems (heavy and light rail), magnetically levitated (MAGLEV) systems and rubber tyre metro-type systems, as well as any of the system types listed above that incorporate a tilt capability to compensate for lateral acceleration when traversing curves. This part of ISO 2631 provides guidance on the effects of very low-frequency accelerations (0,1 Hz to 0,5 Hz) experienced as vertical forces that may cause kinetosis. These forces may be caused by combinations of curve transition, super-elevation and tilt-body technology. However, this part of ISO 2631 is not intended to give guidance on comfort implications of very low-frequency accelerations (below 0,5 Hz) experienced as lateral or longitudinal forces. Such accelerations can be generated by guideway geometry (horizontal alignment and cant). This part of ISO 2631 gives guidance on the evaluation of ride comfort based on motion environment only.

This part of IS0 2631 defines methods for the measurement of periodic, random and transient whole-body
vibration. It indicates the principal factors that combine to determine the degree to which a vibration exposure will
be acceptable. Informative annexes indicate current opinion and provide guidance on the possible effects of
vibration on health, comfort and perception and motion sickness. The frequency range considered is
- 0,5 Hz to 80 Hz for health, comfort and perception, and
- 0,l Hz to 0,5 Hz for motion sickness.
Although the potential effects on human performance are not covered, most of the guidance on whole-body
vibration measurement also applies to this area. This part of IS0 2631 also defines the principles of preferred
methods of mounting transducers for determining human exposure. It does not apply to the evaluation of extrememagnitude single shocks such as occur in vehicle accidents.
This part of IS0 2631 is applicable to motions transmitted to the human body as a whole through the supporting
surfaces: the feet of a standing person, the buttocks, back and feet of a seated person or the supporting area of a
recumbent person. This type of vibration is found in vehicles, in machinery, in buildings and in the vicinity of
working machinery.

Lays down a simple classification of disturbance to human activity and performance by mechanical vibration and shock.

Defines technical aspects of experiments dealing with human or human surrogate testing and procedures for collecting and reporting biomechanical data. Recommended practices regarding measurements, instrumentation and reporting of results are outlined.

Relates to typical responses of people. The recommendations are categorized according to the use and to the nature of work being carried out. Does not deal with the injury of people due to structural vibration. Guidance on satisfactory magnitudes of vibrations for specific situations is given in the annex.

ISO/TR 10687:2012 summarizes descriptive quantities for those responsible (e.g. scientists, safety engineers) for determination of postures for a seated person who is exposed to whole-body vibration. It is the intention that the results of different methods which also are summarized can be easily related to these quantities and that they allow for a common terminology between practitioners. The postures determined can also be used as a basis for further investigation or as a means of comparison for different methods. Although some of the approaches described here can be applied to standing or recumbent positions, additional considerations are likely to be required in these cases. Additionally, ISO/TR 10687:2012 deals with dynamic postures where body angles or associated movements are determined visually or by measuring points on the skin or clothing. ISO/TR 10687:2012 does not recommend sampling strategies or evaluation methods.

ISO 15230:2007 describes the coupling parameters between the hands of a machine operator and a vibrating surface of the machine. The coupling between the hand and the vibrating surface can be described using different parameters and component parts of these parameters: force parameters, such as push, pull and grip; parameters such as pressure exerted on skin. In addition, informative annexes provide guidelines for measuring procedures, the measurement of the force and pressure parameters, and information on the requirements for measuring instrumentation, as well as a calibration method. ISO 15230:2007 does not deal with forces which act tangentially to the hand.

ISO 14835-1:2005 specifies the methods for measuring the finger skin temperature (FST), the procedures for conducting the measurements (including the performance of cold provocation tests), and how to report the measurement results. The methods specified in ISO 14835-1:2005 are designed to assist in the collection of basic data for a quantitative evaluation of vascular response to cold provocation, and to enable specification of normative figures. ISO 14835-1:2005 is applicable to the measurement of FST in response to cold provocation for the assessment of various peripheral vascular disorders in persons exposed to hand-arm vibration, and is intended to be used together with a battery of tests for diagnosing hand-arm vibration syndrome.

ISO 2631-5:2004 addresses human exposure to mechanical multiple shocks measured at the seat pad when a person is seated. The adverse health effects of prolonged exposure to vibration that includes multiple shocks are related to dose measures. The method described in ISO 2631-5:2004 is generally applicable in cases where adverse health effects in the lumbar spine are concerned. The calculation of the lumbar spine response described ISO 2631-5:2004 assumes that the person subjected to the vibration is seated in an upright position and does not voluntarily rise from the seat during the exposure. Different postures can result in different responses in the spine.

ISO 13091-2:2003 specifies methods and procedures for analysing and interpreting vibrotactile perception thresholds and threshold shifts. Procedures for describing statistically significant changes in vibrotactile perception thresholds are recommended. ISO 13091-2:2003 is applicable to vibrotactile perception thresholds determined at the fingertips according to the provisions of ISO 13091-1. Values for the vibrotactile perception thresholds of healthy persons, applicable to thresholds determined according to the provisions of ISO 13091-1, are given in Annex A. The implications of observed changes in vibrotactile perception thresholds are considered in Annex B.

This part of ISO 10326 defines specifications covering laboratory tests for seats designed for passengers and crew in railway tractive and trailer vehicles. It concerns tri-axial rectilinear vibration within the frequency range 0,5 Hz to 50 Hz. It specifies the input test vibration to be used at seat testing. This part of ISO 10326 makes it possible to characterize, in the form of frequency response functions, the manner in which vibration is transmitted to the seat occupant. However, this characterization is fully valid only when the man-seat system can be considered to be sufficiently linear.

Specifies a method for the laboratory measurement, the data analysis and reporting of the vibration transmissibility of gloves in terms of vibration transmission from a handle to the palm of the hand in the frequency range from 31,5 Hz to 1250 Hz.

Specifies the test method, the instrumentation requirements, the measuring assessment method and the way to report the test result.

General guidance is given on human response to building vibrations. Includes weighting curves of frequency response for equal annoyance of humans together with measurement methods to be used. Is concerned only with tactile perception and does not take into account auditory perception of radiated sound.

Standardization is restricted to z-axis vibration for the standing and sitting postures. Currently there is only sufficient information for the head in the frequency range from 0,5 to 31,5 Hz for whole-body vibration entering the torso through the seat or feet.