SIST-TS CEN ISO/TS 15694:2004

SLOVENSKI STANDARD
SIST-TS CEN ISO/TS 15694:2004
01-september-2004
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Mechanical vibration and shock - Measurement and evaluation of single shocks
transmitted from hand-held and hand-guided machines to the hand-arm system (ISO/TS
15694:2004)
Mechanische Schwingungen und Stöße - Messung und Bewertung diskreter Stöße, die
von handgehaltenen und handgeführten Maschinen auf das Hand-Arm-System
übertragen erden (ISO/TS 15694:2004)
Vibrations et chocs mécaniques - Mesurage et évaluation des chocs simples transmis
par les machines portatives et guidées a la main au systeme main bras (ISO/TS
15694:2004)
Ta slovenski standard je istoveten z: CEN ISO/TS 15694:2004
ICS:
13.160 Vpliv vibracij in udarcev na Vibration and shock with
ljudi respect to human beings
SIST-TS CEN ISO/TS 15694:2004 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST-TS CEN ISO/TS 15694:2004

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SIST-TS CEN ISO/TS 15694:2004
TECHNICAL SPECIFICATION
CEN ISO/TS 15694
SPÉCIFICATION TECHNIQUE
TECHNISCHE SPEZIFIKATION
April 2004
ICS 13.160
English version
Mechanical vibration and shock - Measurement and evaluation
of single shocks transmitted from hand-held and hand-guided
machines to the hand-arm system (ISO/TS 15694:2004)
Vibrations et chocs mécaniques - Mesurage et évaluation Mechanische Schwingungen und Stöße - Messung und
des chocs simples transmis par les machines portatives et Bewertung diskreter Stöße, die von handgehaltenen und
guidées à la main au système main bras (ISO/TS handgeführten Maschinen auf das Hand-Arm-System
15694:2004) übertragen erden (ISO/TS 15694:2004)
This Technical Specification (CEN/TS) was approved by CEN on 5 October 2003 for provisional application.
The period of validity of this CEN/TS is limited initially to three years. After two years the members of CEN will be requested to submit their
comments, particularly on the question whether the CEN/TS can be converted into a European Standard.
CEN members are required to announce the existence of this CEN/TS in the same way as for an EN and to make the CEN/TS available
promptly at national level in an appropriate form. It is permissible to keep conflicting national standards in force (in parallel to the CEN/TS)
until the final decision about the possible conversion of the CEN/TS into an EN is reached.
CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,
Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia,
Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2004 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN ISO/TS 15694:2004: E
worldwide for CEN national Members.

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SIST-TS CEN ISO/TS 15694:2004
CEN ISO/TS 15694:2004(E)
Contents
page
Foreword.3
Introduction .4
1 Scope .5
2 Normative references .5
3 Terms and definitions .5
4 Parameters for describing single shocks .6
4.1 Acceleration .6
4.2 Flat -weighted acceleration.6
h
4.3 Root-mean-square value of flat -weighted acceleration .6
h
4.4 Running root-mean-square value of flat -weighted acceleration.7
h
4.5 Root-mean-quad value of flat -weighted acceleration .7
h
4.6 Maximum transient vibration value of flat -weighted acceleration.7
h
4.7 Peak value of flat -weighted acceleration.8
h
4.8 Crest factor of flat -weighted acceleration .8
h
4.9 Shock content quotient of flat -weighted acceleration .8
h
4.10 W -weighted acceleration .8
h
4.11 Root-mean-square value of W -weighted acceleration.9
h
4.12 Root-mean-quad value of W -weighted acceleration.9
h
4.13 Shock content quotient of W -weighted acceleration.9
h
5 Measuring instrumentation.9
6 Measurement procedure .10
6.1 Attaching accelerometers.10
6.2 Orientation of accelerometers.10
6.3 Working procedure.10
7 Measurement report .10
Annex A (normative) Requirements and test methods for the measuring instrumentation .12
Annex B (informative) Recommendations and test methods for a digital measuring instrumentation.15
Annex C (informative) Alternative parameter to describe single shocks.17
Annex D (normative) Filter for flat frequency weighting .18
h
Annex E (normative) Filter for frequency weighting W from EN ISO 5349-1 .20
h
Bibliography .22
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Foreword
This document (CEN ISO/TS 15694:2004) has been prepared by Technical Committee CEN/TC 231 "Mechanical
vibration and shock", the secretariat of which is held by DIN, in collaboration with Technical Committee ISO/TC 108
"Mechanical vibration and shock".
Annexes A, D and E are normative, Annexes B and C are informative.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to announce this CEN Technical Specification: Austria, Belgium, Cyprus, Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and
United Kingdom
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Introduction
The effects of repeated shock-type excitations on the hand-arm system are not fully understood. A literature review
([5], [9] and [11]) shows that there is insufficient knowledge to establish whether the methods from EN ISO 5349-1
can be used for the assessment of health risks from shock-type loading of the hand and arm.
In spite of the lack of knowledge in this field, it is desirable to standardise methods for describing shock-type
excitation from hand-held and hand-guided machinery. The purpose of this Technical Specification is to define
methods
 for gathering consistent data on hand-transmitted single shocks under closely defined conditions and
according to uniform criteria and
 for providing information on the shock emission of a given power tool, allowing an objective comparison of
different power tools.
Power tools causing shock-type exposure are, for example, nailers, tackers, staplers and setting tools. Impact
wrenches and nut runners are not included because it is not usually possible to trigger a single shock for these
power tools.
Methods for the interpretation of the potential human effects of single shocks would be desirable but the lack of
knowledge does not, at present, allow for the inclusion of such methods in a standard; in the future it is expected
that these areas will be included.
The specification for instrumentation in ENV 28041 does not adequately describe the phase response, or the flat
frequency response, for measurement of single shocks.
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1 Scope
This Technical Specification specifies methods for measuring single shocks at the handle(s) of hand-held and
hand-guided machinery characterised by a maximum strike rate below 5 Hz.
NOTE In order to describe the characteristics of single shocks, this Technical Specification defines quantities for the
evaluation which go beyond those defined for hand-transmitted vibration in EN ISO 5349-1.
This Technical Specification also defines additional requirements for the measuring instrumentation which is
necessary for the evaluation of shocks (see Annexes A, B, D and E).
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, this Technical Specification does not
provide methods for the interpretation of the potential human effects of single shocks.
This Technical Specification therefore is 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.
2 Normative references
This Technical Specification incorporates by dated or undated reference, provisions from other publications. These
normative references are cited at the appropriate places in the text and the publications are listed hereafter. For
dated references, subsequent amendments to or revisions of any of these publications apply to this Technical
Specification only when incorporated in it by amendment or revision. For undated references the latest edition of
the publication referred to applies (including amendments).
EN 1033, Hand-arm vibration — Laboratory measurement of vibration at the grip surface of hand-guided machinery
— General
ENV 28041, Human response to vibration — Measuring instrumentation (ISO 8041:1990)
EN ISO 5349-1:2001, Mechanical vibration — Measurement and evaluation of human exposure to hand-
transmitted vibration — Part 1: General requirements (ISO 5349-1:2001)
EN ISO 5349-2, Mechanical vibration — Measurement and evaluation of human exposure to hand-transmitted
vibration — Part 2: Practical guidance for measurement at the workplace (ISO 5349-2:2001)
CEN ISO/TS 8662-11, Hand-held portable power tools — Measurement of vibrations at the handle — Part 11:
Fastener driving tools (nailers) (ISO 8662-11:1999 + Amd. 1:2001)
ISO 5348, Mechanical vibration and shock — Mechanical mounting of accelerometers
3 Terms and definitions
For the purposes of this Technical Specification, the symbols given in EN ISO 5349-1 and the terms and definitions
given in EN ISO 5349-2 and the following apply.
3.1
single shock
short burst of acceleration
NOTE 1 The acceleration time history of a single shock includes a rise to a peak value (see 4.7), followed by a decay of the
acceleration envelope.
NOTE 2 In principle a single shock could also be defined by other physical quantities, for example force or mechanical power
transmitted to the hand-arm system. Due to practical measurement considerations, however, the restricted definition in terms of
acceleration is used (see also Annex C).
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EXAMPLE Power tools causing single shocks or single-shock vibration are nailers, tackers, staplers, setting tools, etc.
These power tools produce a burst of high acceleration with short duration (e.g. 10 ms). The period between two shocks is
much longer than the shock itself (e.g. greater than 200 ms).
3.2
single-shock vibration
series of single shocks separated by periods of zero acceleration
EXAMPLE See example in 3.1.
3.3
repetition time
T
rep
time interval between two consecutive single shocks
3.4
strike rate
f
0
for constant repetition time , the reciprocal of the repetition time, i.e. = 1/
T f T
rep 0 rep
3.5
flat
h
designation for unweighted acceleration which is band-limited as specified in 4.2 and Annex D
4 Parameters for describing single shocks
4.1 Acceleration
a t
The basic quantity for describing single shocks is the acceleration ( ) . It is the basis of all parameters used in this
Technical Specification.
NOTE For use of the vibration velocity to describe single shocks, see Annex C.
4.2 Flat -weighted acceleration
h
The flat -weighted acceleration a (t) is the band-limited acceleration in the frequency band from 6,3 Hz to
h
hF
1250 Hz. The filter for the flat weighting is specified in Annex D.
h
NOTE 1 This frequency band corresponds to the octave bands from 8 Hz to 1000 Hz. In some cases a wider pass band is
required; variations should then be reported with the measurement values.
NOTE 2 The flat weighting differs from the flat responses often provided on measuring instrumentation by a clearly defined
h
frequency band and phase response.
NOTE 3 Unweighted acceleration in this Technical Specification means band-limited acceleration in the frequency band with
a low-pass corner frequency greater than 1250 Hz.
4.3 Root-mean-square value of flat -weighted acceleration
h
Using the specification in 4.2 the root-mean-square (r.m.s.) value of a (t) in a time interval T is given by
hF
T
1
2
a = a (t) dt (1)
hF,RMS,T
∫ hF
T
0
It describes the energy-equivalent average value of the signal. A prescribed fixed integration time of T = 3 s
allows comparison of various measurement results and helps the tool operator to achieve reproducibility.
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Experience shows that T = 3 s is a good compromise between the reaction time of the operator and the
requirement for shortest practicable integration time. In order to increase the confidence level of the results it is
advisable to take the average of this quantity over a series of single shocks (see 6.3).
4.4 Running root-mean-square value of flat -weighted acceleration
h
Using the specification in 4.2 the running root-mean-square value of a (t) at time of observation, t , is given by
hF
t-xt
-
1
2t
a (t) = a (x) e dx(2)
hF,RRMS,t∫ hF
t
0
where
t is the time of observation (actual time)
xis the integration variable
tis a time constant which is to be specified. A time constant t = 0,125 s is preferred.
In order to increase the confidence level of the results it is advisable to take the average of this quantity over a
series of single shocks (see 6.3).
NOTE 1 The exponential averaging function describes the behaviour of many natural processes. It can be generated by very
simple analogue or digital signal processing. The true running r.m.s. acceleration value, obtained by linear integration over a
running time interval of fixed length, looks simpler mathematically but would, in reality, be more difficult to achieve with analogue
instrumentation without any advantage.
NOTE 2 Other International Standards prefer the linear averaging for the running root-mean-square value, which is defined
as follows:
t
1
2
a (t) = a (x) dx
hF,RRMS,thF
∫
t
0
4.5 Root-mean-quad value of flat -weighted acceleration
h
Using the specification in 4.2 the root-mean-quad (r.m.q.) value of a (t) in a time interval T is given by
hF
T
1
4
a = 4 a (t) dt (3)
hF,RMQ,T
∫ hF
T
0
As with the root-mean-square value in 4.3 it describes an average value of the signal. However, with the r.m.q.
average the influence of the higher magnitudes is stronger than with the r.m.s. A prescribed fixed integration time of
T = 3 s allows comparison of various measurement results and helps the tool operator to achieve reproducibility.
Experience shows that T = 3 s is a good compromise between the reaction time of the operator and the
requirement for shortest practicable integration time. In order to increase the confidence level of the results it is
advisable to take the average of this quantity over a series of single shocks (see 6.3).
4.6 Maximum transient vibration value of flat -weighted acceleration
h
Using the specifications in 4.4 the maximum transient vibration value (MTVV) in the time interval T is the highest
a (t) as given by
magnitude of
hF ,RRMS ,t
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a = max{}ta (t) (4)
hF,MTVV,thF,RRMS,
0£t£T
th
In order to increase the confidence level of the results it is advisable to take the 50 percentile of this quantity over
a series of single shocks.
4.7 Peak value of flat -weighted acceleration
h
For any specified time interval 0£t£T , the peak value (PV) of a (t) is the maximum absolute instantaneous
hF
value, as given by
{}
a = max a (t) (5)
hF,PV hF
0£t£T
This quantity is used to describe the top level of the signal. In order to increase the confidence level of the results it
th
is advisable to take the 50 percentile of this quantity over a series of single shocks.
4.8 Crest factor of flat -weighted acceleration
h
Using the quantities in 4.3 and 4.7 the crest factor of the flat -weighted acceleration, CF , is obtained by dividing
h h
the peak value of flat -weighted acceleration by the root-mean-square value of the flat -weighted acceleration
h h
measured in the same time period T:
a
hF,PV
(6)
CF =
h
a
hF,RMS,T
This quantity combines the peak value of the signal with the energy-equivalent r.m.s. value and therefore describes
the impulsiveness of the flat -weighted signal.
h
4.9 Shock content quotient of flat -weighted acceleration
h
Using the quantities in 4.3 and 4.5 the shock content quotient of the flat -weighted acceleration, SC , is obtained by
h h
dividing the root-mean-quad value of the flat -weighted acceleration by the root-mean-square value of the flat -
h h
weighted acceleration measured in the same time period T:
a
hF,RMQ,T
SC = (7)
h
a
hF,RMS,T
This quantity also describes the impulsiveness of the signal.
4.10 W -weighted acceleration
h
The frequency weighting characteristic W , used for the measurement and evaluation of hand-transmitted vibration,
h
is defined in EN ISO 5349-1 and is precisely specified in Annex E. W -weighted acceleration is denoted by a (t) .
h
hw
NOTE 1 a (t) may be derived from a (t) (see 4.2) by applying an acceleration-velocity transition function (a-v-
hw hF
transition) which converts acceleration into velocity for frequencies above 16 Hz.
NOTE 2 Although the frequency weighting in EN ISO 5349-1 was originally defined in order to assess periodic and random
or non-periodic vibration, EN ISO 5349-1:2001 states that it may provisionally "also be applied to repeated shock type excitation
(impact)." In addition, use of the W frequency weighting allows comparison with existing data. Furthermore, measurements of
h
parameters based on a (t) can be more reproducible, because problematic higher-frequency components are attenuated.
hw
The order of presentation chosen in this Technical Specification (flat weighting, followed by W weighting) does not imply that
h h
the former is preferred.
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4.11 Root-mean-square value of W -weighted acceleration
h
Using the specification in 4.10 the root-mean-square value of a (t) in a time interval T is given by
hw
T
1
2
a = a (t) dt (8)
hw,RMS,T
∫ hw
T
0
It describes the energy-equivalent average value of the signal. A prescribed fixed integration time of T = 3 s
allows comparison of various measurement results and helps the tool operator to achieve reproducibility.
Experience shows that T = 3 s is a good compromise between the reaction time of the operator and the
requirement for shortest practicable integration time. In order to increase the confidence level of the results it is
advisable to take the average of this quantity over a series of single shocks (see 6.3).
4.12 Root-mean-quad value of W -weighted acceleration
h
Using the specification in 4.10 the root-mean-quad value of a (t) in a time interval T is given by
hw
T
1
4
a = 4 a (t) dt (9)
hw,RMQ,T hw
∫
T
0
As with the root-mean-square value in 4.11 it describes an average value of the signal. However, with the r.m.q.
average the influence of the higher magnitudes is stronger than with the r.m.s. A prescribed fixed integration time of
T = 3 s allows comparison of various measurement results and helps the tool operator to achieve reproducibility.
Experience shows that T = 3 s is a good compromise between the reaction time of the operator and the
requirement for shortest practicable integration time. In order to increase the confidence level of the results it is
advisable to take the average of this quantity over a series of single shocks (see 6.3).
4.13 Shock content quotient of W -weighted acceleration
h
Using the specifications in 4.11 and 4.12 the shock content quotient of a (t) is given by the quotient of the root-
hw
mean-quad and the root-mean-square values measured in the same time period T:
a
hw,RMQ,T
SC = (10)
hw
a
hw,RMS,T
This quantity describes the impulsiveness of the W frequency-weighted signal.
h
5 Measuring instrumentation
The root-mean-square value of the flat -weighted acceleration and W -weighted acceleration, defined in 4.3
h h
and 4.11, with integration time T = 3 s , can be determined with measuring instrumentation in accordance with
ENV 28041 as long as the frequency band of the flat response of the instrumentation is as defined in 4.2. For the
evaluation of all other parameters, the acceleration has to be measured with instrumentation which conforms to the
requirements of Annex A (for digital measuring instrumentation, see also Annex B).
NOTE The requirements of Annex A exceed those specified in ENV 28041.
In practice, it will be difficult to satisfy the requirements of all the annexes if mechanical filters are used.
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6 Measurement procedure
6.1 Attaching accelerometers
For the measurement of the flat -weighted quantities, in particular the peak values, the accelerometer shall be
h
rigidly fixed to give a flat frequency response in the frequency range 6,3 Hz to 1250 Hz. The guidelines for
mechanical mounting of accelerometers as given in ISO 5348 shall be followed.
To take into account the effects of elastic grips, the acceleration shall be measured at the interface between the
power tool and the operator’s hand by means of a suitable adaptor. In this case, special attention shall be paid to
measurement problems due to contact resonance.
For the measurement of W -weighted acceleration only, the guidance on accelerometer mounting given in
h
EN ISO 5349-2 should be followed.
If required, mechanical filters may be used when measuring the root-mean-square acceleration (flat -weighted or
h
W -weighted). However, when determining peak values, r.m.q. values or parameters derived from them, the use of
h
mechanical filters may produce errors and is not recommended.
NOTE 1 Some cements, such as those used for wire strain gauges, serve not just the purpose of fixation, but are also
designed to withstand high dynamic loads.
NOTE 2 In the case of plastic shell handles, the coupled mass of the accelerometer, including the adaptor, should be as
small and low in mass as possible. It is recommended that the mass is less than 12 g.
NOTE 3 The effect of accelerometer coupling on the measurement results can be determined by using laser vibrometers.
For general use, however, the application of laser vibrometers may be considered costly or impracticable.
6.2 Orientation of accelerometers
The accelerometers shall be oriented in the main excitation direction. In cases in which the main excitation direction
is not obvious it shall be determined by measurement in three orthogonal axes.
NOTE Inaccurate orientation yields incorrect results due to the transversal sensitivity of the accelerometer. Sensitivities
determined with cyclic signals are not valid for this application.
6.3 Working procedure
To distinguish the shock caused by the operating procedure from that caused by the power tool, it is necessary to
organise the procedure in a suitable way minimising the influence of the tool operator.
It is allowed to conduct the measurement with a series of n (e.g. n = 10) individual shocks or with single
sh sh
shocks. In cases where the repetition time can be varied, a repetition time of T = 3 s shall be used. When
rep
measuring with single shocks a measurement period of T = 3 s shall be used.
In cases where the measurement is conducted with a series of shocks, the root-mean-square and the root-mean-
quad parameters may be determined as the arithmetic average of the series.
7 Measurement report
The report shall include relevant information as prescribed by EN 1033, EN ISO 5349-1 or CEN ISO/TS 8662-11.
Furthermore, the following items shall be documented:
a) identification of the main excitation direction;
b) exact description of the coupling of the accelerometer;
c) mass of the accelerometers and the accessories (mechanical filters, adaptors, etc.);
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d) number of shocks during the measurement ( n );
sh
e) root-mean-square value of flat -weighted acceleration with T = 3 s ( a );
h
hF,RMS,3
f) root-mean-square value of W -weighted acceleration with T = 3 s ( a ).
h
hw,RMS,3
The following information is optional:
g) crest factor of flat -weighted acceleration with T = 3 s (CF );
h h
h) peak value of flat -weighted acceleration ( a );
h
hF,PV
i) shock content quotient of flat -weighted acceleration with T = 3 s (SC );
h h
j) shock content quotient of W -weighted acceleration with T = 3 s (SC );
h hw
k) maximum transient vibration value of flat -weighted acceleration and the time constant t ( a and t);
hthF,MTVV,
l) root-mean-quad value of flat -weighted acceleration with T = 3 s ( a );
h
hF,RMQ,3
m) root-mean-quad value of W -weighted acceleration with T = 3 s ( a ).
h
hw,RMQ,3
NOTE 1 The list of parameters above is not exhaustive. For research purposes, it may be necessary to add other
parameters.
NOTE 2 It is good practice to record the whole acceleration time history to allow for future re-analysis.
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Annex A
(normative)
Requirements and test methods for the measuring instrumentation
A.1 General
If the time history or the peak value of a signal is to be measured it is necessary to specify (and test) the phase
frequency response of the instrument in addition to the amplitude frequency response. Since this is missing from
the current standard for human vibration instrumentation (ENV 28041) such specifications and test procedures are
given in this annex.
The band-limiting filter shall be composed of a low-pass and a high-pass filter of second order with Butterworth
characteristic. The cut-off frequencies shall be 6,3 Hz and 1250 Hz for the high-pass and low-pass filters,
respectively.
To prescribe the requirements three frequency ranges are introduced:
Range 1: Interior frequency range from two third-octaves above the lower frequency band limit up to two third-
octaves below the upper frequency band limit (i.e. 10 Hz to 800 Hz), with the exception of
...