EN ISO 8041:2005

SLOVENSKI STANDARD
01-oktober-2005
1DGRPHãþD
SIST ENV 28041:2002
2G]LYDQMHþORYHNDQDYLEUDFLMH±0HULOQLLQVWUXPHQWDULM,62
Human response to vibration - Measuring instrumentation (ISO 8041:2005)
Schwingungseinwirkung auf den Menschen - Messeinrichtung (ISO 8041:2005)
Réponse des individus aux vibrations - Appareillage de mesure (ISO 8041:2005)
Ta slovenski standard je istoveten z: EN ISO 8041:2005
ICS:
13.160 Vpliv vibracij in udarcev na Vibration and shock with
ljudi respect to human beings
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN ISO 8041
NORME EUROPÉENNE
EUROPÄISCHE NORM
April 2005
ICS 13.160 Supersedes ENV 28041:1993
English version
Human response to vibration - Measuring instrumentation (ISO
8041:2005)
Réponse des individus aux vibrations - Appareillage de Schwingungseinwirkung auf den Menschen -
mesure (ISO 8041:2005) Messeinrichtung (ISO 8041:2005)
This European Standard was approved by CEN on 21 February 2005.

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 Central Secretariat 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 Central Secretariat has the same status as the official
versions.
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
© 2005 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 8041:2005: E
worldwide for CEN national Members.

Foreword
This document (EN ISO 8041:2005) has been prepared by Technical Committee ISO/TC 108
"Mechanical vibration and shock" in collaboration with Technical Committee CEN/TC 231
"Mechanical vibration and shock", the secretariat of which is held by DIN.

This European Standard shall be given the status of a national standard, either by publication of
an identical text or by endorsement, at the latest by October 2005, and conflicting national
standards shall be withdrawn at the latest by October 2005.

This document supersedes ENV 28041:1993.

According to the CEN/CENELEC Internal Regulations, the national standards organizations of
the following countries are bound to implement this European Standard: 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.

Endorsement notice
The text of ISO 8041:2005 has been approved by CEN as EN ISO 8041:2005 without any
modifications.
INTERNATIONAL ISO
STANDARD 8041
Second edition
2005-04-01
Human response to vibration —
Measuring instrumentation
Réponse des individus aux vibrations — Appareillage de mesure

Reference number
ISO 8041:2005(E)
©
ISO 2005
ISO 8041:2005(E)
PDF disclaimer
This PDF file may contain embedded typefaces. In accordance with Adobe's licensing policy, this file may be printed or viewed but
shall not be edited unless the typefaces which are embedded are licensed to and installed on the computer performing the editing. In
downloading this file, parties accept therein the responsibility of not infringing Adobe's licensing policy. The ISO Central Secretariat
accepts no liability in this area.
Adobe is a trademark of Adobe Systems Incorporated.
Details of the software products used to create this PDF file can be found in the General Info relative to the file; the PDF-creation
parameters were optimized for printing. Every care has been taken to ensure that the file is suitable for use by ISO member bodies. In
the unlikely event that a problem relating to it is found, please inform the Central Secretariat at the address given below.

©  ISO 2005
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or
ISO's member body in the country of the requester.
ISO copyright office
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail copyright@iso.org
Web www.iso.org
Published in Switzerland
ii © ISO 2005 – All rights reserved

ISO 8041:2005(E)
Contents Page
Foreword. v
1 Scope. 1
2 Normative references . 1
3 Terms, definitions and symbols . 2
3.1 Terms and definitions. 2
3.2 Symbols . 5
4 Reference environmental conditions. 7
5 Performance specifications . 7
5.1 General characteristics . 7
5.2 Display of signal magnitude . 9
5.3 Electrical output . 10
5.4 Vibration sensitivity. 10
5.5 Accuracy of indication at reference frequency under reference conditions . 10
5.6 Frequency weightings and frequency responses . 11
5.7 Amplitude linearity. 14
5.8 Instrument noise . 14
5.9 Signal-burst response . 14
5.10 Overload indication. 17
5.11 Under-range indication. 18
5.12 Time averaging. 18
5.13 Running r.m.s. acceleration. 18
5.14 Reset. 18
5.15 Timing facilities . 19
5.16 Electrical cross-talk . 19
5.17 Vibration transducer characteristics . 19
5.18 Power supply. 19
6 Mounting . 19
7 Environmental and electromagnetic criteria. 20
7.1 General. 20
7.2 Air temperature . 20
7.3 Surface temperature . 20
7.4 Electrostatic discharge. 20
7.5 Radio-frequency emissions and public-power-supply disturbances. 21
7.6 Immunity to a.c. power-frequency fields and radio-frequency fields. 21
7.7 Ingress of water and dust. 22
8 Provision for use with auxiliary devices. 22
9 Instrument marking. 22
10 Instrument documentation. 23
11 Testing and calibration. 23
12 Pattern evaluation . 24
12.1 Introduction . 24
12.2 Testing requirements. 25
12.3 Submission for testing . 25
12.4 Marking of the vibration meter and information in the instrument documentation. 25
12.5 Mandatory facilities and general requirements . 26
12.6 Initial instrument preparation . 26
ISO 8041:2005(E)
12.7 Indication at the reference frequency under reference conditions.26
12.8 Electrical cross-talk.27
12.9 Vibration transducer .27
12.10 Amplitude linearity and under-range indication .27
12.11 Frequency weightings and frequency responses.29
12.12 Instrument noise.32
12.13 Signal-burst response .32
12.14 Overload indication.32
12.15 Reset.33
12.16 Combined axis outputs.33
12.17 A.c. electrical output .33
12.18 Timing facilities .33
12.19 Power supply .34
12.20 Environmental, electrostatic and radio-frequency tests.34
12.21 Test report.38
13 Verification tests.38
13.1 Introduction.38
13.2 Testing requirements.38
13.3 Submission for a test.39
13.4 Marking of the vibration meter and information in the instrument documentation .39
13.5 Mandatory facilities and general requirements.39
13.6 Initial instrument preparation.39
13.7 Indication at the reference frequency under reference conditions.39
13.8 Electrical cross-talk.40
13.9 Amplitude linearity and under-range indication .40
13.10 Frequency weightings and frequency responses.41
13.11 Instrument noise.43
13.12 Signal-burst response .43
13.13 Overload indication.43
13.14 Reset.44
13.15 Combined axis outputs.44
13.16 Test report.44
14 In-situ checks.44
14.1 Introduction.44
14.2 Preliminary inspection.45
14.3 Vibration sensitivity (field calibration) .45
Annex A (normative) Specification for vibration field calibrator .46
Annex B (informative) Frequency weightings.49
Annex C (informative) Realization of frequency weighting filters .68
Annex D (informative) Running r.m.s. time averaging.72
Annex E (informative) Vibration transducer characteristics .74
Annex F (informative) Tests for mounting systems .76
Annex G (normative) Instrument documentation.79
Annex H (normative) Phase-response requirements for measurement of non-r.m.s. quantities .84
Bibliography.91

iv © ISO 2005 – All rights reserved

ISO 8041:2005(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 8041 was prepared by Technical Committee ISO/TC 108, Mechanical vibration and shock, Subcommittee
SC 3, Use and calibration of vibration and shock measuring instruments.
This second edition cancels and replaces the first edition (ISO 8041:1990), which has been technically
revised, and incorporates its Amendment, ISO 8041:1990/Amd.1:1999, and Technical Corrigendum
ISO 8041:1990/Cor.1:1993.
The reasons for the main changes introduced in this edition are as follows:
 to improve the specifications for human response to vibration measuring instrumentation;
 to incorporate into one document the specifications introduced by the 1999 amendment to ISO 8041:1990,
which themselves were required following the introduction of new frequency weightings in
ISO 2631-1:1997;
 to recognise changes in the frequency weighting specification introduced in ISO 5349-1:2001 that allows
frequencies outside the one-third octaves from 6,3 Hz to 1250 Hz to be excluded from the weighted
acceleration calculation (this is achieved by changing the frequencies at which the tolerance is extended
to −100 % to be the lower boundary of the 6,3 Hz one-third-octave bands and the upper boundary of the
1 250 Hz one-third-octave band);
 to introduce allowances for the uncertainties of testing the conformance of the human vibration measuring
instruments;
 to introduce a hierarchy of testing requirements (pattern evaluation, periodic verification and in-situ check)
with tests defined according to the needs of this hierarchy;
 to recognise the needs for the specification and testing of new parameters such as maximum transient
vibration value (MTVV) and vibration dose value (VDV);
 to recognise the need to test multi-axis instrumentation and to test combined results from these multi-axis
inputs;
 to introduce informative tests for mounting methods.
INTERNATIONAL STANDARD ISO 8041:2005(E)

Human response to vibration — Measuring instrumentation
1 Scope
This International Standard specifies the performance specifications and tolerance limits for instruments
designed to measure vibration values, for the purpose of assessing human response to vibration. It includes
requirements for pattern evaluation, periodic verification and in-situ checks, and the specification of vibration
calibrators for in-situ checks.
Vibration instruments specified in this International Standard can be single instruments, combinations of
instrumentation or computer-based acquisition and analysis systems.
Vibration instruments specified in this International Standard are intended to measure vibrations for one or
more applications, such as
 hand-transmitted vibration (see ISO 5349-1),
 whole-body vibration (see ISO 2631-1, ISO 2631-2, ISO 2631-4), and
 low-frequency whole-body vibration in the frequency range from 0,1 Hz to 0,5 Hz (see ISO 2631-1).
Vibration instruments can be designed for measurement according to one or more of the frequency weightings
defined within each of these applications.
Three levels of performance testing are defined in this International Standard:
a) pattern evaluation, i.e. a full test of the instrument against the specifications defined in this International
Standard;
b) periodic verification, i.e. an intermediate set of tests designed to ensure that an instrument remains within
the required performance specification, and
c) in-situ checks, i.e. a minimum level of testing required to indicate that an instrument is likely to be
functioning within the required performance specification.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO 2041, Vibration and shock — Vocabulary
ISO 2631-1, Mechanical vibration and shock — Evaluation of human exposure to whole-body vibration —
Part 1: General requirements
ISO 2631-2, Mechanical vibration and shock — Evaluation of human exposure to whole-body vibration —
Part 2: Vibration in buildings (1 Hz to 80 Hz)
ISO 2631-4, Mechanical vibration and shock — Evaluation of human exposure to whole-body vibration —
Part 4: Guidelines for the evaluation of the effects of vibration and rotational motion on passenger and crew
comfort in fixed-guideway transport systems
ISO 5347 (all parts), Methods for the calibration of vibration and shock pick-ups
ISO 8041:2005(E)
ISO 5348, Mechanical vibration and shock — Mechanical mounting of accelerometers
ISO 5349-1:2001, Mechanical vibration — Measurement and evaluation of human exposure to
hand-transmitted vibration — Part 1: General requirements
ISO 16063 (all parts), Methods for the calibration of vibration and shock transducers
IEC 61000-4-2:2001, Electromagnetic compatibility (EMC) — Part 4-2: Testing and measurement
techniques — Electrostatic discharge immunity test
IEC 61000-4-3:2002, Electromagnetic compatibility (EMC) — Part 4-3: Testing and measurement
techniques —Radiated, radio-frequency, electromagnetic field immunity test
IEC 61000-4-6, Electromagnetic compatibility (EMC) — Part 4-6: Testing and measurement techniques —
Immunity to conducted disturbances, induced by radio-frequency fields
IEC 61000-6-2:1999, Electromagnetic compatibility (EMC) — Part 6-2: Generic standards — Immunity for
industrial environments
CISPR 22:2003, Information technology equipment — Radio disturbance characteristics — Limits and
methods of measurement
GUM, Guide to the expression of uncertainty in measurement. BIPM, IEC, IFCC, ISO, IUPAC, IUPAP, OIML,
3 Terms, definitions and symbols
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 2041, together with the following,
apply.
3.1.1
vibration acceleration
component of acceleration, where the axis of measurement is specified by application standards
3.1.2
band-limiting frequency weighting
component of a frequency weighting defined by the high and low pass band-limiting filters
3.1.3
band-limited frequency range
frequency range defined by the band-limited component of a frequency weighting
3.1.4
nominal frequency range
frequency range of interest, as defined in the relevant measurement standard
3.1.5 Frequency-weighted values
3.1.5.1
time-averaged weighted acceleration value
frequency-weighted r.m.s. vibration acceleration value in a specified axis, a , in metres per second squared or
w
radians per second squared, as defined by the expression:
T


aa= ξξd (1)
()
ww
∫

T
0
2 © ISO 2005 – All rights reserved

ISO 8041:2005(E)
where
a (ξ ) is the translational or rotational, weighted vibration acceleration in a specified axis as a function
w
of the instantaneous time, ξ, in metres per second squared (m/s ) or radians per second
squared (rad/s ), respectively;
T is the duration of the measurement
3.1.5.2
time-averaged weighted acceleration level
frequency-weighted r.m.s. vibration acceleration level expressed in decibels, as defined by
a
w
L = 20 lg dB (2)
w
a
where
a is defined in 3.1.5.1;
w
−6 2
a is the reference acceleration (defined as 10 m/s in ISO 1683)
3.1.5.3
running r.m.s. acceleration value
frequency-weighted running r.m.s. vibration acceleration, in metres per second squared, defined by the
expression
t 2


at = a ξξd (3)
() ()
w,θ w
∫
θ
t−θ

where
a (ξ ) is the frequency-weighted instantaneous vibration acceleration at time ξ , in metres per second
w
squared;
θ is the integration time of the measurement;
t is the instantaneous time
NOTE Exponential averaging may be used for the running r.m.s. method, as an approximation of the linear averaging.
The exponential averaging is defined as follows:
t

1 ξ − t

at = aξξexp d (4)
() ()
w,τ w 
∫

ττ

−∞

where τ is the time constant.
3.1.5.4
maximum transient vibration value
MTVV
maximum value of the running r.m.s. vibration acceleration value when the integration time is equal to 1 s
3.1.5.5
motion sickness dose value
MSDV
1,5
integral of the squared weighted instantaneous vibration acceleration a (t) in m/s as defined by the
w
expression:
ISO 8041:2005(E)
Φ


MSDV = a ξξd (5)
()
w
∫

0
where Φ is the total period during which motion could occur
NOTE 1 The motion sickness dose value may be obtained from the frequency weighted r.m.s. vibration acceleration
through multiplication by Φ .
NOTE 2 For measurement instrumentation, the exposure period Φ is likely to be assumed to be equal to the
measurement period, T, unless otherwise indicated.
3.1.5.6
vibration dose value
VDV
1,75
integral of the fourth power of the weighted instantaneous vibration acceleration a (t) in m/s as defined by
w
the expression
Φ


VDV = a ()ξξd (6)
w
∫

0
where Φ is the total (daily) period for which exposure occurs
NOTE 1 The vibration dose value is more sensitive to peaks than is the r.m.s. value.
NOTE 2 For measurement instrumentation, the exposure period Φ is likely to be assumed to be equal to the
measurement period, T, unless otherwise indicated.
3.1.5.7
vibration total value
combined vibration from three axes of translational vibration, as defined by the expression
22 2
a=+kakak+ a (7)
wwvxx ywy zwz
where
a , a and a are the vibration values in the three orthogonal axes x, y and z;
wx wy wz
k , k and k are multiplying constants whose values depend on the measurement application
x y z
3.1.5.8
peak vibration value
maximum modulus of the instantaneous (positive and negative) peak values of the frequency-weighted
acceleration
3.1.5.9
crest factor
parameter for a measurement period, given by the peak vibration value divided by the r.m.s. acceleration
value, with both values having the same frequency weighting
3.1.6
linear operating range
on each measurement range, the range between lower and upper boundaries over which the linearity errors
are within the applicable tolerance limits specified in this International Standard
4 © ISO 2005 – All rights reserved

ISO 8041:2005(E)
3.1.7
overload
condition that occurs when the upper boundary of the linear operating range is exceeded
3.1.8
under-range
condition that occurs when the vibration value is below the lower boundary of the linear operating range
3.1.9
reference measurement range
level range specified for testing the characteristics of the vibration instrumentation
NOTE This range is that used for measuring the reference vibration.
3.1.10
reference vibration signal
sinusoidal vibration signal, the magnitude and frequency of which is specified in this International Standard for
testing the electromechanical performance of a human-vibration meter
NOTE Different reference vibration signals are specified according to the application of the instrumentation.
3.1.11
calibration check frequency
frequency specified for providing a check of the vibration sensitivity of the instrument
3.1.12
tone burst
one or more complete cycles of a sinusoidal signal that start and end at a zero crossing of the waveform
3.1.13
signal burst
one or more complete cycles of a periodic signal (such as saw-tooth) that start and end at a zero crossing of
the waveform
3.1.14
vibration measuring instrumentation
combination of a vibration transducer, signal processor and display, being any single instrument, or a
collection of instruments, which is capable of measuring parameters relating to human response to vibration
NOTE See Figure 1.
3.1.15
instrument documentation
instruction manual, operating procedure, or other documentation provided for the use of users of the vibration
measurement instrument
3.2 Symbols
For the purposes of this document, the following symbols and abbreviated terms are used:
a time-averaged frequency-weighted single-axis vibration acceleration
w
a (t), a (ξ ) instantaneous frequency-weighted translational or rotational single-axis acceleration at time t,
w w
or timeξ
f frequency
H overall frequency weighting function
k multiplying constants applied to the whole-body frequency-weighted acceleration value for axis i
i
n one-third-octave band number
ISO 8041:2005(E)
t or ξ instantaneous time
T measurement duration
s variable of the Laplace transform
W frequency weighting x
x
Φ exposure duration
∆ϕ phase error
τ exponential averaging time constant
θ linear averaging time
MTVV maximum transient vibration value
MSDV motion sickness dose value
VDV vibration dose value
Key
1 transducer 8 frequency weighting (including band-limiting)
2 mounting system 9 band-limited output
3 vibrating surface 10 frequency-weighted output
4 cable 11 time weighting
5 electrical input 12 additional processing
6 signal conditioning 13 display

7 band limiting
a)  Time-domain signal processing
Figure 1 — Overview of the basic functional path output of a vibration measurement instrument or
measurement system
6 © ISO 2005 – All rights reserved

ISO 8041:2005(E)
Key
1 transducer 8 band limiting (calculation)
2 mounting system 9 frequency weighting — including band limiting
(calculation)
3 vibrating surface
10 band-limited output
4 cable
11 frequency-weighted output
5 electrical input
12 accumulation of frequency bands
6 signal conditioning
13 display
7 frequency analysis
time weighting
time averaging
b)  Frequency-domain signal processing (not applicable to VDV processing)
Figure 1 (continued)
4 Reference environmental conditions
Reference environmental conditions for specifying the performance of a vibration meter are
 air temperature: 23 °C;
 relative humidity: 50 %.
5 Performance specifications
5.1 General characteristics
The performance specifications of this clause apply under the reference environmental conditions.
As a minimum, human-vibration measuring instrumentation shall provide a means of displaying
 time-averaged weighted vibration acceleration value over the measurement duration,
ISO 8041:2005(E)
 band-limited time-averaged vibration acceleration value over the measurement duration, and
 measurement duration.
The human-vibration measuring instrument shall also provide a means of indicating whether an overload
occurred at any time within the measurement duration.
The human-vibration measuring instrument shall provide a method for setting and adjusting the vibration
sensitivity.
Human-vibration measuring instruments may contain any or all of the design features for which performance
specifications are given in this International Standard. An instrument shall conform to the applicable
performance specifications for those design features that are provided.
If the instrument has more than one measurement range, the instrument documentation shall describe the
measurement ranges that are included and the operation of the measurement range control. The instrument
documentation shall also identify which is the reference measurement range.
The reference vibration signal frequencies and values are given in Table 1.
If the instrument is capable of measuring the maximum (e.g. MTVV) and peak vibration values, a “hold"
function shall be provided. The instrument documentation shall describe the operation of the hold feature and
the method for clearing a display that is held.
Many of the specifications and tests in this International Standard require the application of electrical signals
substituting for the signal from the vibration transducer. The instrument documentation shall specify a means
for substituting an electrical signal, equivalent to the signal from the vibration transducer, for performing
electrical tests on the complete instrument without the vibration transducer. If appropriate, the instrument
documentation may describe alternative methods to test the specified operations of the human vibration meter.
NOTE The manufacturer of the human-vibration meter may provide an input test point, or a dummy vibration
transducer of specified electrical impedance, or an equivalent input adapter (electrical or non-electrical) to perform
electrical tests on the instrument.
The instrument documentation shall specify the maximum peak vibration at the vibration transducer and the
maximum peak-to-peak signal (e.g. charge or voltage) that can be applied at the electrical input facility. The
maximum vibration value and the maximum peak-to-peak voltage shall not cause damage to the instrument.
Table 1 — Reference vibration values and frequencies
Weighting Weighted
Table in
Nominal
Frequency factor at acceleration
annex
Application frequency Reference
weighting
reference at reference
range
(informative)
frequency frequency and
r.m.s.
r.m.s.
acceleration
Frequency acceleration
value
value
Hz m/s
m/s
500 rad/s
W
Hand-transmitted B.6 8 to 1 000 10 0,202 0 2,020
h
(79,58 Hz)
W
B.1 0,812 6 0,812 6
b
W B.2 0,514 5 0,514 5
c
W
B.3 0,126 1 0,126 1
d
0,5 to 80
100 rad/s
Whole-body W 1
B.4 0,062 87 0,062 87
e
(15,915 Hz)
W B.7 1,019 1,019
j
W
B.8 0,771 8 0,771 8
k
W
B.9 1 to 80 0,336 2 0,336 2
m
2,5 rad/s
Low-frequency
W
B.5 0,1 to 0,5 0,1 0,388 8 0,038 88
f
whole-body
(0,397 9 Hz)
8 © ISO 2005 – All rights reserved

ISO 8041:2005(E)
The tolerance limits given in this International Standard include the associated expanded uncertainties of
measurement, calculated for a coverage factor of 2, corresponding to a level of confidence of approximately
95 %, in accordance with guidance given in the GUM.
5.2 Display of signal magnitude
5.2.1 General
For instruments that can display more than one measurement quantity, a means shall be provided to ascertain
clearly the measurement quantity that is being displayed, preferably indicated by standard abbreviations or
letter symbols.
The quantities that can be displayed by the human-vibration meter shall be described in the instrument
documentation, along with a description of the corresponding indications on each display device.
The instrument shall display the frequency-weighted acceleration values. Optionally, it may also display the
frequency-weighted acceleration value multiplied by a factor k, as defined in ISO 2631-1. Where the
multiplying factors are used, this shall be clearly indicated on the instrument and the instrument shall be
capable of displaying the multiplying factors.
Where a combined axis output is displayed [e.g. vibration total value, Equation (7)], the instrument shall be
capable of displaying the values of the multiplying factors used.
When results of a measurement are provided at a digital output, the instrument documentation shall describe
the method for transferring or downloading the digital data to an external data-storage or display device. The
instrument documentation shall identify the computer software as well as the hardware for the interface.
Internationally standardized interface bus compatibility is recommended.
Each alternative device for displaying the signal value, stated in the instrument documentation as conforming
to the specifications of this International Standard, is considered an integral part of the instrument. Each such
alternative device shall be included as part of the components required for conformance to the performance
specifications in this clause and the applicable environmental specifications of Clause 7. Examples of
alternative display devices include level recorders or computers with monitor screens.
For an instrument that uses a display device with a range less than the linear operating range specified in 5.7,
the instrument documentation shall describe a means to test the linearity beyond the limits of the indicator
range.
5.2.2 Resolution and refresh rate
The display device(s) specified in the instrument documentation shall permit measurements with a resolution
of 1 % of the indicated value, or better.
If an instrument only has an analog, or simulated analog, display device that provides a continuous indication,
the display shall be a logarithmic display of the vibration value. The range of the analog display device shall
include a display of at least 2 decades, with each decade being at least 10 mm wide. Where the display range
does not encompass the whole of the linearity range of the instrument, then the display range shall be
switchable to allow for the whole of the linearity range to be viewed.
If a digital indicator is provided, and the measurement quantity displayed is a vibration parameter, the display
shall be updated at regular time intervals. The time interval between updates shall be appropriate to the
measurement being displayed. The extent of the range of a digital display shall be at least sufficient to cover
the linear operating range.
For instruments with digital display devices updated at periodic intervals, the indication at each display update
shall be the value of the user-selected quantity at the time of the display update. Other modes of indication at
the time of the display update may be identified in the instrument documentation and, if so, the operation of
ISO 8041:2005(E)
such modes shall be explained in the instrument documentation. The instrument documentation shall state
which modes conform to the specifications of this International Standard and which do not conform.
5.2.3 Stabilization, measurement start and display times
Within the prevailing environmental conditions, the time interval required for stabilizing and being ready to use
shall be no greater than 2 min from switching on the instrument.
The display shall indicate when the instrument is ready for use following switch-on, range change or changes
to filter selection.
The time between a user initiating a measurement and the start of that measurement shall be no greater than
0,5 s.
NOTE This may require an initialization procedure, particularly for low-frequency whole-body vibration: an operating
phase prior to measurement initiation that ensures that the instrument has settled following the end of a previous
measurement.
Prior to a measurement result being available, the instrument display shall clearly indicate whether a
measurement is in progress, or whether an initialization stage is underway.
5.3 Electrical output
If an a.c. electrical output is provided, the instrument documentation shall state the characteristics of the
output signals. The characteristics shall include
 the range of peak-to-peak voltages, which shall be not less than 1 V peak-to-peak,
 the internal electrical impedance at the output,
 the minimum load impedance, and
 the frequency weightings applied to the output signals.
Connection of passive impedance without stored electrical energy, including a short circuit, to the electrical
output shall not affect any measurement in progress by more than 2 %.
5.4 Vibration sensitivity
The instrument documentation shall specify at least one model of vibration field calibrator as a means to
check and maintain the mechanic
...