Acoustics - Rating of sound insulation in buildings and of building elements - Part 1: Airborne sound insulation (ISO 717-1:2020)

This document
a) defines single-number quantities for airborne sound insulation in buildings and of building
elements such as walls, floors, doors, and windows,
b) takes into consideration the different sound level spectra of various noise sources such as noise
sources inside a building and traffic outside a building, and
c) gives rules for determining these quantities from the results of measurements carried out in onethird-
octave or octave bands for example in accordance with ISO 10140-2 and ISO 16283-1.
The single-number quantities in accordance with this document are intended for rating airborne
sound insulation and for simplifying the formulation of acoustical requirements in building codes. An
additional single-number evaluation in steps of 0,1 dB is indicated for the expression of uncertainty
(except for spectrum adaptation terms). The required numerical values of the single-number quantities
are specified according to varying needs. The single-number quantities are based on results of
measurements in one-third-octave bands or octave bands.
For laboratory measurements made in accordance with ISO 10140-2, single-number quantities are
calculated using one-third-octave bands only.
The rating of results of measurements carried out over an enlarged frequency range is dealt with in
Annex B.

Akustik - Bewertung der Schalldämmung in Gebäuden und von Bauteilen - Teil 1: Luftschalldämmung (ISO 717-1:2020)

Dieses Dokument
a) legt Einzahlangaben für die Luftschalldämmung in Gebäuden und von Bauteilen wie Wänden, Decken, Türen und Fenstern fest,
b) berücksichtigt die verschiedenen Schallpegelspektren verschiedener Geräuschquellen, wie Geräusche in einem Gebäude und Verkehrsgeräusche außerhalb eines Gebäudes, und
c) enthält Regeln für die Ermittlung dieser Einzahlangaben aus den Ergebnissen von Messungen in Terz- oder Oktavbändern, z. B. nach ISO 10140 2 und ISO 16283 1.
Die Einzahlangaben nach diesem Dokument sind für die Bewertung der Luftschalldämmung und für die Vereinfachung der Formulierung von akustischen Anforderungen in Bauvorschriften vorgesehen. Zum Zwecke der Angabe der Unsicherheit ist die Ermittlung einer zusätzlichen Einzahlangabe in 0,1 dB-Schritten enthalten (ausgenommen sind die Spektrum-Anpassungswerte). Die erforderlichen numerischen Werte dieser Einzahlangaben werden für verschiedene Bedürfnisse festgelegt. Grundlage für die Einzahlangaben sind Ergebnisse aus Messungen in Terzbändern oder in Oktavbändern.
Bezüglich der Messungen in Prüfständen nach ISO 10140 2 werden Einzahlangaben nur auf der Grundlage von Terzbändern berechnet.
Die Bewertung der Ergebnisse von Messungen über einen erweiterten Frequenzbereich wird im Anhang B behandelt.

Acoustique - Évaluation de l'isolement acoustique des immeubles et des éléments de construction - Partie 1: Isolement aux bruits aériens (ISO 717-1:2020)

Akustika - Vrednotenje zvočne izolirnosti v stavbah in zvočne izolirnosti gradbenih elementov - 1. del: Izolirnost pred zvokom v zraku (ISO 717-1:2020)

General Information

Status
Published
Current Stage
6060 - Definitive text made available (DAV) - Publishing
Due Date
16-Dec-2020
Completion Date
16-Dec-2020

RELATIONS

Buy Standard

Standard
EN ISO 717-1:2021
English language
34 pages
sale 10% off
Preview
sale 10% off
Preview

e-Library read for
1 day

Standards Content (sample)

SLOVENSKI STANDARD
SIST EN ISO 717-1:2021
01-marec-2021
Nadomešča:
SIST EN ISO 717-1:2013

Akustika - Vrednotenje zvočne izolirnosti v stavbah in zvočne izolirnosti gradbenih

elementov - 1. del: Izolirnost pred zvokom v zraku (ISO 717-1:2020)

Acoustics - Rating of sound insulation in buildings and of building elements - Part 1:

Airborne sound insulation (ISO 717-1:2020)
Akustik - Bewertung der Schalldämmung in Gebäuden und von Bauteilen - Teil 1:
Luftschalldämmung (ISO 717-1:2020)

Acoustique - Évaluation de l'isolement acoustique des immeubles et des éléments de

construction - Partie 1: Isolement aux bruits aériens (ISO 717-1:2020)
Ta slovenski standard je istoveten z: EN ISO 717-1:2020
ICS:
91.120.20 Akustika v stavbah. Zvočna Acoustics in building. Sound
izolacija insulation
SIST EN ISO 717-1:2021 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
SIST EN ISO 717-1:2021
---------------------- Page: 2 ----------------------
SIST EN ISO 717-1:2021
EN ISO 717-1
EUROPEAN STANDARD
NORME EUROPÉENNE
December 2020
EUROPÄISCHE NORM
ICS 91.120.20 Supersedes EN ISO 717-1:2013
English Version
Acoustics - Rating of sound insulation in buildings and of
building elements - Part 1: Airborne sound insulation (ISO
717-1:2020)

Acoustique - Évaluation de l'isolement acoustique des Akustik - Bewertung der Schalldämmung in Gebäuden

immeubles et des éléments de construction - Partie 1: und von Bauteilen - Teil 1: Luftschalldämmung (ISO

Isolement aux bruits aériens (ISO 717-1:2020) 717-1:2020)
This European Standard was approved by CEN on 12 December 2020.

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-CENELEC 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-CENELEC Management

Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,

Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,

Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and

United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels

© 2020 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 717-1:2020 E

worldwide for CEN national Members.
---------------------- Page: 3 ----------------------
SIST EN ISO 717-1:2021
EN ISO 717-1:2020 (E)
Contents Page

European foreword ....................................................................................................................................................... 3

---------------------- Page: 4 ----------------------
SIST EN ISO 717-1:2021
EN ISO 717-1:2020 (E)
European foreword

This document (EN ISO 717-1:2020) has been prepared by Technical Committee ISO/TC 43 "Acoustics"

in collaboration with Technical Committee CEN/TC 126 “Acoustic properties of building elements and

of buildings” the secretariat of which is held by AFNOR.

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 June 2021, and conflicting national standards shall be

withdrawn at the latest by June 2021.

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. CEN shall not be held responsible for identifying any or all such patent rights.

This document supersedes EN ISO 717-1:2013.

According to the CEN-CENELEC Internal Regulations, the national standards organizations of the

following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,

Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,

Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of

North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the

United Kingdom.
Endorsement notice

The text of ISO 717-1:2020 has been approved by CEN as EN ISO 717-1:2020 without any modification.

---------------------- Page: 5 ----------------------
SIST EN ISO 717-1:2021
---------------------- Page: 6 ----------------------
SIST EN ISO 717-1:2021
INTERNATIONAL ISO
STANDARD 717-1
Fourth edition
2020-12
Acoustics — Rating of sound
insulation in buildings and of building
elements —
Part 1:
Airborne sound insulation
Acoustique — Évaluation de l'isolement acoustique des immeubles et
des éléments de construction —
Partie 1: Isolement aux bruits aériens
Reference number
ISO 717-1:2020(E)
ISO 2020
---------------------- Page: 7 ----------------------
SIST EN ISO 717-1:2021
ISO 717-1:2020(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2020

All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may

be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting

on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address

below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO 2020 – All rights reserved
---------------------- Page: 8 ----------------------
SIST EN ISO 717-1:2021
ISO 717-1:2020(E)
Contents Page

Foreword ........................................................................................................................................................................................................................................iv

Introduction ..................................................................................................................................................................................................................................v

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ...................................................................................................................................................................................... 1

3 Terms and definitions ..................................................................................................................................................................................... 2

4 Procedure for evaluating single-number quantities....................................................................................................... 2

4.1 General ........................................................................................................................................................................................................... 2

4.2 Reference values .................................................................................................................................................................................... 4

4.3 Sound spectra ........................................................................................................................................................................................... 4

4.4 Method of comparison ..................................................................................................................................................................... 4

4.5 Calculation of spectrum adaptation terms ..................................................................................................................... 8

5 Statement of results .......................................................................................................................................................................................... 9

5.1 General ........................................................................................................................................................................................................... 9

5.2 Statement of performance of building elements ....................................................................................................... 9

5.3 Statement of requirements and of performance of buildings .....................................................................10

Annex A (informative) Use of spectrum adaptation terms .........................................................................................................11

Annex B (informative) Terms and spectra for an enlarged frequency range ..........................................................13

Annex C (informative) Examples of the calculation of single-number quantities and

spectrum adaptation terms....................................................................................................................................................................16

Annex D (normative) Single-number rating for improvement of sound reduction index by

linings............................................................................................................................................................................................................................19

Annex E (normative) Standard basic elements for measuring the improvement of airborne

sound insulation by linings ....................................................................................................................................................................21

Bibliography .............................................................................................................................................................................................................................26

© ISO 2020 – All rights reserved iii
---------------------- Page: 9 ----------------------
SIST EN ISO 717-1:2021
ISO 717-1:2020(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.

The procedures used to develop this document and those intended for its further maintenance are

described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the

different types of ISO documents should be noted. This document was drafted in accordance with the

editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).

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. Details of

any patent rights identified during the development of the document will be in the Introduction and/or

on the ISO list of patent declarations received (see www .iso .org/ patents).

Any trade name used in this document is information given for the convenience of users and does not

constitute an endorsement.

For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and

expressions related to conformity assessment, as well as information about ISO's adherence to the

World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www .iso .org/

iso/ foreword .html.

This document was prepared by Technical Committee ISO/TC 43, Acoustics, Subcommittee SC 2,

Building acoustics, in collaboration with the European Committee for Standardization (CEN) Technical

Committee CEN/TC 126, Acoustic properties of building elements and of buildings, in accordance with the

Agreement on technical cooperation between ISO and CEN (Vienna Agreement).

This fourth edition cancels and replaces the third edition (ISO 717-1:2013), which has been technically

revised.
The main changes compared to the previous edition are as follows:
— ISO 10140-1:2016, G.6 relocated into this document;
— ISO 10140-5:2010, Annex B relocated into this document;
— references updated.
A list of all parts in the ISO 717 series can be found on the ISO website.

Any feedback or questions on this document should be directed to the user’s national standards body. A

complete listing of these bodies can be found at www .iso .org/ members .html.
iv © ISO 2020 – All rights reserved
---------------------- Page: 10 ----------------------
SIST EN ISO 717-1:2021
ISO 717-1:2020(E)
Introduction

Methods of measurement of airborne sound insulation of building elements and in buildings have been

standardized e.g. in ISO 10140-2 and ISO 16283-1. The purpose of this document is to standardize a

method whereby the frequency-dependent values of airborne sound insulation can be converted into a

single number characterizing the acoustical performance.

References to standards which provide data for single-number evaluation are meant to be examples

and therefore are not complete.
© ISO 2020 – All rights reserved v
---------------------- Page: 11 ----------------------
SIST EN ISO 717-1:2021
---------------------- Page: 12 ----------------------
SIST EN ISO 717-1:2021
INTERNATIONAL STANDARD ISO 717-1:2020(E)
Acoustics — Rating of sound insulation in buildings and of
building elements —
Part 1:
Airborne sound insulation
1 Scope
This document

a) defines single-number quantities for airborne sound insulation in buildings and of building

elements such as walls, floors, doors, and windows,

b) takes into consideration the different sound level spectra of various noise sources such as noise

sources inside a building and traffic outside a building, and

c) gives rules for determining these quantities from the results of measurements carried out in one-

third-octave or octave bands for example in accordance with ISO 10140-2 and ISO 16283-1.

The single-number quantities in accordance with this document are intended for rating airborne

sound insulation and for simplifying the formulation of acoustical requirements in building codes. An

additional single-number evaluation in steps of 0,1 dB is indicated for the expression of uncertainty

(except for spectrum adaptation terms). The required numerical values of the single-number quantities

are specified according to varying needs. The single-number quantities are based on results of

measurements in one-third-octave bands or octave bands.

For laboratory measurements made in accordance with ISO 10140-2, single-number quantities are

calculated using one-third-octave bands only.

The rating of results of measurements carried out over an enlarged frequency range is dealt with in

Annex B.
2 Normative references

The following documents are referred to in the text in such a way that some or all of their content

constitutes requirements 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 10140-1:2016, Acoustics — Laboratory measurement of sound insulation of building elements —

Part 1: Application rules for specific products

ISO 10140-2:2010, Acoustics — Laboratory measurement of sound insulation of building elements —

Part 2: Measurement of airborne sound insulation

ISO 10140-5:2010, Acoustics — Laboratory measurement of sound insulation of building elements —

Part 5: Requirements for test facilities and equipment

ISO 10848-2:2017, Acoustics — Laboratory and field measurement of flanking transmission for airborne,

impact and building service equipment sound between adjoining rooms — Part 2: Application to Type B

elements when the junction has a small influence

ISO 15186-1:2000, Acoustics — Measurement of sound insulation in buildings and of building elements

using sound intensity — Part 1: Laboratory measurements
© ISO 2020 – All rights reserved 1
---------------------- Page: 13 ----------------------
SIST EN ISO 717-1:2021
ISO 717-1:2020(E)

ISO 16283-1:2014, Acoustics — Field measurement of sound insulation in buildings and of building

elements — Part 1: Airborne sound insulation

ISO 16283-1:2014/Amd 1:2017, Acoustics — Field measurement of sound insulation in buildings and of

building elements — Part 1: Airborne sound insulation — Amendment 1

ISO 16283-3:2016, Acoustics — Field measurement of sound insulation in buildings and of building

elements — Part 3: Façade sound insulation
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1
single-number quantity

value, in decibels, of the reference curve at 500 Hz after shifting

it in accordance with the method specified in this document

Note 1 to entry: Terms and symbols for the single-number quantity used depend on the type of measurement.

Examples are listed in Table 1 for airborne sound insulation properties of building elements and in Table 2 for

airborne sound insulation in buildings. In general, new single-number quantities are derived in a similar way.

3.2
spectrum adaptation term

value, in decibels, to be added to the single-number rating (e.g. R ) to take account of the characteristics

of particular sound spectra

Note 1 to entry: Two sound spectra are defined (in one-third-octave bands and in octave bands) in this document.

Note 2 to entry: Annex A gives information on the purpose of introducing these two spectrum adaptation terms

C and C .
4 Procedure for evaluating single-number quantities
4.1 General

The values obtained in accordance with e.g. ISO 10140-2 and ISO 16283-1 are compared with reference

values (see 4.2) at the frequencies of measurement within the range 100 Hz to 3 150 Hz for one-third-

octave bands and 125 Hz to 2 000 Hz for octave bands.
The comparison shall be carried out as specified in 4.4.

Furthermore, two spectrum adaptation terms shall be calculated (see 4.5) based on two typical spectra

within the frequency range as quoted above. These two terms may optionally be supplemented by

additional spectrum adaptation terms covering (if need be and if measured data are available) a wider

frequency range between 50 Hz and 5 000 Hz.
2 © ISO 2020 – All rights reserved
---------------------- Page: 14 ----------------------
SIST EN ISO 717-1:2021
ISO 717-1:2020(E)

Table 1 — Single-number quantities of airborne sound insulation properties of building

elements
Derived from one-third-octave band values
Defined in
Single-number quantity Term and symbol

Weighted sound reduction index, R Sound reduction index, R ISO 10140-2:2010 Formula (2)

Weighted normalized flanking level Normalized flanking level
ISO 10848-2:2017 3.1
difference, D difference, D
n,f,w n,f
Weighted element-normalized level Element-normalized level
ISO 10140-2:2010 Formula (5)
difference, D difference, D
n,e,w n,e
Weighted joint sound insulation Joint sound insulation ISO 10140-1:2016,
Formula (J.1).
index, R index, R Annex J
s,w s
Weighted intensity sound insulation Intensity sound insulation
ISO 15186-1:2000 Formula (7)
index, R index, R
I,W I
Table 2 — Single-number quantities of airborne sound insulation in buildings
Derived from one third octave band values or octave band values
Defined in
Single-number quantity Term and symbol
Weighted apparent sound reduction Apparent sound reduction ISO 16283-1:2014/
Formula (4)
index, R′ index, R′ Amd 1:2017
Weighted apparent sound reduction Apparent sound reduction
ISO 16283-3: 2016 3.12
index, R′ index, R′
45°,w 45°
Weighted apparent sound reduction Apparent sound reduction
ISO 16283-3: 2016 3.13
index, R′ index, R′
tr,s,w tr,s
Weighted normalized level difference, Normalized
ISO 10140-2:2010 Formula (5)
D level difference, D
n,w n
Weighted standardized level difference, Standardized
ISO 16283-1:2014 Formula (2)
D level difference, D
nT,w nT
Weighted standardized level difference, Standardized level differ-
ISO 16283-3:2016 3.15
D or D ence, D or D
ls,2m,nT,w tr,2m,nT,w ls,2m,nT tr,2m,nT
Weighted normalized level difference, Normalized level
ISO 16283-3:2016 3.16
D or D difference, D or D
ls,2m,n,w tr,2m,n,w ls,2m,n tr,2m,n
© ISO 2020 – All rights reserved 3
---------------------- Page: 15 ----------------------
SIST EN ISO 717-1:2021
ISO 717-1:2020(E)
4.2 Reference values

The set of reference values used for comparison with measurement results shall be as given in Table 3.

The reference curves are shown in Figure 1 and Figure 2.
Table 3 — Reference values for airborne sound
Frequency Reference values
Hz One-third-octave bands Octave bands
100 33
125 36 36
160 39
200 42
250 45 45
315 48
400 51
500 52 52
630 53
800 54
1 000 55 55
1 250 56
1 600 56
2 000 56 56
2 500 56
3 150 56
4.3 Sound spectra

The set of sound spectra in one-third-octave bands and octave bands to calculate the spectrum

adaptation terms shall be as given in Table 4 and shown in Figure 3 and Figure 4. The spectra are

A-weighted and the overall spectrum level is normalized to 0 dB.
4.4 Method of comparison

To evaluate the results of a sound insulation measurement in one-third-octave bands (or octave bands),

the measurement data shall be given to one decimal place . Shift the relevant reference curve in

increments of 1 dB (0,1 dB for the expression of uncertainty) towards the measured curve until the sum

of unfavourable deviations is as large as possible, but not more than 32,0 dB (measurement in 16 one-

third-octave bands) or 10,0 dB (measurement in 5 octave bands).

1) ISO 10140-2 and ISO 16283-1 state that the results shall be reported “to one decimal place”. However, if the

octave or one-third-octave values have been reported with more than one decimal digit, the values should be reduced

to one decimal place before use in the calculation of the single number rating. This is done by taking the value in

tenths of a decibel closest to the reported values: XX,XYZ ZZ ... is rounded to XX,X if Y is less than 5 and to XX,X + 0,1

if Y is equal to or greater than 5. Software developers should ensure that this reduction applies to the true input

values and not only to the displayed precision (as shown on the screen or printed on paper). Generally this can be

implemented by the following sequence of instructions: multiply the (positive) number XX,XYZ ZZ ... by 10 and add

[1]

0,5, take the integer part and then divide the result by 10. For further details see ISO 80000-1 .

4 © ISO 2020 – All rights reserved
---------------------- Page: 16 ----------------------
SIST EN ISO 717-1:2021
ISO 717-1:2020(E)
Key
f frequency, in Hz
L reference value, in dB
Figure 1 — Curve of reference values for airborne sound, one-third-octave bands
© ISO 2020 – All rights reserved 5
---------------------- Page: 17 ----------------------
SIST EN ISO 717-1:2021
ISO 717-1:2020(E)
Key
f frequency, in Hz
L reference value, in dB
Figure 2 — Curve of reference values for airborne sound, octave bands
Table 4 — Sound level spectra to calculate the adaptation terms
Frequency Sound levels, L
i,j
Hz Spectrum No. 1 to calculate C Spectrum No. 2 to calculate C
One-third octave Octave One-third octave Octave
100 −29 −20
125 −26 −21 −20 −14
160 −23 −18
200 −21 −16
250 −19 −14 −15 −10
315 −17 −14
400 −15 −13
500 −13 −8 −12 −7
630 −12 −11
800 −11 −9
1 000 −10 −5 −8 −4
1 250 −9 −9

NOTE All levels are A weighted and the overall spectrum level is normalized to 0 dB.

6 © ISO 2020 – All rights reserved
---------------------- Page: 18 ----------------------
SIST EN ISO 717-1:2021
ISO 717-1:2020(E)
Table 4 (continued)
Frequency Sound levels, L
i,j
Hz Spectrum No. 1 to calculate C Spectrum No. 2 to calculate C
One-third octave Octave One-third octave Octave
1 600 −9 −10
2 000 −9 −4 −11 −6
2 500 −9 −13
3 150 −9 −15

NOTE All levels are A weighted and the overall spectrum level is normalized to 0 dB.

Key
f frequency, in Hz
L sound level at the frequency, i, for the spectrum, j, in dB
i,j
spectrum No. 1 to calculate C
spectrum No. 2 to calculate C
Figure 3 — Sound level spectra to calculate the spectrum adaptation terms for
one-third-octave band values
© ISO 2020 – All rights reserved 7
---------------------- Page: 19 ----------------------
SIST EN ISO 717-1:2021
ISO 717-1:2020(E)
Key
f frequency, in Hz
L sound level at the frequency, i, for the spectrum, j, in dB
i,j
spectrum No. 1 to calculate C
spectrum No. 2 to calculate C

Figure 4 — Sound level spectra to calculate the spectrum adaptation terms for octave band

measurements

An unfavourable deviation at a particular frequency occurs when the result of measurements is less

than the reference value. Only the unfavourable deviations shall be taken into account.

The value, in decibels (or 1/10 dB for the expression of uncertainty), of the reference curve at 500 Hz,

after shifting it in accordance with this procedure, is R , R′ , D or D , etc. (see Table 1 and Table 2).

w w n,w nT,w

Only reference values in octave bands shall be used for comparison with results of measurements in

octave bands in the field.
4.5 Calculation of spectrum adaptation terms

The spectrum adaptation terms, C , in decibels, shall be calculated with the sound spectra given in 4.3

from the following formula:
CX=−X (1)
jjAw
8 © ISO 2020 – All rights reserved
---------------------- Page: 20 ----------------------
SIST EN ISO 717-1:2021
ISO 717-1:2020(E)
where
j is the subscript for the sound spectra No. 1 and No.2;

X is the single-number quantity calculated according to 4.4 from R, R′, D or D values;

w n nT
X is calculated from
LX− /10
ij, i
X =−10lg∑10 dB (2)
in which

i is the subscript for the one-third-octave bands 100 Hz to 3 150 Hz or the octave

bands 125 Hz to 2 000 Hz;
L are the levels as given in 4.3 at the frequency, i, for the spectrum, j;
i,j
X is the sound reduction index, R , or apparent sound reduction index, R′ , or
i i i
normalized sound level difference, D , or standardized sound level difference,
n,i
D , at the measuring frequency i, given to one decimal place.
nT,i

Calculate the quantity, X , with sufficient accuracy and round the result to an integer (to one decimal

digit for the expression of uncertainty) . The resulting spectrum adaptation term is an integer by

definition and shall be identified in accordance with the spectrum used, as follows:

— C when calculated with spectrum No. 1 (A-weighted pink noise);
— C when calculated with spectrum No. 2 (A-weighted urban traffic noise).

NOTE 1 The spectra of most of the usual prevailing indoor and outdoor noise sources lie in the range of spectra

Nos. 1 and 2; the spectrum adaptation terms C and C can therefore be used to characterize the sound insulation

with respect to many types of noise. Guidelines for the relevant spectrum adaptation terms are given in Annex A.

NOTE 2 Supplementary calculations of the spectrum adaptation terms can also be carried out for the enlarged

frequency range (including 50 Hz + 63 Hz + 80 Hz and/or 4 000 Hz + 5 000 Hz one-third-octave bands or

63 Hz and/or 4 000 Hz octave bands). The relevant terms and spectra are given in Annex B. An example of the

calculation of the single-number quantity and the adaptation terms is given in Annex C.

5 Statement of results
5.1 General

The appropriate single-number quantity R , R′ , D or D and both adaptation terms shall be given

w w n,w nT,w

with reference to this document. The single number rating for improvement of sound reduction index

by linings shall be done as given in Annex D.
5.2 Statement of performance of building elements

Calculate the single-number quantity from one-third-octave bands only. State the two spectrum

adaptation terms in parentheses after the single-number quantity, separated by a semicolon.

2) XX,YZZ Z … is rounded to XX if Y is less than 5 and to XX + 1 if Y is greater than or equal to 5. For further

[1]

details, see ISO 80000-1 . Software implementers should be aware that calculation of the spectrum adaptation

terms involves floating-point calculations that are never exact and may incur rounding errors. In some rare cases,

this can lead to a difference of +1 dB or −1 dB in the final result. In order to avoid rounding errors, it is strongly

recommended that the highest possible machine accuracy available be used for floating-point represe

...

Questions, Comments and Discussion

Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.