ISO/FDIS 17201-2

Acoustics — Noise from shooting ranges — Part 2: Calculation of muzzle blast

Acoustique — Bruit des stands de tir — Partie 2: Calcul de la détonation à la bouche

General Information

• Status: Not Published
• ICS: 17.140.20 - Noise emitted by machines and equipment
• ICS: 95.020 - Military in general
• ICS: 97.220.10 - Sports facilities
• Technical Committee: ISO/TC 43/SC 1 - Noise
• Drafting Committee: ISO/TC 43/SC 1 - Noise
• Current Stage: 5020 - FDIS ballot initiated: 2 months. Proof sent to secretariat
• Start Date: 11-Apr-2025
• Completion Date: 11-Apr-2025

Relations

• Revises: ISO 17201-2:2006 - Acoustics — Noise from shooting ranges — Part 2: Estimation of muzzle blast and projectile sound by calculation
• Effective Date: 06-Jun-2022

Standards Content (Sample)

FINAL DRAFT
International
Standard
ISO/TC 43/SC 1
Acoustics — Noise from shooting
Secretariat: DIN
ranges —
Voting begins on:
2025-04-11
Part 2:
Calculation of muzzle blast
Voting terminates on:
2025-06-06
Acoustique — Bruit des stands de tir —
Partie 2: Calcul de la détonation à la bouche
RECIPIENTS OF THIS DRAFT ARE INVITED TO SUBMIT,
WITH THEIR COMMENTS, NOTIFICATION OF ANY
RELEVANT PATENT RIGHTS OF WHICH THEY ARE AWARE
AND TO PROVIDE SUPPOR TING DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
ISO/CEN PARALLEL PROCESSING LOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT
INTERNATIONAL STANDARDS MAY ON OCCASION HAVE
TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL
TO BECOME STAN DARDS TO WHICH REFERENCE MAY BE
MADE IN NATIONAL REGULATIONS.
Reference number
FINAL DRAFT
International
Standard
ISO/TC 43/SC 1
Acoustics — Noise from shooting
Secretariat: DIN
ranges —
Voting begins on:
Part 2:
Calculation of muzzle blast
Voting terminates on:
Acoustique — Bruit des stands de tir —
Partie 2: Calcul de la détonation à la bouche
RECIPIENTS OF THIS DRAFT ARE INVITED TO SUBMIT,
WITH THEIR COMMENTS, NOTIFICATION OF ANY
RELEVANT PATENT RIGHTS OF WHICH THEY ARE AWARE
AND TO PROVIDE SUPPOR TING DOCUMENTATION.
© ISO 2025
IN ADDITION TO THEIR EVALUATION AS
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
ISO/CEN PARALLEL PROCESSING
LOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
INTERNATIONAL STANDARDS MAY ON OCCASION HAVE
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL
or ISO’s member body in the country of the requester.
TO BECOME STAN DARDS TO WHICH REFERENCE MAY BE
MADE IN NATIONAL REGULATIONS.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland Reference number
ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
3.1 General .1
3.2 Directivity . .3
3.3 Energy .3
3.4 Fraction .4
3.5 Projectile .5
4 Estimation model for source data of the muzzle blast . 5
4.1 General .5
4.2 Estimation of chemical energy .5
4.3 Estimation of acoustic energy . .6
4.4 Estimation of the Weber energy .6
4.5 Estimation of directivity .6
4.6 Estimation of the spectrum .6
5 Uncertainty of estimation . 7
6 Report . 8
Annex A (informative) Simple blast model for estimation of sound energy and its spectrum . 9
Annex B (informative) Quality of input data.11
Annex C (informative) Comparison between measurements and prediction of muzzle blast . 14
Bibliography .21

iii
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 document 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).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent
rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a)
patent(s) which may be required to implement this document. However, implementers are cautioned that
this may not represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
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 1, Noise, in
collaboration with the European Committee for Standardization (CEN) Technical Committee CEN/TC 211,
Acoustics, in accordance with the Agreement on technical cooperation between ISO and CEN (Vienna
Agreement).
This second edition cancels and replaces the first edition (ISO 17201-2:2006), which has been technically
revised.
The main changes are as follows:
— deletion of former Clauses 5 and 6, and Annex D which were moved to ISO 17201-4;
— revision of former Clause 7 (now Clause 5) and Annex C;
— addition of a new Clause 6;
— editorial revision of the document.
A list of all parts in the ISO 17201 series can be found on the ISO website.
The initiative to prepare a standard on impulse noise from shooting ranges was taken by AFEMS, the
Association of European Manufacturers of Sporting Ammunition, in April 1996, by the submission of a
formal proposal to CEN. After consultation in CEN in 1998, CEN/TC 211, Acoustics, asked ISO/TC 43/SC 1,
Noise, to prepare the ISO 17201 series.
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
Introduction
There are two basic sources that dominate the shooting sound from firearms: the muzzle blast and the
projectile sound. These two sources are basically different. The explosion blast from devices can be treated
as muzzle blast. This document describes the calculation of muzzle blast. The calculation of projectile sound
is described in ISO 17201-4.
The muzzle blast is caused by the expanding gases of the propellant at the muzzle. The muzzle blast can be
modelled approximately based on a spherical volume of these gases at that moment when the expansion
speed becomes subsonic.
In general, the procedures for estimating the muzzle blast rely on the estimation of energies that are
involved in the related processes. The procedures give estimates for the fraction of these energies that
transforms into acoustic energy. The results of the estimation are acoustical source data with respect to
energy, direction and frequency content.

v
FINAL DRAFT International Standard ISO/FDIS 17201-2:2025(en)
Acoustics — Noise from shooting ranges —
Part 2:
Calculation of muzzle blast
1 Scope
This document specifies a computational method (in line with ISO 17201-4) for estimating the acoustic
source data of muzzle blast and explosions on the basis of non-acoustic data for firearms with calibres less
than 20 mm and explosions less than 50 g TNT equivalent.
This document addresses those cases where no source measurements exist. This document can also be used
as an interpolation method between measurements of muzzle blast.
Source data are given in terms of spectral angular source energy covering the frequency range from 12,5 Hz
to 10 kHz and can be used as data input for sound propagation calculation.
This document does not apply to the prediction of sound levels for the assessment of hearing damage; nor
can it be used to predict sound pressure levels or sound exposure levels at distances where linear acoustics
do not apply.
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 17201-1, Acoustics — Noise from shooting ranges — Part 1: Determination of muzzle blast by measurement
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 17201-1 and the following apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1 General
3.1.1
air density
ρ
density of air for the estimation conditions
Note 1 to entry: The air density is expressed in kilograms per cubic metre (kg/m ).

3.1.2
angular frequency
ω
frequency multiplied by 2π
Note 1 to entry: The angular frequency is expressed in radians per second (rad/s) in all formulae.
3.1.3
cosine coefficients
c
1,2…N
coefficients of the cosine-transform used to describe the directivity of the angular source energy
3.1.4
specific chemical energy
u
specific chemical energy content of the propellant
Note 1 to entry: The specific chemical energy is usually expressed in joules per kilogram (J/kg).
3.1.5
sound exposure
E
time integral of frequency-weighted squared instantaneous sound pressure over the event duration time
Ep= ()ttd
∫
T
Note 1 to entry: The sound exposure is expressed in pascal-squared seconds (Pa ⋅s).
3.1.6
sound exposure level
L
E
ten times the logarithm to the base 10 of the ra
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Secretariat: DIN
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Date: 2025-03-14-xx
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Acoustics — Noise from shooting ranges —
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Line spacing: single
Commented [eXtyles1]: The reference "ISO 2025" is to a
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication
withdrawn standard
may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying,
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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.
Formatted: Default Paragraph Font
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ISO copyright office
Before: 0 pt, No page break before, Adjust space
CP 401 • Ch. de Blandonnet 8
between Latin and Asian text, Adjust space between
CH--1214 Vernier, Geneva
Asian text and numbers
Phone: + 41 22 749 01 11
EmailE-mail: [e-mail]
Website: www.iso.orgwww.iso.org
Published in Switzerland
Formatted: Font: 10 pt
Formatted: Font: 10 pt
Formatted: Font: 11 pt
Formatted: FooterPageRomanNumber, Space After: 0
pt, Line spacing: single
ii © ISO #### 2025 – All rights reserved
ii
Formatted: Font: Bold
Formatted: HeaderCentered, Left
Contents Formatted: Adjust space between Latin and Asian text,
Adjust space between Asian text and numbers
Foreword . v
Introduction . vii
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
3.1 General. 1
3.2 Directivity . 3
3.3 Energy . 3
3.4 Fraction . 5
3.5 Projectile . 5
4 Estimation model for source data of the muzzle blast . 5
4.1 General. 5
4.2 Estimation of chemical energy . 6
4.3 Estimation of acoustic energy . 6
4.4 Estimation of the Weber energy . 6
4.5 Estimation of directivity . 6
4.6 Estimation of the spectrum . 6
5 Uncertainty of estimation . 7
6 Report . 8
Annex A (informative) Simple blast model for estimation of sound energy and its spectrum . 9
Annex B (informative) Quality of input data . 12
Annex C (informative) Comparison between measurements and prediction of muzzle blast . 15
Bibliography . 22

Foreword . iv
Introduction . v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
3.1 General. 1
3.2 Directivity . 3
3.3 Energy . 3
Formatted: Font: 10 pt
3.4 Fraction . 4
3.5 Projectile . 5 Formatted: Font: 10 pt
Formatted: Font: 10 pt
4 Estimation model for source data of the muzzle blast . 5
4.1 General. 5
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4.2 Estimation of chemical energy . 6
Formatted: Font: 11 pt
4.3 Estimation of acoustic energy . 6
4.4 Estimation of the Weber energy . 6 Formatted: FooterPageRomanNumber, Left, Space
After: 0 pt, Line spacing: single
© ISO 2025 – All rights reserved
iii
ISO #####-#:####(X/FDIS 17201-2:2025(en) Formatted: Font: 11 pt, Bold
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Formatted: HeaderCentered, Left, Space After: 0 pt,
4.5 Estimation of directivity . 6
Line spacing: single
4.6 Estimation of the spectrum . 6
5 Uncertainty of estimation . 7
6 Report . 8
Annex A (informative) Simple blast model for estimation of sound energy and its spectrum . 9
Annex B (informative) Quality of input data . 11
B.1 Mass of explosives — Weber radius — Source energy level . 11
B.2 Lateral kinetic energy — Mass of propellant . 13
B.3 Specific chemical energy — Temperature . 13
B.4 Weber radius — Sound exposure measurements . 13
Annex C (informative) Comparison between measurements and prediction of muzzle blast . 14
C.1 Estimation procedure for muzzle blast source data by measurement. 14
C.1.1 Test plan of the measurement. 14
C.1.2 Description of procedure to calculate the free field data (see Table C.1) . 15
C.1.3 Description of procedure for calculating source energy level evaluated on basis of
angular source energy. 15
C.2 Estimation of source energy by prediction. 17
C.3 Comparison of measured and predicted source energy . 18
Bibliography . 22
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iv © ISO #### 2025 – All rights reserved
iv
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Formatted: HeaderCentered, Left
Foreword Formatted: Adjust space between Latin and Asian text,
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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
Formatted: English (United Kingdom)
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
Commented [eXtyles2]: The URL
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
https://www.iso.org/patents has been redirected to
http://www.iso.org/iso-standards-and-patents.html. Please
The procedures used to develop this document and those intended for its further maintenance are described
verify the URL.
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types of
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ISO document should be noted. This document was drafted in accordance with the editorial rules of the
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ISO/IEC Directives, Part 2 (see www.iso.org/directives).
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ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
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patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent rights
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in respect thereof. As of the date of publication of this document, ISO had not received notice of (a) patent(s)
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which may be required to implement this document. However, implementers are cautioned that this may not
represent the latest information, which may be obtained
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