Acoustics - Determination and application of measurement uncertainties in building acoustics - Part 1: Sound insulation (ISO 12999-1:2020)

This document specifies procedures for assessing the measurement uncertainty of sound insulation in building acoustics. It provides for
— a detailed uncertainty assessment;
— a determination of uncertainties by inter-laboratory tests;
— an application of uncertainties.
Furthermore, typical uncertainties are given for quantities determined according to ISO 10140 (all parts), ISO 16283 (all parts) and ISO 717 (all parts).

Akustik - Bestimmung und Anwendung der Messunsicherheiten in der Bauakustik - Teil 1: Schalldämmung (ISO 12999-1:2020)

Dieses Dokument legt Verfahren zur Beurteilung der Messunsicherheit der Schalldämmung in der Bauakustik fest. Es stellt Folgendes bereit:
- eine ausführliche Beurteilung der Unsicherheit;
- eine Bestimmung der Unsicherheiten durch Ringversuche;
- eine Anwendung der Unsicherheiten.
Darüber hinaus werden typische Unsicherheiten für nach ISO 10140 (alle Teile), ISO 16283 (alle Teile) und ISO 717 (alle Teile) be¬stimmte Größen angegeben.

Acoustique - Détermination et application des incertitudes de mesure dans l'acoustique des bâtiments - Partie 1: Isolation acoustique (ISO 12999-1:2020)

Le présent document spécifie des méthodes permettant d'évaluer l'incertitude de mesure de l'isolement acoustique dans le domaine de l'acoustique des bâtiments. Il prévoit:
— l'évaluation détaillée de l'incertitude;
— la détermination des incertitudes par des essais interlaboratoires;
— l'application des incertitudes.
En outre, des incertitudes caractéristiques sont données pour les grandeurs déterminées conformément à l'ISO 10140 (toutes les parties), l'ISO 16283 (toutes les parties) et l'ISO 717 (toutes les parties).

Akustika - Ugotavljanje in uporaba merilne negotovosti v gradbeni akustiki - 1. del: Zvočna izolirnost (ISO 12999-1:2020)

General Information

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

RELATIONS

Buy Standard

Standard
EN ISO 12999-1:2021
English language
29 pages
sale 10% off
Preview
sale 10% off
Preview

e-Library read for
1 day

Standards Content (sample)

SLOVENSKI STANDARD
SIST EN ISO 12999-1:2021
01-marec-2021
Nadomešča:
SIST EN ISO 12999-1:2014

Akustika - Ugotavljanje in uporaba merilne negotovosti v gradbeni akustiki - 1. del:

Zvočna izolirnost (ISO 12999-1:2020)

Acoustics - Determination and application of measurement uncertainties in building

acoustics - Part 1: Sound insulation (ISO 12999-1:2020)

Akustik - Bestimmung und Anwendung der Messunsicherheiten in der Bauakustik - Teil

1: Schalldämmung (ISO 12999-1:2020)

Acoustique - Détermination et application des incertitudes de mesure dans l'acoustique

des bâtiments - Partie 1: Isolation acoustique (ISO 12999-1:2020)
Ta slovenski standard je istoveten z: EN ISO 12999-1:2020
ICS:
17.140.01 Akustična merjenja in Acoustic measurements and
blaženje hrupa na splošno noise abatement in general
91.120.20 Akustika v stavbah. Zvočna Acoustics in building. Sound
izolacija insulation
SIST EN ISO 12999-1:2021 en

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

---------------------- Page: 1 ----------------------
SIST EN ISO 12999-1:2021
---------------------- Page: 2 ----------------------
SIST EN ISO 12999-1:2021
EN ISO 12999-1
EUROPEAN STANDARD
NORME EUROPÉENNE
November 2020
EUROPÄISCHE NORM
ICS 17.140.01; 91.120.20 Supersedes EN ISO 12999-1:2014
English Version
Acoustics - Determination and application of measurement
uncertainties in building acoustics - Part 1: Sound
insulation (ISO 12999-1:2020)

Acoustique - Détermination et application des Akustik - Bestimmung und Anwendung der

incertitudes de mesure dans l'acoustique des Messunsicherheiten in der Bauakustik - Teil 1:

bâtiments - Partie 1: Isolation acoustique (ISO 12999- Schalldämmung (ISO 12999-1:2020)

1:2020)
This European Standard was approved by CEN on 21 October 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 12999-1:2020 E

worldwide for CEN national Members.
---------------------- Page: 3 ----------------------
SIST EN ISO 12999-1:2021
EN ISO 12999-1:2020 (E)
Contents Page

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

---------------------- Page: 4 ----------------------
SIST EN ISO 12999-1:2021
EN ISO 12999-1:2020 (E)
European foreword

This document (EN ISO 12999-1:2020) 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 May 2021, and conflicting national standards shall be

withdrawn at the latest by May 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 12999-1:2014.

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 12999-1:2020 has been approved by CEN as EN ISO 12999-1:2020 without any

modification.
---------------------- Page: 5 ----------------------
SIST EN ISO 12999-1:2021
---------------------- Page: 6 ----------------------
SIST EN ISO 12999-1:2021
INTERNATIONAL ISO
STANDARD 12999-1
Second edition
2020-04
Acoustics — Determination and
application of measurement
uncertainties in building acoustics —
Part 1:
Sound insulation
Acoustique — Détermination et application des incertitudes de
mesure dans l'acoustique des bâtiments —
Partie 1: Isolation acoustique
Reference number
ISO 12999-1:2020(E)
ISO 2020
---------------------- Page: 7 ----------------------
SIST EN ISO 12999-1:2021
ISO 12999-1:2020(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
Fax: +41 22 749 09 47
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO 2020 – All rights reserved
---------------------- Page: 8 ----------------------
SIST EN ISO 12999-1:2021
ISO 12999-1:2020(E)
Contents Page

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

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

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

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

3 Terms and definitions ..................................................................................................................................................................................... 1

4 Detailed uncertainty budget .................................................................................................................................................................... 3

5 Uncertainty determination by inter-laboratory measurements ........................................................................ 3

5.1 General ........................................................................................................................................................................................................... 3

5.2 Measurement situations ................................................................................................................................................................. 3

5.3 Measurement conditions ......... ....................................................................................................................................................... 3

5.4 Number of participating laboratories ................................................................................................................................. 4

5.5 Stating the test results of inter-laboratory measurements .............................................................................. 4

5.6 Choice of test specimen ................................................................................................................................................................... 4

5.6.1 General...................................................................................................................................................................................... 4

5.6.2 Use of single test specimen — Same material circulated among participants ........... 4

5.6.3 Use of several test specimens taken from a production lot — Nominally

identical material exchangeable among participants ...................................................................... 5

5.6.4 Use of several test specimens constructed in-situ — Nominally identical

material not exchangeable among participants .................................................................................... 5

5.7 Laboratories with outlying measurement results .................................................................................................... 5

5.8 Verification of laboratory results by results of inter-laboratory tests .................................................... 5

6 Uncertainties associated with single-number values .................................................................................................... 6

7 Standard uncertainties for typical measurands .................................................................................................................. 7

7.1 General ........................................................................................................................................................................................................... 7

7.2 Airborne sound insulation ............................................................................................................................................................ 7

7.3 Impact sound insulation ................................................................................................................................................................. 8

7.4 Reduction of transmitted impact noise by floor coverings ............................................................................... 9

8 Application of the uncertainties ........................................................................................................................................................10

Annex A (informative) Example of handling uncertainties in building acoustics ..............................................12

Annex B (informative) Example for the calculation of the uncertainty of single number values ......14

Annex C (informative) Detailed uncertainty budget .........................................................................................................................17

Annex D (informative) Upper limit for the standard deviation of reproducibility for

airborne sound insulation .......................................................................................................................................................................19

Bibliography .............................................................................................................................................................................................................................21

© ISO 2020 – All rights reserved iii
---------------------- Page: 9 ----------------------
SIST EN ISO 12999-1:2021
ISO 12999-1:2020(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 second edition cancels and replaces the first edition (ISO 12999-1:2014), which has been technically

revised.
The main changes compared to the previous edition are as follows:
— the quantity σ was removed from Table 2;
R95

— the text in Clause 7 referring to this quantity was removed and the wording adapted;

— a new Annex D was drafted with a new table containing σ and text explaining what it is;

R95
— new references were added.
A list of all parts in the ISO 12999 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 12999-1:2021
ISO 12999-1:2020(E)
Introduction

An assessment of uncertainties that is comprehensible and close to reality is indispensable for many

questions in building acoustics. Whether a requirement is met, a laboratory delivers correct results

or the acoustic properties of a product are better than the same properties of some other product

can be decided only by adequately assessing the uncertainties associated with the quantities under

consideration.

Uncertainties should preferably be determined following the principles of ISO/IEC Guide 98-3. This

Guide specifies a detailed procedure for the uncertainty evaluation that is based upon a complete

mathematical model of the measurement procedure. At the current knowledge, it seems to be

impossible to formulate these models for the different quantities in building acoustics. Therefore, only

the principles of such an uncertainty assessment are explained.

To come to uncertainties all the same, the concept of reproducibility and repeatability is incorporated

which is the traditional approach for uncertainty determination in building acoustics. This concept

offers the possibility to state the uncertainty of a method and of measurements carried out according

to the method, based on the results of inter-laboratory measurements.

NOTE Whenever applicable, the terms and definitions used in this document are equivalent to those given in

[2] [7] [8]
ISO 5725-1 , in ISO/IEC Guide 98-3 and in ISO/IEC Guide 99 .
© ISO 2020 – All rights reserved v
---------------------- Page: 11 ----------------------
SIST EN ISO 12999-1:2021
---------------------- Page: 12 ----------------------
SIST EN ISO 12999-1:2021
INTERNATIONAL STANDARD ISO 12999-1:2020(E)
Acoustics — Determination and application of
measurement uncertainties in building acoustics —
Part 1:
Sound insulation
1 Scope

This document specifies procedures for assessing the measurement uncertainty of sound insulation in

building acoustics. It provides for
— a detailed uncertainty assessment;
— a determination of uncertainties by inter-laboratory tests;
— an application of uncertainties.

Furthermore, typical uncertainties are given for quantities determined according to ISO 10140 (all parts),

ISO 16283 (all parts) and ISO 717 (all parts).
2 Normative references
There are no normative references in this document.
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
measurand
particular quantity subject to measurement

EXAMPLE 1 The airborne sound insulation of a particular window pane determined in accordance with

ISO 10140 (all parts).

EXAMPLE 2 The standardized level difference of a particular facade according to ISO 16283-3.

3.2
measurement result

value attributed to a measurand (3.1), obtained by following the complete set of instructions given in a

measurement procedure

Note 1 to entry: The measurement result may be a frequency band level or a single number value determined

according to the rating procedures of ISO 717 (all parts).
© ISO 2020 – All rights reserved 1
---------------------- Page: 13 ----------------------
SIST EN ISO 12999-1:2021
ISO 12999-1:2020(E)
3.3
uncertainty

parameter, associated with the measurement result (3.2), that characterizes the dispersion of the values

that can reasonably be attributed to the measurand (3.1)
3.4
standard uncertainty

uncertainty (3.3) of the measurement result (3.2) expressed as a standard deviation

3.5
combined standard uncertainty

standard uncertainty (3.4) of the result of a measurement when that result is obtained from the values

of a number of other quantities, equal to the positive square root of a sum of terms, the terms being the

variances or covariances of these other quantities weighted according to how the measurement result

(3.2) varies with changes in these quantities
3.6
expanded uncertainty

quantity defining an interval about the measurement result (3.2) that can be expected to encompass a

large fraction of the distribution of values that can reasonably be attributed to the measurand (3.1)

3.7
coverage factor

numerical factor used as a multiplier of the combined standard uncertainty (3.5) in order to obtain an

expanded uncertainty (3.6)
3.8
repeatability condition

condition of measurement that includes the same measurement procedure, same operators, same

measuring system, same location (laboratory or usual building), and replicate measurements on the

same object over a short period of time
3.9
repeatability standard deviation

standard deviation of measurement results (3.2) obtained under repeatability conditions (3.8)

3.10
reproducibility condition

condition of measurement that includes the same measurement procedure, different locations

(laboratories or usual buildings), operators, measuring systems, and replicate measurements on the

same or similar objects
3.11
reproducibility standard deviation

standard deviation of measurement results (3.2) obtained under reproducibility conditions (3.10)

3.12
in-situ condition

condition of measurement that includes the same location (laboratory or usual building), and replicate

measurements on the same object by different operators using different measuring systems

2 © ISO 2020 – All rights reserved
---------------------- Page: 14 ----------------------
SIST EN ISO 12999-1:2021
ISO 12999-1:2020(E)
3.13
in-situ standard deviation
situ

standard deviation of measurement results (3.2) obtained under in-situ conditions (3.12)

4 Detailed uncertainty budget

The derivation of a detailed uncertainty budget is desirable to find out which uncertainty contributions

are the most important ones and how these contributions can be reduced. Furthermore, such a budget

reflects the individual sound fields during the measurement. Consequently, the uncertainty is valid for

an individual measurement result and not for a whole family of results. Annex C gives provisions on the

derivation of such uncertainty budgets.
5 Uncertainty determination by inter-laboratory measurements
5.1 General

Standard deviations determined by inter-laboratory measurements may serve as an estimate for

the standard uncertainty. The general concept and the procedure for determining these standard

deviations are given in ISO 5725-1 and ISO 5725-2, respectively. As many operators and laboratories as

possible should participate in such inter-laboratory measurements in order to obtain reliable results.

5.2 Measurement situations

In building acoustics, three different measurement situations are to be distinguished.

a) Situation A is that a building element is characterized by laboratory measurements. In this case, the

measurand is defined by the relevant part of ISO 10140, including all additional requirements, e.g.

for the measurement equipment and especially for the test facilities. Therefore, all measurement

results that are obtained in another test facility or building also comply with this definition. The

standard uncertainty, thus, is the standard deviation of reproducibility as determined by inter-

laboratory measurements.

b) Situation B is described by the case that different measurement teams come to the same location

to carry out measurements. The location may be a usual building or a test facility. The measurand,

thus, is a property of one particular element in one particular test facility or the property of a

building. The main difference from situation A is that many aspects of the airborne and structure-

borne sound fields involved remain constant since the physical construction is unchanged. The

standard uncertainty obtained for this situation is called in-situ standard deviation.

c) Situation C applies to the case when the measurement is simply repeated in the same location

by the same operator using the same equipment. The location may be a usual building or a test

facility. The standard uncertainty is the standard deviation of repeatability as determined by inter-

laboratory measurements.
5.3 Measurement conditions

The acoustical measurement conditions for determining the different standard deviations shall

correspond to the conditions given in the standardized measurement procedures. The test specimen

shall not be remounted between repeated measurements.

Each laboratory shall use its normal measurement procedure when participating in an inter-

laboratory measurement. No deviations from the test procedure laid down shall occur but repeating

the measurements several times, the parameters left open in the measurement procedure shall be

represented as well as possible. In particular, the set of microphone positions and source positions over

which averaging is carried out for one measurement shall be selected anew, more or less randomly,

© ISO 2020 – All rights reserved 3
---------------------- Page: 15 ----------------------
SIST EN ISO 12999-1:2021
ISO 12999-1:2020(E)

for each repeated measurement. This is necessary to obtain a mean value and a standard deviation of

repeatability that represent the situation correctly.

Before the inter-laboratory measurement is started, each participating laboratory shall report the

exact details of its test procedure.

Additional requirements for carrying out inter-laboratory measurements for the test specimen chosen

shall be laid down in detail. This refers in particular to the following items:
— quantities being measured and reported, rules for rounding numbers;
— number of repeated measurements required;
— calibration of the measurement equipment;

— mounting and sealing conditions of the test specimen, and curing time where appropriate.

5.4 Number of participating laboratories

The number of laboratories, p, shall, from a statistical point of view, be at least eight, but is preferable

to exceed this number in order to reduce the number of replicate measurements required. The number

of measurements in each laboratory, n, should be so chosen that p(n − 1) ≥ 35. In addition, at least

five test results are needed for each laboratory. If the number n of measurements is different among

the participating laboratories, a mean number of measurements shall be calculated and used (see

ISO 5725-2). The measurement results obtained shall not be pre-selected in any way by the participating

laboratories before they are reported.
5.5 Stating the test results of inter-laboratory measurements

In order to simplify the evaluation of measurement results reported, it is strongly desirable to supply

forms for filling in by the participants. For the statistical analysis, it is important to report special

observations and/or any irregularities observed during the test.
5.6 Choice of test specimen
5.6.1 General

The kind of test specimen used for an inter-laboratory measurement depends not only on the

quantity being tested (i.e. airborne sound reduction index, normalized impact sound pressure level)

but specifically on the mounting and measurement conditions for which the standard deviation of

repeatability and reproducibility are being obtained (e.g. walls, floors, windows). Effects influencing

the measurement result, like ageing or a strong dependence on humidity or temperature, shall also be

considered.

The choice of test specimen also depends on practical considerations. In general, three different

approaches (see 5.6.2 to 5.6.4) depending on the type of measurement method and/or on the type of

specimen can be appropriate.
5.6.2 Use of single test specimen — Same material circulated among participants

For checking the measurement procedure and the facilities in different laboratories, ideally, the same

test specimen should be used by all participants in the inter-laboratory measurement and checked

again by the first laboratory at the end of the inter-laboratory measurement.

In building acoustics, this procedure is often not feasible due to the long period of time required,

the risk of damage or change of the test specimen and different sizes of test openings. However, the

variability resulting from the use of more than one test specimen is avoided and the standard deviation

of reproducibility thus obtained is characteristic for the test facility and measurement procedure alone.

4 © ISO 2020 – All rights reserved
---------------------- Page: 16 ----------------------
SIST EN ISO 12999-1:2021
ISO 12999-1:2020(E)

5.6.3 Use of several test specimens taken from a production lot — Nominally identical material

exchangeable among participants

In contrast to the procedure described in 5.6.2, all participants of the inter-laboratory measurement

receive nominally identical test specimens, i.e. coming from the same production lot or of identical

design and constructed by one manufacturer. This enables testing in parallel and reduces the risk of

damage or of change due to the influence of time. However, the variability among the test specimens

due to their heterogeneity is then inseparable from the variability of the measurement procedure and

forms an inherent part of the reproducibility standard deviation. For this reason, it can be advantageous

to check all test specimens for homogeneity with more precision at one laboratory before the inter-

laboratory measurement and possibly also after its completion.

5.6.4 Use of several test specimens constructed in-situ — Nominally identical material not

exchangeable among participants

When the test specimens cannot be prefabricated and readily transported, they shall be constructed

in-situ by each participant according to close specifications. In this case, the variability among the test

specimens due to their heterogeneity is even larger than for test specimens according to 5.6.3.

5.7 Laboratories with outlying measurement results

ISO 5725-2 provides statistical methods to test whether a result of a laboratory is an outlier in a

statistical sense. If a result turns out to be an outlier, it is necessary to investigate what are the reasons

for the discrepancy. A result shall be disqualified only in the case that an error has occurred, e.g. a

wrong microphone sensitivity was used. Whenever the measurement procedure described in the

standard has been applied correctly and all the requirements
...

Questions, Comments and Discussion

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