Conservation of cultural heritage - Indoor climate - Part 2: Ventilation to protect heritage buildings and collections

The European Standard provides guidance for managing ventilation in heritage buildings, or buildings housing collections, in order to achieve adequate preservation of building fabric and objects they contain while at the same time creating an indoor environment that allows for a sustainable use of these buildings. The standard is a complement to existing general standards for ventilation in buildings focusing on human comfort.
This European Standard can also be used to support selection of heating strategies and heating systems for heritage buildings, or buildings housing collections (for guidelines for heating churches, chapels and other places of worship, see EN 15759-1).

Erhaltung des kulturellen Erbes - Raumklima - Teil 2: Lüftung für den Schutz von Gebäuden und Sammlungen des kulturellen Erbes

Die Europäische Norm stellt einen Leitfaden für die Regelung der Lüftung in Gebäuden des Kulturerbes oder in Gebäuden, die Sammlungen beherbergen, bereit, um die geeignete Konservierung der Bausubstanz und von im Gebäude enthaltenen Objekten zu erreichen, während gleichzeitig eine Innenraumumgebung erzeugt wird, die eine nachhaltige Nutzung dieser Gebäude ermöglicht. Die Norm ist eine Ergänzung zu bestehenden allgemeinen Normen zur Lüftung in Gebäuden, die den Schwerpunkt auf die Behaglichkeit für Menschen legen.
Diese Europäische Norm kann auch angewendet werden, um die Auswahl von Heizstrategien und Heizungsanlagen für Gebäude des Kulturerbes oder Gebäude, die Sammlungen beherbergen, zu unterstützen (für Leitfäden für die Beheizung von Andachtsstätten siehe EN 15759-1).

Conservation du patrimoine culturel - Climat intérieur - Partie 2 : Ventilation destinée à protéger les bâtiments et les collections appartenant au patrimoine

La présente norme fournit des préconisations concernant la gestion de la ventilation dans les bâtiments patrimoniaux ou abritant des collections. L'objectif est d'assurer une conservation adaptée de l'intérieur des bâtiments et de leurs biens. Il convient également de créer un environnement intérieur garantissant une utilisation durable de ces bâtiments. Elle complète les normes générales existantes relatives à la ventilation dans les bâtiments qui se concentrent sur le confort des utilisateurs.
La présente norme peut également être utilisée pour faciliter le choix des stratégies et des systèmes de chauffage des bâtiments patrimoniaux ou abritant des collections (pour les lignes directrices relatives au chauffage des églises, chapelles et autres édifices cultuels, voir l'EN 15759-1:2011).

Ohranjanje kulturne dediščine - Notranje okolje - 2. del: Prezračevanje za zaščito stavb in zbirk kulturne dediščine

General Information

Status
Published
Public Enquiry End Date
19-Mar-2016
Publication Date
22-Jan-2018
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
18-Jan-2018
Due Date
25-Mar-2018
Completion Date
23-Jan-2018

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Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN 15759-2:2018
01-marec-2018
2KUDQMDQMHNXOWXUQHGHGLãþLQH1RWUDQMHRNROMHGHO3UH]UDþHYDQMH]D]DãþLWR
VWDYELQ]ELUNNXOWXUQHGHGLãþLQH
Conservation of cultural heritage - Indoor climate - Part 2: Ventilation to protect heritage
buildings and collections
Erhaltung des kulturellen Erbes - Raumklima - Teil 2: Lüftung für den Schutz von
Gebäuden und Sammlungen des kulturellen Erbes
Conservation du patrimoine culturel - Climat intérieur - Partie 2 : Ventilation destinée à
protéger les bâtiments et les collections appartenant au patrimoine
Ta slovenski standard je istoveten z: EN 15759-2:2018
ICS:
91.140.30 3UH]UDþHYDOQLLQNOLPDWVNL Ventilation and air-
VLVWHPL conditioning systems
97.195 8PHWQLãNLLQREUWQLãNLL]GHONL Items of art and handicrafts.
.XOWXUQHGREULQHLQNXOWXUQD Cultural property and
GHGLãþLQD heritage
SIST EN 15759-2:2018 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 15759-2:2018

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SIST EN 15759-2:2018


EN 15759-2
EUROPEAN STANDARD

NORME EUROPÉENNE

January 2018
EUROPÄISCHE NORM
ICS 97.195
English Version

Conservation of cultural heritage - Indoor climate - Part 2:
Ventilation management for the protection of cultural
heritage buildings and collections
Conservation du patrimoine culturel - Climat intérieur Erhaltung des kulturellen Erbes - Raumklima - Teil 2:
- Partie 2 : Ventilation destinée à protéger les Lüftung für den Schutz von Gebäuden und
bâtiments et les collections appartenant au patrimoine Sammlungen des kulturellen Erbes
This European Standard was approved by CEN on 20 November 2017.

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, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, 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
© 2018 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 15759-2:2018 E
worldwide for CEN national Members.

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SIST EN 15759-2:2018
EN 15759-2:2018 (E)
Contents Page
European foreword . 4
Introduction . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Step-by-step approach to managing ventilation . 10
5 Analysis of ventilation-related risks . 11
5.1 General . 11
5.2 Ventilation-related risks . 11
5.2.1 General . 11
5.2.2 Excessive RH fluctuations . 12
5.2.3 High RH levels . 12
5.2.4 Low RH levels . 12
5.2.5 Moisture condensation . 12
5.2.6 Water evaporation and salt damage . 12
5.2.7 Transport and deposition of air pollutants . 12
5.3 Assessing the ventilation-related risks . 12
5.3.1 General . 12
5.3.2 Condition survey . 13
5.3.3 Determination of air exchange rate . 13
5.3.4 Assessment of indoor air quality . 13
6 Ventilation objective . 13
7 Requirements for indoor air quality . 14
7.1 General . 14
7.2 Indoor climate . 14
7.3 Air pollutants . 14
8 Ventilation management recommendations . 15
8.1 General . 15
8.2 Simple adjustments improving the indoor climate . 15
8.3 Technical installations . 15
8.4 Programmable control systems . 15
8.5 Monitoring systems . 16
8.6 Complementary measures . 16
8.6.1 General . 16
8.6.2 Preservation heating . 16
8.6.3 Humidification, dehumidification . 16
8.6.4 Showcases . 17
9 Ventilation management measures implementation . 17
10 Ventilation management measures evaluation . 17
Annex A (informative) Examples . 18
A.1 General . 18
2

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SIST EN 15759-2:2018
EN 15759-2:2018 (E)
A.2 Cultural heritage building housing a museum with a mixed collection . 18
A.3 Modern storage facility for archival and library materials using passive climate
control. 20
Annex B (informative) Technical aspects . 21
Bibliography . 22

3

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SIST EN 15759-2:2018
EN 15759-2:2018 (E)
European foreword
This document (EN 15759-2:2018) has been prepared by Technical Committee CEN/TC 346
“Conservation of Cultural Heritage”, the secretariat of which is held by UNI.
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 July 2018, and conflicting national standards shall be
withdrawn at the latest by July 2018.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN not be held responsible for identifying any or all such patent rights.
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, Former Yugoslav Republic of Macedonia,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta,
Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.
4

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SIST EN 15759-2:2018
EN 15759-2:2018 (E)
Introduction
The aim of the ventilation management is to ensure the optimum preservation of cultural heritage
buildings and collections, and to provide human comfort.
Indoor climate is influenced by the variations of outdoor climate and the properties of the building
envelope: air tightness, insulation and hygrothermal buffering. An inadequate indoor climate may result
to significant damage on buildings and their collections. Building operations such as opening of doors or
windows, presence of visitors, heating or cooling to ensure human comfort, or lighting with
incandescence lamps, also affect the indoor climate. Controlling the level of pollutants generated both
externally and internally could further improve indoor air quality.
Air exchange, in the form of active ventilation, natural ventilation and infiltration as well as internal air
circulation are only two of many factors whose complex interaction determines indoor climate;
however, they are fundamental for providing a conservation safe indoor environment. The aim of this
standard is to describe procedures for the ventilation management for the protection of cultural
heritage. However, environmentally induced risks can only be mitigated with an integrated risk
management plan of which ventilation is one element.
This standard is addressed to building owners, authorities and professionals involved in preservation,
conservation and refurbishment of cultural heritage buildings and their content, or modern buildings
housing collections. It aims at facilitating the sustainable management of these buildings by integrating
measures for energy performance and reduction of greenhouse gas emissions.
5

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SIST EN 15759-2:2018
EN 15759-2:2018 (E)
1 Scope
This European Standard gives guidelines for ventilation management in order to improve the
preservation conditions of cultural heritage buildings and their collections. At the same time, it is aimed
to create an indoor environment for a sustainable use of these buildings and their collections. This
standard is a complement to existing general standards for ventilation that are focused on human
comfort.
This European Standard is the second part of a standard on indoor climate in cultural heritage
buildings, i.e. EN 15759-1:2011. It should be used together with the first part when considering
selection of heating strategies and heating systems for cultural heritage buildings, or buildings housing
collections. It may be also used when considering other issues, e.g. assessment of buildings, interiors
and contents, or improvements for the energy performance.
This European Standard deals with indoor climate conditions, ventilation strategies and generic
technical solutions for their implementation but not with the technical equipment itself.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
EN 15757:2010, Conservation of Cultural Property — Specifications for temperature and relative
humidity to limit climate-induced mechanical damage in organic hygroscopic materials
EN 15758:2010, Conservation of Cultural Property — Procedures and instruments for measuring
temperatures of the air and the surfaces of objects
EN 15759-1:2011, Conservation of cultural property — Indoor climate — Part 1: Guidelines for heating
churches, chapels and other places of worship
EN 15898:2011, Conservation of cultural property — Main general terms and definitions
EN 16095, Conservation of cultural property — Condition recording for movable cultural heritage
EN 16096, Conservation of cultural property — Condition survey and report of built cultural heritage
EN 16242:2012, Conservation of cultural heritage — Procedures and instruments for measuring humidity
in the air and moisture exchanges between air and cultural property
EN ISO 12569, Thermal performance of buildings and materials — Determination of specific airflow rate
in buildings — Tracer gas dilution method (ISO 12569)
EN ISO 16000-1, Indoor air — Part 1: General aspects of sampling strategy (ISO 16000-1)
ISO 16000-8, Indoor air — Part 8: Determination of local mean ages of air in buildings for characterizing
ventilation conditions
3 Terms and definitions
For the purposes of this document, general terms and definitions concerning conservation of cultural
heritage given in EN 15898:2011 and the following apply.
6

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EN 15759-2:2018 (E)
3.1
air circulation
motion of air in a given space or through an opening
3.2
air exchange
air volume added to or removed from a space
Note 1 to entry: It can be due to ventilation or infiltration.
3
Note 2 to entry: This is expressed in m .
3.3
air exchange rate
rate at which air enters or leaves the building
Note 1 to entry: This is expressed as the volume of outdoor air passing an indoor space per hour, divided by the
−1
volume of the space, in air changes per hour, h .
3.4
air pollutant
material emitted into the atmosphere either by human activity or natural processes and adversely
affecting humans or the environment
[SOURCE: ISO 18158:2016, 2.1.2.1]
Note 1 to entry: In this standard, the adverse effects on cultural heritage are particularly relevant.
3.5
air temperature
T
temperature read on a thermometer which is exposed to air in a position sheltered from direct solar
radiation or other energy sources
Note 1 to entry: This is expressed in degrees Celsius (°C)
[SOURCE: EN 15758:2010, 3.1]
3.6
airborne particles
fine matter in solid or liquid form dispersed in air
[SOURCE: ISO 18158:2016, 2.1.2.3]
3.7
building fabric
basic structure of a building
3.8
conservation
measures and actions aimed at safeguarding cultural heritage while respecting its significance,
including its accessibility to present and future generations
Note 1 to entry: Conservation includes “preventive conservation”*, “remedial conservation”* and “restoration”*.
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EN 15759-2:2018 (E)
Note 2 to entry: Derived from IC OM-CC 2008 New Delhi Resolution.
Note 3 to entry: The intention is generally to ensure access, intellectual and/or physical, now and/or in the
future.
[SOURCE: EN 15898:2011, 3.3.1]
3.9
cultural heritage
tangible and intangible entities of significance to present and future generations
Note 1 to entry: Significance can derive from – among others – artistic, symbolic, historic, social, scientific or
technological factors.
[SOURCE: EN 15898:2011, 3.1.1]
3.10
dew-point temperature
temperature to which air is cooled at constant pressure and constant water vapour content in order for
saturation to occur
Note 1 to entry: This is expressed in degrees Celsius (°C).
[SOURCE: EN 15758:2010, 3.6]
3.11
heating, ventilating or air conditioning systems
HVAC systems
active systems operated to control air temperature (heating), air temperature and humidity (air
conditioning) or ventilation in a building
[SOURCE: EN 15757:2010, 3.4]
3.12
indoor climate
climate inside a room or a building
[SOURCE: EN 15759-1:2011, 3.8]
3.13
infiltration
unintentional or accidental introduction of outdoor air into a building through gaps in the building
envelope, often located in the frames and fittings of doors and windows
3.14
microclimate
climate in part of a building or a room where the climate differs from the surrounding climate
[SOURCE: EN 15759-1:2011, 3.11]
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EN 15759-2:2018 (E)
3.15
mixing ratio or humidity mixing ratio
MR
m
v
ratio of the mass of water vapour m to the mass of dry air m , i.e. MR= , expressed in g/kg
v a
m
a
[SOURCE: EN 16242:2012, 3.12]
3.16
natural ventilation
ventilation caused by environmental factors, e.g. wind, temperature and pressure differences, diffusion,
through doors, windows or other intentional openings in a building
3.17
outdoor climate
climate outside of the building
[SOURCE: EN 15759-1:2011, 3.14]
3.18
preservation heating
heating used to improve the indoor climate for preservation purposes
[SOURCE: EN 15759-1:2011, 3.1]
3.19
programmable control system
system that continuously measures climate parameters and then automatically steers technical devices
to correct deviations from pre-set values using individual algorithms
3.20
relative humidity
RH
ratio of the actual water vapour pressure to the saturation water vapour pressure
[SOURCE: EN 15757:2010, 3.9]
3.21
surface temperature
TS
temperature of a given surface of an object
[SOURCE: EN 15758:2010, 3.18]
Note 1 to entry: This can be measured with contact thermometers, quasi-contact total radiation thermometers
or remote infrared thermometers. The surface temperature is generally different from the air temperature, and
varies between different objects and different areas on the same object. It is expressed in degrees Celsius (°C). In
general, the measured surface temperature is not representative of the whole object.
3.22
ventilation
process of supplying outside air or removing inside air by natural or mechanical means to or from a
room or building
9

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EN 15759-2:2018 (E)
4 Step-by-step approach to managing ventilation
Each cultural heritage building has a particular, individual character, therefore, factors and areas of risk
as well as measures to address the risks should be identified by a team of specialists in building
construction and physics, air quality control and preventive conservation.
The following steps shall be carried out in the given order:
a) analyse present ventilation and identify related risks to the building, as well as to its content,
including collections;
b) determine the overall objective of the intervention;
c) define requirements for the indoor air temperature and humidity;
d) define requirements to limit indoor gaseous and particulate air pollutants, either of human or
natural origin;
e) prepare recommendations for the management of ventilation;
f) implement the recommended measures;
g) evaluate their effectiveness;
h) evaluate the impact of the intervention on the building and adapt its use if necessary.
A summary of the procedure for ventilation management in cultural heritage buildings, or buildings
housing collections, is provided in Table 1.
Table 1 — Summary of the procedure for ventilation management in cultural heritage buildings
or buildings housing collections
Required steps Purpose Activities
Step a To identify one or several risks 1)  Condition survey (see 5.3.2)
resulting from excessive or
Analyse present 2)  Determine air exchange rate (see
insufficient ventilation:
ventilation and identify 5.3.3)
related risks to the —  excessive RH fluctuations
3)  Assess indoor air quality (see 5.3.4)
building, as well as its (see 5.2.2)
content, including
—  high RH levels (see 5.2.3)
collections
—  low RH levels (see 5.2.4)

—  moisture condensation (see
5.2.5)
—  water evaporation and salt
damage (see 5.2.6)
—  transport and deposition of
air pollutants (see 5.2.7)
Step b To define clearly the reason for Assess the significance of building, its
the proposed intervention with interiors and contents as well as their
Determine the overall
respect to the use and vulnerability to change.
objective of the
preservation of the building, as
intervention Decide if the ventilation in the building
well as objects and collections it
needs to be kept unchanged or not (see
contains
Clause 6)
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EN 15759-2:2018 (E)
Required steps Purpose Activities
Step c To adequately address the Specify the strategy to improve the
ventilation-related threats indoor climate (see 7.2)
Define requirements for
identified
the indoor air Annex A - Examples of requirements for
temperature and the indoor air temperature and
humidity humidity
Step d  Specify the strategy to reduce the
impact of indoor pollution (see 7.3)
Define requirements to
limit indoor pollution
Step e To adequately address the Specify the following measures:
identified ventilation-related
Prepare 1)  Simple adjustments improving the
threats
recommendations for indoor climate (see 8.2)
the management of
2)  Technical devices (see 8.3)
ventilation
3)  Programmable control systems (see
8.4)
4)  Monitoring systems (see 8.5)
5)  Complementary measures (see 8.6)
Annex A – Examples of
recommendations for the management
of ventilation
Step f To achieve the required 1)  Analyse the impact on the building
ventilation strategy (see Clause 9)
Implement the
recommended 2)  Consider the technical aspects (see
measures Annex B)
3)  Analyse cost, energy efficiency and
sustainability
Steps g and h To evaluate the effectiveness of See Clause 10 to produce an evaluation
the implemented measures and
Evaluate the
their impact on the building
intervention
5 Analysis of ventilation-related risks
5.1 General
Ventilation constitutes an effective mechanism of distributing, removing or supplying heat, moisture
and air pollutants. This means that the consequences of ventilation may be positive or negative and the
use of ventilation should be carefully studied, implemented, managed and verified to take advantage of
it as a preventive conservation measure.
5.2 Ventilation-related risks
5.2.1 General
Risks may result from excessive or insufficient ventilation. The most frequently encountered risks are
encompassed in 5.2.2 to 5.2.7.
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EN 15759-2:2018 (E)
5.2.2 Excessive RH fluctuations
Uncontrolled natural ventilation can lead to excessive amplitude and/or frequency of fluctuations of
indoor RH (see EN 15757:2010 for guidance in specifying temperature and RH levels and variations to
limit climate-induced physical damage of objects containing moisture-sensitive materials).
5.2.3 High RH levels
In buildings with considerable internal moisture sources including large inflow of visitors, low air
exchange may cause high RH levels. Moist air entering a building may also cause high RH depending on
indoor temperature. The issue is especially pronounced in buildings with cold structures frequently
leading to moisture condensation described in 5.2.5. High RH increases the risk of mould growth, salt
deliquescence and hydration, hydrolysis-dominated deterioration of organic materials, metal oxidation
and corrosion or other deterioration mechanisms.
5.2.4 Low RH levels
When cold air enters a heated building indoor RH drops. Low RH levels are responsible for, or related
to, several deterioration mechanisms affecting objects of cultural heritage. Dry environments become
dusty and electrostatic deposition is enhanced. Hygroscopic materials (e.g. wood, paper, textiles, leather
or bone) release moisture in response to drops in RH, which produces shrinkage of the materials
leading to stress and physical damage as fracture and deformation.
5.2.5 Moisture condensation
Moisture condensation is due to coincidence of two factors: low surface temperatures and high
humidity mixing ratio of the air. This typically occurs in spring when warm (and moist) outdoor air
enters a stone or brick building with significant thermal inertia. Moisture condensation considerably
intensifies risk caused by high RH levels, as described in 5.2.3.
NOTE See EN ISO 13788 for formulas for calculation of the internal surface temperature of a building
component or building element below which mould growth is likely, given the internal temperature and relative
humidity.
5.2.6 Water evaporation and salt damage
High temperatures and/or air flows over wall surfaces created by excessive ventilation can increase
evaporation and, in consequence, capillary rise and salt crystallization.
5.2.7 Transport and deposition of air pollutants
Man-made gaseous air pollutants and airborne particles may have either outdoor or indoor sources, or
both. Poorly managed ventilation can cause an uncontrolled inflow of outdoor pollutants and/or
ineffective removal of the indoor generated pollutants. Outdoor air may also contain natural aerosols
e.g. sea spray, and organisms e.g. spores and pollens. High concentrations of spores may also be
generated in damp indoor environments. Thus, depending on the specific conditions, ventilation can
either decrease or increase the level of air pollutants.
Depending on the physical characteristics of the air and the building surfaces, air flows may increase
the deposition of air pollutants and, in this way, enhance surface deterioration, such as corrosion,
discoloration or deposits.
5.3 Assessing the ventilation-related risks
5.3.1 General
Risks that can be addressed by improved ventilation shall be identified by assessing the results of the
condition survey, measurements of the air exchange rates and assessment of the indoor air quality.
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EN 15759-2:2018 (E)
5.3.2 Condition survey
A condition survey to record damage occurred in the building, including furnishings or objects it
contains, shall be implemented in accordance with EN 16095 and EN 16096. The causes of the
prevailing damage types, especially those that may be related to the current indoor environmental
conditions, shall be carefully determined.
5.3.3 Determination of air exchange rate
Air exchange rate shall be estim
...

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