Railway applications - Welding of railway vehicles and components - Part 4: Production requirements

This series of standards applies to welding of metallic materials in the manufacture and maintenance of railway vehicles and their parts.
This part of the series describes the production requirements (i.e. preparation and execution) of the welding work.

Bahnanwendungen - Schweißen von Schienenfahrzeugen und -fahrzeugteilen - Teil 4: Fertigungsanforderungen

Applications ferroviaires - Soudage des véhicules et des composants ferroviaires - Partie 4: Exigences de production

Železniške naprave - Varjenje železniških vozil in komponent - 4. del: Zahteve za proizvodnjo

General Information

Status
Not Published
Public Enquiry End Date
28-Oct-2020
Technical Committee
Current Stage
4020 - Public enquire (PE) (Adopted Project)
Start Date
13-Aug-2020
Due Date
31-Dec-2020
Completion Date
26-Oct-2020

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SLOVENSKI STANDARD
oSIST prEN 15085-4:2020
01-oktober-2020

Železniške naprave - Varjenje železniških vozil in elementov - 4. del: Zahteve za

proizvodnjo

Railway applications - Welding of railway vehicles and components - Part 4: Production

requirements
Bahnanwendungen - Schweißen von Schienenfahrzeugen und -fahrzeugteilen - Teil 4:
Fertigungsanforderungen

Applications ferroviaires - Soudage des véhicules et des composants ferroviaires - Partie

4: Exigences de production
Ta slovenski standard je istoveten z: prEN 15085-4
ICS:
25.160.10 Varilni postopki in varjenje Welding processes
45.060.01 Železniška vozila na splošno Railway rolling stock in
general
oSIST prEN 15085-4:2020 en,fr,de

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

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oSIST prEN 15085-4:2020
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oSIST prEN 15085-4:2020
DRAFT
EUROPEAN STANDARD
prEN 15085-4
NORME EUROPÉENNE
EUROPÄISCHE NORM
August 2020
ICS 25.160.10; 45.060.01 Will supersede EN 15085-4:2007
English Version
Railway applications - Welding of railway vehicles and
components - Part 4: Production requirements

Applications ferroviaires - Soudage des véhicules et des Bahnanwendungen - Schweißen von

composants ferroviaires - Partie 4: Exigences de Schienenfahrzeugen und -fahrzeugteilen - Teil 4:

production Fertigungsanforderungen

This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee

CEN/TC 256.

If this draft becomes a European Standard, 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.

This draft European Standard was established by CEN 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.

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 supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without

notice and shall not be referred to as a European Standard.
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. prEN 15085-4:2020 E

worldwide for CEN national Members.
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Contents Page

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

Introduction .................................................................................................................................................................... 4

1 Scope .................................................................................................................................................................... 5

2 Normative references .................................................................................................................................... 5

3 Terms and definitions ................................................................................................................................... 6

4 Preparation before welding ........................................................................................................................ 6

4.1 Welding planning documents ..................................................................................................................... 6

4.2 Production weld tests .................................................................................................................................... 9

5 Requirements for welding ........................................................................................................................ 12

5.1 General ............................................................................................................................................................. 12

5.2 General requirements ................................................................................................................................ 12

5.3 Welding consumables ................................................................................................................................. 15

5.4 Parent metals ................................................................................................................................................. 15

5.5 Welding processes ....................................................................................................................................... 17

Annex A (informative) Guidance to choose welding consumables ......................................................... 19

Annex ZA (informative) Relationship between this European Standard and the Essential

Requirements of EU Directive 2016/797/EU aimed to be covered ........................................... 23

Bibliography ................................................................................................................................................................. 25

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European foreword

This document (prEN 15085-4:2020) has been prepared by Technical Committee CEN/TC 256 “Railway

applications”, the secretariat of which is held by DIN.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 15085-4:2007.

This series of European Standards EN 15085 “Railway applications – Welding of railway vehicles and

components” consists of the following parts:
— Part 1: General;
— Part 2: Requirements for welding manufacturers;
— Part 3: Design requirements;
— Part 4: Production requirements;
— Part 5: Inspection, testing and documentation;
— Part 6: Maintenance welding requirements.

This document has been prepared under a mandate given to CEN by the European Commission and the

European Free Trade Association, and supports essential requirements of EU Directive(s).

For relationship with EU Directive(s), see informative Annex ZA, B, C or D, which is an integral part of this

document.
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Introduction

Welding is a special process in the manufacture of railway vehicles and their parts. The required

provisions for this process are laid down in the standards series EN ISO 3834. The basis of these

provisions are the basic technical welding standards in respect of the special requirements for the

construction of railway vehicles.

This document is aimed at defining the terms of enforcement applicable to European Standards, it should

not be construed as a substitute to these standards.

This document can also be used by internal and external parties to assess the organization's ability to

meet customer, regulatory, and the organization's own requirements.
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1 Scope

This document describes the production requirements (i.e. preparation and execution) of the welding

work.
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.

EN 1011 (all parts), Welding — Recommendations for welding of metallic material
EN 287-6, Qualification test of welders - Fusion welding - Part 6: Cast irons
EN 10204, Metallic products - Types of inspection documents

EN 13479, Welding consumables - General product standard for filler metals and fluxes for fusion welding

of metallic materials

EN 14532-1, Welding consumables - Test methods and quality requirements - Part 1: Primary methods and

conformity assessment of consumables for steel, nickel and nickel alloys

EN 14532-2, Welding consumables - Test methods and quality requirements - Part 2: Supplementary

methods and conformity assessment of consumables for steel, nickel and nickel alloys

EN 15085-1, Railway applications — Welding of railway vehicles and components — Part 1: General

EN 15085-3:2007, Railway applications — Welding of railway vehicles and components — Part 3: Design

requirements

EN 15085-5, Railway applications - Welding of railway vehicles and components - Part 5: Inspection, testing

and documentation

EN ISO 544, Welding consumables - Technical delivery conditions for filler materials and fluxes - Type of

product, dimensions, tolerances and markings (ISO 544:2017)

EN ISO 4063:2010, Welding and allied processes — Nomenclature of processes and reference numbers

EN ISO 9606 (all parts), Qualification test of welders — Fusion welding
EN ISO 14555, Welding - Arc stud welding of metallic materials (ISO 14555)

EN ISO 14732, Welding personnel - Qualification testing of welding operators and weld setters for

mechanized and automatic welding of metallic materials (ISO 14732)

EN ISO 15609 (all parts), Specification and qualification of welding procedures for metallic materials —

Welding procedure specification

EN ISO 15613, Specification and qualification of welding procedures for metallic materials - Qualification

based on pre-production welding test (ISO 15613)
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EN ISO 15614-(all parts), Specification and qualification of welding procedures for metallic materials —

Welding procedure test
EN ISO 15620, Welding - Friction welding of metallic materials (ISO 15620)

EN ISO 17652-1, Welding - Test for shop primers in relation to welding and allied processes - Part 1: General

requirements (ISO 17652-1)

EN ISO 17652-2, Welding - Test for shop primers in relation to welding and allied processes - Part 2: Welding

properties of shop primers (ISO 17652-2)
3 Terms and definitions

For the purposes of this document, the terms and definitions given in EN 15085-1 apply.

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

— ISO Online browsing platform: available at http://www.iso.org/obp
— IEC Electropedia: available at http://www.electropedia.org/
4 Preparation before welding
4.1 Welding planning documents
4.1.1 General

Welding planning documents shall be prepared by the manufacturer with the assistance of the

responsible welding coordinator. Type, scope and time of the submission and inspection should be

defined in the technical specification.

Welding planning documents may include working plans, welding sequence plans, test planning

documents, and welding procedure specifications.

Design documents of welded components shall be checked by the responsible welding coordinator or one

of his deputies about their suitability. If necessary – the design documents can be adapted for the

manufacturing under the supervision of the responsible welding coordinator, e.g. by changing chamfer

angle of the weld preparation to achieve the required weld quality.

The following changes shall not be done without a permission of the design office:

— weld type;
— weld performance class;
— weld inspection class;
— base material;
— properties of the weld metal;
— reduction of weld throat thickness;

For railway applications, only EN ISO 15614-1, EN ISO 15614-2, EN ISO 15614-3, EN ISO 15614-4,

EN ISO 15614-7, EN ISO 15614-11, EN ISO 15614-12, and EN ISO 15614-13 are relevant.

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— location of the weld;
— addition of welded joints;
— elimination of welded joints.

After a successful check and possible adaptation, the design documents can be included in the welding

planning documents. The weld preparation should be finally defined during design review and this

definition shall be documented.
4.1.2 Working plans

For the production of railway vehicles, it is necessary to have working plans for the following sub-

assemblies:
— bogie (sub-assemblies, assembly);
— underframe (with sub-assemblies);
— car body components (side wall, end wall, roof);
— car body assembly;

— further sub-assemblies with high safety and functional requirements (e.g. cardan shafts, brake cross

members, motor housing, hollow shaft drive, drawbar coupling, bogie pivot pin, cross bearer).

4.1.3 Other welding planning documents

For more complicated assemblies welding sequence plans may be necessary to reduce residual stresses

or deformation and shrinkage or to avoid missing welds e.g. for:
— bogie frames and their components, and
— underframes and their components.

Standardized welding sequence plans (that applies for different types of components) are also allowed.

Furthermore, other welding planning documents may be necessary (e.g. tacking sequence plans,

repairing plans, documents for jigs and tools, plans for separating of damaged parts, special instructions

for electronic parts). These details shall be determined by the responsible welding coordinator and/or

the customer.
The test plan shall be done in accordance with EN 15085-5:2007, Clause 6.
4.1.4 Welding procedure specification

For weld performance classes CP B1, CP B2, CP C1, CP C2 or CP C3 each weld shall be covered by WPS

according to the relevant part of EN ISO 15609, EN ISO 14555 or EN ISO 15620.
For weld performance class CP D a welding instruction shall exist.

For weld performance classes CP B1, CP B2, CP C1 or CP C2 an evidence by WPQR according to

EN ISO 15613, to EN ISO 15614 series, for EN ISO 15614-1 only level 2 is applicable, to EN ISO 14555 or

to EN ISO 15620 shall be given. When tests as described in the mentioned standards do not provide

information on the mechanical properties of the joint, and these properties are relevant to the

application, an additional qualification shall be carried out on a butt weld.
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If changes in EN ISO 15614 series appear regarding range of validity and testing, the requirements of the

level should apply, which is comparable the requirements of the latest version of EN ISO 15614 in use in

2018.

For weld performance class CP C3 all standards for the qualification of welding procedure according to

EN ISO 15607 and EN ISO 14555 are permitted.
For fillet welds a separate fillet weld qualification is necessary.

The manufacturer shall have a written procedure detailing how to manage the welding procedure

qualification process.

All WPS shall be verified and authorized for use by the responsible welding coordinator or by the welding

coordinator in charge.
4.1.5 Training and qualification of welders and operators

The manufacturer shall have welders and welding operators with qualification in accordance with series

of standard EN ISO 9606, with EN 287-6, with EN ISO 14555 or with EN ISO 14732. Additionally they

should be trained for tasks, which they do in the workshop.

The manufacturer shall have a list of the valid qualification of its welders and welding operators.

The welders and operators shall follow the instructions of the welding coordinators of the manufacturer.

The manufacturer shall have an adequate number of qualified welders and operators. At least two

welders or operators, who are employees of the manufacturer, for each welding process and welded

material type are recommended.

For the application of EN ISO 9606 (series) in the production of railway vehicles the following rules shall

be considered:
— For fillet welds a separate fillet weld qualification is necessary.

— The FW/BW – test sample according to EN ISO 9606-1:2017, Annex C isn’t accepted.

In addition, welders and operators should be trained about the following issues:
— correct state of the welding equipment;

— availability and compliance of the welding planning documents with the welded component;

— conformity of joint preparations;
— conformity of welding consumables;

— if necessary: cleaning, preheating temperature, inter-pass temperatures, and post weld heat

treatment;
— conformity of the weld relating to the drawing;

— ability to check the weld quality, which is required in accordance with the weld performance class;

— correct tack welding;
— content of 5.2 (see also applicable parts of EN 1011);
— working safety.
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For welding of steel the validity of the qualification of welders shall be in accordance with

EN ISO 9606-1:2017, 9.3 option a or b.

The manufacturer shall have a written procedure detailing how to manage the welder and operator

qualification process.
All welders and operators shall be authorized to weld by a welding coordinator.
4.2 Production weld tests
4.2.1 General
4.2.1.1 Aims and objectives of production weld tests

Due to the complexity of many welded joints in railway vehicles, the responsible welding coordinator

may decide carry out production weld tests to demonstrate that the required quality level can be, or has

been, achieved.
The aims and objectives of (pre-) production weld tests are:

— to check and ensure that the design is suitable as specified in EN 15085-3 (see 4.2.2);

— to prove the welding procedure (see 4.2.3) for welded joints, which are not covered by the usual

welding standards for the welding procedures qualification;

— to demonstrate the skill of the welders (see 4.2.4) for welded joints, which are not covered by the

usual welding standards for the welder qualification;
— to ensure the integrity of the welded joint (see 4.2.5 to 4.2.10).
One production weld test can be used for several tasks indicated above.
4.2.1.2 Realization and amount of testing of production weld test

The production weld tests and the amount of testing shall be specified by the welding coordinator e.g.

during design review or during manufacturing phase.

The production weld test shall be carried out under the same manufacturing conditions as the real

product. They shall be carried out under the supervision of the responsible welding coordinator and they

shall be documented.

The production weld tests may be welded separately as test plates, as sample sub-assemblies (mock-ups)

or together with sub-assembly, for example, as an extension of the weld.

The production weld tests and the amount of testing should be listed in the test plan or specified by the

welding coordinator.

The manufacturer shall have a written procedure detailing how to manage the execution of production

weld tests.
All production weld test results shall be accepted by a welding coordinator.
The results of every production weld test shall be documented.
4.2.2 Production weld tests to check and ensure the design

Test specimens to demonstrate the weldability of the design should be welded as a sample sub-assembly

during the design phase. They are necessary to demonstrate:
— practicability (design which is convenient for welding);
— selection of the material;
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— possibility of testing;
— quality requirements;
— mechanical property data (e.g. strength, ductility).

If no details for the testing of the production weld tests are defined in the test plan, EN ISO 15613 applies.

These production weld test results can be applied to different projects as long as the conditions are the

same; its validity is unlimited in this case.
4.2.3 Production weld tests to prove the welding conditions

For special welds where no proof is possible in accordance with EN ISO 15614, production weld tests are

necessary for proving these welds to ensure the fusion of the weld. The responsible welding coordinator

shall decide which production weld tests are necessary, those can be, for example:

— welds without full penetration on butt and T joints;

— for welds with several degrees of difficulty, e.g. three plate butt welds, plug welds, lap joints,

complicated welds on extrusion profiles;

— to avoid irregularities in production that may be caused by the use of new equipment, jigs, fixtures

or new material;
— HV welds on T joints with single side access.

The production weld tests serve to demonstrate that the specified weld performance class has been

achieved. If no details for the destructive testing of the production weld tests are defined in a test plan,

EN ISO 15613 applies.
4.2.4 Production weld tests to demonstrate the skill of the welder

For welds which require a special skill in welding and are not specified in standards EN ISO 9606-1 or

EN ISO 9606-2 to EN ISO 9606-5, production weld tests are necessary to complete the welders

qualification in relation to the necessary skill required in production. The testing of the production weld

tests shall be carried out as specified in EN ISO 9606-1 to EN ISO 9606-5. If the testing cannot be carried

out according to these standards the responsible welding coordinator should specify the testing.

EN ISO 9606-1 to EN ISO 9606-5 applies to the range of the validity. For the duration of the validity and

the prolongation 4.1.5 applies.

The responsible welding coordinator shall decide about the production weld tests for the qualification of

welders (depending on their specific tasks). It may be necessary for example:
— for HV or HY welds on T joints;

— for welds with several degrees of difficulty, e.g. three plate butt welds, plug welds, cross weld,

complicated welds on extrusion profiles;
— for welds under complicated conditions, e.g. repairing;
— for poor accessibility;
— for welds with backing;
— for materials with poor weldability;
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— for pipe branches and pipe collars;
— for lap joints and corner welds in thin sheets (t ≤ 3 mm);

— for especially high quality requirements, e.g. weld performance class CP A and CP B1 as specified in

EN 15085-3;
— when taking on new welders or welding operators, e.g. staff on loan.

The production weld tests should be listed in the planning documents or specified by the welding

coordinator.
4.2.5 Production weld tests to demonstrate the integrity of the welded joint

The weld quality may be demonstrated with production weld tests, e.g. to ensure the weld quality for

inspection class CT 2 (see EN 15085-5:2007, Table 1), production weld tests are necessary if neither X-

ray nor ultrasonic inspection is possible.
For example, the following conditions should be considered:

— kind of the production weld test and the frequency should be given in the test plan by the welding

coordinator;

— production weld tests shall be taken from the assembly or from an extension of the work piece (e.g.

run-on or run-off plates) or from a similar work piece;

— production weld tests should be checked by a fracture test or macro-section to demonstrate that

their requirements of the demanded weld performance class are fulfilled.
4.2.6 Production weld tests to check electron beam and laser beam welding

Before the start of the fabrication, production weld tests shall be produced and assessed in accordance

with EN ISO 15614-11 (e.g. bending or tensile test). For a change of the design, of the material, in the way

of fabrication or in the production other production weld tests could also be necessary, if the changes can

influence the quality of the weld.

4.2.7 Production weld tests to check resistance spot, roll seam and projection welds

With resistance spot, resistance seam and projection welding, production weld tests shall be produced

according to EN 15085-3:2007, Table F.2. Simplified weld production tests (e.g. bending or tensile shear

test) shall be done before the daily start of the fabrication. Normal weld production tests shall be done to

prove the quality in the production at regular intervals depending on weld volume, weld equipment, and

weld performance class.
4.2.8 Production weld tests to check flash butt welding

For flash butt welds at the beginning of a new production run or when changing the manufacturing

conditions (e.g. materials etc.) it is necessary to demonstrate the quality of the weld by production weld

tests according to EN ISO 15614-13 and testing with a notch bending test, a fracture surface assessment

or a non-destructive testing that the mechanical and technical quality values of the weld are in accordance

with the specification.
4.2.9 Production weld tests to check stud welding

For stud welding, simplified production tests according to EN ISO 14555 shall be done before starting

production or when changing the manufacturing conditions and shall be recorded in a log book.

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4.2.10 Production weld tests to check friction stir welding

For friction stir welding, production weld tests shall be done according to EN ISO 25239-5.

5 Requirements for welding
5.1 General

Listed below are the technical requirements for the welding of railway vehicles and their components. In

addition, the recommendations of series of standards EN 1011 should be observed for welding.

The welding work shall be done in accordance with the relevant welding planning documents.

5.2 General requirements
5.2.1 Weld preparation and other requirements

1) The weld preparation shall be done as specified on the drawing or in other work documents. The

requirements specified in EN 15085-3 should be considered.

2) If there are no specified requirements, the quality of cut edges should be a minimum of class 33

according to EN ISO 9013.

3) The cut surface of sheared cuts or stamped jogs shall be free of notches and cracks. If necessary, these

imperfections shall be ground out.

4) Run-on and run-off plates shall be used according to EN 15085-3:2007, 7.3.11. For thickness

t ≥ 8 mm they shall have the same joint preparation as the actual weld. The run-on and run-off plates

shall be made so as to enable the welding to be started or stopped beyond its necessary length. The

parts to be assembled and the plates, which are “integrated” into the design or implanted as small

plates on the parts to be welded, shall be homogenous. The preparation of these plates shall be the

same as that used on the joints to be made. The plates shall be fixed by mechanical or magnetic means

and can be welded. After having completed the joint, the plates can either be mechanically removed

or cut using a blowpipe or plasma. A longitudinal grinding shall be made after the removal of the

plates. Any rupture caused by shock or breaking is prohibited.

5) All additional weld seams (see 4.1.1), which are not defined in the design documents shall be

accepted and documented by the design department.

6) The surfaces in the weld shall be free from damp and contamination such as dirt, rust, scale, slag, oil,

and paint. For multi-run welding the surface of the previous run shall be prepared so that a

satisfactory welding of the next run is possible. Dirt, slag, and unacceptable imperfections shall be

removed.

7) For corrosion protection on overlap joints and other areas that are no longer accessible after welding,

the application of shop primer paint or coating is acceptable if the following conditions are met:

i) using these primers or coatings is accepted by the customer, if required;
ii) the requirement is included in the design;
iii) the WPQR has been qualified with the primer being applied;
iv) the requirements of EN ISO 17652-1 and EN ISO 17652-2 are met.
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8) The weld joints shall be visible and the accessibility should be optimized for the welder (see 4.2.4).

9) Before welding, any irregularities shall be advised to the welding coordinator, e.g. incorrect weld

preparation, faulty or unsuitable filler metals or unsuitable welding machines.
5.2.2 Execution of the welding

1) Weld layers, weld direction and weld sequence should be chosen so that the welding produces

minimized residual stresses and distortion, so that the weld quality and the required mechanical

properties are achieved.

2) At the end of gussets or stiffeners, the weld return without interruption should be made in

accordance with EN 15085-3.

3) If possible, the welding should be done in position PA or PB. If possible, rotating equipment should

be used.
4) The
...

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