SIST EN ISO 16440:2017
(Main)Petroleum and natural gas industries - Pipeline transportation systems - Design, construction and maintenance of steel cased pipelines (ISO 16440:2016)
Petroleum and natural gas industries - Pipeline transportation systems - Design, construction and maintenance of steel cased pipelines (ISO 16440:2016)
The proposed International Standard will include requirements and guidance for the design, construction and maintenance of steel cased pipes within the oil and natural gas industries.
Erdöl- und Erdgasindustrie - Rohrleitungs-Transportsysteme - Auslegung, Konstruktion und Instandhaltung stahlverkleideter Rohrleitungen (ISO 16440:2016)
Dieses Dokument legt Anforderungen, einschließlich des Korrosionsschutzes, hinsichtlich der Auslegung, Herstellung, Montage und Instandhaltung stahlverkleideter Rohrleitungen bei Rohrleitungstransportsystemen in der petrochemischen und Erdgasindustrie in Übereinstimmung mit ISO 13623 fest.
ANMERKUNG 1 Stahlverkleidungen können für den mechanischen Schutz von Rohrleitungen an Kreuzungen, wie zum Beispiel an Straßen und Bahnwegen, verwendet werden und die zulassende Behörde oder der Betreiber der Rohrleitungen können die Montage einer Verkleidung an einer Fernverkehrsstraße, einem Bahnweg oder einer anderen Kreuzung fordern.
ANMERKUNG 2 Dieses Dokument unterstellt weder eine verpflichtende noch eine notwendige Verwendung von Verkleidungen.
ANMERKUNG 3 Dieses Dokument unterstellt nicht, dass verkleidete Kreuzungen, ob elektrisch getrennt oder elektrisch kurzgeschlossen, zur Korrosion eines Trägerrohrs innerhalb einer verkleideten Kreuzung beitragen. Dennoch können verkleidete Kreuzungen die Intaktheit des Trägerrohrs durch das Abschirmen des Stroms des kathodischen Korrosionsschutzes (KKS) zum Trägerrohr oder durch die Verminderung der Effektivität des kathodischen Korrosionsschutzes im Nahbereich der Verkleidung nachteilig beeinflussen. Die Verwendung einer Verkleidung wird nicht empfohlen, es sein denn, sie ist unter Berücksichtigung von Belastungen, instabilen Bodenverhältnissen oder ihrer Verwendung im Rahmen einer anerkannten Ingenieurspraxis notwendig.
Industries du pétrole et du gaz naturel - Systèmes de transport par conduites - Conception, construction et maintenance de conduites en acier moulé (ISO 16440:2016)
ISO 16440:2016 spécifie les exigences relatives à la protection anti-corrosion, la conception, la fabrication, l'installation et la maintenance des conduites sous fourreau en acier destinées aux systèmes de transport par conduites des industries du pétrole et du gaz naturel conformément à l'ISO 13623.
NOTE 1 Des fourreaux en acier peuvent être utilisés pour protéger les conduites au niveau des traversées, par exemple routes et chemins de fer. L'installation de gaines sur une autoroute, un chemin de fer ou toute autre traversée peut être exigée par l'agence de validation ou l'exploitant de canalisations.
NOTE 2 ISO 16440:2016 n'entend pas prétendre que l'utilisation de gaines est obligatoire ou nécessaire.
NOTE 3 ISO 16440:2016 ne prétend pas que les traversées en gaine, qu'elles soient isolées ou court-circuitées électriquement, favorisent la corrosion d'une conduite de transport avec traversée en gaine. En revanche, les traversées en gaine peuvent affecter l'intégrité de la conduite de transport en faisant écran au courant de la protection cathodique (PC) de la conduite de transport ou en réduisant l'efficacité de la protection cathodique sur la conduite de transport à proximité de la gaine. Leur utilisation n'est pas recommandée sauf si les conditions de charge, l'instabilité du terrain ou les bonnes pratiques d'ingénierie l'exigent.
Industrija nafte in zemeljskega plina - Transportni cevovodni sistemi - Načrtovanje, izvedba in vzdrževanje cevovodov z jekleno oblogo (ISO 16440:2016)
izvedbo in vzdrževanje cevovodov z jekleno oblogo v naftni industriji in industriji zemeljskega plina.
General Information
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN ISO 16440:2017
01-januar-2017
,QGXVWULMDQDIWHLQ]HPHOMVNHJDSOLQD7UDQVSRUWQLFHYRYRGQLVLVWHPL1DþUWRYDQMH
L]YHGEDLQY]GUåHYDQMHFHYRYRGRY]MHNOHQRREORJR ,62
Petroleum and natural gas industries - Pipeline transportation systems - Design,
construction and maintenance of steel cased pipelines (ISO 16440:2016)
Erdöl- und Erdgasindustrie - Rohrleitungs-Transportsysteme - Auslegung, Konstruktion
und Instandhaltung stahlverkleideter Rohrleitungen (ISO 16440:2016)
Industries du pétrole et du gaz naturel - Systèmes de transport par conduites -
Conception, construction et maintenance de conduites en acier moulé (ISO 16440:2016)
Ta slovenski standard je istoveten z: EN ISO 16440:2016
ICS:
75.200 2SUHPD]DVNODGLãþHQMH Petroleum products and
QDIWHQDIWQLKSURL]YRGRYLQ natural gas handling
]HPHOMVNHJDSOLQD equipment
77.140.75 Jeklene cevi in cevni profili Steel pipes and tubes for
za posebne namene specific use
SIST EN ISO 16440:2017 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
---------------------- Page: 1 ----------------------
SIST EN ISO 16440:2017
---------------------- Page: 2 ----------------------
SIST EN ISO 16440:2017
EN ISO 16440
EUROPEAN STANDARD
NORME EUROPÉENNE
November 2016
EUROPÄISCHE NORM
ICS 75.200; 77.140.75
English Version
Petroleum and natural gas industries - Pipeline
transportation systems - Design, construction and
maintenance of steel cased pipelines (ISO 16440:2016)
Industries du pétrole et du gaz naturel - Systèmes de Erdöl- und Erdgasindustrien - Rohrleitungs-
transport par conduites - Conception, construction et Transportsysteme - Auslegung, Konstruktion und
maintenance de conduites en fourreau en acier (ISO Instandhaltung von stahlverkleideten Rohrleitungen
16440:2016) (ISO 16440:2016)
This European Standard was approved by CEN on 7 August 2016.
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, 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: Avenue Marnix 17, B-1000 Brussels
© 2016 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 16440:2016 E
worldwide for CEN national Members.
---------------------- Page: 3 ----------------------
SIST EN ISO 16440:2017
EN ISO 16440:2016 (E)
Contents Page
European foreword . 3
2
---------------------- Page: 4 ----------------------
SIST EN ISO 16440:2017
EN ISO 16440:2016 (E)
European foreword
This document (EN ISO 16440:2016) has been prepared by Technical Committee ISO/TC 67 "Materials,
equipment and offshore structures for petroleum, petrochemical and natural gas industries" in
collaboration with Technical Committee CEN/TC 12 “Materials, equipment and offshore structures for
petroleum, petrochemical and natural gas industries” the secretariat of which is held by NEN.
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 2017, and conflicting national standards shall be
withdrawn at the latest by May 2017.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN [and/or CENELEC] shall 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, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the
United Kingdom.
Endorsement notice
The text of ISO 16440:2016 has been approved by CEN as EN ISO 16440:2016 without any modification.
3
---------------------- Page: 5 ----------------------
SIST EN ISO 16440:2017
---------------------- Page: 6 ----------------------
SIST EN ISO 16440:2017
INTERNATIONAL ISO
STANDARD 16440
First edition
2016-10-15
Petroleum and natural gas
industries — Pipeline transportation
systems — Design, construction and
maintenance of steel cased pipelines
Industries du pétrole et du gaz naturel — Systèmes de transport par
conduites — Conception, construction et maintenance de conduites en
fourreau en acier
Reference number
ISO 16440:2016(E)
©
ISO 2016
---------------------- Page: 7 ----------------------
SIST EN ISO 16440:2017
ISO 16440:2016(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2016, Published in Switzerland
All rights reserved. Unless otherwise specified, 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
Ch. de Blandonnet 8 • CP 401
CH-1214 Vernier, Geneva, Switzerland
Tel. +41 22 749 01 11
Fax +41 22 749 09 47
copyright@iso.org
www.iso.org
ii © ISO 2016 – All rights reserved
---------------------- Page: 8 ----------------------
SIST EN ISO 16440:2017
ISO 16440:2016(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Design . 2
4.1 General . 2
4.2 Carrier pipe design . 3
4.3 Casing design . 3
4.4 Electrical isolation . 4
4.5 Corrosion protection . 4
5 Installation . 4
5.1 General . 4
5.2 Handling and storage. 4
5.3 New casing . 4
5.3.1 General. 4
5.3.2 Carrier pipe installation . 5
5.3.3 Casing end seals . 6
5.3.4 Test leads . 6
5.3.5 Backfilling . 7
5.4 Split-sleeve type casing extensions and installations. 7
6 Inspection and monitoring . 8
6.1 General . 8
6.2 Integrity inspection of carrier pipe . 8
6.3 Monitoring of carrier pipe and casing . 9
6.4 Leakage survey . 9
6.5 Corrosiveness of the annular space . 9
7 Maintenance and repair . 9
7.1 General . 9
7.2 Maintenance of vents and test leads .10
7.3 Clearing of shorted casings .10
7.4 Filling of casings .11
7.5 Removal of casings .11
Annex A (informative) Casing filling procedures for Dielectric Filler Materials .12
Annex B (informative) Examples of cathodic protection testing and monitoring techniques
for carrier pipes and casings .15
Annex C (informative) Inspection tools for cased carrier pipe .30
Annex D (informative) Clearing a shorted casing .35
Annex E (informative) Removing and cutting a casing .37
Bibliography .39
© ISO 2016 – All rights reserved iii
---------------------- Page: 9 ----------------------
SIST EN ISO 16440:2017
ISO 16440:2016(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 on 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 the following URL: www.iso.org/iso/foreword.html.
The committee responsible for this document is ISO/TC 67, Materials, equipment and offshore structures
for petroleum, petrochemical and natural gas industries, Subcommittee SC 2, Pipeline transportation
systems.
iv © ISO 2016 – All rights reserved
---------------------- Page: 10 ----------------------
SIST EN ISO 16440:2017
ISO 16440:2016(E)
Introduction
Users of this document are advised that further or differing requirements might be needed for individual
applications. This document is not intended to inhibit a vendor from offering, or the purchaser from
accepting, alternative equipment, or engineering solutions for the individual application. This might
be particularly applicable where there is innovative or developing technology. Where an alternative is
offered, it is advisable that the vendor identify any variations from this document and provide details.
© ISO 2016 – All rights reserved v
---------------------- Page: 11 ----------------------
SIST EN ISO 16440:2017
---------------------- Page: 12 ----------------------
SIST EN ISO 16440:2017
INTERNATIONAL STANDARD ISO 16440:2016(E)
Petroleum and natural gas industries — Pipeline
transportation systems — Design, construction and
maintenance of steel cased pipelines
1 Scope
This document specifies requirements, including corrosion protection, for the design, fabrication,
installation and maintenance of steel-cased pipelines for pipeline transportation systems in the
petroleum and natural gas industries in accordance with ISO 13623.
NOTE 1 Steel casings can be used for mechanical protection of pipelines at crossings, such as at roads and
railways and the installation of a casing at a highway, railway, or other crossing can be required by the permitting
agency or pipeline operator.
NOTE 2 This document does not imply that utilization of casings is mandatory or necessary.
NOTE 3 This document does not imply that cased crossings, whether electrically isolated or electrically
shorted, contribute to corrosion of a carrier pipe within a cased crossing. However, cased crossings can adversely
affect the integrity of the carrier pipe by shielding cathodic protection (CP) current to the carrier pipe or reducing
the CP effectiveness on the carrier pipe in the vicinity of the casing. Their use is not recommended unless required
by load considerations, unstable soil conditions, or when their use is dictated by sound engineering practices.
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 15589-1, Petroleum, petrochemical and natural gas industries — Cathodic protection of pipeline
systems — Part 1: On-land pipelines
EN 12954, Cathodic protection of buried or immersed metallic structures — General principles and
application for pipelines
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:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1
carrier pipe
pipe that conveys the fluid
Note 1 to entry: Note to entry: This applies to both transmission and distribution piping.
3.2
casing
steel pipe installed around a carrier pipe for mechanical protection
© ISO 2016 – All rights reserved 1
---------------------- Page: 13 ----------------------
SIST EN ISO 16440:2017
ISO 16440:2016(E)
3.3
electrolyte
medium in which electric current is transported by ions
3.4
electrolytic contact
ionic contact between the carrier pipe and the casing pipe through an electrolyte
3.5
end seal
device installed over or within the end of a casing to keep water, deleterious materials and debris out of
the casing or provide a water tight seal between the casing and the carrier pipe
3.6
holiday
unintentional discontinuity in a protective coating that exposes the bare steel surface to the
environment
3.7
isolator
spacer
dielectric device designed to electrically isolate a carrier pipe from a casing and provide support for the
carrier pipe
3.8
metallic short
unintentional contact between two metallic structures
3.9
P/S potential
pipe-to-electrolyte potential
structure-to-electrolyte potential
potential difference between the surface of a buried or submerged metallic structure (pipe or casing)
and the electrolyte that is measured with respect to a reference electrode in contact with the electrolyte
3.10
split sleeve
casing installed in situ by welding two halves of the casing together around the carrier pipe
3.11
tunnel liner plate
steel plate used when micro tunnelling, used to shore horizontal excavations in soft ground
3.12
C/S potential
casing–to–electrolyte potential
potential difference between the surface of a buried or submerged metallic casing and the electrolyte
that is measured with respect to a reference electrode in contact with the electrolyte
4 Design
4.1 General
The purpose of a casing is to provide additional mechanical protection to the carrier pipe. A casing can
also be required by a permitting authority to allow replacement of a carrier pipe without excavations at
the location of a crossing.
2 © ISO 2016 – All rights reserved
---------------------- Page: 14 ----------------------
SIST EN ISO 16440:2017
ISO 16440:2016(E)
A carrier pipe within a casing is not designed to be cathodically protected. It is designed to be electrically
isolated from the casing with non-conducting spacers, or isolated if the annulus of the casing is filled
with a dielectric filler material. The carrier pipe is designed to be protected with a protective coating.
Steel casings shall not be cathodically protected by the pipeline’s dedicated CP system.
4.2 Carrier pipe design
The carrier pipe shall be coated for corrosion protection. The application of an abrasion resistant
coating over the corrosion coating should be considered.
NOTE 1 See NACE/SP 0169 for details of abrasion resistant coatings.
The carrier pipe shall be supported inside the casing with isolating spacers and outside the casing to
prevent sagging. Sagging can lead to metallic contact between the casing and the carrier pipe and to
carrier pipe stresses.
NOTE 2 See NACE/SP 0286 for details of isolation techniques.
4.3 Casing design
Casing design shall be in accordance with the local, national, or industry requirements/standards.
The casing should be kept as short in length as possible to minimize the risk of electrical shorting over
time due to soil stress and pipe movement.
The casing internal diameter shall be selected based on the nominal diameter of the carrier pipe, the
thickness of any abrasion resistant coating, such as concrete, duroplastic material, or epoxy polymer
and the design of the isolators between carrier pipe and casing.
For individual carrier pipes with a nominal diameter of 200 mm (8.0 in) or greater, the outer diameter
of the casing should be a minimum of 100 mm (4.0 in) larger than that of the carrier pipe or if installing
parallel cable or conduits the casing should be a minimum of 300 mm larger than that of the carrier pipe.
For individual carrier pipes with a nominal diameter less than 200 mm (8.0 in), the diameter of the
casing should be a minimum of 50 mm (2.0 in) larger than that of the carrier pipe.
Uncoated casing should be used. Coated or non-conductive casing may be used if the casing can be
harmonized with the carrier pipe cathodic protection.
NOTE 1 The use of coated or nonconductive casing pipe is not recommended due to potential shielding
problems when cathodic protection is applied. If coated casings (either internally coated or externally coated or
both) are used, external cathodic protection will not provide protection to the carrier pipe in the event that the
annulus is filled with a conductive electrolyte.
If vent pipes are required, then they should be installed on both ends of the casing. Vent pipes should be
positioned so that they are not directly over any isolation spacer or end seal. If concrete coated pipe is used
and no isolating spacers are used, then the vent pipes should only be installed on the top of the casing.
The casing vent hole should be at least one-half the diameter of the vent pipe, with a minimum of 25 mm
(1,0 in). The vent pipe should be a minimum of 50 mm (2.0 in) in diameter.
Vent pipes shall be designed to prevent intrusion of water and debris.
Casing end seals shall be installed to prevent ingress of water, deleterious material and debris.
Vent pipes are used for venting, monitoring the casing for carrier pipe leaks, filling the casing and as
line markers.
NOTE 2 NACE/SP 0200 gives guidance for design of end seals.
© ISO 2016 – All rights reserved 3
---------------------- Page: 15 ----------------------
SIST EN ISO 16440:2017
ISO 16440:2016(E)
4.4 Electrical isolation
Sufficient isolators shall be designed to prevent metallic contact between the carrier pipe and the
casing, and to provide adequate support. Isolators shall be designed to minimize coating damage. The
use of metallic components in isolation spacers should be avoided.
Isolators shall be selected to ensure they have the mechanical strength required to withstand the
installation loads, considering all conditions including pipe weight, length of casing, conditions of weld
beads, deflections in the casing and other field conditions. Selection should confirm the ability of the
isolators to provide electrical isolation after installation and to position the carrier pipe properly for
end seal application/installation.
Test leads should be located (connected to the carrier pipe) on the carrier pipe at each end of the casing
to permit verification of metallic isolation. One test lead shall be required as a minimum. Test leads to be
installed in accordance with 5.3.4. Test leads to be installed after the carrier pipe is inserted in the casing.
Metallic shorts between the vent pipe, test leads and carrier pipe shall be prevented.
4.5 Corrosion protection
Consideration may be given to applying cathodic protection to the casing as required by conditions or
regulations. Cathodic protection design shall be in accordance with approved industry standards, such
as ISO 15589-1.
Consideration may be given to placing a high dielectric filler or conductive grout in the annular space or
injecting a vapour phase inhibitor. Annex A gives guidance on filling and the filling procedure.
Cathodically protected casings using the pipelines dedicated CP system may have a detrimental effect
on the carrier pipe.
AC corrosion should be considered as a possible problem when the pipeline is located in an area of AC
influence.
5 Installation
5.1 General
This Clause provides requirements for the installation of new cased pipeline crossings, casing
extensions and new casing installation on existing pipelines.
5.2 Handling and storage
The carrier pipe and casing or tunnel liner plate shall be handled and stored in a manner that minimizes
coating and pipe end damage. Lifting shall be accomplished utilizing slings, wide belts, or appropriate
end hooks. If skids are utilized to support the carrier pipe or casing, padding material shall be used to
prevent coating damage. Skids shall be removed upon completion of the installation.
5.3 New casing
5.3.1 General
Cased crossings are installed using various techniques including boring, directional drilling, tunnelling
and open cutting.
NOTE 1 Filling of the annular space between the casing and excavation is sometimes required by the
permitting agency when the borehole is unstable or fracked out.
4 © ISO 2016 – All rights reserved
---------------------- Page: 16 ----------------------
SIST EN ISO 16440:2017
ISO 16440:2016(E)
Welding of steel casings should be performed in accordance with the pipeline operator’s line pipe
welding specifications.
NOTE 2 ISO 13847 provides guidance on welding.
NOTE 3 Radiographic inspection of casing welds is normally not required.
Butt-weld alignment during casing fabrication shall be maintained to prevent casing, isolator, or spacer
damage during push/pull operations.
Slag and any welding debris shall be removed from inside the casing to prevent damage to the carrier
pipe, coating, isolator, or spacer.
Internal weld beads should be removed by grinding (when practical and allowed) to allow pulling or
sliding of the carrier pipe without damage to the isolators and coating.
The casing vent pipe should be installed before the carrier pipe to avoid coating damage. If the carrier
pipe is already in place when the vent hole is cut, measures shall be taken to prevent coating damage.
NOTE 4 The use of non-flammable insulating material to protect the carrier pipe coating is often required by
the pipeline operator during installation of the vent pipes to prevent coating damage to the carrier pipe.
If two vent pipes are used, the one at the lower elevation should be installed on the bottom of the casing
to facilitate possible filling of the casing at a later date. If the vent pipe is doglegged, adequate separation
and non-metallic suppo
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.