Explosive atmospheres - Part 29-4: Gas detectors - Performance requirements of open path detectors for flammable gases n(IEC 60079-29-4:2009)

This part of IEC 60079-29 specifies performance requirements of equipment for the detection and measuring of flammable gases or vapours in ambient air by measuring the spectral absorption by the gases or vapours over extended optical paths, ranging typically from one metre to a few kilometres. Such equipment measures the integral concentration of the absorbing gas over the optical path in units such as LFL metre for flammable gases.

Explosionsfähige Atmosphäre - Teil 29-4: Gasmessgeräte - Anforderungen an das Betriebsverhalten von Geräten mit offener Messstrecke für die Messung brennbarer Gase (IEC 60079-29-4:2009)

Atmosphères explosives - Partie 29-4: Détecteurs de gaz - Exigences d'aptitude à la fonction des détecteurs de gaz inflammables à chermin ouvert (CEI 60079-29-4:2009)

La CEI 60079-29-4:2009 spécifie les exigences d'aptitude à la fonction des matériels de détection et de mesure des gaz ou vapeurs inflammables dans l'air ambiant dont le principe de fonctionnement est basé sur la mesure de l'absorption spectrale par les gaz ou vapeurs sur des chemins optiques étendus, généralement sur une étendue comprise entre un mètre et quelques kilomètres. Ce type de matériel mesure la concentration intégrale des gaz absorbants sur le chemin optique en unités telles que le LII mètre pour les gaz inflammables. Cette norme complète et modifie les exigences générales de la CEI 60079-0. Lorsqu'une exigence de cette norme entre en conflit avec une exigence de la CEI 60079-0, l'exigence de la présente norme prévaut.

Eksplozivne atmosfere - 29-4. del: Javljalniki plina - Zahteve za delovanje javljalnikov vnetljivih plinov z odprto merilno potjo (IEC 60079-29-4:2009)

Ta del IEC 60079-29 opredeljuje zahteve za delovanje opreme za javljanje in merjenje vnetljivih plinov ali par v zunanjem zraku z merjenjem spektralne absorbcije plinov in par po razširjenih optičnih poteh, ki segajo od enega metra do nekaj kilometrov. Takšna oprema meri celotno koncentracijo absorpcijskega plina po optični poti v enotah, kot je meter LFL (spodnja meja vnetljivosti) za vnetljive pline.

General Information

Status
Published
Publication Date
03-May-2010
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
13-Apr-2010
Due Date
18-Jun-2010
Completion Date
04-May-2010

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SLOVENSKI STANDARD
SIST EN 60079-29-4:2010
01-junij-2010
Eksplozivne atmosfere - 29-4. del: Javljalniki plina - Zahteve za delovanje
javljalnikov vnetljivih plinov z odprto merilno potjo (IEC 60079-29-4:2009)
Explosive atmospheres - Part 29-4: Gas detectors - Performance requirements of open
path detectors for flammable gases n(IEC 60079-29-4:2009)
Explosionsfähige Atmosphäre - Teil 29-4: Gasmessgeräte - Anforderungen an das
Betriebsverhalten von Geräten mit offener Messstrecke für die Messung brennbarer
Gase (IEC 60079-29-4:2009)
Atmosphères explosives - Partie 29-4: Détecteurs de gaz - Exigences d'aptitude à la
fonction des détecteurs de gaz inflammables à chermin ouvert (CEI 60079-29-4:2009)
Ta slovenski standard je istoveten z: EN 60079-29-4:2010
ICS:
29.260.20 (OHNWULþQLDSDUDWL]D Electrical apparatus for
HNVSOR]LYQDR]UDþMD explosive atmospheres
SIST EN 60079-29-4:2010 en,fr
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------

SIST EN 60079-29-4:2010

---------------------- Page: 2 ----------------------

SIST EN 60079-29-4:2010

EUROPEAN STANDARD
EN 60079-29-4

NORME EUROPÉENNE
April 2010
EUROPÄISCHE NORM

ICS 29.260.20 Supersedes EN 50241-1:1999 + A1:2004, EN 50241-2:1999


English version


Explosive atmospheres -
Part 29-4: Gas detectors -
Performance requirements of open path detectors for flammable gases
(IEC 60079-29-4:2009)


Atmosphères explosives -  Explosionsfähige Atmosphäre -
Partie 29-4: Détecteurs de gaz - Teil 29-4: Gasmessgeräte -
Exigences d'aptitude à la fonction Anforderungen an das Betriebsverhalten
des détecteurs de gaz inflammables von Geräten mit offener Messstrecke
à chemin ouvert für die Messung brennbarer Gase
(CEI 60079-29-4:2009) (IEC 60079-29-4:2009)




This European Standard was approved by CENELEC on 2010-04-01. CENELEC 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 Central Secretariat or to any CENELEC 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 CENELEC member into its own language and notified
to the Central Secretariat has the same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus,
the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy,
Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia,
Spain, Sweden, Switzerland and the United Kingdom.

CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung

Central Secretariat: Avenue Marnix 17, B - 1000 Brussels


© 2010 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 60079-29-4:2010 E

---------------------- Page: 3 ----------------------

SIST EN 60079-29-4:2010
EN 60079-29-4:2010 – 2 –
Foreword
The text of document 31/819/FDIS, future edition 1 of IEC 60079-29-4, prepared by IEC Technical
Committee 31, Equipment for explosive atmospheres, was submitted to the IEC-CENELEC parallel vote.
A draft amendment, prepared by the CENELEC SC 31-9, Electrical apparatus for the detection and
measurement of combustible gases to be used in industrial and commercial potentially explosive
atmospheres, of Technical Committee CENELEC TC 31, Electrical apparatus for potentially explosive
atmospheres, was submitted to the formal vote.
The combined texts were approved by CENELEC as EN 60079-29-4 on 2010-04-01.
EN 60079-29-4:2010 supplements and modifies the general requirements of EN 60079-0. Where a
requirement of this standard conflicts with a requirement of EN 60079-0, the requirement of this standard
shall take precedence.
This European Standard supersedes EN 50241-1:1999 + A1:2004 and EN 50241-2:1999.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN and CENELEC shall not be held responsible for identifying any or all such patent
rights.
The following dates were fixed:
– latest date by which the amendment has to be implemented
at national level by publication of an identical
national standard or by endorsement (dop) 2011-01-01
– latest date by which the national standards conflicting
with the amendment have to be withdrawn (dow) 2013-04-01
Annexes ZA, ZZ and ZY have been added by CENELEC.
__________

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SIST EN 60079-29-4:2010
– 3 – EN 60079-29-4:2010
Endorsement notice
The text of the International Standard IEC 60079-29-4:2009 was approved by CENELEC as a European
Standard with agreed common modifications as given below.
In the official version, for Bibliography, the following notes have to be added for the standards indicated:
ISO 6142 NOTE  Harmonized as EN ISO 6142
ISO 6144 NOTE  Harmonized as EN ISO 6144
ISO 6145 NOTE  Harmonized as EN ISO 6145
__________
COMMON MODIFICATIONS
1 Scope

Replace “IEC 60079-29” with “EN 60079-29” in paragraph 1.
Replace “IEC 60079-29-1” with “EN 60079-29-1” in Note 1.
Delete note 3.

2 Normative references

Replace “IEC 60079 (all parts)” with “EN 60079 (all parts)” in paragraph 2.
Replace “IEC 60079-0” with “EN 60079-0” in paragraph 3.
Replace “IEC 60079-29-1” with “EN 60079-29-1” in paragraph 4.

Delete references to IEC 61000-4-1 and IEC 61000-4-3 in paragraphs 6 and 7.

Add the following undated references:

EN 50270, Electromagnetic compatibility - Electrical apparatus for the detection and measurement of
combustible gases, toxic gases or oxygen

EN 50271, Electrical apparatus for the detection and measurement of combustible gases, toxic gases or
oxygen - Requirements and tests for apparatus using software and/or digital technologies

3 Terms and definitions

st
In the 1 paragraph:
Replace “IEC 60079-0” with “EN 60079-0”.
Replace “IEC 60079-29-1” with “EN 60079-29-1”.

4 General requirements

4.1.1

nd
In the 2 paragraph, line 2, replace “… of these other parts of IEC 60079” with “… of the appropriate
regulations for explosion protection”.

4.3

Add “The apparatus shall fulfil the requirements of EN 50271.”
Delete subclauses 4.3.1 to 4.3.5.

---------------------- Page: 5 ----------------------

SIST EN 60079-29-4:2010
EN 60079-29-4:2010 – 4 –
5 Test methods

5.2.4.2
In the second paragraph, replace reference to test 5.4.16 by 5.4.20.

5.4.12
rd
In the 3 paragraph, replace “A 90% of the change.” with “90% of the change.”.

5.4.15 Power supply interruptions and transients
Replace 5.4.15.1, 5.4.15.2 and 5.4.15.3 with “Text deleted”.

5.4.17

Replace this subclause by:

5.4.17 Electromagnetic compatibility
The apparatus shall be set up under normal conditions, in accordance with 5.3, and then shall be
subjected to the tests specified in EN 50270.

NOTE For this test the operating distance may be relaxed to suit the requirements of the EMC test facility.”

7.1 Labelling and marking

Delete the text and replace with:

“The equipment shall comply with the marking requirements of EN 60079-0.

In addition, the equipment shall also be marked:
a) “EN 60079-29-4” (to represent conformance with this performance standard);
b) year of construction (may be encoded within the serial number).”

7.2 Instruction manual

Add “EN” before “60079-0” in paragraph 1, line 2.

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SIST EN 60079-29-4:2010
– 5 – EN 60079-29-4:2010
Annex ZA
(normative)

Normative references to international publications
with their corresponding European publications

The following referenced documents are indispensable for the application 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.

NOTE  When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD
applies.

Publication Year Title EN/HD Year

- - Electromagnetic compatibility - Electrical EN 50270 -
apparatus for the detection and measurement
of combustible gases, toxic gases or oxygen


- - Electrical apparatus for the detection and EN 50271 -
measurement of combustible gases, toxic
gases or oxygen - Requirements and tests
for apparatus using software and/or digital
technologies


IEC 60079 Series Explosive atmospheres EN 60079 Series


IEC 60079-0 - Explosive atmospheres - EN 60079-0 -
Part 0: Equipment - General requirements


IEC 60079-29-1 - Explosive atmospheres - EN 60079-29-1 -
(mod) Part 29-1: Gas detectors - Performance
requirements of detectors for flammable
gases


IEC 60825-1 - Safety of laser products - EN 60825-1 -
Part 1: Equipment classification and
requirements

---------------------- Page: 7 ----------------------

SIST EN 60079-29-4:2010
EN 60079-29-4:2010 – 6 –
Annex ZY
(informative)

Significant changes between this European Standard and EN 50241-1:1999
and EN 50241-2:1999
This European Standard supersedes EN 50241-1:1999 and EN 50241-2:1999.
The significant changes with respect to EN 50241-1:1999 and EN 50241-2:1999 are as listed below.
Type
Minor and Extension Substantial
editorial change
changes regarding
a
ESR´s
Normative references: EN 60068-2-6 (vibration), removed,
X
EN 50271 (software) added
Definitions: 3 modified, 3 added, 2 removed X
General requirements 4.1 and 4.1.1 modified, 4.1.5 replaced
by 4.3 (Software-controlled equipment, new), 4.2.2.4 (low X
battery indications) replaced within 4.2.4 (Fault signals, new)
General requirements and normal conditions for tests
modified and extended (clauses 5.1, 5.2.4.1, 5.2.4.2, 5.3.2, X
5.3.3, 5.3.7, 5.3.8, 5.3.11, 5.3.12)
Test method 5.4.2 (Unpowered storage) modified X
Test method 5.4.3 (Calibration curve) modified
X X
Test method 5.4.4.1, ‘Short term drift’ test removed, replaced
with ‘Slow increase of gas volume ratio’ for equipment with X X
automatic drift compensation
Test method 5.4.4.2 (Long term stability) modified X
Test method 5.4.4.3, Long term stability (continuous duty,
X X
battery powered) test added
Test method 5.4.4.4, Stability (spot reading equipment only)
X X
test added
Test method 5.4.6 (Temperature variation) modified X
Requirements for test 5.4.6 modified X
Test method 5.4.7 removed (Pressure variation) X
Test method 5.4.7 (Water vapour interference) modified X
Requirements for test 5.4.7 modified X
Test method 5.4.8 (Vibration) modified X
Requirements for test 5.4.8 modified X
Test method 5.4.9, Drop test for portable and transportable
X X
equipment added

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SIST EN 60079-29-4:2010
– 7 – EN 60079-29-4:2010
Type
Minor and Extension Substantial
editorial change
changes regarding
a
ESR´s
Test method 5.4.12, Minimum time to operate (spot reading
X X
equipment) test added
Test method 5.4.13 removed (Power supply interruptions etc,
X
now part of EMC requirement of EN 50270)
Test method 5.4.13, Battery capacity test added X X
Test method 5.4.14 (Power supply variations) modified X
Test method 5.4.16 removed (Attenuation of radiation, now
X
part of 5.4.20, Long range operation)
Requirements for test 5.4.16 (now Recovery from power
X
supply interruption) modified
Test method 5.4.19, Partial obscuration test added X X
Requirements for test 5.4.20 (Long range operation) modified X
Labelling and marking requirements modified X
Annex A removed (atmospheric visibility) X
New Annex A added (water vapour test apparatus) X
Bibliography much reduced X
The requirements of EN 50241-2 have been incorporated
into the test methods of the new standard, thus combining X
the two previous standards into one
a
 ESR = Essential Health and Safety Requirements (Annex II of Directive 94/9/EC)

General conclusion on the change of the State of the Art by this standard
CENELEC/TC 31 as the responsible committee has concluded that this new edition contains substantial
changes regarding the ESRs.

---------------------- Page: 9 ----------------------

SIST EN 60079-29-4:2010
EN 60079-29-4:2010 – 8 –
Annex ZZ
(informative)

Coverage of Essential Requirements of EC Directives
This European Standard has been prepared under a mandate given to CENELEC by the European
Commission and the European free Trade Association and within its scope the Standard covers only the
following essential requirements given in Annex II, Clauses 1.5.5 to 1.5.8 of the EC Directive 94/9/EC:
– ER 1.5.5 to 1.5.7 – the essential safety requirements for devices with a measuring function for
explosion protection
– 1.5.5 is covered by 5.4 of this standard
– 1.5.6 is covered by 4.2.1, 4.2.2, and 4.2.4
– 1.5.7 is covered by 4.2.3 and 5.4
– ER 1.5.8 – the risks arising from software
– 1.5.8 is covered by 4.3
Compliance with this standard provides one means of conformity with the specified essential
requirements of the Directive concerned.
WARNING: Other requirements and other EC Directives can be applied to the products falling within the
scope of this standard.

---------------------- Page: 10 ----------------------

SIST EN 60079-29-4:2010

IEC 60079-29-4
®
Edition 1.0 2009-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside


Explosive atmospheres –
Part 29-4: Gas detectors – Performance requirements of open path detectors for
flammable gases

Atmosphères explosives –
Partie 29-4: Détecteurs de gaz – Exigences d’aptitude à la fonction des
détecteurs de gaz inflammables à chemin ouvert

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
V
CODE PRIX
ICS 29.260.20 ISBN 2-8318-1067-6
® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale

---------------------- Page: 11 ----------------------

SIST EN 60079-29-4:2010
– 2 – 60079-29-4 © IEC:2009
CONTENTS
FOREWORD.4
1 Scope.6
2 Normative references .7
3 Terms and definitions .7
3.1 Equipment.7
3.2 Alarms.8
3.3 Signals and indications.8
3.4 Gaseous atmospheres.8
3.5 Optical equipment .9
3.6 Performance characteristics .10
4 General requirements .11
4.1 Detection equipment .11
4.1.1 Components .11
4.1.2 Electrical assemblies and components .11
4.1.3 Optical radiation .11
4.2 Construction.11
4.2.1 General .11
4.2.2 Indicating devices.11
4.2.3 Alarm or output functions.12
4.2.4 Fault signals .12
4.2.5 Adjustments .12
4.3 Software-controlled equipment .12
4.3.1 Conversion errors.13
4.3.2 Software.13
4.3.3 Data transmission.13
4.3.4 Self-test routines .13
4.3.5 Functional concept .14
5 Test requirements .14
5.1 Introduction .14
5.2 General requirements for tests .15
5.2.1 Samples and sequence of tests .15
5.2.2 Constructional checks .15
5.2.3 Preparation of samples.15
5.2.4 Equipment for calibration and test .16
5.3 Normal conditions for test.18
5.3.1 General .18
5.3.2 Operating distance for laboratory tests .18
5.3.3 Test gases.18
5.3.4 Test gas integral concentrations .18
5.3.5 Voltage.19
5.3.6 Ambient temperature .19
5.3.7 Ambient humidity.19
5.3.8 Ambient atmosphere.19
5.3.9 Preparation of equipment .19
5.3.10 Stabilization.19
5.3.11 Communications options.20

---------------------- Page: 12 ----------------------

SIST EN 60079-29-4:2010
60079-29-4 © IEC:2009 – 3 –
5.3.12 Gas detection equipment as part of systems.20
5.4 Test methods .20
5.4.1 Initial preparation and procedure .20
5.4.2 Unpowered storage .20
5.4.3 Calibration curve (not applicable to alarm only equipment with fixed
settings) .20
5.4.4 Stability .21
5.4.5 Alarm reliability.21
5.4.6 Temperature variation .22
5.4.7 Water vapour interference .23
5.4.8 Vibration.23
5.4.9 Drop test for portable and transportable equipment .24
5.4.10 Alignment .24
5.4.11 Time of response.25
5.4.12 Minimum time to operate (spot-reading equipment) .25
5.4.13 Battery capacity.25
5.4.14 Power supply variations (externally powered equipment) .26
5.4.15 Power supply interruptions and transients .27
5.4.16 Recovery from power supply interruption .27
5.4.17 Electromagnetic compatibility (EMC) .27
5.4.18 Beam block fault.28
5.4.19 Partial obscuration.28
5.4.20 Long range operation .29
5.4.21 Direct solar radiation (applicable for equipment intended for outdoor
use).29
6 Field verification equipment.30
7 Information for use .30
7.1 Labelling and marking .30
7.2 Instruction manual.30
Annex A (informative) Water vapour test apparatus .32
Bibliography.33

Figure 1 – Equipment for gas calibration and speed of response test.17
Figure A.1 – Water vapour test apparatus.32

---------------------- Page: 13 ----------------------

SIST EN 60079-29-4:2010
– 4 – 60079-29-4 © IEC:2009
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________

EXPLOSIVE ATMOSPHERES –

Part 29-4: Gas detectors –
Performance requirements of open path
detectors for flammable gases


FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60079-29-4 has been prepared by IEC technical committee 31:
Equipment for explosive atmospheres.
This standard supplements and modifies the general requirements of IEC 60079-0. Where a
requirement of this standard conflicts with a requirement of IEC 60079-0, the requirement of
this standard shall take precedence.
The text of this standard is based on the following documents:
FDIS Report on voting
31/819/FDIS 31/841/RVD

Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.

---------------------- Page: 14 ----------------------

SIST EN 60079-29-4:2010
60079-29-4 © IEC:2009 – 5 –
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts of the IEC 60079 series, under the general title: Explosives atmospheres,
can be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the maintenance result date indicated on the IEC web site under "http://webstore.iec.ch" in
the data related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.

IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates that it contains
colours which are considered to be useful for the correct understanding of its contents. Users
should therefore print this document using a colour printer.

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SIST EN 60079-29-4:2010
– 6 – 60079-29-4 © IEC:2009
EXPLOSIVE ATMOSPHERES –

Part 29-4: Gas detectors –
Performance requirements of open path
detectors for flammable gases



1 Scope
This part of IEC 60079-29 specifies performance requirements of equipment for the detection
and measuring of flammable gases or vapours in ambient air by measuring the spectral
absorption by the gases or vapours over extended optical paths, ranging typically from one
metre to a few kilometres.
Such equipment measures the integral concentration of the absorbing gas over the optical
path in units such as LFL metre for flammable gases.
NOTE 1 Actual values of concentration can be deduced only where it can be established that the concentration is
uniform over the optical path, for example in very short optical paths (<100 mm). In such cases, the equipment is
within the scope of IEC 60079-29-1.
NOTE 2 This sta
...

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