Respiratory protective devices: self-contained open-circuit compressed air breathing apparatus

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Specification for

Respiratory protective

devices:

self-contained

open-circuit

compressed air

breathing apparatus

The European Standard EN 137:1993 has the status of a British Standard

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BS EN 137:1993

This British Standard, having been prepared under the direction of the Personal Safety Equipment Standards Policy Committee, was published under the authority of the Standards Board and comes into effect on

15 April 1993 © BSI 02-1999

First published June 1988 Second edition April 1993 The following BSI references relate to the work on this standard:

Committee reference PSM/14 Draft for comment 90/48400 DC

Cooperating organizations

The European Committee for Standardization (CEN), under whose supervision this European Standard was prepared, comprises the national standards organizations of the following countries.

Austria Oesterreichisches Normungsinstitut

Belgium Institut belge de normalisation

Denmark Dansk Standardiseringsraad

Finland Suomen Standardisoimisliito, r.y.

France Association française de normalisation

Germany Deutsches Institut für Normung e.V.

Greece Hellenic Organization for Standardization

Iceland Technological Institute of Iceland

Ireland National Standards Authority of Ireland

Italy Ente Nazionale Italiano di Unificazione

Luxembourg Inspection du Travail et des Mines Netherlands Nederlands Normalisatie-instituut

Norway Norges Standardiseringsforbund

Portugal Instituto Portuguès da Qualidade

Spain Asociación Española de Normalización y Certificación

Sweden Standardiseringskommissionen i Sverige

Switzerland Association suisse de normalisation United Kingdom British Standards Institution

Amendments issued since publication

Amd. No. Date Comments

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Page

Cooperating organizations Inside front cover

National foreword ii Foreword 2 Introduction 3 1 Scope 3 2 Normative references 3 3 Definitions 3 4 Classification 3 5 Requirements 3 6 Testing 8 7 Marking 15

8 Instructions for use 15

Annex A Recommendations for static and dynamic pressure for

apparatus with thread connector in accordance with EN 148-3 16 Figure 1 — Scheme of a test rig for flammability of a full face mask 10 Figure 2 — Arrangement of the six propane burners i.e. with lung

governed demand valve 12

Figure 3 — Scheme of harness material single burner flame test 13

Figure 4 — Scheme of safety valve test 14

Figure A.1 — Scheme of a test rig for dynamic pressure 17

Table 1 — Untitled 6

National annex NA (informative) Committees responsible Inside back cover National annex NB (informative) Cross-references Inside back cover

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BS EN 137:1993

National foreword

This British Standard has been prepared under the direction of the Personal Safety Equipment Standards Policy Committee and is the English language version of EN 137 “Respiratory protective devices — Self-contained open-circuit

compressed air breathing apparatus — Requirements, testing, marking”,

published by the European Committee for Standardization (CEN). It supersedes BS 7004:1988 which is withdrawn.

EN 137 was produced as a result of international discussions in which the United Kingdom took an active part.

A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application.

Compliance with a British Standard does not of itself confer immunity from legal obligations.

Summary of pages

This document comprises a front cover, an inside front cover, pages i and ii, the EN title page, pages 2 to 18, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on

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UDC 614.894-72:620.1:62-777 Supersedes EN 137:1986 Descriptors: Accident prevention, personal protective equipment, respiratory protective equipment, compressed air, specifications,

tests, marking

English version

Respiratory protective devices —

Self-contained open-circuit compressed air

breathing apparatus — Requirements, testing, marking

Appareils de protection respiratoire —

Appareils de protection respiratoire autonomes

à circuit ouvert, à air comprimé — Exigences,

essais, marquage

Atemschutzgeräte — Behältergeräte mit

Druckluft (Preßluftatmer) — Anforderungen,

Prüfung, Kennzeichnung

This European Standard was approved by CEN on 1993-01-18. 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 Central Secretariat 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 Central Secretariat has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom.

CEN

European Committee for Standardization Comité Européen de Normalisation Europäisches Komitee für Normung

Central Secretariat: rue de Stassart 36, B-1050 Brussels

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EN 137:1993

Foreword

This European Standard was prepared by the Technical Committee CEN/TC 79 “Respiratory protective devices”, of which the secretariat is held by DIN.

This European Standard has been prepared under a mandate given to CEN by the Commission of the European Communities and the European Free Trade Association, and supports essential requirements of the EC Directive(s).

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 1993, and conflicting national standards shall be withdrawn at the latest by July 1993.

The Standard was approved and in accordance with the CEN/CENELEC Internal Regulations, the following countries are bound to implement this European Standard: Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland,

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Introduction

A given respiratory protective device can only be approved when the individual components satisfy the requirements of the test specification which may be a complete standard or part of a standard, and practical performance tests have been carried out on complete apparatus where specified in the

appropriate standard. If for any reason a complete apparatus is not tested then simulation of the apparatus is permitted provided the respiratory characteristics and weight distribution are similar to those of the complete apparatus.

1 Scope

This European Standard refers to self-contained open-circuit compressed air breathing apparatus used as respiratory protective devices, except escape apparatus and diving apparatus. It specifies the minimum requirements for self-contained open-circuit compressed air breathing apparatus. Laboratory and practical performance tests are included for the assessment of compliance with the requirements.

2 Normative references

This European Standard incorporates by dated or undated reference, provisions from other

publications. These normative references are cited at the appropriate places in the text and the publications are listed hereafter. For dated

references, subsequent amendments to or revisions of any of these publications apply to this

European Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies. EN 132, Respiratory protective devices; Definitions. EN 134, Respiratory protective devices;

Nomenclature of components.

EN 136, Respiratory protective devices; Full face

masks; Requirements, testing, marking.

EN 136-10, Respiratory protective devices; Full face

masks for special use; Requirements, testing, marking.

EN 142, Respiratory protective devices; Mouthpiece

assemblies; Requirements, testing, marking.

EN 148-1, Respiratory protective devices; Threads

for facepieces; Standard thread connection.

for facepieces; Centre thread connection.

for facepieces; Thread connection M 45 × 3.

3 Definitions and description

For the purposes of this European Standard the definitions given in EN 132 and the nomenclature of the components given in EN 134 apply together with the following.

A self-contained open-circuit compressed air breathing apparatus is an apparatus which has a portable supply of compressed air and is

independent of the ambient atmosphere.

Abbreviation: compressed air breathing apparatus: CABA.

Compressed air breathing apparatus are designed and constructed to enable the wearer to breathe air on demand from a high pressure air cylinder (or cylinders) either via a pressure reducer and a lung governed demand valve or a lung governed demand valve connected to the facepiece. The exhaled air passes without recirculation from the facepiece via the exhalation valve to the ambient atmosphere.

4 Classification

Compressed air breathing apparatus are classified according to the following effective air volumes at a pressure of 1 bar absolute and a temperature of 20 °C: — at least 500 l — at least 600 l — at least 800 l — at least 1 200 l — at least 1 600 l — at least 2 000 l

5 Requirements

5.1 Design

The apparatus shall be of simple and reliable construction and as compact as possible. The design of the apparatus shall be such as to allow its reliable inspection.

The apparatus shall be sufficiently robust to withstand the rough usage it is likely to receive in service.

The apparatus shall be designed so that there are no protruding parts likely to be caught on projections in narrow passages.

The finish of any part of the apparatus likely to be in contact with the wearer shall be free from sharp edges or burrs.

The apparatus shall be designed so that the wearer can remove it and, while still wearing the facepiece, continue to breathe from the apparatus.

The apparatus shall be designed to ensure its full function in any orientation.

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BS EN 137:1993

The main valve(s) of air cylinder(s) shall be arranged so that the wearer can operate it (them) while wearing the apparatus.

If apparatus (of the same class) are designed for use with different sizes of cylinders changing of

cylinders shall be possible without the use of special tools.

Testing in accordance with 6.1 and 6.2. The apparatus shall continue to function

satisfactorily after being submerged in water to a maximum depth of 1 m.

Testing in accordance with 6.1.

WARNING. The apparatus is not designed for use under water.

5.2 Materials

All materials used shall have adequate mechanical strength, durability and resistance to deterioration. The materials used shall be anti-static as far as it is practicable.

Exposed parts i.e. those which may be subjected to impact during use of the apparatus shall not be made of aluminium, magnesium, titanium or alloys containing such proportions of these metals as will, on impact, give rise to frictional sparks capable of igniting flammable gas mixtures.

Any cylinder making use of such materials shall be adequately protected. If national regulations allow the use of such cylinders, then, when tested for impact and scraping no metal shall be exposed. Material that may come into contact with the wearer’s skin shall not be known to be likely to cause irritation or any other adverse effect to health.

Testing in accordance with 6.1 and 6.2.

5.3 Cleaning and disinfecting

The materials used shall withstand the cleaning and disinfecting agents and procedure

recommended by the manufacturer. Testing in accordance with 6.1.

5.4 Mass

The mass of the apparatus as ready for use with facepiece and fully charged compressed air cylinder(s) shall not exceed 18 kg.

5.5 Connections (couplings)

The design and construction of the apparatus shall permit its components to be readily separated for cleaning, inspecting and testing. Demountable connections to achieve this shall be readily connected and secured, preferably by hand.

Any means for sealing used shall be retained in position when the connection(s) is (are)

disconnected during normal maintenance. Testing in accordance with 6.1 and 6.2.

5.6 Facepiece connector

The connection between the breathing apparatus and the facepiece may be achieved by a permanent, special or thread type connector.

A thread connector shall comply with the requirements of one of the following standards.

— EN 148-1 for breathing apparatus without positive pressure

— EN 148-2 for closed-circuit breathing apparatus

— EN 148-3 for breathing apparatus with positive pressure.

If any other thread type connector is used it shall not be possible to connect it to the above mentioned threads.

The standard thread according to EN 148-1 shall not be used for apparatus with positive pressure, closed-circuit apparatus and diving apparatus. The thread according to EN 148-2 shall not be used for open-circuit devices and diving apparatus. The thread according to EN 148-3 shall not be used for apparatus without positive pressure,

closed-circuit apparatus and diving apparatus. Testing in accordance with 6.1.

If a thread connector in accordance with EN 148-3 is used then the requirements of Annex A should be met, when tested in accordance with Annex A.

5.7 Body harness

The body harness shall be designed to allow the user to don and doff the apparatus quickly and easily without assistance and shall be adjustable. All adjusting devices shall be so constructed that once adjusted they will not slip inadvertently.

The body harness shall be constructed such that when tested in practical performance tests the apparatus shall be worn without avoidable

discomfort, the wearer shall show no undue sign of strain attributable to wearing the apparatus, and that the apparatus shall impede the wearer as little as possible when in a crouched position or when working in a confined space.

The material of the straps and of the buckles shall be considered to be flame resistant if it does not burn or if it does not continue to burn after 5 s after removal from the test flame.

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The harness shall be considered satisfactory if during the practical performance test it does not slip and continues to hold the apparatus securely to the wearer’s body throughout the duration of the test. Testing in accordance with 6.3.1.4.

5.8 Practical performance tests

In addition to the machine tests described the apparatus shall also undergo practical performance tests under realistic conditions. These general practical performance tests serve the purpose to check the apparatus for imperfections that cannot be determined by the tests described elsewhere in this European Standard.

Where in the opinion of the testing authority approval is not granted because practical performance tests show the apparatus has imperfections related to wearer’s acceptance the testing authority shall describe the tests which revealed these imperfections. This will enable other testing stations to duplicate the tests and assess the results thereof.

Testing in accordance with 6.2 and 6.3.2.

5.9 Resistance to temperature and flammability

5.9.1 Storage

After conditioning and return to (20 ± 3) °C the connectors between apparatus and facepiece shall be examined.

For standardized threads a thread gauge shall be used to check dimensions.

For all equipment connectors a pull test as described in clauses 4.12.3 and 5.7 of EN 136 shall be applied and no separation shall occur.

After the test the equipment connector shall be dimensionally correct.

Testing in accordance with 6.3.1.5.

5.9.2 Temperature-performance

The apparatus shall operate trouble-free over the temperature range of – 30 °C to 60 °C.

Apparatus specifically designed for temperatures beyond these limits shall be tested and marked accordingly.

5.9.2.1 Low temperature

For breathing apparatus without positive pressure the inhalation resistance shall not exceed 10 mbar. For breathing apparatus with positive pressure a positive pressure shall be maintained in the cavity of the mask adjacent to the face seal.

The exhalation resistance of all types of apparatus shall not exceed 10 mbar.

Testing in accordance with 6.3.1.1.

5.9.2.2 Breathing resistance at high temperature 5.9.2.2.1 Apparatus without positive pressure

For breathing apparatus without positive pressure the inhalation resistance shall not exceed 7 mbar. The exhalation resistance shall not exceed 3 mbar. Testing in accordance with 6.3.1.2.1.

5.9.2.2.2 Apparatus with positive pressure

For breathing apparatus with positive pressure a positive pressure shall be maintained in the cavity of the mask adjacent to the face seal.

The exhalation resistance shall not exceed 10 mbar. Testing in accordance with 6.3.1.2.2.

5.9.3 Flammability

When tested in accordance with 6.3.1.3 the breathing tube(s) (leading to facepiece), medium pressure tube(s) and lung governed demand valve shall prove to be “self-extinguishing”, i.e. the material shall not be of highly flammable nature and when tested in accordance with 6.3.1.3 the parts shall not continue to burn for more than 5 s after removal from the flame.

The components are considered to be resistant to flammability in accordance with this standard if they remain leaktight after the test although they may be deformed.

5.9.4 Resistance to radiant heat

The breathing tube(s) (leading to facepiece), medium pressure tube(s) and lung governed demand valve shall be tested for resistance to radiant heat.

The components are considered to be resistant to radiant heat in accordance with this standard if they remain leaktight after a test period of 20 min although they may be deformed.

Testing in accordance with EN 136-10.

5.10 Protection against particulate matter

The piece parts of the apparatus supplying compressed air shall be reliably protected against the penetration of particulate matter that may be contained in the compressed air.

5.11 High pressure parts

Metallic high pressure tubes, valves and couplings shall be tested to prove that they are capable of withstanding a pressure of 50 % above the maximum filling pressure of the compressed air cylinder.

Non-metallic parts shall be tested to prove that they are capable of withstanding a pressure of twice the maximum filling pressure of the compressed air cylinder.

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BS EN 137:1993

5.12 High and low pressure connections

It shall not be possible to fit a low pressure tube or hose directly to a high pressure part of the circuit. Testing in accordance with 6.1.

5.13 Air cylinders

The air cylinder shall comply with appropriate national regulations. The cylinder shall be approved with respect to the appropriate filling pressure. Where cylinders are reused cylinder neck threads may be of the old national design.

5.14 Cylinder valves

The design of the cylinder valve shall be such as to ensure safe performance.

The cylinder valve shall be protected against blockage and transmission of particulate matter that may be contained in the compressed air. The valve shall be so designed that the valve spindle cannot be completely unscrewed from the assembly during normal operation of valve.

The valve shall be designed or so located that it cannot be closed inadvertently.

This is met e.g. by at least 2 turns from fully open to fully closed position.

Apparatus fitted with more than one cylinder may be fitted with individual valves on each cylinder. It shall not be possible to fit two or more cylinders of different filling pressures to the same apparatus. Testing in accordance with 6.1.

5.15 Compressed air cylinder valve outlet

The compressed air cylinder valve outlet shall comply with EN 144-2.

5.16 Pressure reducer

If the apparatus is designed with a pressure reducer, any adjustable medium pressure stage shall be reliably secured against accidental alteration and adequately sealed so that any unauthorized adjustment can be detected. Testing in accordance with 6.1.

5.16.1 Apparatus with a pressure reducer safety valve

A pressure reducer safety valve shall be provided if the down stream parts of the apparatus cannot take full cylinder pressure.

The pressure reducer safety valve shall be designed to pass an air flow of 400 l/min at a medium pressure not exceeding 30 bar.

With the pressure reducer safety valve activated, the inhalation and exhalation breathing resistance shall not exceed 25 mbar.

5.16.2 Apparatus without a pressure safety valve

Where a pressure reducer safety valve is not provided, the breathing resistance requirements of 5.16.1 shall be met.

5.17 Pressure gauge

The apparatus shall be equipped with a reliable pressure gauge which will read the pressure in the cylinder(s) on opening the valve(s) to ensure that the individual or the equilibrated pressure is measured respectively.

The pressure gauge shall be positioned to enable the pressure to be read conveniently by the wearer.

NOTE National regulations for use may permit the pressure gauge to be located on the back.

The pressure gauge tube shall be sufficiently robust to withstand rough usage. Where the tube is protected by a cover the enclosed space shall be vented to the atmosphere.

The pressure gauge shall be resistant to water and shall withstand immersion in water at a depth of 1 m for 24 h. After the test, no water shall be visible in the device.

The pressure gauge shall be graduated from the zero mark up to a value of at least 50 bar above the maximum filling pressure of the cylinder.

The accuracy of the reading when tested at decreasing pressure shall have the following tolerances when compared with a test gauge:

Table 1

It shall be possible to read the gauge marking (as given in Table 1 in poor light.

The design of the gauge shall enable the wearer to estimate the pressure to within 10 bar.

When pressure gauge and connecting hose are removed from the apparatus, then the flow shall not exceed 25 l/min at 200 bar.

Pressure Tolerance 300 bar 200 bar 100 bar 40 bar ± 10 bar ± 10 bar ± 10 bar + 0 bar – 5 bar

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5.17.1 Pressure gauge of the pointer type

The pressure gauge shall be provided with a blow out release which protects the wearer against injuries.

The gauge window shall be made of a material being non-splintering when breaking.

5.17.2 Pressure gauge of the Braille type

The sliding indicator pin shall be secured against accidental blow out.

5.18 Warning device

The apparatus shall have a suitable warning device that operates when the cylinder pressure drops to a pre-determined level to warn the wearer.

The warning device shall either be activated automatically when the cylinder valve(s) is (are) opened, or if manually activated it shall not be possible to use the apparatus before the device is activated.

The warning device shall respond at a pressure of (55 ± 5) bar or when at least 200 l of air remain within the cylinder. Warning devices may be fitted with other pressure settings than 55 bar or at an air capacity in excess of 200 l when special user requirements exist. After response of the warning device, the wearer shall be able to continue breathing without difficulty.

5.18.1 Audible warning device

If there is an audible warning device the sound pressure level shall be at least 90 dB (A) measured at the ear nearest to the device.

The signal may be continuous or intermittent. At the predetermined operating pressure of the warning device ± 5 bar the duration of the warning at 90 dB (A) shall be at least 15 s for a continuous signal, and 60 s for an intermittent signal and thereafter shall continue to sound down to 10 bar. The frequency range shall be between 2 000 Hz and 4 000 Hz.

The air loss that might be caused by the warning signal shall not exceed an average of 5 l/min from response of signal to a pressure of 10 bar or not exceed a total of 85 l.

The warning device shall continue to operate in a temperature range of 0 °C to 10 °C at a relative humidity of 90 %.

5.19 Flexible hoses and tubes 5.19.1 Breathing hose

Breathing hoses shall be flexible and non-kinking. The breathing hoses shall permit free head movement and shall not restrict or close off the supply under chin or arm pressure during practical performance tests.

The hose shall not collapse. Testing in accordance with 6.2.

5.19.2 Medium pressure connecting tube

Tubes to the demand valve (connections included) shall withstand, for 15 min, twice the operating pressure of the pressure reducer safety valve or at least 30 bar whichever is the higher.

5.20 Lung governed demand valve

Testing in accordance with 6.1, 6.6 and 6.7.

5.20.1 Breathable air supply

The breathable air supply shall be sufficient for a sinusoidal flow of 40 × 2.5 l/min at all cylinder pressures above 20 bar and of 25 × 2 l/min at a cylinder pressure of 10 bar.

5.20.2 Without positive pressure

The negative pressure for opening the lung governed demand valve shall be between 0,5 and 3,5 mbar when tested using a continuous flow of 10 l/min, from maximum filling pressure to 10 bar.

A self-opening of the demand valve at negative pressures of less than 0,5 mbar shall not occur. At a sinusoidal flow of 40 × 2,5 l/min the negative pressure shall not exceed 10 m/bar at all pressures from maximum filling pressure to 20 bar.

5.20.3 With positive pressure

The lung governed demand valve for positive pressure apparatus shall be fitted with a manual or an automatic change-over switch.

5.20.4 Supplementary air supply

Apparatus without positive pressure shall be provided with a manually operated means of providing a supply of air at a flow rate of at

least 60 l/min at all cylinder pressures above 50 bar. Apparatus with positive pressure may be provided with such a device.

5.20.5 Leaktightness

The assembled apparatus shall be so designed and constructed as to prevent ingress of the external atmosphere as well as to prevent a substantial reduction of the effective duration.

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BS EN 137:1993

5.20.5.1 Without positive pressure

The assembled apparatus without facepiece shall be tested for leaktightness at a negative and a positive pressure of 7,5 mbar. After the pressure has stabilized the pressure change shall not be greater than 0,3 mbar in 1 min.

Testing in accordance with 6.7.1.

When tested in accordance with 6.7.2 the pressure change shall not be greater than 10 bar in 1 min.

5.20.5.2 With positive pressure

When tested in accordance with 6.7.2 the pressure change shall not exceed 20 bar in 1 min.

5.21 Adjustable parts

All parts requiring manipulation by the wearer shall be readily accessible and easily

distinguishable from one another by touch. All adjustable parts and controls shall be constructed so that their adjustment is not liable to accidental alteration during use.

5.22 Facepiece

Only a full face mask in accordance with EN 136 or a mouthpiece assembly in accordance with EN 142 shall be used.

5.23 Breathing resistance

5.23.1 Inhalation resistance

At a sinusoidal flow of 25 × 2 l/min the inhalation resistance of an apparatus without facepiece shall not exceed 4,5 mbar at all cylinder pressures from maximum filling pressure to 10 bar.

Where a lung governed demand valve is attached to a full face mask the negative pressure shall not exceed 7 mbar.

The apparatus shall be designed such that positive pressure is maintained in the cavity of the mask adjacent to the face seal. The pressure shall be positive but not exceed 5 mbar.

At a sinusoidal flow of 40 × 2,5 l/min this

requirement shall be met at all cylinder pressures above 20 bar and at a sinusoidal flow of 25 × 2 l/min the requirement shall be met down to a cylinder pressure of 10 bar.

If the apparatus is equipped with a thread connector in accordance with EN 148-3 then the test rig described in Annex A.2 should be used.

5.23.2 Exhalation resistance

This requirement applies only to apparatus with incorporated facepiece.

The exhalation resistance shall not exceed 3,0 mbar.

The exhalation valve shall have an opening resistance not exceeding 6 mbar at a continuous flow of 10 l/min and a resistance not

exceeding 7 mbar at a sinusoidal flow of 25 × 2 l/min and a resistance not exceeding 10 mbar at a sinusoidal flow of 40 × 2,5 l/min.

5.24 Static pressure

The static pressure in the mask cavity under conditions of equilibrium shall not exceed 5 mbar.

6 Testing

If no special measuring devices or measuring methods are specified, commonly used methods and devices should be applied.

Positive pressure apparatus shall be tested as complete apparatus including the facepiece as supplied by the applicant.

6.1 Visual inspection

The visual inspection shall be carried out where appropriate by the test station prior to laboratory or practical performance tests. The visual inspection shall include marking and instructions for use.

6.2 Practical performance tests

Practical performance tests shall be performed with two apparatus and four test subjects.

6.2.1 Test subjects

The apparatus shall be tested by test subjects practising regularly with breathing apparatus and their medical history shall be known to be

satisfactorily. They shall be medically examined and certified fit to undertake the test procedures. The necessity of a medical examination immediately before tests and a medical supervision during the tests shall be decided by the testing authority.

6.2.2 Apparatus to be tested

For practical performance tests only apparatus which has passed the laboratory tests shall be used.

6.2.3 Preparation of apparatus to be tested

Before starting each test the apparatus shall be checked for leak tightness and opening pressure of the demand valve. The cylinder pressure at the start of the test shall correspond to the prescribed filling pressure.

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6.2.4 Test procedure

All tests shall be carried out at room temperature and the test temperature and humidity shall be recorded.

During the test the apparatus shall be subjectively assessed by the wearer and the wearers’ comments and the following details shall be recorded after the test:

a) harness comfort

b) security of fastenings and couplings c) accessibility of controls and pressure gauge d) clarity of vision of the visor of the facepiece (if applicable)

e) supplementary supply (if fitted) f) speech transmission

g) warning device

h) any other comment reported by the wearer on request.

6.2.4.1 Walking test

Two subjects in normal working clothes wearing the apparatus shall walk at a regular rate of 6 km/h on a level course. The test shall be continuous, without removal of the apparatus, for a period equal to the working duration of the apparatus or 30 min, whichever is less.

NOTE If the warning device has not operated during the 30 min test period, the cylinder pressure shall be reduced manually to the warning pressure range to check the effectiveness of the latter, which shall conform with the requirements of 5.18.

6.2.4.2 Work simulation test

The apparatus shall be tested under conditions which can be expected during normal use. During this test the following activities shall be done in simulation of the practical use of the apparatus. The test shall be completed within a total working time of 30 min.

The sequence of activities is at the discretion of the test authority. The individual activities shall be arranged so that sufficient time is left for the measurements prescribed.

a) Thirty strokes on a work machine, each stroke being vertical from 1,8 m towards the ground on a mass of 25 kg, giving a total work load

of 13 500 N·m.

b) Walking on the level with full headroom (total distance 125 m)1).

c) Walking on the level with headroom of (1,3 ± 0,2) m (total distance 200 m)1). d) Crawling on the level with headroom of (0,70 ± 0,05) m (total distance 100 m)1).

e) Climbing up and down a ladder, passing once, in each direction through a 460 mm square opening (total vertical distance 20 m)1).

f) Crawling through a narrow section (4 m long) which is so low that the test subject has to doff the apparatus and push it in front of him or pull it behind him while still breathing from the apparatus.

g) Laying out of a firehose of at least 15 m in length and recoiling the same.

This test shall be continuous, without removal of the apparatus, for an initial period of

approximately 15 min, after which the subject shall have a rest period of 5 min during which he can be medically assessed and allows for time to change the compressed air cylinder if the testing officer considers that there may be insufficient air to complete the test.

The second section of the test shall then continue to complete a working time of 30 min. If the exercises have been completed within less than 30 min, the remaining time is used by the subject to walk at 6 km/h.

6.3 Resistance to temperature and flammability

6.3.1 Laboratory tests with a breathing machine

6.3.1.1 Tests at low temperature

The apparatus including the compressed air cylinder(s) and facepiece according to EN 136 or EN 142 shall be cooled in an ambient temperature of (– 30 ± 3) °C for at least 4 h.

In the case of wrapped composite cylinders the time shall be at least 12 h.

Subsequently the apparatus shall be connected to a breathing machine placed outside the cooling system. The breathing machine shall then be operated at a minute volume

of 50 l (25 cycles/min, 2 l/stroke) until the compressed air supply is exhausted (20 bar). The test shall be repeated with the same cooled apparatus, after having replaced the empty

cylinder(s) by a) fully charged cylinder(s) previously stored at room temperature.

6.3.1.2 Tests at high temperature

The apparatus including compressed air cylinder(s) (filling pressure: 100 bar) and a facepiece according to EN 136 or EN 142 is stored in a chamber at a temperature of (60 ± 3) °C and a relative humidity of not more than 50 % for 4 h.

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BS EN 137:1993

6.3.1.2.1 Apparatus without positive pressure

The apparatus shall be tested using a breathing machine operating at 25 cycles/min, 2 l/stroke until the compressed air supply is exhausted (20 bar).

6.3.1.2.2 Apparatus with positive pressure

The apparatus shall be tested using a breathing machine operating at 40 cycles/min, 2,5 l/stroke until the compressed air supply is

exhausted (20 bar).

6.3.1.3 Flammability

The specimen shall be tested for flammability for a short period with a test rig as shown in Figure 1 and Figure 2. This test rig consists mainly of a propane cylinder with flow control device and pressure gauge, flash back arrester, six propane burners being adjustable in height.

The test rig shall be adjusted as follows:

The distance between specimen and burner tips shall be 250 mm.

Fully open the propane control valve on each of the six burners. Initially close the air control valve on each of the six burners. Adjust the propane cylinder output regulator to a pressure2) such that a

flowmeter in the main propane supply line indicates a total flow to all six burners of (21 ± 0,5) l/min propane.

The temperature of the flame at a height of 250 mm above the burner tips and in the centre of the triangle formed by the burners, shall

be (950 ± 50) °C.

In order to achieve the correct temperature, it may be necessary to adjust the air control valve on each burner to an optimum and to shield the whole test apparatus from the effect of external air flows. The specimen shall be exposed to the flames for a period of 5 s.

6.3.1.4 Flammability of body harness

The harness material shall be tested by placing the material in a luminous propane gas flame. The air valve on the burner shall be fully closed. The flame height shall be adjusted to 40 mm by regulating the gas supply and the flame shall have a temperature of (800 ± 50) °C measured at a height of 20 mm above the base of the flame. The material under test shall be held horizontally at a height of 20 mm above the base of the flame for a period of 12 s such that the flame impinges on the edge of the

component under test with a test rig as shown in Figure 3.

2) _Note

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6.3.1.5 Temperature conditioning

One apparatus shall be exposed to the following thermal cycle:

a) for 72 h to a dry atmosphere of (70 ± 3) °C b) for 72 h to an atmosphere of (70 ± 3) °C at 95 – 100 % relative humidity

c) for 24 h to a temperature of (– 30 ± 3) °C WARNING. The cylinders shall be charged to not more than 50 % of filling pressure during

conditioning.

6.3.2 Practical performance tests

6.3.2.1 Test at low temperature

6.3.2.1.1 Preparation of apparatus to be tested

Two sets of apparatus, as ready for use, shall be cooled at a temperature of (– 30 ± 3) °C for a period of 4 h.

6.3.2.1.2 Test procedure

Two warmly clothed subjects shall don the cooled apparatus in a cold chamber and perform work at an ambient temperature of (– 15 ± 3) °C. The test shall be continuous without removal of the apparatus over a period of 30 min or at least until the warning device starts to operate.

The work shall be equally divided between: a) walking and crawling slowly

b) carrying and building with wooden blocks or similar.

At the end of the test, the resistance to breathing shall be measured to determine whether there is any obstruction, and the apparatus shall be examined for malfunction due to the low temperature.

6.3.2.2 Test at low temperature after storage at room

temperature

6.3.2.2.1 Preparation of apparatus to be tested

Two sets of apparatus as ready for use shall be stored at room temperature (23 ± 2) °C for at least 4 h.

6.3.2.2.2 Test procedure

Two warmly clothed subjects shall don the apparatus at room temperature (about 23 °C) and enter a cold chamber of (– 6 ± 2) °C. The same test programme as that described in 6.3.2.1.2 shall be carried out for a period of 30 min or at least until the warning device starts to operate.

The apparatus including facepiece is connected to a breathing machine by a suitable connector;

apparatus with a full face mask shall be fitted to the “Sheffield” dummy head and apparatus with a mouthpiece shall be connected directly to the outlet of the breathing machine. The breathing machine is adjusted to 25 cycles/min and 2 l/stroke

(see Figure 4).

6.4.1 Apparatus with a pressure reducer safety valve

With the breathing machine not operating, a suitable flow measuring device is connected to the outlet of the safety valve and air is supplied to the medium pressure side of the pressure reducer. The air supply pressure is gradually increased until a flow of 400 l/min passes through the safety valve. Whilst under these conditions, the breathing machine is started and the breathing resistance is measured at the appropriate pressure sample point.

6.4.2 Apparatus without a pressure reducer safety valve

The outlet of the demand valve is connected to a suitable flow measuring device. Air is supplied to the medium pressure side of the pressure reducer and the air supply pressure is gradually increased. The medium pressure required to create a

continuous flow of 400 l/min through the safety valve is recorded.

Under these conditions, a breathing machine test is conducted on the complete apparatus including the facepiece and the breathing resistance is measured at the appropriate pressure sample point.

6.5 Warning device

The performance of the warning device is measured during a breathing machine test

at 25 cycles/min × 2 l/stroke.

To test the warning device at temperatures

between 0 °C and 10 °C, air shall be passed through the apparatus in a climatic test chamber using a breathing machine (adjusted

to 25 cycles/min × 2 l/stroke).

During the test, the environment of the apparatus shall have a temperature of ( °C and a relative humidity of > 90 %.

Every 5 min, water shall be sprayed on for 3 s using a spray gun3) directed at the warning device from a distance of 200 mm.

The test shall be repeated immediately after this.

3) _{Information may be obtained from the secretariat of CEN/TC 79.}

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6.6 Breathing resistance

The breathing resistance of the apparatus and its connections shall be determined using a breathing machine with a sinusoidal characteristic adjusted to either 25 cycles/min and 2 l/stroke or 40 cycles/min and 2,5 l/stroke. A precision gauge shall be used. If necessary, the breathing resistance of the tubing and dummy head shall be subtracted from the measured value to determine the breathing resistance of the apparatus.

During the measurement the apparatus is in normal wearing position.

6.7 Leaktightness 6.7.1 Low pressure test

The apparatus is tested with the cylinder valve(s) closed and with the demand valve connected to a device which will create a negative and a positive pressure of 7,5 mbar and also to a manometer.

NOTE It may be necessary to seal the warning device during the negative pressure test.

6.7.2 High pressure test

The apparatus including the fully charged air cylinder(s) shall be assembled according to the manufacturer’s instructions.

The cylinder valve is opened and when the apparatus is completely pressurized, the cylinder valve(s) is (are) closed and the pressure drop is measured by observing the high pressure gauge of the apparatus.

When testing positive pressure apparatus the facepiece seal shall be completely sealed using a dummy head or similar.

After the cylinder valve has been opened the positive pressure device is actuated.

7 Marking

7.1 The manufacturer, supplier or importer shall be identified by name, trade mark or other means of identification.

7.2 Type identifying marking

7.3 The number of this European Standard

7.4 Serial number

7.5 Year of manufacture

7.6 Apparatus which meets the recommendations of Annex A should be marked with an “A”.

7.7 Where the reliable performance of components may be affected by ageing, the date (at least the year) of manufacture shall be marked.

7.8 Sub-assemblies and components with

considerable bearing on safety shall be marked so that they can be identified. If sub-assemblies with considerable bearing on safety are too small to be marked, the information shall be given in the instructions for use.

The pressure reducer shall be durably marked with a serial number. The marking shall be such that the year of production can be ascertained. In addition, provision shall be made to mark the date (year and month) and test marks of the last testing performed.

7.10 The marking shall be as clearly visible and as durable as possible.

8 Instructions for use

8.1 On delivery instructions for use shall accompany every apparatus enabling trained and qualified persons to use it.

8.2 Instructions for use shall be in the official language(s) of the country of application.

8.3 The instructions for use shall contain all information necessary for trained and qualified persons on

— application/limitation — checks prior to use — donning, fitting — use

— maintenance (preferably separately printed instructions)

— storage of the equipment.

8.4 The instructions shall include that the air supply shall meet the requirements for breathable air according to EN 132.

NOTE The figures given in EN 132 are valid if measured at normal conditions (atmospheric pressure, room temperature).

8.5 The instructions shall be unambiguous. If helpful, illustrations, part numbers, markings etc. shall be added.

8.6 Any other information the supplier may wish to provide.

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BS EN 137:1993

Annex A Recommendations for static

and dynamic pressure for apparatus

with thread connector in accordance

with EN 148-3

This annex is provided for apparatus which may be inadvertently connected to an existing facepiece with EN 148-3 thread connector. In the event of inadvertent coupling of such facepieces to EN 137 apparatus these additional clauses are

recommended to ensure safe compatibility. This annex does not imply that apparatus and facepieces which have not been tested and approved as complete apparatus may be used.

A.1 Static pressure

The lung governed demand valve of apparatus designed with a connector according to EN 148-3 shall maintain a static pressure of # 3,9 mbar in the positive pressure mode.

For testing, the lung governed demand valve shall be fitted with a cap that can be ventilated and has a port for measuring the pressure using a precision manometer. An air flow of 5 l/min shall be released for a short time. The static pressure shall be measured after the ventilation is shut off.

A.2 Dynamic pressure

A positive pressure shall be maintained when the apparatus is tested with a breathing machine (adjusted to 40 cycles/min, 2,5 l/stroke) at all cylinder pressures above 20 bar.

During the inhalation phase the positive pressure shall not exceed 4,2 mbar.

A.3 Exhalation valve

If the lung governed demand valve has an exhalation valve the opening pressure of this exhalation valve shall be at least 4,2 mbar measured at a continuous flow of 10 l/min.

A.4 For testing a test rig as shown schematically in Figure A.1 is used.

A breathing machine delivering sinusoidal flow shall be used. The pressure shall be measured at the port near the orifice. The orifice module shall be designed to have a resistance to airflow of 3,5 mbar at a continuous flow of 300 l/min.

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Personal Safety Equipment Standards Policy Committee (PSM/-) to Technical Committee PSM/14, upon which the following bodies were represented:

Asbestos Removal Contractors’ Association British Agrochemicals Association Ltd. British Coal Corporation

British Compressed Air Society British Nuclear Fuels Limited British Occupational Hygiene Society British Pest Control Association British Telecommunications plc Chemical Industries Association

Chief and Assistant Chief Fire Officers’ Association Electricity Supply Industry in England and Wales

Engineering Equipment and Materials Users’ Association Health and Safety Executive

Home Office

Industrial Safety (Protective Equipment) Manufacturers’ Association Institute of Occupational Hygienists

Institute of Occupational Medicine Institution of Fire Engineers

Institution of Mechanical Engineers Ministry of Defence

National Association of Fire Officers Safety Equipment Distributors’ Association Trades Union Congress

University of Aberdeen Coopted member

National annex NB (informative)

Cross-references

Publication referred to Corresponding British Standard

EN 132:1990 BS EN 132:1991 Respiratory protective devices — Definitions

EN 136:1989 BS 7355:1990 Specification for full face masks for respiratory protective devices EN 136-10 BS EN 136-10:1992 Specification for full face masks for respiratory protective

devices:

Part 10 Full face masks for special use

EN 142:1989 BS 7309:1990 Specification for mouthpiece assemblies for respiratory protective

devices

EN 148-1:1987 BS 7156:1987 Respiratory protective devices threads for facepieces Part 1:1990 Specification for standard thread

EN 148-2:1987 Part 2:1990 Specification for centre thread connnection

EN 148-3:1992 BS EN 148-3:1992 Respiratory protective devices: Threads for facepieces: Part 3 Thread connection M45 × 3

NOTE There is no British Standard equivalent to EN 144-2. This European Standard has not yet been published.

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