EN Official Journal of the European Union L 72/113

Only the original UN/ECE texts have legal effect under international public law. The status and date of entry into force of this Regulation should be checked in the latest version of the UN/ECE status document TRANS/WP.29/343, available at: http://www.unece.org/trans/main/wp29/wp29wgs/wp29gen/wp29fdocstts.html.

Regulation No 110 of the Economic Commission for Europe of the United Nations (UN/ECE) — Uniform provisions concerning the approval of:

I. Specific components of motor vehicles using compressed natural gas (CNG) in their propulsion system;

II. Vehicles with regard to the installation of specific components of an approved type for the use of compressed natural gas (CNG) in their propulsion system

Addendum 109: Regulation No 110

Supplement 6 to the original version of the Regulation — Date of entry into force: 18 June 2007

CONTENTS

REGULATION

1. Scope

2. Definition and classification of components

PART I

3. Application for approval

4. Markings

5. Approval

6. Specifications regarding CNG components

7. Modifications of a type of CNG component and extension of approval

8. (Not allocated)

9. Conformity of production

10. Penalties for non-conformity of production

11. (Not allocated)

12. Production definitely discontinued

13. Names and addresses of technical services responsible for conducting approval tests, and of administrative departments

PART II

14. Definitions

15. Application for approval

16. Approval

17. Requirements for the installation of specific components for the use of compressed natural gas in the propulsion system of a vehicle

18. Conformity of production

19. Penalties for non-conformity of production

20. Modification and extension of approval of a vehicle type

21. Production definitely discontinued

22. Names and addresses of technical services responsible for conducting approval tests, and of administrative departments

ANNEXES

Annex 1A — Essential characteristics of the CNG component

Annex 1B — Essential characteristics of the vehicle, engine and CNG-related system

Annex 2A — Arrangement of the CNG component type-approval mark

Annex 2B — Communication concerning the approval or extension or refusal or withdrawal of approval or production definitely discontinued of a type of CNG component pursuant to Regulation No 110

Addendum — Additional information concerning the type-approval of a type of CNG components pursuant to Regulation No 110

Annex 2C — Arrangement of approval marks

Annex 2D — Communication concerning the approval or extension or refusal or withdrawal of approval or production definitely discontinued of a vehicle type with regard to the installation of CNG system pursuant to Regulation No 110

Annex 3 — Gas cylinders — High pressure cylinder for the on-board storage of natural gas as a fuel for automotive vehicles

Appendix A — Test methods

Appendix B — (Not allocated)

Appendix C — (Not allocated)

Appendix D — Report Forms

Appendix E — Verification of stress ratios using strain gauges

Appendix F — Fracture performance methods

Appendix G — Instructions by the container manufacturer regarding handling, use and inspection of cylinders

Appendix H — Environmental test

Annex 4A — Provisions regarding the approval of the automatic valve, non-return valve, the pressure relief valve, pressure relief device and the excess flow valve

Annex 4B — Provisions regarding the approval of flexible fuel lines or hoses

Annex 4C — Provisions regarding the approval of the CNG filter

Annex 4D — Provisions regarding the approval of the pressure regulator

Annex 4E — Provisions regarding the approval of the pressure and temperature sensors

Annex 4F — Provisions regarding the approval of the filling unit

Annex 4G — Provisions regarding the approval of gas flow adjuster and gas/air mixer or injector

Annex 4H — Provisions regarding the approval of the electronic control unit

Annex 5 — Test procedures

Annex 5A — Overpressure test (Strength test)

Annex 5B — External leakage test

Annex 5C — Internal leakage test

Annex 5D — CNG compatibility test

Annex 5E — Corrosion resistance test

Annex 5F — Resistance to dry heat

Annex 5G — Ozone ageing

Annex 5H — Temperature cycle test

Annex 5I — Pressure cycle test applicable only to cylinders (see annex 3)

Annex 5J — (Not allocated)

Annex 5K — (Not allocated)

Annex 5L — Durability test (Continued operation)

Annex 5M — Burst/destructive test applicable only to cylinders (see annex 3)

Annex 5N — Vibration resistance test

Annex 5O — Operating temperatures

Annex 6 — Provisions regarding CNG identification mark for public service vehicles

1. SCOPE

This Regulation applies to:

Part I : Specific components for vehicles of category M and N (1) using compressed natural gas (CNG) in their propulsion system;

Part II : Vehicles of category M and N (1) with regard to the installation of specific components, for the use of compressed natural gas (CNG) for propulsion, of an approved type.

2. DEFINITION AND CLASSIFICATION OF COMPONENTS

CNG components for use in vehicles shall be classified with regard to the working pressure and function, according to figure 1-1.

Class 0 High pressure parts including tubes and fittings containing CNG at a pressure higher than 3 MPa and up to 26 MPa. Class 1 Medium pressure parts including tubes and fittings containing CNG at a pressure higher than 450 kPa and up to 3 000 kPa (3 MPa). Class 2 Low pressure parts including tubes and fittings containing CNG at a pressure higher than 20 kPa and up to 450 kPa. Class 3 Medium pressure parts as safety valves or protected by safety valve including tubes and fittings containing CNG at a pressure higher than 450 kPa and up to 3 000 kPa (3 MPa). Class 4 Parts in contact with gas subject to the pressure lower than 20 kPa.

A component can consist of several parts, each part classified in its own class with regard to maximum working pressure and function.

‘Pressure’ means relative pressure versus atmospheric pressure, unless otherwise stated.

2.1.1. ‘Service pressure’ means the settled pressure at a uniform gas temperature of 15 °C.

2.1.2. ‘Test pressure’ means the pressure to which a component is taken during acceptance testing.

2.1.3. ‘Working pressure’ means the maximum pressure to which a component is designed to be subjected to and which is the basis for determining the strength of the component under consideration.

2.1.4. ‘Operating temperatures’ means maximum values of the temperature ranges, indicated in Annex 5O, at which safe and good functioning of the specific component is ensured and for which it has been designed and approved.

‘Specific component’ means:

(a) container (or cylinder),

(b) accessories fitted to the cylinder

(c) pressure regulator,

(d) automatic valve,

(e) manual valve,

(f) gas supply device,

(g) gas flow adjuster,

(h) flexible fuel line,

(i) rigid fuel line,

(j) filling unit or receptacle,

(k) non-return valve or non-return valve,

(l) pressure relief valve (discharge valve),

(m) pressure relief device (temperature triggered),

(n) filter,

(o) pressure or temperature sensor/indicator,

(p) excess flow valve,

(q) service valve,

(r) electronic control unit,

(s) gas-tight housing,

(t) fitting,

(u) ventilation hose.

Many of the components mentioned above can be combined or fitted together as a ‘multi-functional component’.

Fig. 1-1

Flow scheme for CNG components classification

Fig. 1-2

Tests applicable to specific classes of components (excluding cylinders)

Performance Test Over-pressure Strength Test Leakage Test (external) Leakage Test (internal) Continued Operation Durability Test Corrosion Resistance Ozone Ageing CNG Compatibility Vibration Resistance Dry — Heat Resistance Annex 5A Annex 5B Annex 5C Annex 5L Annex 5E Annex 5G Annex 5D Annex 5N Annex 5F Class 0 X X A A X X X X X Class 1 X X A A X X X X X Class 2 X X A A X A X X A Class 3 X X A A X X X X X Class 4 O O O O X A X O A X = Applicable O = Not applicable A = As applicable

‘Container’ (or cylinder) means any vessel used for the storage of compressed natural gas;

2.3.1. A container can be:

CNG-1 : metal; CNG-2 : metal liner reinforced with resin impregnated continuous filament (hoop wrapped); CNG-3 : metal liner reinforced with resin impregnated continuous filament (fully wrapped); CNG-4 : resin impregnated continuous filament with a non-metallic liner (all composite).

2.4. ‘Type of container’ means containers which do not differ in respect of the dimensional and material characteristics as specified in annex 3.

‘Accessories fitted to the container’ means the following components (but not limited to them), either separate or combined, when fitted to the container:

2.5.1. Manual valve;

2.5.2. Pressure sensor/indicator;

2.5.3. Pressure relief valve (discharge valve);

2.5.4. Pressure relief device (temperature triggered);

2.5.5. Automatic cylinder valve;

2.5.6. Excess flow valve;

2.5.7. Gas-tight housing.

2.6. ‘Valve’ means a device by which the flow of a fluid may be controlled.

2.7. ‘Automatic valve’ mans a valve which is not operated manually.

2.8. ‘Automatic cylinder valve’ means an automatic valve rigidly fixed to the cylinder which controls the flow of gas to the fuel system. The automatic cylinder valve is also called remote-controlled service valve.

2.9. ‘Non-return valve’ means an automatic valve which allows gas to flow in only one direction.

2.10. ‘Excess flow valve’ (excess flow limiting device) means a device which automatically shuts off, or limits, the gas flow when the flow exceeds a set design value.

2.11. ‘Manual valve’ means a manual valve rigidly fixed to the cylinder.

2.12. ‘Pressure relief valve (discharge valve)’ means a device which prevents a pre-determined upstream pressure being exceeded.

2.13. ‘Service valve’ means an isolation valve which is closed only when servicing the vehicle.

2.14. ‘Filter’ means a protective screen which removes foreign debris from the gas stream.

2.15. ‘Fitting’ means a connector used in a piping, tubing, or hose system.

Fuel lines

2.16.1. ‘Flexible fuel lines’ mean a flexible tubing or hose through which natural gas flow.

2.16.2. ‘Rigid fuel lines’ mean a tubing which has not been designed to flex in normal operation and through which natural gas flows.

‘Gas supply device’ means a device for introducing gaseous fuel into the engine intake manifold (carburettor or injector).

2.17.1. ‘Gas/air mixer’ means a device for mixing the gaseous fuel and intake air for the engine.

2.17.2. ‘Gas injector’ means a device for introducing gaseous fuel into the engine or associated intake system.

2.18. ‘Gas flow adjuster’ means a gas flow restricting device, installed downstream of a pressure regulator, controlling gas flow to the engine.

2.19. ‘Gas-tight housing’ means a device which vents gas leakage to outside the vehicle including the gas ventilation hose.

2.20. ‘Pressure indicator’ means a pressurised device which indicates the gas pressure.

2.21. ‘Pressure regulator’ means a device used to control the delivery pressure of gaseous fuel to the engine.

2.22. ‘Pressure relief device (temperature triggered)’ means a one time use device triggered by excessive temperature and/or pressure which vents gas to protect the cylinder from rupture.

2.23. ‘Filling unit or receptacle’ means a device fitted in the vehicle external or internal (engine compartment) used to fill the container in the filling station.

2.24. ‘Electronic control unit (CNG — fuelling)’ means a device which controls the gas demand of the engine, and other engine parameters, and cuts off automatically the automatic valve, required by safety reason.

2.25. ‘Type of components’ as mentioned in paragraphs 2.6. to 2.23. above means components which do not differ in such essential respect as materials, working pressure and operating temperatures.

2.26. ‘Type of electronic control unit’ as mentioned in paragraph 2.24. means components which do not differ in such essential respect as the basic software principles excluding minor changes.

PART I

APPROVAL OF SPECIFIC COMPONENTS OF MOTOR VEHICLES USING COMPRESSED NATURAL GAS (CNG) IN THEIR PROPULSION SYSTEM

3. APPLICATION FOR APPROVAL

3.1. The application for approval of specific component or multifunctional component shall be submitted by the holder of the trade name or mark or by his duly accredited representative.

It shall be accompanied by the under-mentioned documents in triplicate and by the following particulars:

3.2.1. description of the vehicle comprising all the relevant particulars referred to in annex 1A to this Regulation,

3.2.2. a detailed description of the type of the specific component,

3.2.3. a drawing of the specific component, sufficiently detailed and on an appropriate scale,

3.2.4. verification of compliance with the specifications prescribed in paragraph 6 of this Regulation.

At the request of the technical service responsible for conducting approval tests, samples of the specific component shall be provided. Supplementary samples shall be supplied upon request (3 maximum)

3.3.1. During pre-production of containers [n] (2), containers of each 50 pieces (lot of qualification) shall be subject to non-destructive tests of annex 3.

4. MARKINGS

4.1. The sample of specific component submitted for approval shall bear the trade name or mark of the manufacturer and the type, including one concerning designation regarding operating temperatures (‘M’ or ‘C’ for moderate or cold temperatures as appropriate); and for flexible hoses also the manufacturing month and year; this marking shall be clearly legible and indelible.

4.2. All components shall have a space large enough to accommodate the approval mark; this space shall be shown on the drawings referred to in paragraph 3.2.3. above.

4.3. Every container shall also bear a marking plate with the following data clearly legible and indelible:

(a) a serial number;

(b) the capacity in litres;

(c) the marking ‘CNG’;

(d) operating pressure/test pressure [MPa];

(e) mass (kg);

(f) year and month of approval (e.g. 96/01);

(g) approval mark according to paragraph 5.4.

5. APPROVAL

5.1. If the component samples submitted for approval meet the requirements of paragraphs 6.1. to 6.11. of this Regulation, approval of the type of component shall be granted.

5.2. An approval number shall be assigned to each type of component or multifunctional component approved. Its first two digits (at present 00 for the Regulation in its original form) shall indicate the series of amendments incorporating the most recent major technical amendments made to the Regulation at the time of issue of the approval. The same Contracting Party shall not assign the same alphanumeric code to another type of component.

5.3. Notice of approval or of refusal or of extension of approval of a CNG component type pursuant to this Regulation shall be communicated to the Parties to the Agreement applying this Regulation, by means of a form conforming to the model in annex 2B to this Regulation.

There shall be affixed, conspicuously and in the space referred to in paragraph 4.2. above, to all components conforming to a type approved under this Regulation, in addition to the mark prescribed in paragraphs 4.1. and 4.3., an international approval mark consisting of:

5.4.1. A circle surrounding the letter ‘E’ followed by the distinguishing number of the country which has granted approval (3).

5.4.2. The number of this Regulation, followed by the letter ‘R’, a dash and the approval number to the right of the circle prescribed in paragraph 5.4.1. This approval number consists of the component type-approval number which appears on the certificate completed for this type (see paragraph 5.2. and annex 2B) preceded by two figures indicating the sequence of the latest series of amendments to this Regulation.

5.5. The approval mark shall be clearly legible and be indelible.

5.6. Annex 2A to this Regulation gives examples of the arrangement of the aforesaid approval mark.

6. SPECIFICATIONS REGARDING CNG COMPONENTS

6.1. General provisions

6.1.1. The specific components of vehicles using CNG in their propulsion system shall function in a correct and safe way as specified in this Regulation.

The materials of the components which are in contact with CNG shall be compatible with it (see annex 5D).

Those parts of component whose correct and safe functioning is liable to be influenced by CNG, high pressure or vibrations has to be submitted to relevant test procedures described in the annexes of this Regulation. In particular the provisions of paragraphs 6.2. to 6.11. are to be fulfilled.

The specific components of vehicles using CNG in their propulsion system shall comply with relevant electromagnetic compatibility (EMC) requirements according to Regulation No 10, 02 series of amendments, or equivalent.

6.2. Provisions regarding containers

6.2.1. The CNG containers shall be type approved pursuant to the provisions laid down in annex 3 to this Regulation.

6.3. Provisions regarding components fitted to the container

The container shall be equipped at least with the following components, which may be either separate or combined:

6.3.1.1. manual valve,

6.3.1.2. automatic cylinder valve,

6.3.1.3. pressure relief device,

6.3.1.4. excess flow limiting device.

6.3.2. The container may be equipped with a gas-tight housing, if necessary.

6.3.3. The components mentioned in paragraphs 6.3.1. to 6.3.2. above shall be type approved pursuant to the provisions laid down in annex 4 to this Regulation.

6.4.-6.11. Provisions regarding other components

The components shown shall be type approved pursuant to the provisions laid down in the annexes which can be determined from the table below:

Paragraph Component Annex 6.4. Automatic valve Non-return valve or non-return valve Pressure relief valve Pressure relief device Excess flow valve 4A 6.5. Flexible fuel line-hose 4B 6.6. CNG filter 4C 6.7. Pressure regulator 4D 6.8. Pressure and temperature sensors 4E 6.9. Filling unit or receptacle 4F 6.10. Gas flow adjuster and gas/air mixer or injector 4G 6.11. Electronic control unit 4H

7. MODIFICATIONS OF A TYPE OF CNG COMPONENT AND EXTENSION OF APPROVAL

Every modification of a type of CNG component shall be notified to the administrative department which granted the type-approval. The department may then either:

7.1.1. Consider that the modifications made are unlikely to have an appreciable adverse effect, and that the component still complies with the requirements; or

7.1.2. Determine whether partial or complete retesting has to be established by the competent authority.

7.2. Confirmation or refusal of approval, specifying the alterations, shall be communicated by the procedure specified in paragraph 5.3. above to the Parties to the Agreement which apply this Regulation.

7.3. The competent authority issuing the extension of approval shall assign a series number to each communication form drawn up for such an extension.

8. (Not allocated)

9. CONFORMITY OF PRODUCTION

The conformity of production procedures shall comply with those set out in the Agreement, appendix 2 (E/ECE/324-E/ECE/TRANS/505/Rev.2) with the following requirements:

9.1. Every container shall be tested at a minimum pressure of 1,5 times the working pressure in conformity with the prescriptions of annex 3 of this Regulation.

9.2. Burst testing under hydraulic pressure according to paragraph 3.2. of annex 3 shall be carried out for each lot consisting of max 200 containers manufactured with the same lot of raw material.

9.3. Every flexible fuel line assembly which is applied in the high and medium pressure (Class 0, 1) according to the Classification as described in paragraph 2 of this Regulation, shall be tested at the pressure twice the working pressure.

10. PENALTIES FOR NON-CONFORMITY OF PRODUCTION

10.1. The approval granted in respect of a type of component pursuant to this Regulation may be withdrawn if the requirements laid down in paragraph 9 above are not complied with.

10.2. If a Party to the Agreement applying this Regulation withdraws an approval it has previously granted, it shall forthwith so notify the other Contracting Parties applying this Regulation, by means of a communication form conforming to the model in annex 2B to this Regulation.

11. (Not allocated)

12. PRODUCTION DEFINITELY DISCONTINUED

If the holder of the approval completely ceases to manufacture a type of component approved in accordance with this Regulation, he shall so inform the authority which granted the approval. Upon receiving the relevant communication, that authority shall inform thereof the other Parties to the Agreement applying this Regulation by means of a communication form conforming to the model in annex 2B to this Regulation.

13. NAMES AND ADDRESSES OF TECHNICAL SERVICES RESPONSIBLE FOR CONDUCTING APPROVAL TESTS, AND OF ADMINISTRATIVE DEPARTMENTS

The Parties to the Agreement applying this Regulation shall communicate to the United Nations Secretariat the names and addresses of the technical services responsible for conducting approval tests and of the administrative departments which grant approval and to which forms certifying approval or extension or refusal or withdrawal of approval, issued in other countries, are to be sent.

PART II

APPROVAL OF VEHICLES WITH REGARD TO THE INSTALLATION OF SPECIFIC COMPONENTS OF AN APPROVED TYPE FOR THE USE OF COMPRESSED NATURAL GAS (CNG) IN THEIR PROPULSION SYSTEM

14. DEFINITIONS

For the purposes of Part II of this Regulation:

14.1.1. ‘Approval of a vehicle’ means the approval of a vehicle type of categories M and N with regard to its CNG system as an original equipment for the use in its propulsion system;

‘Vehicle type’ means vehicles fitted with specific components for the use of CNG in their propulsion system which do not differ with respect to the following conditions:

14.1.2.1. the manufacturer;

14.1.2.2. the type designation established by the manufacturer,

the essential aspects of design and construction:

14.1.2.3.1. chassis/floor pan (obvious and fundamental differences);

14.1.2.3.2. the installation of the CNG equipment(obvious and fundamental differences).

14.1.3. ‘CNG system’ means an assembly of components (container(s) or cylinder(s), valves, flexible fuel lines, etc.) and connecting parts (rigid fuel lines, pipes fitting, etc.) fitted on motor vehicles using CNG in their propulsion system.

15. APPLICATION FOR APPROVAL

15.1. The application for approval of a vehicle type with regard to the installation of specific components for the use of compressed natural gas in its propulsion system shall be submitted by the vehicle manufacturer or by his duly accredited representative.

15.2. It shall be accompanied by the under-mentioned documents in triplicate: description of the vehicle comprising all the relevant particulars referred to in annex 1B to this Regulation.

15.3. A vehicle representative of the vehicle type to be approved, shall be submitted to the technical service conducting the approval tests.

16. APPROVAL

16.1. If the vehicle submitted for approval pursuant to this Regulation is provided with all the necessary specific components for the use of compressed natural gases in its propulsion system and meets the requirements of paragraph 17 below, approval of that vehicle type shall be granted.

16.2. An approval number shall be assigned to each type of vehicle approved. Its first two digits shall indicate the series of amendments incorporating the most recent major technical amendments made to the Regulation at the time of issue of the approval.

16.3. Notice of approval or of refusal or of extension of approval of a CNG vehicle type pursuant to this Regulation shall be communicated to the Parties to the Agreement applying this Regulation, by means of a form conforming to the model in annex 2D to this Regulation.

There shall be affixed, conspicuously and in a readily accessible space specified on the approval form referred to in paragraph 16.2. above, to every vehicle type approved under this Regulation an international approval mark consisting of:

16.4.1. A circle surrounding the letter ‘E’ followed by the distinguishing number of the country which has granted approval (3);

16.4.2. The number of this Regulation, followed by the letter ‘R’, a dash and the approval number to the right of the circle prescribed in paragraph 16.4.1.

16.5. If the vehicle conforms to a vehicle approved, under one or more other Regulations annexed to the Agreement, in the country which has granted approval under this Regulation, the symbol prescribed in paragraph 16.4.1. need not be repeated; in such case, the Regulation and approval numbers and the additional symbols of all the Regulations under which approval has been granted in the country which has granted approval under this Regulation shall be placed in vertical columns to the right of the symbol prescribed in paragraph 16.4.1.

16.6. The approval mark shall be clearly legible and be indelible.

16.7. The approval mark shall be placed close to or on the vehicle data plate.

16.8. Annex 2C to this Regulation gives examples of the arrangement of the aforesaid approval mark.

17. REQUIREMENTS FOR THE INSTALLATION OF SPECIFIC COMPONENTS FOR THE USE OF COMPRESSED NATURAL GAS IN THE PROPULSION SYSTEM OF A VEHICLE

17.1. General

17.1.1. The CNG system of the vehicle shall function in a good and safe manner at the working pressure and operating temperatures for which it has been designed and approved.

17.1.2. All components of the system shall be type approved as individual parts pursuant to Part I of this Regulation.

17.1.3. The materials used in the system shall be suitable for use with CNG.

17.1.4. All components of the system shall be fastened in a proper way.

17.1.5. The CNG system shall show no leaks, i.e. stay bubble-free for 3 minutes.

17.1.6. The CNG system shall be installed such that is has the best possible protection against damage, such as damage due to moving vehicle components, collision, grit or due to the loading or unloading of the vehicle or the shifting of those loads.

No appliances shall be connected to the CNG system other than those strictly required for the proper operation of the engine of the motor vehicle.

17.1.7.1. Notwithstanding the provisions of paragraph 17.1.7., vehicles may be fitted with a heating system to heat the passenger compartment and/or the load area which is connected to the CNG system.

17.1.7.2. The heating system referred to in paragraph 17.1.7.1. shall be permitted if, in the view of the technical services responsible for conducting type-approval, the heating system is adequately protected and the required operation of the normal CNG system is not affected.

Identification of CNG-fuelled vehicles of categories M2 and M3 (4).

17.1.8.1. Vehicles of categories M2 and M3 equipped with a CNG system shall carry a plate as specified in annex 6.

17.1.8.2. The plate shall be installed on the front and rear of the vehicle of category M2 or M3 and on the outside of the doors on the right-hand side.

17.2. Further requirements

17.2.1. No component of the CNG system, including any protective materials which form part of such components, shall project beyond the outline of the vehicle, with the exception of the filling unit if this does not project more than 10 mm beyond its point of attachment.

17.2.2. No component of the CNG system shall be located within 100 mm of the exhaust or similar heat source, unless such components are adequately shielded against heat.

17.3. The CNG system

A CNG system shall contain at least the following components:

17.3.1.1. Container(s) or cylinder(s);

17.3.1.2. Pressure indicator or fuel level indicator;

17.3.1.3. Pressure relief device (temperature triggered);

17.3.1.4. Automatic cylinder valve;

17.3.1.5. Manual valve;

17.3.1.6. Pressure regulator;

17.3.1.7. Gas flow adjuster;

17.3.1.8. Excess flow limiting device;

17.3.1.9. Gas supply device;

17.3.1.10. Filling unit or receptacle;

17.3.1.11. Flexible fuel line;

17.3.1.12. Rigid fuel line;

17.3.1.13. Electronic control unit;

17.3.1.14. Fittings;

17.3.1.15. Gas-tight housing for those components installed inside the luggage and passenger compartment. If the gas-tight housing will be destroyed in case of fire, the pressure relief device may be covered by the gas-tight housing.

The CNG system may also include the following components:

17.3.2.1. Non-return valve or non-return valve;

17.3.2.2. Pressure relief valve;

17.3.2.3. CNG filter;

17.3.2.4. Pressure and/or temperature sensor;

17.3.2.5. Fuel selection system and electrical system.

17.3.3. An additional automatic valve may be combined with the pressure regulator.

17.4. Installation of the container

17.4.1. The container shall be permanently installed in the vehicle and shall not be installed in the engine compartment.

17.4.2. The container shall be installed such that there is no metal to metal contact, with the exception of the fixing points of the container(s).

When the vehicle is ready for use the fuel container shall not be less than 200 mm above the road surface.

17.4.3.1. The provisions of paragraph 17.4.3. shall not apply if the container is adequately protected, at the front and the sides and no part of the container is located lower than this protective structure.

17.4.4. The fuel container(s) or cylinder(s) must be mounted and fixed so that the following accelerations can be absorbed (without damage occurring) when the containers are full:

Vehicles of categories M1 and N1:

(a) 20 g in the direction of travel

(b) 8 g horizontally perpendicular to the direction of travel

Vehicles of categories M2 and N2:

(a) 10 g in the direction of travel

(b) 5 g horizontally perpendicular to the direction of travel

Vehicles of categories M3 and N3:

(a) 6,6 g in the direction of travel

(b) 5 g horizontally perpendicular to the direction of travel

A calculation method can be used instead of practical testing if its equivalence can be demonstrated by the applicant for approval to the satisfaction of the technical service.

17.5. Accessories fitted to the container(s) or cylinder(s)

Automatic valve

17.5.1.1. An automatic cylinder valve shall be installed directly on each container.

17.5.1.2. The automatic cylinder valve shall be operated such that the fuel supply is cut off when the engine is switched off, irrespective of the position of the ignition switch, and shall remain closed while the engine in not running. A delay of 2 seconds is permitted for diagnostic.

Pressure relief device

17.5.2.1. The pressure relief device (temperature triggered) shall be fitted to the fuel container(s) in such a manner that can discharge into the gas-tight housing if that gas-tight housing fulfils the requirements of paragraph 17.5.5.

Excess flow valve on the container

17.5.3.1. The excess flow limiting device shall be fitted in the fuel container(s) on the automatic cylinder valve.

Manual valve

17.5.4.1. A manual valve is rigidly fixed to the cylinder which can be integrated into the automatic cylinder valve.

Gas-tight housing on the container(s)

17.5.5.1. A gas-tight housing over the container(s) fittings, which fulfils the requirements of paragraphs 17.5.5.2. to 17.5.5.5. shall be fitted to the fuel container, unless the container(s) is installed outside the vehicle.

17.5.5.2. The gas-tight housing shall be in open connection with the atmosphere, where necessary through a connecting hose and a lead-through which shall be resistant against CNG.

17.5.5.3. The ventilation opening of the gas tight housing shall not discharge into a wheel arch, nor shall it be aimed at a heat source such as the exhaust.

17.5.5.4. Any connecting hose and lead-through in the bottom of the bodywork of the motor vehicle for ventilation of the gas-tight housing shall have a minimum clear opening of 450 mm2.

17.5.5.5. The housing over the container(s) fittings and connecting hoses shall be gas-tight at a pressure of 10 kPa without any permanent deformations. In this circumstances a leak not exceeding 100 cm3 per hour may be accepted.

17.5.5.6. The connecting hose shall be secured by clamps, or other means, to the gas-tight housing and the lead-through to ensure that a gas-tight joint is formed.

17.5.5.7. The gas-tight housing shall contain all the components installed into the luggage or passenger compartment.

17.6. Rigid and flexible fuel lines

17.6.1. Rigid fuel lines shall be made of seamless material: either stainless steel or steel with corrosion-resistant coating.

17.6.2. The rigid fuel line may be replaced by a flexible fuel line if used in Class 0, 1 or 2.

17.6.3. Flexible fuel line shall fulfil the requirement of annex 4B to this Regulation.

17.6.4. Rigid fuel lines, shall be secured such that they shall not be subjected to vibration of stresses.

17.6.5. Flexible fuel lines shall be secured such that they shall not be subjected to vibration or stresses.

17.6.6. At the fixing point, the fuel line, flexible or rigid, shall be fitted in such a way that there is no metal to metal contact.

17.6.7. Rigid and flexible fuel gas line shall not be located at jacking points.

17.6.8. At passages the fuel lines shall be fitted with protective material.

17.7. Fitting or gas connections between the components

17.7.1. Soldered joints and bite-type compression joints are not permitted.

17.7.2. Stainless steel tubes shall only be joined by stainless steel fittings.

17.7.3. Distributing-blocks shall be made of corrosion-resistant material.

17.7.4. Rigid fuel lines shall be connected by appropriate joints, for example, two-part compression joints in steel tubes and joints with olives tapered on both sides.

17.7.5. The number of joints shall be limited to a minimum.

17.7.6. Any joints shall be made in locations where access is possible for inspection.

In a passenger compartment or enclosed luggage compartment the fuel lines shall be no longer than reasonably required, and in any case shall be protected by a gas-tight housing.

17.7.7.1. The provisions of paragraph 17.7.7. shall not apply to vehicles of categories M2 or M3 where the fuel lines and connections are fitted with a sleeve which is resistant against CNG and which has an open connection to the atmosphere.

17.8. Automatic valve

17.8.1. An additional automatic valve may be installed in the fuel line as close as possible to the pressure regulator.

17.9. Filling unit or receptacle

17.9.1. The filling unit shall be secured against rotation and shall be protected against dirt and water.

17.9.2. When the CNG container is installed in the passenger compartment or a enclosed (luggage) compartment the filling unit shall be located at the outside of the vehicle or in engine compartment.

17.10. Fuel selection system and electrical installation

17.10.1. The electrical components of the CNG system shall be protected against overloads.

17.10.2. Vehicles with more than one fuel system shall have a fuel selection system to ensure that no more than one fuel at the same time is supplied to the engine for more than 5 seconds. ‘Dual-fuel’ vehicles, using diesel as the primary fuel for igniting the air/gas mixture, are allowed in cases where these engines and vehicles meet mandatory emission standards.

17.10.3. The electrical connections and components in the gas-tight housing shall be constructed such that no sparks are generated.

18. CONFORMITY OF PRODUCTION

18.1. The conformity of production procedures shall comply with those set out in the Agreement, appendix 2 (E/ECE/324-E/ECE/TRANS/505/Rev.2).

19. PENALTIES FOR NON-CONFORMITY OF PRODUCTION

19.1. The approval granted in respect of a type of vehicle pursuant to this Regulation may be withdrawn if the requirements referred to in paragraph 18 above are not complied with.

19.2. If a Party to the Agreement applying this Regulation withdraws an approval it has previously granted, it shall forthwith so notify the other Contracting Parties applying this Regulation, by means of a communication form conforming to the model in annex 2D to this Regulation.

20. MODIFICATION AND EXTENSION OF APPROVAL OF A VEHICLE TYPE

Every modification of the installation of the specific components for the use of compressed natural gas in the propulsion system of the vehicle shall be notified to the administrative department which approved the vehicle type. The department may then either:

20.1.1. Consider that the modifications made are unlikely to have an appreciably adverse effect and that in any case the vehicle still complies with the requirements; or

20.1.2. Require a further test report from the technical service responsible for conducting the tests.

20.2. Confirmation or refusal of approval, specifying the alteration, shall be communicated to the Parties to the Agreement applying this Regulation by means of a form conforming to the model in annex 2D to this Regulation.

20.3. The competent authority issuing the extension of approval shall assign a series number for such an extension and inform thereof the other Parties to the 1958 Agreement applying this Regulation by means of a communication form conforming to the model in annex 2D to this Regulation.

21. PRODUCTION DEFINITELY DISCONTINUED

If the holder of the approval completely ceases to manufacture a type of vehicle approved in accordance with this Regulation, he shall so inform the authority which granted the approval. Upon receiving the relevant communication, that authority shall inform thereof the other Parties to the Agreement applying this Regulation by means of a communication form conforming to the model in annex 2D to this Regulation.

22. NAMES AND ADDRESSES OF TECHNICAL SERVICES RESPONSIBLE FOR CONDUCTING APPROVAL TESTS, AND OF ADMINISTRATIVE DEPARTMENTS

The Parties to the Agreement applying this Regulation shall communicate to the United Nations Secretariat the names and addresses of the technical services responsible for conducting approval tests and of the administrative departments which grant approval and to which forms certifying approval or extension or refusal or withdrawal of approval, issued in other countries, are to be sent.

(1) As defined in Annex 7 to the Consolidated Resolution on the Construction of Vehicles (R.E.3), (document TRANS/WP.29/78/Rev.1/Amend.2 as last amended by Amend.4).

(2) To be specified.

(3) 1 for Germany, 2 for France, 3 for Italy, 4 for the Netherlands, 5 for Sweden, 6 for Belgium, 7 for Hungary, 8 for the Czech Republic, 9 for Spain, 10 for Serbia, 11 for the United Kingdom, 12 for Austria, 13 for Luxembourg, 14 for Switzerland, 15 (vacant), 16 for Norway, 17 for Finland, 18 for Denmark, 19 for Romania, 20 for Poland, 21 for Portugal, 22 for the Russian Federation, 23 for Greece, 24 for Ireland, 25 for Croatia, 26 for Slovenia, 27 for Slovakia, 28 for Belarus, 29 for Estonia, 30 (vacant), 31 for Bosnia and Herzegovina, 32 for Latvia, 33 (vacant), 34 for Bulgaria, 36 for Lithuania, 37 for Turkey, 38 (vacant), 39 for Azerbaijan, 40 for The former Yugoslav Republic of Macedonia, 41 (vacant), 42 for the European Community (Approvals are granted by its Member States using their respective ECE symbol), 43 for Japan, 44 (vacant), 45 for Australia, 46 for Ukraine and 47 for South Africa, 48 for New Zealand, 49 for Cyprus, 50 for Malta, 51 for the Republic of Korea, 52 for Malaysia, 53 for Thailand, 54 and 55 (vacant) and 56 for Montenegro. Subsequent numbers shall be assigned to other countries in the chronological order in which they ratify or accede to the Agreement Concerning the Adoption of Uniform Technical Prescriptions for Wheeled Vehicles, Equipment and Parts which can be Fitted and/or be Used on Wheeled Vehicles and the Conditions for Reciprocal Recognition of Approvals Granted on the Basis of these Prescriptions, and the numbers thus assigned shall be communicated by the Secretary-General of the United Nations to the Contracting Parties to the Agreement.

(4) As defined in the Consolidated Resolution on the Construction of Vehicles (R.E.3), annex 7 (TRANS/WP.29/78/Rev.1/Amend.2).

ANNEX 1A ESSENTIAL CHARACTERISTICS OF THE CNG COMPONENT

ANNEX 1B ESSENTIAL CHARACTERISTICS OF THE VEHICLE, ENGINE AND CNG-RELATED SYSTEM

ANNEX 2A ARRANGEMENT OF THE CNG COMPONENT TYPE-APPROVAL MARK (See paragraph 5.2. of this Regulation) The above approval mark affixed to the CNG component shows that this component has been approved in Italy (E3), pursuant to Regulation No. 110 under approval number 002439. The first two digits of the approval number indicate that the approval was granted in accordance with the requirements of Regulation No. 110 in its original form.

ANNEX 2B COMMUNICATION Addendum

ANNEX 2C ARRANGEMENT OF APPROVAL MARKS MODEL A (See paragraph 16.2. of this Regulation) The above approval mark affixed to a vehicle shows that the vehicle has, with regard to the installation of CNG system for the use of CNG for propulsion, been approved in Italy (E3), pursuant to Regulation No. 110 under approval number 002439. The first two digits of the approval number indicate that the approval was granted in accordance with the requirements of Regulation No. 110 in its original form. MODEL B (See paragraph 16.2. of this Regulation) The above approval mark affixed to a vehicle shows that the vehicle has, with regard to the installation of CNG system for the use of CNG for propulsion, been approved in Italy(E3), pursuant to Regulation No. 110 under approval number 002439. The first two digits of the approval number indicate that at the date the approval was granted in accordance with the requirements of Regulation No. 110 in its original form and that Regulation No. 83 included the 04 series of amendments.

ANNEX 2D COMMUNICATION

ANNEX 3 GAS CYLINDERS HIGH PRESSURE CYLINDER FOR THE ON-BOARD STORAGE OF NATURAL GAS AS A FUEL FOR AUTOMOTIVE VEHICLES 1. SCOPE This annex sets out minimum requirements for light-weight refillable gas cylinders. The cylinders are intended only for the on-board storage of high pressure compressed natural gas as a fuel for automotive vehicles to which the cylinders are to be fixed. Cylinders may be of any steel, aluminium or non-metallic material, design or method of manufacture suitable for the specified service conditions. This annex does not cover metal liners or cylinders of stainless steels or of welded construction. Cylinders covered by this annex are Classified in Class 0, as described in paragraph 2. of this Regulation, and are: CNG-1 Metal CNG-2 Metal liner reinforced with resin impregnated continuous filament (hoop wrapped) CNG-3 Metal liner reinforced with resin impregnated continuous filament (fully wrapped) CNG-4 Resin impregnated continuous filament with a non-metallic liner (all composite) Service conditions to which the cylinders will be subjected are detailed in paragraph 4. This annex is based upon a working pressure for natural gas as a fuel of 20 MPa settled at 15 °C with a maximum filling pressure of 26 MPa. Other working pressures can be accommodated by adjusting the pressure by the appropriate factor (ratio). For example, a 25 MPa working pressure system will require pressures to be multiplied by 1,25. The service life of the cylinder shall be defined by the manufacturer and may vary with applications. Definition of service life is based upon filling the cylinders 1 000 times a year for a minimum of 15 000 fills. The maximum service life shall be 20 years. For metal and metal-lined cylinders, the cylinder life is based upon the rate of fatigue crack growth. The ultrasonic inspection, or equivalent, of each cylinder or liner is required to ensure the absence of flaws which exceed the maximum allowable size. This approach permits the optimised design and manufacture of light weight cylinders for natural gas vehicle service. For all-composite cylinders with non-metallic non-load bearing liners the ‘safe life’ is demonstrated by appropriate design methods, design qualification testing and manufacturing controls. 2. REFERENCES The following standards contain provisions which, through reference in this text, constitute provisions of this annex (until equivalent ECE provisions will be available). ASTM Standards (1) ASTM B117-90 Test method of Salt Spray (Fog) Testing; ASTM B154-92 Mercurous Nitrate Test for Copper and Copper Alloys; ASTM D522-92 Mandrel Bend Test of attached Organic Coatings; ASTM D1308-87 Effect of Household Chemicals on Clear and Pigmented Organic Finishes; ASTM D2344-84 Test Method for Apparent interlaminar Shear Strength of Parallel Fibre Composites by Short Beam Method; ASTM D2794-92 Test Method for Resistance of Organic Coatings to the Effects of Rapid Deformation (Impact); ASTM D3170-87 Chipping Resistance of Coatings; ASTM D3418-83 Test Method for Transition Temperatures Polymers by Thermal Analysis; ASTM E647-93 Standard Test, Method for Measurement of Fatigue Crack Growth Rates; ASTM E813-89 Test Method for JIC, a Measure of Fracture Toughness; ASTM G53-93 Standard Practice for Operating Light and Water — Exposure Apparatus (Fluorescent UV-Condensation Type) for Exposure of non-metallic materials. BSI Standards (2) BS 5045 Part 1 (1982) Transportable Gas Containers — Specification for Seamless Steel Gas Containers Above 0,5 litre Water Capacity; BS 7448-91 Fracture Mechanics Toughness Tests Part I — Method for Determination of KIC, Critical COD and Critical J Values of metallic materials; BS PD 6493-1991 Guidance an Methods for Assessing the A Acceptability of Flaws in Fusion Welded Structures; Metallic Materials. ISO Standards (3) ISO 148-1983 Steel — Charpy Impact Test (v-notch); ISO 306-1987 Plastics — Thermoplastic Materials — Determination of Vicat Softening Temperature; ISO 527 Pt 1-93 Plastics — Determination of Tensile Properties — Part I: General principles; ISO 642-79 Steel-Hardenability Test by End Quenching (Jominy Test); ISO 2808-91 Paints and Varnishes — Determination of film Thickness; ISO 3628-78 Glass Reinforced Materials — Determination of Tensile Properties; ISO 4624-78 Plastics and Varnishes — Pull-off Test for adhesion; ISO 6982-84 Metallic Materials — Tensile Testing; ISO 6506-1981 Metallic Materials — Hardness test — Brinell Test; ISO 6508-1986 Metallic Materials — Hardness Tests — Rockwell Test (Scales, ABCDEFGHK); ISO 7225 Precautionary Labels for Gas Cylinders; ISO/DIS 7866-1992 Refillable Transportable Seamless Aluminium Alloy Cylinders for Worldwide Usage Design, Manufacture and Acceptance; ISO 9001:1994 Quality Assurance in Design/Development. Production, Installation and Servicing; ISO 9002:1994 Quality Assurance in Production and Installation; ISO/DIS 12737 Metallic Materials — Determination of the Plane-Strain Fracture Toughness; ISO/IEC Guide 25-1990 General requirements for the Technical Competence of Testing Laboratories; ISO/IEC Guide 48-1986 Guidelines for Third Party Assessment and Registration of Supplies Quality System; ISO/DIS 9809 Transportable Seamless Steel Gas Cylinders Design, Construction and Testing — Part I: Quenched and Tempered Steel Cylinders with Tensile Strength < 1 100 MPa; NACE Standard (4) NACE TM0177-90 Laboratory Testing of Metals for Resistance to Sulphide Stress Cracking in H2S Environments. 3. DEFINITIONS For the purpose of this annex the following definitions shall apply: 3.1. (not allocated) 3.2. auto-frettage: A pressure application procedure used in manufacturing composite cylinders with metal liners, which strains the liner past its limit of elasticity, sufficiently to cause permanent plastic deformation which results in the liner having compressive stresses and the fibres having tensile stresses at zero internal pressure. 3.3. auto-frettage pressure: The pressure within the over-wrapped cylinder at which the required distribution of stresses between the liner and the over-wrap is established. 3.4. batch — composite cylinders: A ‘batch’ shall be a group of cylinders successively produced from qualified liners having the same size, design, specified materials of construction and process of manufacture. 3.5. batch — metal cylinders and liners: A ‘batch’ shall be a group of metal cylinders or liners successively produced having the same nominal diameter, wall thickness, design, specified material of construction, process of manufacture, equipment for manufacture and heat treatment, and conditions of time, temperature and atmosphere during heat treatment. 3.6. batch non-metallic liners: A ‘batch’ shall be a group of non-metallic liners successively produced having the same nominal diameter, wall thickness, design specified material of construction and process of manufacture. 3.7. batch limits: In no case shall a ‘batch’ be permitted to exceed 200 finished cylinders or liners (not including destructive test cylinders or liners), or one shift of successive production, whichever is greater. 3.8. composite cylinder: A cylinder made of resin impregnated continuous filament wound over a metallic or non-metallic liner. Composite cylinders using non-metallic liners are referred to as all-composite cylinders. 3.9. controlled tension winding: A process used in manufacturing hoop wrapped composite cylinders with metal liners by which compressive stresses in the liner and tensile stresses in the over-wrap at zero internal pressure are obtained by winding the reinforcing filaments under significant high tension. 3.10. filling pressure: The gas pressure in the cylinder immediately upon completion of filling. 3.11. finished cylinders: Completed cylinders which are ready for use, typical of normal production, complete with identification marks and external coating including integral insulation specified by the manufacturer, but free from non-integral insulation or protection. 3.12. full-wrap: An over-wrap having a filament wound reinforcement both in the circumferential and axial direction of the cylinder. 3.13. gas temperature: The temperature of gas in a cylinder. 3.14. hoop-wrap: An over-wrap having a filament wound reinforcement in a substantially circumferential pattern over the cylindrical portion of the liner so that the filament does not carry any significant load in a direction parallel to the cylinder longitudinal axis. 3.15. liner: A container that is used as a gas-tight, inner shell, on which reinforcing fibres are filament wound to reach the necessary strength. Two types of liners are described in this standard: Metallic liners that are designed to share the load with the reinforcement, and non-metallic liners that do not carry any part of the load. 3.16. manufacturer: The person or organization responsible for the design, fabrication and testing of the cylinders. 3.17. maximum developed pressure: The settled pressure developed when gas in a cylinder filled to the working pressure is raised to the maximum service temperature. 3.18. over-wrap: The reinforcement system of filament and resin applied over the liner. 3.19. prestressing: The process of applying auto-frettage or controlled tension winding. 3.20. service life: The life in years during which the cylinders may safely be used in accordance with the standard service conditions. 3.21. settled pressure: The gas pressure when a given settled temperature is reached. 3.22. settled temperature: The uniform gas temperature after any change in temperature caused by filling has dissipated. 3.23. test pressure: The pressure at which the cylinder is hydrostatically tested. 3.24. working pressure: The settled pressure of 20 MPa at a uniform temperature of 15 °C. 4. SERVICE CONDITIONS 4.1. General 4.1.1. Standard service conditions The standard service conditions specified in this section are provided as a basis for the design, manufacture, inspection, testing, and approval of cylinders that are to be mounted permanently on vehicles and used to store natural gas at ambient temperatures for use as a fuel on vehicles. 4.1.2. Use of cylinders The service conditions specified are also intended to provide information on how cylinders made to this Regulation may safely be used to: (a) manufacturers of cylinders; (b) owners of cylinders; (c) designers or contractors responsible for the installation of cylinders; (d) designers or owners of equipment used to refuel vehicle cylinders; (e) suppliers of natural gas; and (f) regulatory authorities who have jurisdiction over cylinder use. 4.1.3. Service life The service life for which cylinders are safe shall be specified by the cylinder designer on the basis of use under service conditions specified herein. The maximum service life shall be 20 years. Periodic requalification Recommendations for periodic requalification by visual inspection or testing during the service life shall be provided by the cylinder manufacturer on the basis of use under service conditions specified herein. Each cylinder shall be visually inspected at least every 48 months after the date of its entry into service on the vehicle (vehicle registration), and at the time of any re-installation, for external damage and deterioration, including under the support straps. The visual inspection shall be performed by a competent agency approved or recognized by the Regulatory Authority, in accordance with the manufacturers specifications: Cylinders without label containing mandatory information, or with labels containing mandatory information that are illegible in any way shall be removed from service. If the cylinder can be positively identified by manufacturer and serial number, a replacement label may be applied, allowing the cylinder to remain in service. 4.1.4.1. Cylinders involved in collisions Cylinders which have been involved in a vehicle collision shall be reinspected by an agency authorized by the manufacturer, unless otherwise directed by the Authority having jurisdiction. Cylinder which have not experienced any impact damage from the collision may be returned to service, otherwise the cylinder shall be returned to the manufacturer for evaluation. 4.1.4.2. Cylinders involved in fires Cylinders which have been subject to the action of fire shall be reinspected by an agency authorized by the manufacturer, or condemned and removed from service. 4.2. Maximum pressures The cylinder pressure shall be limited to the following: (a) a pressure that would settle to 20 MPa at a settled temperature of 15 °C; (b) 26 MPa, immediately after filling, regardless of temperature; 4.3. Maximum number of filling cycles Cylinders are designed to be filled up to a settled pressure of 20 MPa bar at a settled gas temperature of 15 °C for up to 1 000 times per year of service. 4.4. Temperature range 4.4.1. Settled gas temperature Settled temperature of gas in cylinders may vary from a minimum of –40 °C to a maximum of 65 °C; 4.4.2. Cylinder temperatures The temperature of the cylinder materials may vary from a minimum of –40 °C to a maximum of +82 °C; Temperatures over +65 °C may be sufficiently local, or of short enough duration, that the temperature of gas in the cylinder never exceeds +65 °C, except under the conditions of paragraph 4.4.3; 4.4.3. Transient temperatures Developed gas temperatures during filling and discharge may vary beyond the limits of paragraph 4.4.1; 4.5. Gas composition Methanol and/or glycol shall not be deliberately added to the natural gas. Cylinder should be designed to tolerate being filled with natural gas meeting either of the following three conditions: (a) SAE J1616 (b) Dry gas Water vapour would normally be limited to less than 32 mg/m3. a pressure dewpoint of –9 °C at 20 MPa. There would be no constituent limits for dry gas, except for: — Hydrogen sulfide and other soluble sulfides: … 23 mg/m3 — Oxygen: … 1 per cent by volume Hydrogen shall be limited to 2 per cent by volume when cylinders are manufactured from a steel with an ultimate tensile strength exceeding 950 MPa; (c) Wet gas Gas that contains a water content higher than b) normally meets the following constituent limits; — Hydrogen sulfide and other soluble sulfides: … 23 mg/m3 — Oxygen: … 1 per cent by volume — Carbon dioxide: … 4 per cent by volume — Hydrogen: … 0,1 per cent by volume Under wet gas conditions, a minimum of 1 mg of compressor oil per kg of gas is necessary to protect metallic cylinders and liners. 4.6. External surfaces Cylinders are not designed for continuous exposure to mechanical or chemical attack, e.g. leakage from cargo that may be carried on vehicles or severe abrasion damage from road conditions, and shall comply with recognized installation standards. However, cylinder external surfaces may be inadvertently exposed to: (a) water, either by intermittent immersion or road spray; (b) salt, due to the operation of the vehicle near the ocean or where ice melting salt is used; (c) ultra-violet radiation from sunlight; (d) impact of gravel; (e) solvents, acids and alkalis, fertilizers; and (f) automotive fluids, including gasoline, hydraulic fluids, glycol and oils. 4.7. Gas permeation or leakage Cylinders may be located in enclosed spaces for extended periods of time. Permeation of gas through the cylinder wall or leakage between the end connections and the liner shall be considered in the design. 5. DESIGN APPROVAL 5.1. General The following information shall be submitted by the cylinder designer with a request for approval to the Competent Authority: (a) statement of service (paragraph 5.2.); (b) design data (paragraph 5.3.); (c) manufacturing data (paragraph 5.4.); (d) quality system (paragraph 5.5.); (e) fracture performance and NDE (Non Destructive Examination) defect size (paragraph 5.6.); (f) specification sheet (paragraph 5.7.); (g) additional supporting data (paragraph 5.8.); For cylinders designed in accordance with ISO 9809 it is not required to provide the stress analysis report in paragraph 5.3.2. or the information in paragraph 5.6. 5.2. Statement of service The purpose of this statement of service is to guide users and installers of cylinders as well as to inform the approving Competent Authority, or their designated representative. The statement of service shall include: (a) a statement that the cylinder design is suitable for use in the service conditions defined in paragraph 4 for the service life of the cylinder; (b) the service life; (c) the minimum in-service test and/or inspection requirements; (d) the pressure relief devices and/or insulation required; (e) support methods, protective coatings, etc., required but not provided; (f) a description of the cylinder design; (g) any other information necessary to ensure the safe use and inspection of the cylinder. 5.3. Design data 5.3.1. Drawings Drawings shall show the following as a minimum: (a) Title, reference number, date of issue, and revision numbers with dates of issue if applicable; (b) Reference to this Regulation and the cylinder type; (c) All dimensions complete with tolerances, including details of end closure shapes with minimum thicknesses and of openings; (d) Mass, complete with tolerance, of cylinders; (e) Material specifications, complete with minimum mechanical and chemical properties or tolerance ranges and, for metal cylinders or metal liners, the specified hardness range; (f) Other data such as, auto-frettage pressure range, minimum test pressure, details of the fire protection system and of the exterior protective coating. 5.3.2. Stress analysis report A finite element stress analysis or other stress analysis shall be provided; A table summarizing the calculated stresses in the report shall be provided. 5.3.3. Material test data A detailed description of the materials and tolerances of the materials properties used in the design shall be provided. Test data shall also be presented characterizing the mechanical properties and the suitability of the materials for service under the conditions specified in paragraph 4. 5.3.4. Design qualification test data The cylinder material, design, manufacture and examination shall be provided to be adequate for their intended service by meeting the requirements of the tests required for the particular cylinder design, when tested in accordance with the relevant methods of test detailed in appendix A to this annex. The test data shall also document the dimensions, wall thicknesses and weights of each of the test cylinders. 5.3.5. Fire protection The arrangement of pressure relief devices that will protect the cylinder from sudden rupture when exposed to the fire conditions in paragraph A.15 shall be specified. Test data shall substantiate the effectiveness of the specified fire protection system. 5.3.6. Cylinder supports Details of cylinder supports or support requirements shall be provided in accordance with paragraph 6.11. 5.4. Manufacturing data Details of all fabrication processes, non-destructive examinations, production tests and batch tests Shall be provided; The tolerances for all production processes such as heat treatment, end forming, resin mix ratio, filament winding tension and speed, curing times and temperatures, and auto-frettage procedures shall be specified; Surface finish, thread details, acceptance criteria for ultrasonic scanning (or equivalent), and maximum lot sizes for batch tests shall also be specified. 5.5. (not allocated) 5.6. Fracture performance and NDE defect size 5.6.1. Fracture performance The manufacturer shall demonstrate the Leak-Before-Break performance of the design as described in paragraph 6.7. 5.6.2. NDE defect size Using the approach described in paragraph 6.15.2 the manufacturer shall establish the maximum defect size for non-destructive examination which will prevent the failure of the cylinder during its service life due to fatigue, or failure of the cylinder by rupture. 5.7. Specification sheet A summary of the documents providing the information required in paragraph 5.1. shall be listed on a specification sheet for each cylinder design. The title, reference number, revision numbers and dates of original issue and version issues of each document shall be given. All documents shall be signed or initialled by the issuer; The specification sheet shall be given a number, and revision numbers if applicable, that can be used to designate the cylinder design and shall carry the signature of the engineer responsible for the design. Space shall be provided on the specification sheet for a stamp indicating registration of the design. 5.8. Additional supporting data Additional data which would support the application, such as the service history of material proposed for use, or the use of a particular cylinder design in other service conditions, shall be provided where applicable. 5.9. Approval and certification 5.9.1. Inspection and testing Evaluation of conformity is required to be performed in accordance with the provisions of paragraph 9 of this Regulation; In order to ensure that the cylinders are in compliance with this international Regulation they shall be subject to inspection in accordance with paragraphs 6.13. and 6.14. performed by the Competent Authority. 5.9.2. Test certificate If the results of prototype testing according to paragraph 6.13. are satisfactory, the Competent Authority shall issue a test certificate. An example of a test certificate is given in Appendix D to this annex. 5.9.3. Batch acceptance certificate The Competent Authority shall prepare an acceptance certificate as provided in appendix D to this annex. 6. REQUIREMENTS APPLICABLE TO ALL CYLINDER TYPES 6.1. General The following requirements are generally applicable to the cylinder types specified in paragraphs 7 to 10. The design of cylinders shall cover all relevant aspects which are necessary to ensure that every cylinder produced according to the design is fit for its purpose for the specified service life; Type CNG-1 steel cylinders designed in accordance with ISO 9809 and meeting all the requirements therein are only required to meet the requirements of paragraphs 6.3.2.4. and 6.9 to 6.13. 6.2. Design This Regulation does not provide design formulas nor permissible stresses or strains, but requires the adequacy of the design to be established by appropriate calculations and demonstrated by cylinders being capable of consistently passing the materials, design qualification, production and batch tests specified in this Regulation; All designs shall ensure a ‘leakage before break’ failure mode under feasible degradation of pressure parts during normal service. If leakage of metal cylinders or metal liners occurs, it shall be only by the growth of a fatigue crack. 6.3. Materials 6.3.1. Materials used shall be suitable for the service conditions specified in paragraph 4. The design shall not have incompatible materials in contact. The design qualification tests for materials are summarised in table 6.1. Steel 6.3.2.1. Composition Steels shall be aluminium and/or silicon killed and produced to predominantly fine grain practice. The chemical composition of all steels shall be declared and defined at least by: (a) carbon, manganese, aluminium and silicon contents in all cases; (b) nickel, chromium, molybdenum, boron and vanadium contents, and any other alloying elements intentionally added. The following limits shall not be exceeded in the cast analysis: Tensile strength < 950 MPa ≥ 950 MPa Sulfur 0,020 per cent 0,010 per cent Phosphorus 0,020 per cent 0,020 per cent Sulfur and Phosphorus 0,030 per cent 0,025 per cent When a carbon-boron steel is used, a hardenability test in accordance with ISO 642, shall be performed on the first and last ingot or slab of each heat of steel. The hardness as measured in a distance of 7,9 mm from the quenched end, shall be within the range 33-53 HRC, or 327-560 HV, and shall be certified by the material manufacturer; 6.3.2.2. Tensile properties The mechanical properties of the steel in the finished cylinder or liner shall be determined in accordance with paragraph A.1 (appendix A). The elongation for steel shall be at least 14 per cent. 6.3.2.3. Impact properties The impact properties of the steel in the finished cylinder or liner shall be determined in accordance with paragraph A.2 (appendix A). Impact values shall not be less than that indicated in table 6.2 of this annex. 6.3.2.4. Sulfide stress cracking resistance If the upper limit of the specified tensile strength for the steel exceeds 950 MPa, the steel from a finished cylinder shall be subjected to a sulphide stress cracking resistance test in accordance with appendix A to this annex, item A.3., and meet the requirements listed therein. Aluminium 6.3.3.1. Composition Aluminium alloys shall be quoted in line with Aluminium Association practice for a given alloy system. The impurity limits for lead and bismuth in any aluminium alloy shall not exceed 0,003 per cent. 6.3.3.2. Corrosion tests Aluminium alloys shall meet the requirements of the corrosion tests carried out in accordance with paragraph A.4 (appendix A). 6.3.3.3. Sustained load cracking Aluminium alloys shall meet the requirements of the sustained load cracking tests carried out in accordance with paragraph A.5 (appendix A). 6.3.3.4. Tensile properties The mechanical properties of the aluminium alloy in the finished cylinder shall be determined in accordance with paragraph A.l (appendix A). The elongation for aluminium shall be at least 12 per cent. Resins 6.3.4.1. General The material for impregnation may be thermosetting or thermoplastic resins. Examples of suitable matrix materials are epoxy, modified epoxy, polyester and vinylester thermosetting plastics, and polyethylene and polyamide thermoplastic material. 6.3.4.2. Shear strength Resin materials shall be tested in accordance with paragraph A.26 (appendix A), and meet the requirements therein. 6.3.4.3. Glass transition temperature The glass transition temperature of the resin material shall be determined in accordance with ASTM D3418. 6.3.5. Fibres Structural reinforcing filament material types shall be glass fibre, aramid fibre or carbon fibre. If carbon fibre reinforcement is used the design shall incorporate means to prevent galvanic corrosion of metallic components of the cylinder. The manufacturer shall keep on file the published specifications for composite materials, the material manufacturer's recommendations for storage, conditions and shelf life and the material manufacturer's certification that each shipment conforms to said specification requirements. The fibre manufacturer shall certify that the fibre material properties conform to the manufacturer's specifications for the product. 6.3.6. Plastic liners The tensile yield strength and ultimate elongation shall be determined in accordance with paragraph A.22 (appendix A). Tests shall demonstrate the ductile properties of the plastic liner material at temperatures of –50 °C or lower by meeting the values specified by the manufacturer; The polymeric material shall be compatible with the service conditions specified in paragraph 4 of this annex. In accordance with the method described in paragraph A.23 (appendix A), the softening temperature shall be at least 90 °C, and the melting temperature at least 100 °C. 6.4. Test pressure The minimum test pressure used in manufacture shall be 30 MPa. 6.5. Burst pressures and fibre stress ratios For all types of cylinder the minimum actual burst pressure shall not be less than the values given in table 6.3 of this annex. For type CNG-2, CNG-3 and CNG-4 designs the composite over-wrap shall be designed for high reliability under sustained loading and cyclic loading. This reliability shall be achieved by meeting or exceeding the composite reinforcement stress ratio values given in table 6.3 of this annex. Stress ratio is defined as the stress in the fibre at the specified minimum burst pressure divided by the stress in the fibre at working pressure. The burst ratio is defined as the actual burst pressure of the cylinder divided by the working pressure; For type CNG-4 designs, the stress ratio is equal to the burst ratio; For type CNG-2 and CNG-3 designs (metal-lined, composite over-wrapped) stress ratio calculations must include: (a) An analysis method with capability for non-linear materials (special purpose computer program or finite element analysis program); (b) Elastic-plastic stress-strain curve for liner material must be known and correctly modelled; (c) Mechanical properties of composite materials must be correctly modelled; (d) Calculations must be made at: auto-frettage, zero after auto-frettage, working and minimum burst pressures; (e) Prestresses from winding tension must be accounted for in the analysis; (f) Minimum burst pressure must be chosen such that the calculated stress at minimum burst pressure divided by the calculated stress at working pressure meets the stress ratio requirements for the fibre used; (g) When analyzing cylinders with hybrid reinforcement (two or more different fibre types), the load share between the different fibres must be considered based on the different elastic modulii of the fibres. The stress ratio requirements for each individual fibre type must be in accordance with the values given in table 6.3 of this annex. Verification of the stress ratios may also be performed using strain gauges. An acceptable method is outlined in the informative appendix E to this annex. 6.6. Stress analysis A stress analysis shall be performed to justify the minimum design wall thicknesses. It shall include the determination of the stresses in liners and fibres of composite designs. 6.7. Leak-before-break (LBB) assessment Types CNG-1, CNG-2 and CNG-3 cylinders shall demonstrate Leak-Before-Break (LBB) performance. The LBB performance test shall be carried out in accordance with paragraph A.6 (appendix A). Demonstration of LBB performance is not required for cylinder designs that provide a fatigue life exceeding 45 000 pressure cycles when tested in accordance with paragraph A.13 (appendix A). Two methods of LBB assessment are included for information in appendix F to this annex. 6.8. Inspection and testing The manufacturing inspection shall specify programmes and procedures for: (a) manufacturing inspection, tests and acceptance criteria; and (b) periodic in service inspection, tests and acceptance criteria. The interval of visual reinspection of the external cylinder surfaces shall be in accordance with paragraph 4.1.4. of this annex unless varied by the Competent Authority. The manufacturer shall establish the visual reinspection rejection criteria based on the results of pressure cycling tests performed on cylinders containing flaws. A guide for manufacturer's instructions for handling, use and inspection is provided in appendix G to this annex. 6.9. Fire protection All cylinders shall be protected from fire with pressure relief devices. The cylinder, its materials, pressure relief devices and any added insulation or protective material shall be designed collectively to ensure adequate safety during fire conditions in the test specified in paragraph A.15 (appendix A). Pressure relief devices shall be tested in accordance with paragraph A.24 (appendix A). 6.10. Openings 6.10.1. General Openings are permitted in heads only. Centre line of openings shall coincide with the longitudinal axis of the cylinder. Threads shall be clean cut, even, without surface discontinuities, and to gauge. 6.11. Cylinder supports The manufacturer shall specify the means by which cylinders shall be supported for installation on vehicles. The manufacturer shall also supply support installation instructions, including clamping force and torque to provide the required restraining force but not cause unacceptable stress in the cylinder or damage to the cylinder surface. 6.12. Exterior environmental protection The exterior of cylinders shall meet the requirements of the environmental test conditions of paragraph A.14 (appendix A). Exterior protection may be provided by using any of the following: (a) a surface finish giving adequate protection (e.g. metal sprayed on aluminium, anodizing); or (b) the use of a suitable fibre and matrix material (e.g. carbon fibre in resin); or (c) a protective coating (e.g. organic coating, paint) that shall meet the requirements of paragraph A.9 (appendix A). Any coatings applied to cylinders shall be such that the application process does not adversely affect the mechanical properties of the cylinder. The coating shall be designed to facilitate subsequent in service inspection and the manufacturer shall provide guidance on coating treatment during such inspection to ensure the continued integrity of the cylinder. Manufacturers are advised that an environmental performance test that evaluates the suitability of coating systems is provided in the informative appendix H to this annex. 6.13. Design qualification tests For the approval of each cylinder type the material, design, manufacture and examination shall be proved to be adequate for their intended service by meeting the appropriate requirements of the material qualification tests summarized in table 6.1 of this annex and the cylinder qualification tests summarized in table 6.4 of this annex, with all tests in accordance with the relevant methods of test as described in appendix A to this annex. The test cylinders or liners shall be selected and the tests witnessed by the Competent Authority. If more cylinders or liners are subjected to the tests than are required by this annex, all results shall be documented. 6.14. Batch tests The batch tests specified in this annex for each cylinder type shall be conducted on cylinders or liners taken from each batch of finished cylinders or liners. Heat treated witness samples shown to be representative of finished cylinders or liners may also be used. Batch tests required for each cylinder type are specified in table 6.5 of this annex. 6.15. Production examinations and tests 6.15.1. General Production examinations and tests shall be carried out on all cylinders produced in a batch. Each cylinder shall be examined during manufacture and after completion by the following means: (a) ultrasonic scanning (or demonstrated equivalent) of metallic cylinders and liners in accordance with BS 5045, Part 1, annex B, or demonstrated equivalent method, to confirm that the maximum defect size present is smaller than the size specified in the design; (b) verification that the critical dimensions and mass of the completed cylinder and of any liner and over-wrapping are within design tolerances; (c) verification of compliance with specified surface finish with special attention to deep drawn surfaces and folds or laps in the neck or shoulder of forged or spun end enclosures or openings; (d) verification of markings; (e) hardness tests of metallic cylinders and liners in accordance with paragraph A.8 (appendix A) shall be carried out after the final heat treatment and the values thus determined shall be in the range specified for the design; (f) hydrostatic proof test in accordance with paragraph A.11 (appendix A); A summary of critical production inspection requirements to be performed on every cylinder is provided in table 6.6 of this annex. 6.15.2. Maximum defect size For type CNG-1, CNG-2 and CNG-3 designs, the maximum defect size at any location in the metal cylinder or metal liner that will not grow to a critical size within the specified service life shall be determined. The critical defect size is defined as the limiting through-wall (cylinder or liner) thickness defect that would allow stored gas to be discharged without rupturing the cylinder. Defect sizes for the rejection criteria for ultrasonic scanning, or equivalent shall be smaller than the maximum allowable defect sizes. For type CNG-2 and CNG-3 designs assume that there shall be no damage to composite due to any time-dependent mechanisms; The allowable defect size for NDE shall be determined by an appropriate method. Two such methods are outlined in the informative appendix F to this annex. 6.16. Failure to meet test requirements In the event of failure to meet test requirements retesting or reheat treatment and retesting shall be carried out as follows: (a) if there is evidence of a fault in carrying out a test, or an error of measurement, a further test shall be performed. If the result of this test is satisfactory, the first test shall be ignored; (b) If the test has been carried out in a satisfactory manner, the cause of test failure shall be identified. If the failure is considered to be due to the heat treatment applied, the manufacturer may subject all the cylinders of the batch to a further heat treatment. If the failure is not due to the heat treatment applied, all the identified defective cylinders shall be rejected or repaired by an approved method. The non-rejected cylinders are then considered as a new batch. In both cases the new batch shall be retested. All the relevant prototype or batch tests needed to prove the acceptability of the new batch shall be performed again. If one or more tests prove even partially unsatisfactory, all cylinders of the batch shall be rejected. 6.17. Change of design A design change is any change in the selection of structural materials or dimensional change not attributable to normal manufacturing tolerances. Minor design changes shall be permitted to be qualified through a reduced test program. Changes of design specified in table 6.7 shall require design qualification testing as specified in the table. Table 6.1 Material design qualification test Relevant paragraph of this annex Steel Aluminium Resins Fibres Plastic liners Tensile properties 6.3.2.2 6.3.3.4 6.3.5 6.3.6 Sulfide stress cracking resistance 6.3.2.4 Impact properties 6.3.2.3 Sustained load cracking resistance 6.3.3.3 Stress corrosion cracking 6.3.3.2 Shear strength 6.3.4.2 Glass transition temperature 6.3.4.3 Softening/Melting temperature 6.3.6 Fracture mechanics (5) 6.7 6.7

Table 6.2 Impact test acceptable values Cylinder diameter D, mm > 140 ≤ 140 Direction of testing transverse longitudinal Width of test piece, mm 3-5 > 5-7,5 > 7,5-10 3 to 5 Test temperature, °C –50 –50 Mean of 3 specimens 30 35 40 60 Impact strength, J/cm2 Individual specimen 24 28 32 48

Table 6.3 Minimum actual burst values and stress ratios CNG-1 All-metal CNG-2 Hoop-wrapped CNG-3 Fully-wrapped CNG-4 All-composite Burst pressure [MPa] Stress ratio [MPa] Burst pressure [MPa] Stress ratio [MPa] Burst pressure [MPa] Stress ratio [MPa] Burst pressure [MPa] All metal 45 Glass 2,75 50 1) 3,65 70 1) 3,65 73 Aramid 2,35 47 3,10 60 1) 3,1 62 Carbon 2,35 47 2,35 47 2,35 47 Hybrid 2) 2) 2) Note 1: Minimum actual burst pressure. In addition, calculations must be performed in accordance with paragraph 6.5. of this annex to confirm that the minimum stress ratio requirements are also met. Note 2: Stress ratios and burst pressures shall be calculated in accordance with paragraph 6.5. of this annex. Table 6.4 Cylinder design qualification tests Test and annex reference Cylinder type CNG-1 CNG-2 CNG-3 CNG-4 A.12 Burst X (6) X X X A.13 Ambient temp/cycle X (6) X X X A.14 Acid environment test X X X A.15 Bonfire X X X X A.16 Penetration X X X X A.17 Flaw tolerance X X X A.18 High temp. creep X X X A.19 Stress rupture X X X A.20 Drop test X X A.21 Permeation X A.24 PRD performance X X X X A.25 Boss torque test X A.27 Natural gas cycling X A.6 LBB assesment X X X A.7 Extreme temperature/cycle X X X X = required

Table 6.5 Batch tests Test and annex reference Cylinder type CNG-1 CNG-2 CNG-3 CNG-4 A.12 Burst X X X X A.13 Ambient cycle X X X X A.1 Tensile X X (8) X (8) A.2 Impact (steel) X X (8) X (8) A.9.2 Coating (7) X X X X X = required

Table 6.6 Critical production inspection requirements Type CNG-1 CNG-2 CNG-3 CNG-4 Inspection requirement Critical dimensions X X X X Surface finish X X X X Flaws (ultrasonic or equivalent) X X X Hardness of metal cylinders and metal liners X X X Hydrostatic proof test X X X X Leak test X Markings X X X X X = required

Table 6.7 Change of design Type of test Design change Burst Hydrostatic A.12 Cycling ambient temp A.13 Environmental A.14 Bonfire A.15 Flaw tolerance A.17 Penetration A.16 Stress rupture A.19 High. temp: Creep A.18 Drop test A.20 Boss torque A.25 Permeation A.21 CNG Cycling A.27 PRD performance A.24 Fibre manufacturer X X X (9) X (10) Metallic cylinder or liner material X X X (9) X X (9) X X (9) Plastic liner material X X X (10) Fibre material X X X X X X X X (10) Resin material X X X X Diameter change ≤ 20 per cent X X Diameter change > 20 per cent X X X X (9) X Length change ≤ 50 per cent X X (11) Length change > 50 per cent X X X (11) Working pressure change ≤ 20 per cent @ X X Dome shape X X X (10) Opening size X X Coating change X End boss design X (10) Change in manuf. process X X Pressure relief device X X X = required @ = Only when thickness change proportional to diameter and/or pressure change 7. TYPE CNG-1 METAL CYLINDERS 7.1. General The design shall identify the maximum size of an allowable defect at any point in the cylinder which will not grow to a critical size within the specified retest period, or service life if no retest is specified, of a cylinder operating to the working pressure. Determination of leak-before-break (LBB) performance shall be done in accordance with the appropriate procedures defined in paragraph A.6 (appendix A). Allowable defect size shall be determined in accordance with paragraph 6.15.2. above. Cylinders designed in accordance with ISO 9809 and meeting all the requirements therein are only required to meet the materials test requirements of paragraph 6.3.2.4. above and the design qualification test requirements of paragraph 7.5., except paragraphs 7.5.2. and 7.5.3. below. 7.2. Stress analysis The stresses in the cylinder shall be calculated for 2 MPa, 20 MPa, test pressure and design burst pressure. The calculations shall use suitable analysis techniques using thin-shell theory that takes into account out-of-plane bending of the shell to establish stress distributions at the neck, transition regions and the cylindrical part of the cylinder. 7.3. Manufacturing and production test requirements 7.3.1. General The ends of aluminium cylinders shall not be closed by a forming process. The base ends of steel cylinders which have been closed by forming, except those cylinders designed in accordance with ISO 9809, shall be NDE inspected or equivalent. Metal shall not be added in the process of closure at the end. Each cylinder shall be examined before end forming operations for thickness and surface finish. After end forming the cylinders shall be heat treated to the hardness range specified for the design. Localized heat treatment is not permitted. When a neck ring, foot ring or attachments for support are provided, it shall be of material compatible with that of the cylinder and shall be securely attached by a method other than welding, brazing or soldering. 7.3.2. Non-destructive examination The following tests shall be carried out on each metallic cylinder: (a) Hardness test in accordance with paragraph A.8 (appendix A), (b) Ultrasonic examination, in accordance with BS 5045, Part 1, annex I, or demonstrated equivalent NDT method, to ensure that the maximum defect size does not exceed the size specified in the design as determined in accordance with paragraph 6.15.2. above. 7.3.3. Hydrostatic pressure testing Each finished cylinder shall be hydrostatically pressure tested in accordance with paragraph A.11 (appendix A). 7.4. Cylinder batch tests Batch testing shall be conducted on finished cylinders which are representative of normal production and are complete with identification marks. Two cylinders shall be randomly selected from each batch. If more cylinders are subjected to the tests than are required by this annex, all results shall be documented. The following tests shall as a minimum be carried out on these. (a) Batch materials tests. One cylinder, or a heat treat witness sample representative of a finished cylinder, shall be subjected to the following tests: (i) Critical dimensions checked against the design; (ii) One tensile test in accordance with paragraph A.1 (appendix A) and meet the requirements of the design; (iii) For steel cylinders, three impact tests in accordance with paragraph A.2 (appendix A) and meet the requirements of paragraph 6.3.2.3. above; (iv) When a protective coating is a part of the design, the coating shall be tested in accordance with paragraph A.9.2 (appendix A); All cylinders represented by a batch test which fail to meet the specified requirements shall follow the procedures specified in paragraph 6.16. above. Where the coating fails to meet the requirements of paragraph A.9.2 (appendix A), the batch shall be 100 per cent inspected to remove similarly defective cylinders. The coating on all defective cylinders may be stripped and recoated. The coating batch test shall then be repeated; (b) Batch burst test. One cylinder shall be hydrostatically pressurized to burst in accordance with paragraph A.12 (appendix A). If the burst pressure is less than the minimum calculated burst pressure the procedures specified in paragraph 6.16. above shall be followed. (c) Periodic pressure cycling test. Finished cylinders shall be pressure cycled in accordance with paragraph A.13 (appendix A) at a test frequency defined as follows: (i) one cylinder from each batch shall be pressure cycled for a total of 1 000 times the specified service life in years, with a minimum 15 000 cycles; (ii) on 10 sequential production batches of a design family (i.e. similar materials and processes), should none of the pressure cycled cylinders in (i) above leak or rupture in less than 1 500 cycles times the specified life in years (minimum 22 500 cycles) then the pressure cycle test can be reduced to one cylinder from every 5 batches of production; (iii) on 10 sequential production batches of a design family, should none of the pressure cycled cylinders in (i) above leak or rapture in less than 2 000 cycles times the specified service life in years (minimum 30 000 cycles) then the pressure cycle test can be reduced to one cylinder from every 10 batches of production; (iv) should more than 6 months have expired since the last batch of production. then a cylinder from the next batch of production shall be pressure cycle tested in order to maintain the reduced frequency of batch testing in (ii) or (iii) above. (v) should any reduced frequency pressure cycle test cylinder in (ii) or (iii) above fail to meet the required number of pressure cycles (minimum 22 500 or 30 000 pressure cycles, respectively, ) then it shall be necessary to repeat the batch pressure cycle test frequency in (i) for a minimum 10 production batches in order to re-establish the reduced frequency of batch pressure cycle testing in (ii) or (iii) above. (vi) should any cylinder in (i), (ii), or (iii) above fail to meet the minimum cycle life requirement of 1 000 cycles times the specified service life in years (minimum 15 000 cycles), then the cause of failure shall be determined and corrected following the procedures in paragraph 6.16. The pressure cycle test shall then be repeated on an additional three cylinders from that batch. Should any of the three additional cylinders fail to meet the minimum pressure cycling requirement of 1 000 cycles times the specified service life in years, then the batch shall be rejected. 7.5. Cylinder design qualification tests 7.5.1. General Qualification testing shall be conducted on finished cylinders which are representative of normal production and complete with identification marks. Selection, witnessing and documentation of the results shall be in accordance with paragraph 6.13. above. 7.5.2. Hydrostatic pressure burst test Three representative cylinders shall be hydrostatically pressurised to failure in accordance with paragraph A.12. (appendix A to this annex). The cylinder burst pressures shall exceed the minimum burst pressure calculated by the stress analysis for the design, and shall be at least 45 MPa. 7.5.3. Ambient temperature pressure cycling test. Two finished cylinders shall be pressure cycled at ambient temperature in accordance with paragraph A.13 (appendix A) to failure, or to a minimum of 45 000 cycles. The cylinders shall not fail before reaching the specified service life in years times 1 000 cycles. Cylinders exceeding 1 000 cycles times the specified service life in years shall fail by leakage and not by rupture. Cylinders which do not fail within 45 000 cycles shall be destroyed either by continuing the cycling until failure occurs, or by hydrostatically pressurising to burst. The number of cycles to failure and the location of the failure initiation shall be recorded. 7.5.4. Bonfire test Tests shall be conducted in accordance with paragraph A.15 (appendix A) and meet the requirements therein. 7.5.5. Penetration test Test shall be conducted in accordance with paragraph A.16 (appendix A) and meet the requirements therein. 7.5.6. LBB performance For cylinder designs not exceeding 45 000 cycles when tested as per paragraph 7.5.3. above, LBB performance tests shall be conducted in accordance with A.6 and meet the requirements therein. 8. TYPE CNG-2 HOOP-WRAPPED CYLINDERS 8.1. General During pressurisation, this type of cylinder design has a behaviour in which the displacements of the composite over-wrap and the metal liner are linearly superimposed. Due to different techniques of manufacture, this annex does not give a definite method for design. Determination of the leak-before-break (LBB) performance shall be in accordance with the appropriate procedures defined in paragraph A.6 (appendix A). Allowable defect size shall be determined in accordance with paragraph 6.15.2. above. 8.2. Design requirements 8.2.1. Metal liner The metal liner shall have a minimum actual burst pressure of 26 MPa. 8.2.2. Composite over-wrap The tensile stress in the fibres shall meet the requirements of paragraph 6.5. above. 8.2.3. Stress analysis The stresses in the composite and in the liner after prestress shall be calculated. The pressures used for these calculations shall be zero, 2 MPa, 20 MPa test pressure and design burst pressure. The calculations shall use suitable analysis techniques using thin-shell theory taking account of non-linear material behaviour of the liner to establish stress distributions at the neck, transition regions and the cylindrical part of the liner. For designs using auto-frettage to provide prestress, the limits within which the auto-frettage pressure must fall shall be calculated. For designs using controlled tension winding to provide prestress, the temperature at which it is performed, the tension required in each layer of composite and the consequent prestress in the liner shall be calculated. 8.3. Manufacturing requirements 8.3.1. General The composite cylinder shall be fabricated from a liner over-wrapped with continuous filament windings. Filament winding operations shall be computer or mechanically controlled. The filaments shall be applied under controlled tension during winding. After winding is complete, thermosetting resins shall be cured by heating, using a predetermined and controlled time-temperature profile. 8.3.2. Liner The manufacture of a metallic liner shall meet the requirements given under paragraph 7.3. above for the appropriate type of liner construction. Over-wrap The cylinders shall be fabricated in a filament winding machine. During winding the significant variables shall be monitored within specified tolerances, and documented in a winding record. These variables can include but are not limited to: (a) fibre type including sizing; (b) manner of impregnation; (c) winding tension; (d) winding speed; (e) number of rovings; (f) band width; (g) type of resin and composition; (h) temperature of the resin; (i) temperature of the liner. 8.3.3.1. Curing of thermosetting resins If a thermosetting resin is used, the resin shall be cured after filament winding. During the curing, the curing cycle (i.e. the time-temperature history) shall be documented. The curing temperature shall be controlled and shall not affect the material properties of the liner. The maximum curing temperature for cylinders with aluminium liners is 177 °C. 8.3.4. Auto-frettage Auto-frettage, if used, shall be carried out before the hydrostatic pressure test. The auto-frettage pressure shall be within the limits established in paragraph 8.2.3. above, and the manufacturer shall establish the method to verify the appropriate pressure. 8.4. Production test requirements 8.4.1. Non-destructive examination Non-destructive examinations shall be carried out in accordance with a recognized ISO or an equivalent standard. The following tests shall be carried out on each metallic liner: (a) Hardness test in accordance with paragraph A.8 (appendix A); (b) Ultrasonic examination, in accordance with BS 5045, Part 1, annex 1B, or demonstrated equivalent NDT method, to ensure that the maximum defect size does not exceed the size specified in the design. 8.4.2. Hydrostatic pressure testing Each finished cylinder shall be hydrostatically pressure tested in accordance with paragraph A.11 (appendix A). The manufacturer shall define the appropriate limit of permanent volumetric expansion for the test pressure used, but in no case shall the permanent expansion exceed 5per cent of the total volumetric expansion at test pressure. Any cylinders not meeting the defined rejection limit shall be rejected and either destroyed or used for batch rest purposes. 8.5. Cylinder batch tests 8.5.1. General Batch testing shall be conducted on finished cylinders which are representative of normal production and are complete with identification marks. Two cylinders, or a cylinder and a liner as appropriate, shall be randomly selected from each batch. If more cylinders are subjected to the tests than are required by this annex, all results shall be documented. The following tests shall as a minimum be carried out on these. Where defects are detected in over-wrapping before any auto-frettage or hydrostatic pressure testing, the over-wrapping may be completely removed and replaced; (a) Batch materials tests. One cylinder, or liner, or heat treat witness sample that is representative of a finished cylinder, shall be subjected to the following tests: (i) Dimensions checked against the design; (ii) One tensile test in accordance with paragraph A.1 (appendix A) and meet the requirements of the design; (iii) For steel liners, three impact tests in accordance with paragraph A.2 (appendix A) and meet the requirements of the design; (iv) When a protective coating is a part of the design, the coating shall be tested in accordance with paragraph A.9.2 (appendix A) and meet the requirements therein. All cylinders or liners represented by a batch test which fails to meet the requirements specified shall follow the procedures specified in paragraph 6.16. above. Where the coating fails to meet the requirements of paragraph A.9.2. (appendix A), the batch shall be 100 per cent inspected to remove similarly defective cylinders. The coating on all defective cylinders may be stripped using a method that does not affect the integrity of the composite wrapping, and recoated. The coating batch test shall then be repeated. (b) Batch burst test. One cylinder shall be tested in accordance with the requirements of paragraph 7.4(b) above; (c) Periodic pressure cycling test. In accordance with the requirements of paragraph 7.4(c) above. 8.6. Cylinder design qualification tests 8.6.1. General Qualification testing shall be conducted on cylinders which are representative of normal production and complete with identification marks. Selection, witnessing and documentation of the results shall comply with paragraph 6.13. above. 8.6.2. Hydrostatic pressure burst test (a) One liner shall be hydrostatically burst in accordance with paragraph A.12. (appendix A). The burst pressure shall exceed the minimum burst pressure specified for the liner design; (b) Three cylinders shall be hydrostatically burst in accordance with paragraph A.12 (appendix A). Cylinder burst pressures shall exceed the specified minimum burst pressure established by the stress analysis for the design, in accordance with table 6.3, and in no case less than the value necessary to meet the stress ratio requirements of paragraph 6.5 above. 8.6.3. Ambient temperature pressure cycling test Two finished cylinders shall be pressure cycle tested at ambient temperature in accordance with paragraph A.13 (appendix A) to failure, or to a minimum of 45 000 cycles. The cylinders shall not fail before reaching the specified service life in years times 1 000 cycles. Cylinders exceeding 1 000 cycles times the specified service life in years shall fail by leakage and not by rupture. Cylinders which do not fail within 45 000 cycles shall be destroyed either by continuing the cycling until failure occurs, or by hydrostatically pressurizing to burst. Cylinders exceeding 45 000 cycles are permitted to fail by rupture. The number of cycles to failure and the location of the failure initiation shall be recorded. 8.6.4. Acid environment test One cylinder shall be tested in accordance with paragraph A.14 (appendix A) and meet the requirements therein. An optional environmental test is included in the informative appendix H to this annex. 8.6.5. Bonfire test Finished cylinders shall be tested in accordance with paragraph A.15 (appendix A) and meet the requirements therein. 8.6.6. Penetration test One finished cylinder shall be tested in accordance with paragraph A.16 (appendix A) and meet the requirem