AS/NZS 2739:2003

1 - AS/NZS 2739:2003 NATURAL GAS (CNG) FUEL SYSTEMS FOR VEHICLE ENGINES
4 - PREFACE
5 - CONTENTS
7 - SECTION 1 SCOPE AND GENERAL
7 - 1.1 SCOPE
7 - 1.2 OBJECTIVE
7 - 1.3 REFERENCED DOCUMENTS
7 - 1.4 DEFINITIONS
7 - 1.4.1 Approved, approval
7 - 1.4.2 Authority
7 - 1.4.3 Authorized person
8 - 1.4.4 Automatic fuel shut-off device
8 - 1.4.5 Capacity (of a cylinder)
8 - 1.4.6 Certified kit
8 - 1.4.7 CNG (Compressed natural gas)
8 - 1.4.8 Cylinder
8 - 1.4.9 Cylinder compartment
8 - 1.4.10 Cylinder sub-compartment
8 - 1.4.11 Design pressure
8 - 1.4.12 Fuel
8 - 1.4.13 Fuel metering system
8 - 1.4.14 Fuel service line
8 - 1.4.15 Gas air mixer
9 - 1.4.16 Ignition source
9 - 1.4.17 Licensed installer
9 - 1.4.18 May
9 - 1.4.19 NGV
9 - 1.4.20 Non-return valve
9 - 1.4.21 Pressure
9 - 1.4.22 Pressure relief device
9 - 1.4.23 Professional engineer
9 - 1.4.24 Rated working pressure
9 - 1.4.25 Refuelling interlock device
9 - 1.4.26 Regulator
9 - 1.4.27 Removable cylinder
10 - 1.4.28 Shall
10 - 1.4.29 Should
10 - 1.5 NEW DESIGNS AND INNOVATIONS
10 - 1.6 VEHICLE MODIFICATIONS
11 - 1.7 MINOR ALTERATIONS
11 - 1.8 ENGINE MANAGEMENT SYSTEM ALTERATIONS
11 - 1.9 EXHAUST EMISSION REQUIREMENT (Australia only)
11 - 1.9.1 Original equipment manufacture (OEM) CNG vehicles
11 - 1.9.2 Vehicles retrofitted to CNG
11 - 1.10 APPROVED EQUIPMENT
11 - 1.11 PREVIOUSLY USED EQUIPMENT
11 - 1.11.1 Provisions
12 - 1.11.2 Prohibitions
12 - 1.12 WORKING AREA AND SAFE PRACTICES
13 - SECTION 2 COMPONENTS
13 - 2.1 GENERAL SUITABILITY
13 - 2.1.1 General
13 - 2.1.2 Suitability for pressure
13 - 2.1.3 Suitability for installation
13 - 2.2 COMPONENT PARTS
13 - 2.3 MODIFICATION
14 - SECTION 3 FUEL SYSTEM COMPONENTS
14 - 3.1 APPLICATION
14 - 3.1.1 General
14 - 3.1.2 Fuel supply system components
14 - 3.1.3 Use of multiple components
14 - 3.2 CYLINDER
14 - 3.2.1 General
14 - 3.2.2 Use of removable cylinders
14 - 3.2.3 Cylinder painting
14 - 3.3 COMPONENTS FOR REMOVABLE CYLINDERS
15 - 3.4 CYLINDER VALVE
15 - 3.5 REFUELLING CONNECTION
15 - 3.5.1 Design of connection
15 - 3.5.2 Dust cap
15 - 3.5.3 Refuelling interlock device (New Zealand only)
15 - 3.6 REFUELLING NON-RETURN VALVE
15 - 3.7 LOCATION OF REFUELLING CONNECTION
16 - 3.8 REFUELLING INFORMATION PLATE
16 - 3.9 SERVICE ISOLATION VALVE
17 - 3.10 FUEL FILTER
17 - 3.11 AUTOMATIC FUEL SHUT-OFF DEVICE
17 - 3.12 FUEL FLOW REGULATION DEVICE
17 - 3.13 CONTENTS INDICATOR
17 - 3.14 CYLINDER COMPARTMENTS AND SUB-COMPARTMENTS
17 - 3.14.1 Internal cylinders
18 - 3.14.2 Safety device discharge
18 - 3.14.3 Construction
18 - 3.14.4 Ventilation
19 - 3.14.5 Conduits
20 - 3.15 MOUNTING OF FUEL CYLINDER
20 - 3.15.1 Access to valves
20 - 3.15.2 Attachment to vehicle
21 - 3.15.3 Alternate anchoring
22 - 3.15.4 Multiple cylinders
22 - 3.16 CYLINDER LOCATION AND GROUND CLEARANCES
23 - 3.17 PROTECTION
24 - 3.18 HEAT SHIELDING
26 - SECTION 4 FUEL SERVICE LINE
26 - 4.1 APPLICATION
26 - 4.2 RIGID PIPING
26 - 4.3 FLEXIBLE PIPING
26 - 4.4 JOINTS AND CONNECTIONS
26 - 4.5 PIPING INSTALLATION AND PROTECTION
27 - 4.6 PIPING OR FITTINGS IN ENCLOSED SPACES
27 - 4.7 TRAILERS AND SEMITRAILERS
28 - 4.8 FUEL HOSE FOR PRESSURE NOT EXCEEDING 100 kPa
28 - 4.9 BREAKAWAY COUPLING
29 - SECTION 5 FUEL CONTROL EQUIPMENT
29 - 5.1 APPLICATION
29 - 5.2 FUEL METERING SYSTEM
29 - 5.3 FUEL SELECTOR
29 - 5.3.1 General
29 - 5.3.2 Optional fuel type
30 - 5.4 PETROL OR DIESEL SYSTEM MODIFICATIONS
30 - 5.5 ELECTRICAL WIRING
30 - 5.6 ENGINE MANAGEMENT SYSTEM
31 - SECTION 6 INSPECTION, TESTING AND COMMISSIONING
31 - 6.1 APPLICATION
31 - 6.2 USED EQUIPMENT
31 - 6.3 MODIFICATIONS AND REPAIRS
31 - 6.4 PRECAUTIONS
32 - 6.5 INSPECTION
32 - 6.6 LEAK DETECTION
32 - 6.7 CYLINDER
32 - 6.8 INSTALLATION TEST
32 - 6.8.1 General
32 - 6.8.2 Gastightness of compartment and sub-compartment
32 - 6.8.3 Leak testing of gas system
32 - 6.8.4 Test of fuel changeover system
32 - 6.8.5 Test of automatic full shut-off device (AFSOD) operation
32 - 6.8.6 Water system tests
33 - 6.8.7 Visual inspection
33 - 6.9 PERIODIC INSPECTION
33 - 6.9.1 General
33 - 6.9.2 System check
34 - 6.10 NON-RETURN VALVE TEST
35 - SECTION 7 CERTIFICATION, COMPLIANCE PLATE, MARKINGS AND LABELS
35 - 7.1 APPLICATION
35 - 7.2 CERTIFICATION
35 - 7.3 COMPLIANCE PLATE
35 - 7.4 LABELS AND MARKINGS
35 - 7.4.1 Vehicle identification
36 - 7.4.2 Refuelling information plate
36 - 7.4.3 Selector
36 - 7.5 OPERATING INSTRUCTIONS
37 - APPENDIX A - LIST OF REFERENCED DOCUMENTS
40 - APPENDIX B - REGULATING AGENCY INFORMATION
43 - APPENDIX C - NEW ZEALAND REFUELLING CONNECTION AND DUST PLUG
44 - APPENDIX D - LEAK DETECTION METHODS
44 - D1 SCOPE
44 - D2 COMBUSTIBLE GAS DETECTORS
44 - D3 TRACE GAS DETECTORS
44 - D4 FOAMING AGENTS
45 - D5 TOTAL IMMERSION
46 - APPENDIX E - PROCEDURES FOR DEMONSTRATING COMPLIANCE WITH EXHAUST EMISSION STANDARDS
46 - E1 SCOPE AND VEHICLE SELECTION
46 - E1.1 Scope
46 - E1.2 Test fuel composition
46 - E1.3 Use of certified kits on engine/vehicle variants
48 - E2 ADR79/00 VEHICLES
48 - E2.1 General requirements
48 - E2.2 Testing requirements
49 - E2.3 Documentation and installation requirements
49 - E3 ADR79/01 VEHICLES
49 - E3.1 General requirements
49 - E3.2 Testing requirements
50 - E3.3 Documentation and installation requirements
50 - E4 ADR70/00 VEHICLES
50 - E4.1 General requirements
51 - E4.2 Testing requirements
52 - E4.3 Documentation and installation requirements
53 - E5 ADR80/00 AND ADR80/01 VEHICLES
53 - E5.1 General requirements
53 - E5.2 Testing requirements
53 - E5.3 Documentation and installation requirements

Sets out requirements for natural gas (CNG) fuel systems for motor vehicle engines used for propulsion or auxiliary functions. It also specifies requirements for the design and construction of component parts as well as their installation, testing, commissioning and periodic inspection.

This Standard specifies requirements for natural gas (CNG) fuel systems for engines mounted on motor vehicles, either for the propulsion of the vehicles or for driving some auxiliary function, e.g. a mixer or a pump. It provides requirements for the design and construction of component parts, and for their installation in vehicles, and for tests, commissioning, and periodic inspection. It applies to all vehicle types, e.g. rigid chassis, articulated chassis and semitrailers. This Standard does not apply to forklifts, floor sweepers, polishers, tow tractors, elevating work platforms and industrial stationary engines and to other CNG usage, such as the gas supply system for appliances in caravans, mobile homes or for the propulsion of marine craft. This Standard does not cover the areas where major structural modifications are to be carried out to the vehicle (major structural modifications are those not defined in Clause 1.7). Prior to commencement of such work guidance should be sought from the vehicle manufacturer or a professional engineer who is experienced in the automotive disciplines.

First published in Australia as AS 2739-1984.
Second edition 1992.
First published in New Zealand in part as NZS 5422.2-1980.
Second edition 1987.
NZS 5422.3 first published 1991.
AS 2739-1992, NZS 5422.2:1987 and part of NZS 5422.3:1994 jointly revised, amalgamated and redesignated as AS/NZS 2739:1999.
Fourth edition 2003.