Foreword

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This document was prepared by Technical Committee ISO/TC 22, Road vehicles, Subcommittee SC 41, Specific aspects for gaseous fuels, in collaboration with Technical Committee ISO/TC 188, Small craft.

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Introduction

This document specifies requirements for the installation of equipment for the use of compressed natural gas (CNG) and liquified natural gas (LNG) in the propulsion systems for small crafts.

This document includes procedures which the use substances and procedures that can be injurious to health if adequate precautions are not taken. This document refers only to technical suitability.

Natural gas, either in gaseous (CNG) or liquid phase (LNG), is a very efficient and ready-to-use solution which can facilitate compliance with the more stringent environmental regulations as well as the compliance with the principles of the circular economy. In this context, regulations can concern the impact of a product on the environment during its entire life cycle, including the expenditure of energy and during all phases such as use, scrapping and recycling of materials. Some parts of this document address also environmental aspects.

1 Scope

This document specifies the requirements for the installation of compressed natural gas (CNG) and liquefied natural gas (LNG) propulsion systems and components on small crafts.

This document does not cover appliances with directly attached gas cylinders, such as portable container.

2 Normative references

3 Terms and definitions

4 Components

4.1 General provisions

4.2 CNG cylinders and LNG containers

4.3 Fuel system components

5 Installation requirements

5.1 General requirements

5.2 Installer of the CNG or LNG system

5.3 Additional CNG or LNG systems not connected to the propulsion system

5.4 Modifications to the structure of the craft

5.5 Container or cylinder installation

5.6 Components fitted to the fixed container/cylinder

5.7 Gas pipes and hoses

5.8 Other components

5.9 Electrical installation

5.10 Fuel selection system

5.11 Gas detection

5.12 Forced ventilation

6 Fire-extinguishing equipment

7 Owner's manual

7.1

7.2

7.3

7.4

8 Commissioning

8.1 General

8.2 Tightness test

8.3 Leakage test

8.4 Initial filling of the container/cylinder and the system with LNG/CNG

8.5 Fuel system test

8.6 Water trial

Bibliography