The useful life of flexible hose depends on many factors, including storage and
operating conditions, and the hose may need to be changed several times
during the lifetime of your boat. Flexible hose also has a lower fire resistance
than metallic pipe and for all these reasons it is recommended that the length
of hose used in the fuel system is restricted to the absolute minimum, i.e. the
minimum length necessary to cope with vibration or the movement of engines
and boat structures.

The additional benefit of this is that the amount of hose exposed to the risk of
early failure through damage from heat and abrasion will be minimised. All hose
used in the fuel system must be fire resistant to at least 21/2 minutes, as
specified in the internationally agreed marine fuel hose Standard (BS EN ISO
7840), although there are hoses available with superior fire resisting qualities
(e.g. BS ISO 15540). Both of these hoses will also meet the current
requirement for reinforcement and wall thickness.

Spill racks (i.e. the pipes which are attached to, and carry return fuel from, the
injectors on diesel engines) must be made from metallic pipe or fire resistant
hose. Some automotive engines currently on the market, which have been
adapted for marine use, are fitted with push-on, non-fire resistant hose. This
arrangement is unacceptable. Conversion kits are available for most engines
and these are acceptable provided they are competently fitted. You should
contact your marine engine supplier for further details.

Engines that are certified to International Standards, i.e. ISO 16147 for
diesel, ISO 15584 for petrol, are acceptable since these Standards support the
Recreational Craft Directive. It's recommended that you bear these Standards in
mind when buying an engine. [2.14]