"CE" RULES FOR FUEL, WATER AND HOLDING TANKS

On outboard engines fuel tanks, for instance, plastic has replaced iron introducing a number of advantages such as weight saving and low maintenance costs. Thanks to new technologies, it is nowadays possible to produce plastic materials suitable for building fuel thanks, according to the CE rules. Those materials are usually employed on outboard engines tanks, which are classified by the CE rule as "thanks and fuel plants isolated from the hull structure". The rules are very restrictive, forcing the manufacturing companies to follow inflexible guide-lines to design, manufacture and test the tanks: shapes, loads and critical application must be considered, in order to comply with the rule and to offer a safe product. The filler system, for instance, must allow an expansion volume equal to 5% of the total tank volume even in overflow situations, while the fuel reserve must be equal, at least, to 5- 8% of the total volume.

Two tanks structure manufacturing techniques are available: one is the "blowing" and the other is the "rotational" procedure. Accurate post-manufacturing tests are required for both. Strength tests (shear and impact), corrosion tests, permeability tests and fire resistance tests are included.

The feeding pipe, and its hand pump, must withstand the fuel corrosion and must be able to preserve its mechanical properties from -30° to +60°. It must withstand the sea water and the sun light erosion as well.

According to the CE rule, all removable tanks up to 30 liters of total capacity must be red or orange, and must be fitted with a handle and a filling cup with breather. Tanks with larger capacity must comply with the rules for fixed plants. They are already available on the marked, both built from metal or plastic materials.

The new capacity limit introduce different building techniques as well. The plastic tanks manufactured with the blowing technique must comply with the ISO 10088 rule. They are usually parallelepiped shaped and with total capacity in the 30 to 100 liters range. It is possible, however, to manufacture those tanks with the rotational technique, although the resulting shape may be complex and may not comply with the stiffness limit introduced by the ISO 10088.

Metal tanks (built from aluminum or steel) are, on the other hand, more versatile. They can be manufactured in a wide variety of shapes and capacities, according to the CE rule anyway. Particular shapes or installation must be approved by a Certification Society (such as Rina, ABS, etc.) with prior examination of building drawings.

All tanks (removable or fixed) must be tested. Without going too deep on the rules for building and installing the tanks (inlet sizes, breather position and inspection openings) we believe it is useful to know that each tank on board must have a plate stating the following information: manufacturer name and address, type of fuel stored (gasoline or diesel), allowable pressure, capacity (in liters), type and number of CE certification.

All existing fixed plants must be up dated before June 1998.

Polytilene fresh water tanks are available on the market in several dimensions and capacities. They are usually equipped with a suction pump or a suction pipe with manual or electric pump.

Waste waters tanks will be mandatory on board. A discharge line must be fitted, in accordance with the rules for disposal of organic waste. Waste waters tanks of 30, 40 and 50 liters capacity are currently available on the market. Those tanks should be installed next to the w.c. macerator so to avoid air bobbles in the plant. The breather should be fitted with an active filter, to prevent unpleasant smells.

For further information, or details on new regulation and installing instructions, please contact one of the tanks manufacturing company or Can Marine Plastic, Raffa di Puegnago (BS) - Italy, tel.: +39-365-651001 email maubelli@tin.it, whose support has been essential for publishing this brief presentation on the new CE rules for pleasure boats tanks.