Abstract
Small closed sea shipping regions (such as the Baltic Sea) are specially vulnerable to consequences of ecological disasters due to spills of fuel oil used for ship propulsion and carried in single-plating double-bottom tanks. An alternative solution (against the recommended double- plating structure) was proposed. It consists in applying the second, elastic protection barrier to decrease risk of oil spills resulting from loss of tightness of ship plating in consequence of e.g. collision or grounding.