Check your tank and fittings, pipework and bund for leaks and signs of corrosion, oil staining, rust, discolouration, cracks and crazing.
Archwiliwch eich tanc a'r gosodiadau, y pibellau a'r bwnd am ollyngiadau ac arwyddion o rydu, staeniau olew, afliwio a chraciau mawr a mân.