2 October 2014 Chapter 25 - Definitions - radioactivity; and - environmental persistence. • Any substance emitting or breaking down to a substance with any of the above properties upon entering the environment; and • Any substance which has any of these hazardous properties at any stage in its life-cycle. HAZARDOUS WASTE means hazardous substances which are unwanted and economically unusable. HIGH SPEED SHIP means a ship which has a registered length exceeding 30 metres and is capable of a maximum speed, in metres per second (m/ s), equal to or exceeding: 3.7 0.1667 where σ = displacement σ corresponding to the design waterline (M³). HEIGHT in relation to a building means the vertical distance between ground level at any point and the highest part of the building immediately above that point (See Fig. 25.1). For the purpose of calculating height account shall be taken of parapets but not of : a) Radio or television aerials; b) Aerials, antennas, mounts, lightning rods and other incidental associated features with radio communication facilities; Next page is 25 -7 25 – 6A