Clause 2 Bell or Gong

(1) Intensity of signal

A bell or gong, or other device having similar sound characteristics, must produce a sound pressure level of not less than 110dB at a distance of one metre from it.

(2) Construction—

(a) bells and gongs must be made of corrosion-resistant material and designed to give a clear tone; and

(b) the diameter of the mouth of the bell must not be less than 300 millimetres for vessels of 20 metres or more in length.

(c) where practicable, a power-driven bell striker is recommended to ensure constant force, but manual operation must be possible; and

(d) the mass of the striker must not be less than 3% of the mass of the bell.