51. An employer shall ensure that—

(a) lifting equipment is operated by a competent person or by a person who is under the direct supervision of a competent person for the purpose of training,

(b) no person under 18 years of age is employed to—

(i) give signals to the operator of lifting equipment driven by mechanical power or

(ii) to operate any such equipment,

(c) every signal given for directing the movement of lifting equipment—

(i) is distinctive in character, and

(ii) such that the person to whom it is given is able to hear or see it easily, and

(d) signalling devices are—

(i) properly maintained, and

(ii) the means of communication are adequately protected from accidental interference.