(1)Where a motor vehicle or trailer is weighed under section 78 of this Act, a certificate of weight must be given to the person in charge of the vehicle, and the certificate so given shall exempt the motor vehicle and the trailer, if any, from being weighed so long as it is during the continuance of the same journey carrying the same load.
(2)On production of his authority—
(a)a certifying officer appointed under the [1981 c. 14.] Public Passenger Vehicles Act 1981, or
(b)an examiner appointed under section 68 (1) of this Act, or
(c)any of the Secretary of State’s officers authorised by him in that behalf,
may at any time exercise with respect to the weighing of vehicles of a class prescribed for the purposes of section 63 of this Act and goods vehicles generally all such powers with respect to the weighing of motor vehicles and trailers as are exercisable under section 78 of this Act by a constable authorised as mentioned in subsection (8) of that section.
(3)The provisions of section 78 of this Act shall apply accordingly in relation to vehicles of a class so prescribed and goods vehicles generally—
(a)as if references to a constable so authorised included references to such a certifying officer, examiner or officer of the Secretary of State, and
(b)as if the reference in subsection (6) to the authority on whose behalf the requirement is made were a reference to the Secretary of State, and
(c)as if the reference in that subsection to the Secretary of State were a reference, in relation to England and Wales, to the Lord Chief Justice of England and, in relation to Scotland, to the Lord President of the Court of Session.
(4)A certificate in the prescribed form which—
(a)purports to be signed by an authorised person (within the meaning of section 78 of this Act) or by a person exercising powers by virtue of subsection (2) above, and
(b)states, in relation to a vehicle identified in the certificate, any weight determined in relation to that vehicle on the occasion of its being brought to a weighbridge or other machine in pursuance of a requirement under section 78(1) of this Act,
shall be evidence (in Scotland, sufficient evidence) of the matter so stated.
(5)If, for the purposes of or in connection with the determination of any weight in relation to a vehicle which is brought to a weighbridge or other machine as mentioned in section 78(1) of this Act, an authorised person (within the meaning of that section) or a person exercising powers by virtue of subsection (2) above—
(a)drives a vehicle or does any other thing in relation to a vehicle or its load or a trailer or its load, or
(b)requires the driver of a vehicle to drive it in a particular manner or to a particular place or to do any other thing in relation to a vehicle or its load or a trailer or its load,
neither he nor any person complying with such a requirement shall be liable for any damage to or loss in respect of the vehicle or its load or the trailer or its load unless it is shown that he acted without reasonable care.