4.—(1) The Department may by order designate as a sports ground requiring a safety certificate any sports ground which in its opinion has accommodation for more than 5,000 spectators.
(2) The Department may by order substitute, for the number for the time being specified in paragraph (1), such other number as it considers appropriate.
(3) An order under paragraph (2)—
(a)may make different substitutions for different classes of sports ground; but
(b)does not affect the validity of any designation previously made.
(4) The Department—
(a)may estimate, by any means which it considers appropriate, for how many spectators a sports ground has accommodation; and
(b)may require any person concerned with the management of a sports ground to provide the Department within such reasonable time as it may specify with such information as it considers necessary for the purpose of making such an estimate.
(5) A safety certificate may be either—
(a)a certificate issued by the council for the district in which a sports ground is situated in respect of the use of the sports ground for an activity or a number of activities specified in the certificate during an indefinite period commencing with a date so specified, or
(b)a certificate issued by that council in respect of the use of the sports ground for an activity or a number of activities specified in the certificate on an occasion or series of occasions so specified.