For the purposes of sections 131(3) (powers of road works authority in relation to reinstatement) and 149(2) (provisions as to reinstatement of sewers, drains or tunnels), the prescribed period is 7 days for all descriptions of remedial works unless the defect is considered by the road works authority or responsible authority, as the case may be, to be hazardous to the travelling public in which case the prescribed period is 24 hours.