(1)During the weekly close time the inscales and heck of each box in a salmon weir shall be either removed or opened out in such a manner that a clear opening of not less than[F1 1.2 metres] in width is left open therein from the top to the bottom of the box and a free, direct and uninterrupted space of that width is effectually secured for the passage of all fish, both up and down, through the box.
(2)If in respect of any salmon weir the provisions of subsection (1) are not complied with, the occupier thereof shall be guilty of an offence and shall be liable on summary conviction to a fine not exceeding [F2 £500] in respect of each box in the weir the inscales and heck whereof are not removed or opened out as required by subsection (1).
(3)Nothing in subsection (2) shall be construed as rendering liable to any penalty a person who satisfies the court that he was prevented by floods, storm or stress of weather from complying with subsection (1) during the continuance of that prevention.