(1)
No person shall, without the written permission of the Commissioner, use or employ in any factory or any other place, any steam-whistle or steam-trumpet for the purpose of summoning or dismissing workmen or persons employed.
(2)
The Commissioner may at any time revoke any permission which he has given for the use of any such instrument as aforesaid, on giving one month's notice to the person using the same.
(3)
Provided that nothing in sub-section (2) shall be deemed to require one month's notice to be given by the Commissioner, if he suspends or revokes any such permission for any reason specified in sub-section (3) of section 479.