1 Breakages are less as the boards are much tougher and have fibers reinforcing in them. 2  they damage less easy from general wear and tear in everyday use in a home or office. 3  It offers slightly better acoustics than standard board.  It is a superior product in case of fire.
It is normal for the solenoid to make noise, it clicks when the valve is turned on or off. It also is normal for a very soft buzzing sound to be heard when the valve is activated, but you should not be able to hear it unless you put your ear near it. If you can easily hear it buzzing, that is not normal.
Sharks hear sounds with frequencies ranging from 10Hz to 1KHz, and are especially responsive to sounds 500Hz or lower. In tests, the inventor found that sharks will not come within five feet of the noisy device, which if worn by swimmers, could protect them in the water (illustrated)