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.
1 Stridor is a symptom not a diagnosis and it is important to find the underlying cause. 2  Stridor is a loud, harsh, high pitched respiratory sound. 3  It may start as low-pitched 'croaking' and progress to high-pitched 'crowing' on more vigorous respiration.