Helpful Hint


In some cases, such as this combination horn/strobe light installed in a gymnasium, mechanical protection is provided to prevent damage to the fire alarm notification appliance. Guards or covers installed over an audible or visible notification appliance must be UL listed for such use. The audible or visible output of the notification appliance must be "de-rated" based on how much light or sound is blocked by the protective cover. The information regarding the loss of output is available from the manufacturer.

NOTE: This is an unformatted excerpt from our online fire protection training library.