The idea behind smoke alarms is fairly simple. If you are alerted by the smoke before he flame reaches your location, you will have more time to escape.
Multiple smoke alarms that can signal each other can alert you even before the smoke reaches your location. These new alarms are ‘interconnected.’ This can be done either with an actual wire or with a dedicated RF (radio frequency) signal.
Many of the homes with fatal home fires were found to have smoke alarms with dead batteries. Either the batteries were simply to weak to operate the alarm or had been removed in anticipation of replacement and simply forgotten.
To resolve this problem newer smoke alarms are supplied with ten year batteries and can be hardwired to the homes electrical system.
Hardwiring and interconnection is a code requirement of new construction in most areas. This presents far more time to get your family safely away from the house in the event that becomes necessary.
A licensing requirement for Baltimore County rental properties requires hardwired and interconnected smoke alarms regardless of the age of the property. Since many of these properties will be retrofitted for smoke alarms the wiring requirement becomes much simpler by the use of ‘radio linked’ alarms.
Combination alarms that detect carbon monoxide (CO) gases as well as smoke are available to accommodate homes that require them. Interconnection provides the same advantage of time as do the smoke alarms.