For people with a hearing loss, devices with flashing lights and vibrating "alerts" can help make day-to-day life safer. One of the    most common types of lighting      alerts is a strobe light. Strobe lights are very visible, providing an effective way to signal that someone is at the door, that the telephone is ringing, that someone is calling out for help, that a child is crying, or that a smoke detector is going off. A strobe light and alarm that relay a signal to a vibrating disc, bed-shaker, or pager increases the likelihood of a safe response.