If your parent uses or plans to use a personal emergency response system (PERS), ask the service provider about a waterproof transmitter. These are often a standard feature, but it's a good idea to check. The transmitter is the portable battery-operated device -- usually available as a pendant, wrist band, or belt clip -- that houses the push-button alarm. Waterproof transmitters are ideal when your parent is bathing, a time when slips and falls can easily occur.