There are several different types of swimming pool alarms on the market today for both above ground inground swimming pools: Surface alarms, subsurface, personal immersion alarms and pool perimeter devices. Each type of alarm is designed to sound an alert if a small child or pet should fall into the pool or wander too close.Swimming pool alarms play a huge role in pool safety—even if you don’t have children or pets of your own. Neighborhood children or pets can wander into your backyard at any given time, so you should always outfit your pool with an alarm. An alarm is not a direct replacement for adult supervision, but is in an added safety feature that allows you to comfortably step away from the backyard pool. Out of all the options, the most popular and affordable pool alarms attach to your back door. The Poolguard pool door alarm DAPT-2 is a key piece of equipment to incorporate into your backyard.