Choosing the right pool safety devices largely depends on if your pool has a safety fence or direct access from your house. If your pool does, then a gate alarm or door alarm is for you. If your pool is located in a place where you can get to it in more than one way or there is no fence, then you should select an alarm that prevents anyone from entering your pool without your knowledge. However, if your pool can be equipped with either type, then it comes down to personal preference.