To get the full benefits of a bath bomb, you should sit in a bath bomb for at least 15 to 30 minutes. However, there is no maximum time, so you can enjoy the bath for as long as you like.
Bath bombs are typically safe to use as often as you'd like. However, if you have sensitive skin, you should limit the use to a few times a week.
For some, sitting in baths can be boring, but for others, sitting in a tub until their skin begins to wrinkle is rejuvenating. Generally, none of these products will harm you if you decide to take an extended soak in them. You should be fine to soak in them until you are finished enjoying your bath. However, an exception to this is if you have sensitive skin.
Bath bombs are just as much about the mental experience as the physical one. They can help set the mood for a relaxing soak. To experience the full benefits of bath bombs, you should set up the surroundings to compliment the mood even more.