Is it safer to sleep with your bedroom door closed?

According to Feng Shui, a closed door keeps positive energy inside.

One of the Feng Shui principles about bedrooms is to avoid sleeping with an open door. This is because all of the positive energy in the room can escape. It opens up your room to negative chi. Closing it will prevent this and give you a sense of security and safety. You will also have a calmer and more peaceful mind.