It is common knowledge in psychic circles that the astral body doesn't leave or at least stays close to the physical body of the deceased. The reason is because most people don't prepare for their deaths, consequently they don't know what to do after their deaths. Not knowing any better, they “stick around”.

In one of his book, Robert Monroe mentioned such a case of a man whose physical body was lying on the ground because the man died in a battle, yet his astral body tried to animate the physical body over and over, not realizing and understanding what has happened.

In many cases people decided they wanted their bodies to be cremated. The importance of how crematoriums are built is important only if the theory of “catching souls” after death is true.

What other easier way exist to catch “souls” then at a crematorium?
The time when the soul is at the body that is getting cremated.

Are there Faraday cages or some kind of electrical/magnetic force fields around those chambers where the physical body is cremated, to catch the departing “souls”?
If there is, it certainly won't be advertised; “it is a force field to capture “souls” but disguised as some kind of safety or protection device.

Either way, it is a prudent act not to stick around the expired body.

“The quest to conquer death is as old as man himself. We conjure dark angels, whose untimely arrival we hope to avert with guile and perseverance. But in the end it is inevitably the grave, not hope, which prevails.”