It has always been said that diving in mud (bentonite) is very hazardous due to the risk of wall collapse. I have done many times and I agree that it was not my cup of tea to dive and work in it. You need a lot of extra weight to be able to go down.
Breathing (exhalation) is difficult, movements are restrained and yes, sometimes you have the sensation that some parts of the wall are falling on you. However, within the last fifty years, I have never heard about one single accident.
Of course, during the first 35 previous years internet was not yet available thus, the collection of accurate data was difficult to obtain. Thanks to internet! Nowadays, nearly all the commercial divers of the world are in close contact and the communication of reliable information goes much better.
Here’s my message to all parts of the world ; Have you ever heard of this specific type of accident?
Shared via https://www.facebook.com/CommercialDiving/timeline from Francis Hermans