surface - supplied air

[Roger McKinney]

Do free flow hard hats, using forced air. Surface - Supplied air use the same dive tables as a scuba diver.

 

[Steve_C]

Assuming that the air is free to flow out all the time then to maintain the air pocket the air has to offset ambient water pressure. So I would think that the pressure issues are the same so the answer is yes. But might be different depending on the gear. This answer based on theory as I understand it and not actual experience.

 

[Subcooled]

The Siebe-Gorman 12-bolt hard hats had an exhaust valve that had to be manually triggered by tilting the head, and I guess (I do not know) that the pressure inside the helmet mostly corresponded to the ambient pressure. Hence, no major difference. I do not know how the modern diving helmets made out of lesser materials work.

 

[Subcooled]

The only thing to consider is the pressure of inhaled air i.e. the pressure inside the helmet. A professional diver may give a better answer.

 

[rjack321]

the air in your lungs must be at ambient pressure or you either will have crushed lungs (unable to breathe) or an embolism.

so yes, same tables and/or computers.

 

[Subcooled]

My previous answers are wrong.

I have a strong feeling that you should read about dysbaric osteonecrosis.
How many hours a day are you going to work?
Please consider professional diving work safety regulations.

I cannot help any further, as my knowledge is limited.