Dan
Contributor
No expert here of course, but if the pressure build up is delayed, would that not mean the pain is also delayed? This may cause a diver to continue to descend--when things "catch up" could that mean even a worse situation than if the pain started when it normally would without the plugs? I suppose if the diver using the plugs descends VERY slowly (even if no pain at all) all pain could be eliminated?
I'm fuzzy on the physics. My reasoning may be completely backwards.
Delayed pressure built up is similar to descending slowly. That simply means you have time to equalize. So the slow equalization rate matches with the delay of pressure built up.
The pain is usually associated with the outside pressure rising faster by the rate of descent than the inner ear can equalize due to narrow passage from the nose to inner ear. So the ear drums will be under stress (pain) as the outside pressure is greater than the inside pressure. Having a tiny hole plug will delay the pressure built up on the outside of the eardrum and giving time for the inside drum pressure to catch up with the outside pressure, similar to descending very slowly.
If diver still feels the pain, then he / she just needs to ascend to stop the pressure built up. There won't be a delayed pain if there is no differential pressure across the ear drum.