Possible Barotrauma diving a dry hood?

[Zesty]

Am a Great Lakes diver who dives dry the majority of the time. Decided to go with a dry hood and beanie this year vs a neoprene hood. First three dives to 30 ft to get used to the hood were uneventful. On a trip this past weekend, was at ~40 ft and had the discomfort of a squeeze. Up 5 feet, equalize, then continue to descend. Continued to have minor squeeze all the way to 120 ft, but always came up, cleared and descended. After surfacing and doffing my suit, a co-diver noticed blood from my ear. I aborted the rest of the weekend, discussed with DAN, and got the ear checked out at ER (no obvious signs of torn ear drum). Have follow up with ENT Dr today.

My question: Has anyone had a bad experience with a dry hood, and could the hood or something related to the hood have caused this? Just looking to root cause this to avoid issues in the future. Have never had issues with a regular neoprene hood on 180 previous dives

 

[Peter Slater]

I like my dry good but I have to be very careful with it. I am not a doctor but started using it after getting a severe ear infection and learned a lot about how equalization works.

You have to equalize because the pressure in your eardrum not equal to the pressure outside of it. In a wet hood the outside pressure increases gradually as you go down, and causes your eardrum to bow in. The discomfort you feel is caused by this bowing. Equalization puts a bit of air inside your ear which increases the internal pressure and returns the drum to normal.

They say not to dive with your ears plugged because it will trap air on the outside of your ear that will not be equal in pressure to the ambient water. If you keep going down and "equalizing" the inequality can grow to be dangerous if released in a snap. Imagine the discomfort of diving to 100ft without equalizing.

With dry hoods you have to be careful to equalize the inside air pocket to the depth just like you would a drysuit. This prevents it from plugging your ear. What could have happened is that you started the dive not equalizing the hood but then the seal broke and the pressure snapped. This could have over extended your ear drums which caused bleeding.

My dryhood is setup with a neck seal and is not attached to my drysuit. I wear it with a thin beanie. I decend very slowly and tug at the neck seal to let in a trickle of water to equalize. I don't stay perfectly dry but I found it easier to equalize this way then when it was attached to my suit. Having the hood separate also makes getting into my drysuit more comfortable.

 

[Zesty]

I like my dry good but I have to be very careful with it. I am not a doctor but started using it after getting a severe ear infection and learned a lot about how equalization works.......

Thanks Peter - great information. I am working along the same principle you describe - the face seal was too "good" around my mask, causing the condition you describe. My suit is a DUI with Zip-Seals, and the dry hood / neck seal is integrated into the neck zip-seal. I do wear a beanie. I need to begin working out solutions to deal with this, or go back to diving wet. My need is due to having no hair on my head now, and getting cold at depth.

 

[Zef]

Thanks Peter - great information. I am working along the same principle you describe - the face seal was too "good" around my mask, causing the condition you describe. My suit is a DUI with Zip-Seals, and the dry hood / neck seal is integrated into the neck zip-seal. I do wear a beanie. I need to begin working out solutions to deal with this, or go back to diving wet. My need is due to having no hair on my head now, and getting cold at depth.

If you are looking for something warm for cold water drysuit diving and decide to go back to a neoprene style hood, i recommend you look into the Waterproof H1 5/10mm Polar Evoluted Hood or the H1 5/10 Sandwich hood.

Waterproof H1 5/10
Waterproof H1 5/10 hi-vis
Waterproof H1 5/10 sandwich

I dive year round in waters that get down to 2c (35.6f). One of the above hoods should work well for you.
I have also used a 6mm neoprene Beuchat hood and it has kept me toasty as well.

I find that sometimes the seal of neoprene hood can be so good that an air pocket forms between the hood and my ears and that can result in an ear squeeze. I often pull one side of the hood away from my face to flood my hood at the beginning of a dive before descending to ensure a squeeze doesn't happen, once was enough for me. My head heats up the water layer inside the hood fairly quickly so any discomfort is of very short duration.

-Z