Mask Clearing Reflex

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EliotD

Contributor
Scuba Instructor
Messages
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Location
Northern Virginia
# of dives
I'm a Fish!
Hiya,
I am currious if anyone has any thoughts on what happened to me last night. I was on a night dive (my 31st dive and 7th night dive) with a group. I noticed that my mask was leaking a bit because of the way my hood sits. So, having done this before, I signaled my buddy, pulled my mask off and tried to replace it. Up to this point its all routine, I have no problem with mask removal/replace/clear. Well this time I found that I couldnt breath at all through the reg. Since we were in like 12 ft, I just swam up, so all is well. I checked my gear, everything okay, so it wasnt an equipment issue.
The divemaster for this night dive told me this was the mammalian dive reflex and that its normal, my question is, why hasnt it happend to me before? Any ideas?
 
Yea I read the Wikipedia article, I agree its not what happened. I just wish I knew what it was. Just for fun I filled my bathtub with COLD water and stuck my head in with the reg in and mask on. I pulled the mask several times and it didnt happen...I did however, get very cold.
 
this usually happens in cold water, and it has happend to me once wayy back when.

Im guessing you put your mask on before you got in the water, so your face didnt have a chance to get used to the water temp. Then when you were underwater with the leak you knew what to do and took off your mask quickly, performing the skill as if you've done it a million times. Now the reason you stopped breathing, or felt like you couldnt breath. This was the shock of the cold water hitting your face and it is part of the mammilian diving reflex. Wikipedia doesnt exactly go into detail there of what the MDR entails.

They did a test on new born babies with this. They would splash a little cold water on there faces and instantly without knowing whats going on, they started holding there breath. Its simply instinct.

Just rember that if this happens to you again, and your deeper that coming up might not be an option. You just have to calm down, wait a second, dont panic, and eventually after like 5 seconds you will be able to breath again.
 
When you get water up your nose you body thinks you're drowning, and won't let you breathe the water since you don't have gills. This happened to me on my OW certification dive and I had to surface and start over. On my second try I had better airway control and finished easily.
 
I have the same problem sometimes. I freeze up if my mask totally floods, like I can't risk breathing beacuse I might inhale water. I have the same problem swimming in the pool without goggles.

When it happens while diving, to get a grip I do the following:
- remember that your normal breathing rhythm underwater never involves inhaling through your nose. If you resume doing what you were doing before you'll be fine. This can help you calm down.
- as long as you have air in your lungs, you can safely exhale without any risk of inhaling water. So try exhaling (somewhat forcefully) through your mouth to reopen your airway, then the natural reaction should be to inhale through your mouth.

I still feel like I need to improve my ability to handle this. I've considered trying a technique I've heard of: flood and clear the mask on the surface before descending on every dive to get acclimated to the water temp. I'm not sure if it will help. My current approach is just to practice mask skills regularly.

Ben
 
I always stick my face in the water with my reg, no mask prior to every dive for that purpose. Haven't had that issue since. Especially since its chillier water I have been diving.
 
Happens to me every time I take off my mask in cold water. Warm water isn't such a problem, but cold water? If I flood my mask or remove it, I can't breathe. It's something I need to practice to get comfortable with, since I pretty much only dive in the cold cold waters of the PNW. Anyway, it's normal. Just practice. Like anything, the more you do it, the easier it gets.
 
Practice is definitely the key to dealing with this. I was definitely not a fan of breathing off my reg without my mask on. A couple of days worth of instructors ripping your mask off while pool diving will definitely teach you how to get over that. One thing that may help is snorkeling in a pool without a mask. Wll get you used to breathing with your face totally wet. Took me a while.
 
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