Breathing Difficulties

Question
I am a recreational diver and go diving 3-4 times every year or two.  I do not have my own equipment and have had some anxiety using rental regulators.  Some were beat up and were only good as a second regulator, but were installed as the primary regulator.  As background, I got an asthma attack after cleaning my mother抯 furniture out of her house in the late 1990's.  The doctors said that it had to be related to dust or mold that was disturbed as we move the furniture that had been in place for decades.  Since then I have had no additional attacks.  Test show that I have very little susceptibility to asthma.  I run, bike, hike, and swim regularly to keep in shape.  However, particularly at the surface if I have trouble breathing through a regulator, I have to work hard to calm my anxiety and go under since it feels just like an asthma attack.   I have absolutely no trouble snorkeling.  I have had regulators that are hard to breathe at any depth.  Several years ago, I used a regulator provided by a dive school.  In the pool doing my refresher class, this regulator had a knob on the side of it that made breathing effortless - just like a snorkel.  Unfortunately, I have no idea what kind of regulator it was.  Do you have any suggestions for the kinds of regulator to buy that would ease the difficulty in breathing from the surface on down?  I am headed to Maui for a Christmas vacation and would love to do some diving.  I want to really enjoy the experience and put this breathing anxiety behind me.

Answer
Hi Alan,

Thanks for a very informative question.  Your extensive history gives me more insight into your problem.  I'm not in a position to give you medical advice but it appears that you've dealt with your asthma problem in a practical manner.  However, it seems that the anxiety continues to give you some hesitation and a balky regulator appears to increase your anxiety.  

Knowledge is power so let me give you a little insight into the workings of a scuba regulator.  As you've discovered, rental regulators are not always in the best of condition.  A regulator is tuned by the service technician and this tuning is a major factor in how easily the regulator breathes.  If tuned properly, the regulator is right on the edge of free flow.  That, as you probably know, is the tendency of the regulator to release air even when it isn't in your mouth.  To prevent free flow, the technician may move the tuning farther away from this point of free flow but that makes the regulator harder to breathe from.  So...tuning (or the lack of it) may be responsible for the difficulty you experienced in breathing from the regulator.

Some regulators, as you've pointed out, have an adjustment knob on the side of the regulator and it's purpose is to adjust the breathing resistance of the regulator so you can move it closer to free flow if needed.  The range of travel of the knob must be properly adjusted as well or it won't work properly.  That's the job of the technician.  So you can see that the technician is the one primarily responsible for the ease of breathing of your regulator.

This adjustment knob is found on at least one model for each major manufacturer.  It's considered a performance enhancement and usually costs a bit more.  Any of the name brands will work just fine.  

Purchasing your own regulator will allow you to get a well tuned model and to protect it from abuse by other users.  My suggestion would be to check with your local dive shop(s) and see what brands they carry.  Select your regulator from one of these brands, specifying that you want an adjustable second stage (that's the knob).  The advantage to buying from a dive shop is that you can get immediate service to resolve any complaints.  Most internet stores do not carry manufacturers warranties, despite what they may tell you.  You DO NOT want to get a regulator without a factory warranty.

Alan, I hope this information will allow you to deal with your breathing anxieties and enjoy your trip to Maui (I'm jealous!!)

Happy Diving!!
Mike Giles
Mike's Dive Center
mikescuba.com