It's a common sight. A diver is about to enter the
water when suddenly his octopus or even his primary
second-stage suddenly does an impression of a jet
engine at the end of a runway just prior to take-off. The
sudden roar as gas at 1000 psi of pressure rushes out
uncontrollably often precipitates the diver to grab the
offending item and shake it violently, or even frantically
smack it on something hard. All he needs to do is put
his thumb over the mouthpiece , but instead, he usually
hastily fumbles with the tank valve to solve the problem,
even if it means a substantial part of the tank-fill is lost.
Another more serious situation can arise if a secondstage
suddenly starts to free-flow during a dive. This is usually associated with icing of the regulator during a
dive in cold freshwater. (Seawater around most coasts
rarely gets cold enough.) If the water is less than 50
degrees, there is a risk of freezing, so this can happen at
many freshwater sites at almost any time of the year.
For a competent diver, this should represent nothing
more than an inconvenience. On the other hand, this
often results in a fast or uncontrolled ascent, with all the
hazards to health implicated in such an action. But there
should be no reason for a diver so affected to panic . . .
To read the rest of John Bantin's story about how divers can
keep control during a free-flow situation, click here to go to
our blog page, www.undercurrent.org/blog, then click on
"Anatomy of a Free Flow."