Regulator problems?


</>There's no question that the most critical item in a diver's ensemble of dive equipment is the regulator. Without air to breathe, a diver's time underwater is limited to only a minute or so at best.

</>While today's modern regulators are well-engineered and highly reliable, divers do occasionally experience problems with their breathing apparatuses. Conditions such as free-flow, hard breathing, inhalation of highly moisture-laden air or even an abrupt stoppage of airflow can occur. The question becomes: What problems are most likely to occur, and what can we do to prevent them and deal with them?

</>A recent online survey by Scuba STAR Network took a look at common regulator problems experienced by divers and at issues such as regulator care, maintenance and safety checks. The more than 150 divers responding to the survey tended to be a rather experienced lot: About a third of the respondents were instructors with more than 1,000 lifetime dives. Preliminary results of the survey reveal several interesting facts that can help us prepare for problems with regulators and prevent them from occurring.

 

 

 

Common maladies


</>Divers responding to the survey report a low incidence (3 percent) of regulators failing to provide air, thus highlighting the reliability of modern regulators. Twenty-nine percent of divers reported that they have never experienced a problem with a regulator while diving, and those who have experienced problems reported that problems occur rarely (i.e., in fewer than one of 10 dives).

</>Seventy-one percent of divers reported that they have experienced regulator problems at least once while diving. Table 1 lists the percentage of divers who reported experiencing the various problems identified in the survey. The most common problem is that of a free-flow condition, with nearly half the respondents reporting they had experienced this problem.

</>The next most common problem is wet breathing, or water entrained (carried into) in the breathing air; 28 percent of reporting divers experienced this problem. Mouthpiece failure or separation is next on the list, with 21 percent of the divers reporting this problem.

</>As anecdotal evidence suggests, what might appear to be a minor oversight can evolve into a serious condition or even a full-blown emergency. Consider the following incident report.

</>"In a predive check I noticed the tie wrap was missing from my mouthpiece. Not having a spare, I made the dive without it. Near the end of the dive, we entered a shallow cave. My buddy signaled low air and turned to leave. As I turned, the regulator mouthpiece came free from the regulator, but since the mouthpiece was still in my mouth, I thought the regulator was, too. I inhaled, took in nothing but water, cleared, took a second breath of water, and then chased my buddy.

</>"We made contact outside the cave entrance and began to share air. During the initial exchanges, we were drawn to the surface by heavy surge. Very large waves at the surface slammed us against the rocks, resulting in my buddy being knocked unconscious. I dragged him away from the rocks, he regained consciousness, and we safely exited. I carry spare tie wraps in my kit now."
 

 

Strategies for prevention


</>Perhaps the most important strategy for avoiding regulator problems is to conduct a thorough predive inspection and function check of your regulator. Divers are generally faithful in the conduct of such inspections and checks.

</>While only 76 percent of the responding divers reported that they inspect their regulators before most or all dives, 92 percent of divers surveyed reported they performed a function check either for all dives or most dives.

</>When it comes to the specifics of the regulator inspection and function checks, we see broad variations among divers. Table 2 shows the percentage of divers who reported they had performed the various checks and inspections.

</>Not surprisingly, most divers perform the more obvious checks, such as verifying that the regulator delivers air, that the first stage doesn't leak and that the purge button functions. Relatively few perform some of the other simple checks, such as verifying that the inlet screen is not blocked. This is an uncommon condition, but it is one that can result in failure of the regulator to deliver air. Relatively few divers perform an inhalation test with the air turned off to verify the seating and condition of the diaphragm. A split or cracked diaphragm could result in entrained water, or a failure of the second stage.

</>Divers responding to the survey also pointed out a few additional items that can help ensure the integrity of the total breathing air system. For example, many regulators have adjustments that the user can make, and these should be checked regularly. Respondents also pointed out the importance of checking the O-ring on the pillar (cylinder) valve, the zero reading of the submersible pressure gauge and the function of the alternate air system after entering the water.

</>The good news is that divers can avoid the most prevalent problems through careful predive inspection and preventative maintenance. As part of the predive check, divers should closely inspect the mouthpiece to ascertain its condition and security. More than one in five divers reported they routinely omitted such procedures. Divers should also perform an inhalation function test to verify the condition and seating of the second-stage diaphragm — a procedure followed by only 56 percent of respondents. This step can identify a problem leading to entrained water and second-stage failure

 

Routine maintenance

</>An interesting finding of the survey is that divers tend to keep their regulators for a relatively long time. The average age of regulators used by the respondents was about five years, with a range from just a few months to more than 15 years. The largest percentage of divers — about three-fourths — reported that they purchased their primary and secondary regulators at the same time.

</>Divers who plan to use a critical life support item for an extended period of time should invest in routine and preventative care and maintenance to ensure the reliability of that equipment. For example, checking and adjusting the intermediate pressure and other vitals could help prevent some free-flow situations. Eighty percent of the divers responding to the survey reported they addressed this yearly through professional maintenance of their regulator or per manufacturer recommendation.

</>A few divers with the tools and knowledge to do so reported that they maintain their own regulators. About 5 percent reported that they have their regulators serviced only when a problem develops.

</>When it came to caring for their regulators, divers seemed to recognize the importance of careful handling and routine cleaning. Most divers reported that they rinse and/or soak their regulators after every day of diving (46 percent) or after every dive (26 percent). A smaller number (17 percent) reported rinsing or soaking their regulators after every dive trip.

</>Failure to take steps to remove or prevent salt deposits can present problems. Reported one respondent: "On one occasion my second stage had seized due to salt deposits, after not being rinsed properly. I was unable to start that dive but was able to remedy the problem by leaving the second stage immersed in fresh water overnight."

 

Ready for trouble


</>Dealing with a regulator problem at depth can be stressful. About 15 percent of the divers who reported having regulator problems also reported that they had at some point experienced anxiety or panic as a result.

</>Regardless of how thoroughly we inspect and check our regulators, the potential exists that we could experience a problem that requires a quick solution: That means having an alternate air source available or a buddy close enough to quickly share air.

</>All divers are not equipped with the same type of alternate air system (see Table 3), so having a working knowledge of the various systems, and especially those of our buddies, can be important when trouble arises.

 

Taking aim on safety

</>A regulator problem that occurs underwater can leave us struggling to catch our breath. By adopting an attitude of professionalism and taking the proper steps, we can avoid many of the troubles that might come our way.

</>As one diver sums it up, "I have [my regulators] serviced at our club shop by a professional service engineer, and that gives me peace of mind when I dive. Predive checks on the air delivery system are also vitally important to me. I believe these were designed to keep you alive underwater, so you better look after them."

</>In fact, it might be possible to reduce the number of regulator problems that divers experience by 50 percent or more simply through regular care and maintenance and thorough predive checks. As for those problems we can't foresee and avoid, at least we can be ready to deal with them.


</>RICK LAYTON is an experienced diver and longtime DAN Member who writes regularly on the subject of dive safety. He invites DAN Members to visit http://www.scubaSTARnet.com to participate in future safety surveys and to report equipment, training and procedure-related diving incidents.