Navy Experimental Dive Unit:
Testing Pools, Chambers Put Humans, Gear to the Test
On a high ledge in the corner of a 12-foot deep test pool containing some 33,000 gallons of 40-degree water sits an unfinished Sudoku puzzle.
Navy Master Diver Ryan Langley, NEDU operations department master diver, said he and his team are charged to test human biometrics, glean vital data points, and assess dive gear for form, fit and function before it's sent out for fleet use.
"We want to have a controlled environment here before we put everyone in the unforgiving mercy of the ocean," Langley said. "It's a safe environment, it's a quick exit and we have a treatment facility right here so if something does come about, we can treat it immediately."
Langley said the operations team can adjust the water from a glacial 35 degrees Fahrenheit to a boiling 105 degrees Fahrenheit.
And, as some of the recreational objects beneath the surface might suggest, test subjects submerged for six-to-seven hours pass the time to beat boredom and enjoy creature comforts while the NEDU team scrutinizes their core temperature and vital signs, as well as dive gear that's passed the review phase.
"We have some things down there to keep them busy, some underwater football, we also have a [movie] projector ... and they can hear through a transducer underwater," Langley said. "So right now, I don't know if you can hear it, but they're actually watching 'Elf.'"
Other apparatus includes a horizontal exercise bike with RPM monitoring equipment to simulate diver output on the bottom during a working dive, Langley said.
Still, even the sharpest divers can face daunting conditions during experiments.
"When you're at the bottom of this pool for a very extended period of time, your mind does start to play tricks on you, and you get very bored," Langley said. "Sometimes the elements may get to you, so you have that constant thing in your head, 'Do I want to get out now? Do I want to stay down here? What will everyone else think about me?'"
Having that perseverance to get through a dive, even though it's not the most fun or comfortable thing at the time, plays a lot into what we do here." - Navy Master Diver Ryan Langley
As a 12-foot pool cannot be pressurized, the NEDU team sometimes conducts saturation dive tests to analyze deeper dive conditions while stanching decompression sickness in their experiment participants.
That's when the behemoth, five-chamber, self-contained, temperature and pressure controlled ocean simulation facility comes into play.
Navy Diver Senior Chief Petty Officer Eric Wilson, NEDU command master diver, said the OSF is the most complex and largest saturation facility in the Defense Department's inventory. It was developed in the late 1960s and installed at the NEDU in the early 1970s before being commissioned in 1975.
Our depth capability is 2,250 feet, we did saturation dives up to 1,800 feet in 1979, and we continue to do saturation, cutting-edge diving for the Navy all the way to today." - Navy Diver Senior Chief Petty Officer Eric Wilson
And once the highly-seasoned divers arrive to the NEDU, they'll spend a good 6-12 months training together in preparation for extended time in very close quarters.
"The qualification process is probably like no other in the sense that we do saturation diving [and] you are sometimes in the chamber for 5, 6, 10 or 12 days," Wilson said.
To mitigate that, Wilson said the NEDU team builds a "sat" team in which the test subjects physically train together, eat together, and live closely during a work-up cycle ranging from 1-3 weeks, depending on the dive series.
An institutional review board proposes a protocol based on a fleet requirement to decide whether a test calls for human subject research, equipment research, biomedical research or some combination thereof.
"It comes down to a roundtable decision," Wilson said. "But the bigger picture is we are putting a stamp as a Navy Experimental Diving Unit for a piece of gear that's going to be used out in the fleet by other Navy divers, Navy Seals, explosive ordnance disposal techs, so safety is our number one concern."