Bookshelf: SEALAB

SEALAB – Ben Hellwarth


In the 1960s the US Navy developed three undersea habitats, in order to experiment with saturation diving and to explore the possibility of humans living on the ocean floor. Of necessity, any group of people engaged in this pursuit would be separated from life on the surface, in some cases by days or weeks of decompression obligations. SEALAB I, II and II were progressively deeper and more complex habitats. Developing them was a technical challenge that led to many advances that we benefit from today. The experiments also provided an opportunity to study the psychological and physiological effects of isolation, and of long periods of breathing mixed gases under pressure.

The SEALAB experiments took place during the same era as the efforts by NASA to put a person on the moon, and received far less attention. Jacques Cousteau was interested in the project, and himself experimented with underwater habitats called ConShelf I, II and II. These habitats were far better publicised than the US Navy’s efforts, even though their aims were more modest.

Author Ben Hellwarth does not confine his attention to the habitats, but also provides a fairly detailed history of decompression theory and diving history. Like Neutral BuoyancySEALAB might provide a relatively painless introduction to dive theory for Divemaster candidates. In fact, this book reads like a thriller at times! Some photographs from the SEALAB projects are available on the US Navy website, and in this slideshow. To our modern eyes, the clunky and primitive appearance of some of the gear is a reminder of how pioneering the now 60 year old work to allow humans to live and work in the sea was.

If you’re interested in the history of saturation diving, I recommend this article, which covers some of the ground that Hellwarth does in SEALAB. If you want to see it in action, check out Pioneer (fictional movie based on actual events) or the series Deep Sea SalvageYou should also check out this article by Hellwarth, entitled The Other Final Frontierand this podcast/radio show. If you are EXTREMELY interested in this subject but don’t want to read a book, try out this hour-long lecture video by Ben Hellwarth.

Experiments with underwater habitats are ongoing.

Get a copy of SEALAB here (South Africa) otherwise here or here.

Movie: Pioneer


In the late 1960s, massive oil and gas deposits were discovered in the North Sea, transforming Norway into one of Europe’s wealthiest nations. Pioneer depicts some of the early, feverish oil-related activity during the 1970s. The Norwegians needed to build a pipeline to bring the oil to land from depths of up to 500 metres. Lacking the technical expertise – particularly with respect to the underwater work that must be done by saturation divers – they bring in American assistance.

Norwegian divers (so-called “pioneer divers“) dived to depths that are now considered unsafe, even for saturation divers, and a group of them have sued the Norwegian government for compensation for damage incurred during their careers in the early days of the oil boom. Pioneer tells the story of Petter, a Norwegian diver who is present during a diving accident and embarks on a search for the cause, believing that human error was involved and that someone must take responsibility.

I enjoyed the film enormously, but most of the reviews I have read found it a bit turgid. The milieu is evoked with incredible attention to detail, including the awful 1970s moustaches and unfortunate hairstyles. The dialogue is in both Norwegian (subtitled) and English. It is beautifully filmed, with clever camera work mimicking the limited view that the divers have while working underwater and in the saturation chamber. The underwater scenes are excellent, reminiscent of those in For Your Eyes Only (I’m joking – they genuinely are extremely convincing and quite magnificent). Tension is maintained throughout, and the action takes places over a fairly short period of time.

You can get the DVD here (South Africa), here or here.

Movie: Men of Honor

Men of Honor
Men of Honor

Men of Honor is a contender for the movie with the most stellar cast that you’ve never heard of. Robert de Niro, Cuba Gooding, Jr, and Charlize Theron star in this ficitonalised account of the life of Carl Brashear, the first US Navy African American master diver.

Brashear grew up in poverty and enlisted in the navy 1948, an era during which race relations in the United States were not that dissimilar to race relations in South Africa. He showed dogged persistence in surmounting obstacles far greater than those placed before his white classmates, and successfully qualified as a navy diver in 1954.

Navy divers performed challenging underwater work, retrieving lost nuclear warheads (this happened more often than you’d like to know, during the dawn of the nuclear era), salvage work, repairs to ships, demolitions, clearing harbours, and maintenance (all underwater, of course). In many respects it is much like commercial diving, but with a combat element to it. The underwater scenes are reasonably convincing (except for one shot with a submarine) – suspiciously clear water being my chief complaint, but realism doesn’t always make for good viewing!

This is a highly simplified account of the life of a complex character, but Tony and I both enjoyed rooting for Brashear to overcome the odds and wipe the smirk off various antagonistic establishment characters’ faces. This always happened (no surprises there). Charlize Theron’s role is quite peripheral and, frankly, somewhat confusing. Robert de Niro is always wonderful.

You can get the DVD here if you’re in South Africa, otherwise here or here. It wouldn’t be a total waste of an evening, specially if you had popcorn to hand…

Newsletter: Swelly winter

Hi divers

Weekend diving: No dives planned. Pool on Saturday!

Checking out some saturation diving equipment at the DAN Day
Checking out some saturation diving equipment at the DAN Day

Last weekend we attended the DAN Day at Unique Hydra (a company that makes and markets commercial diving equipment) and as always the speakers and the topics were exceptionally good. DAN stands for Divers’ Alert Network, and they provide medical insurance for divers over and above what your medical aid will cover, as well as incredibly useful advice and guidance via their hotline, staffed by diving doctors. Twice a year they arrange a day of diving and health related talks and a tour of an interesting facility – the next one is on 2 August and I highly recommend you attend. We’ll remind you closer to the time.

The photo above is from the DAN South Africa instagram feed! We are standing in front of a huge structure that will be built into a ship, enabling saturation divers to live and work in a pressurised environment for weeks on end.


No launches are planned this weekend. Saturday starts off really windy and the wind picks up dramatically during the day. On Sunday, it blows even harder and a 5 metre swell arrives. I have pool training so will be spared the grumpy sea. Its a pity as the visibility is currently really good. We’ll hold thumbs for next week!


Tony Lindeque
076 817 1099

Diving is addictive!

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Article: Wired on rigid dive suits

I want one of these. Wired published an article in January about a rigid diving suit built by Nuytco Research, called the EXOSUIT. The inside of the suit is maintained at surface atmospheric pressure, obviating the need for lengthy decompressions after working at depth. The suit is incredibly flexible, which sets it apart from many previous efforts to build such suits. The visual field is excellent, and if you’re not sold on the thing already, it has thrusters… So it’s like an underwater jetpack.

The EXOSUIT from Nuytco
The EXOSUIT from Nuytco

Read the full article here, or check out the full specs of the EXOSUIT here.

Article: Randall Munroe (xkcd) on swimming with spent nuclear fuel rods

Randall Munroe, the man behind the xkcd cartoons that light up my world, blogs about ridiculous and unlikely scenarios at What If? He uses his physics knowledge and some wide-ranging research to answer hypothetical questions that couldn’t be answered with an experiment or by direct inference from actual events.

Scenario 29 answers the question:

What if I took a swim in a typical spent nuclear fuel pool? Would I need to dive to actually experience a fatal amount of radiation? How long could I stay safely at the surface?

It turns out that, as long as you stayed far enough away from the fuel rods while in the pool, you’d probably experience a lower dose of radiation than you would walking around outside the pool. The amount of radiation in the water halves with every seven centimetre increment away from its source. Divers are actually employed to perform tasks and service the equipment in these pools, so it can’t be that dangerous. There is a description of an accident, however, and it makes fascinating reading (follow the link too).

Read the scenario here.

Series: Deep Sea Salvage

Deep Seal Salvage
Deep Seal Salvage

The History Channel series Deep Sea Salvage ran for one season of six episodes in 2009. The series follows the activities of salvage teams employed by Bisso Marine, a family owned salvage company that has been operating along America’s Gulf Coast and (more recently) beyond, for over 100 years.

The first few episodes involve the land and surface-based salvage of some partially sunken vessels in the Mississippi River and surrounds, and a number of barges pushed far inland by a storm surge. I can’t prove it, but I strongly suspect that much of the mayhem that the salvage teams are required to fix occurred as a result of Hurricane Katrina.

Later episodes deal with salvage divers who venture (alone) 100 metres below the surface of the Gulf of Mexico to shackle giant chains to a wayward oil rig leg, or into murky, fast flowing river waters to determine whether a wrecked barge still contains toxic oil in addition to what’s already spilled out and polluted the river. The diving shown isn’t saturation diving.

The show is edited (I think) to make the action seem quite rapid and to take place over short periods, but in some cases there must be a lot of waiting – for weather, gear, support – involved. Tony and I would have liked to see more detail about the dive planning, the gas mixtures used (for the deeper ones helium seems to be involved, because the divers’ voices over the radio were hilariously squeaky) and the logistics of dealing with potential decompression sickness while on a crane barge out at sea. The show isn’t really about that, though; it’s concerned with the work the divers do underwater, but not so much how they get there and back. We were gripped by the dive footage, despite this.

Everything is enormous. The barges and oil rigs are colossal. The winches, cranes, chains, blocks and pulleys, ropes and other equipment such as inflatable bags (large enough to rest a barge on top of a few of them) are all giant-sized. Working with such massive gear requires planning; one can’t quickly pop back to the office to pick up a winch one has left behind, or quickly pick up a chain and move it out of the way of an earth moving machine. Out at sea the constraints are even more severe. Most of the jobs covered in the series were so mind-boggling to me that I would have ordered the vessels scrapped – one can’t even imagine that it’s possible to remedy some of the situations shown. And yet somehow it is, and the Bisso teams do.

Something else that makes this a fine series to watch is that one of the slightly senior salvage team members is called “Lunchbox”. You read that correctly.

You can buy the DVD box set here.

Article: New York Review of Books on commercial diving

Nathaniel Rich writes for the New York Review of Books about commercial diving. Rich is a novelist and essayist, and the article is a fascinating, fast read. He traces the history of some early efforts to dive to 1,000 feet (about 300 metres) in the early 1960’s. The dive did not go as planned.

Hannes Keller and another diver travelled to the intended depth inside a diving chamber designed by Keller, which could be exited and re-entered to complete the dive. Keller climbed out of the chamber into the water carrying a Swiss and American flag to plant on the continental shelf.

But as soon as he exited into the dark water, the fabric of the flags became entangled with his breathing hoses. He couldn’t see. It took him two minutes to free himself of the flags, at which point he returned to the diving chamber, exhausted and dizzy. In his confusion Keller didn’t realize that one of his swim fins had become stuck in the hatch, preventing it from closing properly. When he figured out that his special mixture of gas was leaking, and that there was not enough to sustain them for the ascent, he switched to regular air, and the two men instantly passed out.

Keller’s companion in the diving chamber died of decompression illness upon surfacing, and a support diver who attempted to assist Keller and his companion on the ascent also died. The widow of one of the dead divers committed suicide some weeks later.

Despite the awful human toll of this proof of concept, Keller’s theories about mixed gas diving and decompression were validated, and as a result, today’s commercial divers are able to operate at depths of up to about 300 metres, working especially for oil companies who have rigs and pipelines resting deep on the ocean floor. Rich explains saturation diving, and concludes with details of the risks faced by commercial divers:

This makes commercial diving the third-most-dangerous occupation, behind fishing and logging. Very few of those deaths can be attributed directly to decompression-related illnesses. Instead divers are threatened by the same hazards that confront all occupations that require the use of heavy machinery, only a diver’s risk is multiplied by the dangers of performing the work underwater, with limited vision, while encased in a diving suit.

Read the full article here.

Bookshelf: Deep Driller

Deep Driller – Henry F. Merritt

Deep Driller
Deep Driller

I started reading this book by accident – it’s actually a novel, which I didn’t realise, and I’m very picky about my fiction reading. The author has had a long career in oil exploration around the world, and this is his first effort.

The book concerns (and is set on) a giant drilling platform in the North Sea off Scotland, called Deep Driller. A terrorist plot by a group of Scottish separatists threatens the rig with destruction. As the action takes place in the 1970’s, the crew on board must rely on helicopter couriers, telex and radio to communicate with the mainland. A threatening storm complicates matters further.

For a book of this length (about 150 pages) the cast of characters is large, and I found it hard to keep track of who each of them was as a result of jerky transitions from one viewpoint to another. Merritt builds up the tension quite nicely, but the book ends very suddenly and left me feeling that much more could have been done with the original plot idea. Hammond Innes would have a field day developing the story line a bit more and for several hundred more pages. Parts of the dialogue were tiresome to read as the author insists on reproducing in print the accent of every multinational crew member.

Despite what I felt were flaws in pacing and plot development, the insights I received into the oil exploration business were intriguing. I did enjoy the descriptions of life on board the drilling platform – something the author is very familiar with and which has fascinated me since I was a child. It is in these sections, describing the process of drilling a well, or the layout of the drilling platform, that Merritt really comes into his own. I hope that he makes future efforts to write on these subjects, as there is an air of mystery surrounding this most lucrative and essential economic activity that has ties to geology, oceanography, and a host of other specialist areas. This book also equipped me to understand the Deepwater Horizon oil spill a lot better from a technical point of view.

Buy the book here if you are in South Africa and here if you’re not. If you want to read it on your Kindle, go here.

So you want to be a commercial diver?

Metro Rescue Divers setting up at Hout Bay Harbour
Metro Rescue Divers setting up at Hout Bay Harbour

I sometimes get queries from people who want to become commercial divers, and be able to perform specific tasks such as underwater welding. The courses I teach are PADI recreational diving courses, and are for people who want to enjoy the ocean but not necessarily work in it. A sport or recreational diving certification such as the PADI or SDI Open Water course is usually a prerequisite for starting the Class IV (entry level) commercial diver course. I can help you with that – click here for more information!

You need a commercial diving qualification in addition to the Open Water course in order to work as a commercial diver. There are a few commercial diving schools in the Western Cape that could help you:

There is also Professional Diving Centre (PDC) in Durban if you’re from further afield.

Whatever one you choose, make sure they’re IMCA registered. This is the regulatory body for commercial diving and marine contracting.