The Magazine for Underwater Professionals

Sep/Oct 2016


Development of a global hyperbaric rescue service - part 5

In the fifth of a series of articles on hyperbaric rescue, Brian Redden, director of global hyperbaric rescue services at UK-based JFD, takes a look at the launch of the HRC or SPHL

The SPHL is housed inside a conventional lifeboat body

In parts one to three, I reviewed the general history of the modern commercial diving industry and how hyperbaric rescue has developed to date. In part four, I looked at current thoughts on the recovery of a SPHL if it were launched in a real emergency.

In this article I will discuss the practical issues to be faced in the event of a hyperbaric lifeboat launch. However, before then, let me get the terminology correct and use the diving industry standard generic term for a hyperbaric lifeboat, which is hyperbaric rescue unit (HRU).


I should start by reviewing the differences between the two types of HRU in service within the commercial diving industry around the world today. These are the HRC (hyperbaric rescue chamber) and the SPHL (self-propelled hyperbaric lifeboat), also called an HLB (hyperbaric life boat) by some diving contractors. Both of these HRUs consist of an approved PVHO (pressure vessel for human occupancy) with external coatings of insulation and buoyancy material. In the case of the HRC, the PVHO is simply mounted inside a protective steel girder frame, whilst the SPHL is housed inside a conventional lifeboat body. Both types of HRU will have emergency HP (high pressure) ‘onboard gas’ supplies of helium and oxygen and have EPIRBs (emergency position indicating radio beacons). Whilst both are also fitted with carbon dioxide scrubbers, this is really where the similarity ends.


The modus operandi for the HRC is for this to be undocked from the dive system, then either tilted and slid down a ramp into the sea or lifted outboard by a ship’s crane and lowered into the sea. The HRC has no real life support system for the divers. It is dependent on being picked up by a rescue vessel as soon as possible after launch, then plugged into a LSP (life support package) to establish control of the internal atmosphere by heating or cooling it and removing CO2 and humidity, until such time as either the HRC is mated to an HRF (hyperbaric reception facility) and the divers transfer into its living chamber to be decompressed, or they are decompressed in situ in the HRC.

The main difference between the HRU types is that the SPHL is effectively a ‘boat’ after it is launched, and will be operated by its crew (usually of four members) from the DSV/rig/ platform and at least one of these will have a bosun’s ticket. One of the crew is also usually an LSS (life support supervisor) from the offshore dive team. The other very significant difference is that the SPHL has a marine engine which can not only propel it at speeds of up to six knots, but drives the onboard life support system which is designed to maintain the internal atmosphere (controlling temperature, humidity, CO2 levels, etc.). Being able to make way under its own power and having the capability to maintain life support gives the divers in the SPHL a significantly greater chance of surviving than their counterparts in the HRC, if they are not picked up very quickly.


So, under what circumstances will a saturation diving superintendent order his divers into their HRU and ‘cast them adrift’? The short answer is when it is his last resort and there are no other options. Whether the dive system is on board a DSV, a production platform or a drilling rig, “abandon ship” is the very last resort and is ordered only when the person in overall command has concluded that the vessel or installation is in such dire straits that the personnel on board are in mortal danger.

  • Inside an HRC

On being ordered to abandon ship, the dive supervisor will get his divers into the HRC or SPHL as quickly as possible. The worst possible scenario is for the abandon ship order to be given whilst the bell is still down, either with divers still out working or in the process of the bell being recovered to deck. In this case the dive crew will rely on the drills and emergency procedures they will have practised over and over (we hope!) to achieve fastest possible bell recovery and diver transfer into their HRU.

The same general HRU launch procedure will be followed whether it is an HRC or SPHL, but thereafter it could be very different for the respective occupants because of the differences between them previously described.


Once all divers are in the HRU and they have confirmed their inner door is closed and dogged, the dive supervisor or LSS will drain pressure from the trunking and the deck crew will unlatch the HRU from the dive system. Most HRCs sit on a ramp which is tilted to slide it overboard into the sea, but some need to be lifted outboard by the ship’s crane then lowered into the sea. Virtually all SPHLs have a launch and recovery system by which the unit is lifted or swung outboard, lowered into the sea and unlatched free. In an HRC the divers are then on their own because it is simply a pressure vessel with insulation and buoyancy material around it, inside a protective steel girder frame – with no means of propulsion. A SPHL will usually have a four-man ‘ship’s crew’ who will start the engine and move the HRU away from the scene to avoid possibly being damaged by whatever catastrophe overcame the DSV or installation.

The scenario for the occupants of the HRU is then going to be very different depending on whether they are in an HRC or a SPHL.



For the divers in an HRC, local conditions are critical. If they are in a high-temperature region and it is daytime, they probably only have a very few hours before they will effectively be ‘boiled’. If they are in cold climes they have probably got a little longer, but if their HRC is not picked up within a few hours they are likely to freeze. In either case, it is critical that the HRC is recovered to the deck of a vessel in the shortest possible time and a LSP connected to provide them with life support.

Depending on the HEP (hyperbaric evacuation plan) of the dive contractor, the divers will either be decompressed in the HRC or it will be transported to a port where their nominated HRF is located, where it can be docked on and the divers transferred for decompression. However, in those regions of the world where HRCs are still used, it is probably still pot luck whether the divers make it or not. It is a fact that there are HRCs being used that have never had their LSP’s trial hooked up. Even worse maybe, there are diving systems with HRCs and a nominated HRF which have never been trial fitted together!

But let me go back to just after the HRU launch. Whilst the divers in a SPHL will be much better off than those in an HRC, their chances of survival still differ greatly depending on the part of the world that they are operating in and the diving contractor that they are working for. In the North Sea and other regions where IMCA and IOGP guidelines are adhered to stringently, they start off with the best possible chance of survival. They will have regularly practised ‘abandon ship’ procedures, their SPHL will have had its LSP trial connected to ensure everything works and the life support system functions correctly and it would have been trial fitted to its nominated HRF to make sure that if ever ‘launched in anger’, they will have the confidence that everything fits. Also ‘SPHL launch’ exercises will have been conducted to run through the whole emergency response scenario and to ensure all the minutiae have been considered and allowed for.

  • Inside a SPHL

In those regions where only lip service is paid to the operational guidelines or where they are just ignored, things will be very different. In India for example, where saturation diving is being conducted 365/7 offshore Mumbai, many don’t have any HEP provisions and rely on other saturation diving vessels they have in the field to dock a launched SPHL onto. However, many of these have not had any trial fits to ensure that it is possible.

When I looked into how much saturation diving was taking place in the Mumbai High oilfield and what hyperbaric evacuation facilities existed there, I learned that in the 2015/16 summer working season there were at one point seven DSVs undertaking saturation diving and not one operating HRF in the region. (NB: It is the case that one diving equipment manufacturer has an HRF in its Mumbai base, but as far as can be ascertained, no diving contractor active in the Mumbai High oilfield during the 2015/16 summer working season had contracted it to cover its diving operations and no trial fits of SPHLs or HRCs to it had been undertaken.)


So what will conditions be like for the divers in a launched HRU. Firstly, it must be understood that once they are in the HRU any medical care they can get is minimal and dependant entirely on having qualified and experienced DMTs (diving medical technicians) in the dive team. It is to be hoped that on entering the HRU the marine crew and every diver will have been given seasickness pills and possibly patches to wear, but even these basic measures are not standard practice across all diving contractors. Virtually all HRUs are fitted with ‘Recaro’ type seats with head and neck protection and four-point harnesses, but seasickness will be a major factor and could feasibly incapacitate everyone on board in a relatively short period of time. It is therefore imperative to get the HRU to a place of safety as fast as possible. Communication will have been established between the marine crew and divers and it is important that this dialogue is kept up so that those inside are updated on developments and their morale maintained. The marine crew will also have established communication with the coastguard.


And that is basically it, until the HRU is either picked up, towed in or makes its own way to its port of safe haven and HRF. Whilst I could discuss many other potential means of ensuring that divers get the best chance of survival in future, the fact of the matter today is that for our dive team now in a launched HRU, they have a very finite period in which to be rescued. In the HRC that is a matter of hours. In the SPHL, it is a matter of tens of hours – whatever the guidelines say about them having up to 72 hours life support onboard!

The BGR story - tales from nearly 50 years in the diving industry
  • Brian Redden

It was late 1974 and I had moved my family to Malta to live whilst I worked in Libya. The job was for a small UK diving company which had somehow managed to get a contract with Occidental Petroleum to provide the diving support for its oil export terminal at Zueitina on the Mediterranean coast of northern Libya, east of the Gulf of Sirte. At the time, something like 1.6 million barrels of oil per day were being pumped there through a 40-inch pipeline from the production wells some 125 miles south in the Sahara desert.

I initially took the job because it was pretty zoomy in many ways. We could live in Malta and give our three-year-old son (and loads of family who visited us) the experience of being in a foreign place with sunshine every day. The job was in Libya, just a 30-minute flight away from Malta. The work of maintaining oil loading systems was something I had not done before and the carrot was that after a few months as a diver, a supervisor job was promised.

We worked a two-week on and one-week off routine, crew changing by commercial flights from Malta to Tripoli and then by the Occidental Petroleum (known as Oxy) Fokker F27 Friendship airplane down into the desert. The daily flight flew the first 150-mile leg south-west from Tripoli down into the desert to the oil production wells site, the second leg 125 miles north to Zueitina and then the final leg some 95 miles east back to Tripoli.



Usually it was quite a boring flight because one bit of desert looks much like the next, but one day it livened up when we got hijacked. The pilot was a really laid back Texan who had flown combat missions in Vietnam. His uniform (from the top) was a black Stetson, aviator Ray Bans, flower embroidered white cowboy shirt with his captain’s four gold bars shoulder epaulettes, tight black jeans and tooled black cowboy boots. He came on the speaker with his slow drawl and told us: “Don’t be getting alarmed guys, but the ‘raghead’ who just came into the cockpit has a pistol on me and is pointing to a map of Tunisia, so I guess we have us a hijacking in progress here.” He then went on very calmly to tell us the hijacker obviously did not speak English, that he had given the man a headset to put on so he could hear everything being said on the radio (but didn’t know it was also being broadcast to us in the back), that he had flicked on his ‘transmit to base’ button so his flight controller in Tripoli could hear everything being said, and that he was having a “sign language and point at the map discussion” with the guy to agree where he wanted to fly to. All this was said over the cabin speaker, being heard by us and by Oxy flight control, who also spoke Arabic and quickly had a dialogue with the hijacker to learn what his demands were.

It transpired that the man was an illiterate labourer who thought he would have a better life in Tunisia and that he would be able to simply hijack the Fokker then get off and away when it landed there. Between the pilot and the Oxy ATC (air traffic controller) guy they persuaded the chap that the flight had been diverted and was heading to the nearest air strip in Tunisia where he could get off. What actually happened was the flight went to another Oxy base in the desert which had a Libyan Army attachment. When we landed, the man put his gun into his left hand then shook all of our hands with his right hand before he disembarked. Of course, before he had even reached the airstrip arrivals shed he had been surrounded by soldiers who materialised out of the sparse undergrowth and overwhelmed him. The last we saw of him, he was being bundled into a battered old ex-UK Army Landie. And not a shot was fired.


In Zuietina we lived in an ‘expats’ camp enclosure made up of portacabins about a mile inland from the small port. It was great fun because some of the Oxy terminal guys had been there for three or four years and had beer-making down to a tee. Their product was a very tasty hoppy beer that was probably about 7% proof and was lethal. The camp had a restaurant serving food around the clock and an adjacent recreation room with pool table and movie screen. It was very civilised and for expats only. No beer or liquor was allowed outside of the camp as the country was muslim and Sharia law was strictly enforced.
The contract our employer had was for provision of all diving services needed to maintain the six oil loading terminals a mile or so offshore. Oil tankers would come in, drop anchor, then take onboard a flexible hose which would be connected and then oil pumped until there cargo volume had been reached. They would then disconnect and sail away. This was happening around the clock on each of the six terminals. I believe that when on maximum production there was some 1.6 million barrels of oil per day being exported from the terminal.


We did everything that needed doing underwater around the terminal, from major jobs like changing out a complete SBM (single buoy mooring) installation to smaller routine tasks like hanging out flexible floating hoses and we even did a bit of wet-welding when a tanker anchor dragged over one of the SBM supply pipes in a storm and buckled it. The weld wasn’t pretty, but it sealed the leak, stopping the drip of crude oil that floated up to the surface and caused a slick that could be seem from miles away. The diving conditions were amazing, usually more than 100 feet visibility and invariably flat calm. Our employer was supposed to provide a boat to dive from, but had been given dispensation to use a 60-foot Oxy-owned tugboat until he could get his dive boat on site. We drove this tugboat ourselves and I remember many happy hours ‘skippering’ her back into port as the sun was going down. A great experience.

On one SBM we had a resident grouper who had been nicknamed Big Jack and was about the size of a Mini car. He would come up behind a diver working around the SBM base and just nudge him until the poly bag of scraps of food he had taken down for him was shaken loose.


Our dive crew was eight divers plus one supervisor and we worked 12-hour day shifts seven days a week. When I first joined the job all the divers were British but because they were cheaper to employ, the company gradually replaced Brits with Maltese. In those days you could basically talk your way into a diving job, then if you survived on-site and managed to do the work, you got accepted. It would probably be another 10 years before proper diver qualifications and diver logbooks became mandatory. We had a great supervisor called Garth Dance. He was probably the best air dive supervisor I have ever worked with and I learned a lot from him. He is retired now, but just got remarried. So if you read this GD, all the best from me for the future.

Our employer had bought his dive boat and the first we heard about it was when he advised Garth it was being outfitted in UK and would be sailed down by a “Libyan delivery crew”, taking an estimated two weeks to get to Zueitina, steaming only in daylight hours, port hopping down from UK through Biscay, Gibralta, around the north Med coast then the crossing down to Libya. The vessel was an ex-Royal Navy ‘Bar boat’. Called Francis A Holmes, she was built in 1944 and was originally named HMS Shipway. She had served through the years as a wreck clearance vessel and by 1974 was being used for cable laying.


We (Garth) had reservations about the boat before we even saw her. She was steam driven and we knew her type consumed huge amounts of fresh water and fuel oil per day whilst managing a maximum cruise speed of about eight knots. Bar boats also had a notoriously bad reputation for their seakeeping. “Will roll in flat calm!” was the sort of comment our ex-RN colleagues made about her type. The boat eventually reached Zueitina after a four-week trip and the delivery crew promptly disappeared after being paid off, before even giving Garth a hand-over. He found out why when he went on board. The ship’s inventory looked great, there was everything listed on it that we had asked for. Our boss had kept his word and, although she was an old gal and would be expensive to operate, she had everything we needed to support our dive crew living on board. But what GD found made him immediately refuse to accept the vessel as a dive boat and a couple of days later he walked off the job and quit.

Whilst his leaving left me in charge as supervisor, it was another two months before our crew was able to move on board and whilst we did work and dive the boat during that time, we had to beg borrow and sometimes steal the tools and rigging we needed to be able to function. What had happened was that our boss, having grossly overspent his budget outfitting the boat and being naive about business and ship management, had gone for the cheapest option he could find to deliver the vessel to Libya. The delivery crew had systematically stripped the boat of everything moveable and sold bits at each port they overnighted in. What we got was a hull with a working steam engine but nothing else. There were no fridges, freezers or any dry foodstuffs at all, no mattresses or bedding, no tools or rigging gear. The 16-foot Zodiac RHIB and two off 250hp outboard engines, LP and HP compressors, two off 200-foot air dive umbilicals and a whole inventory of personal dive kit (dry bags, wet suits, bandmasks, fins, knives, etc.) were history.

By this time my crew was two Brits and the rest Maltese (six divers, two deckies and two cooks). They were all good lads and we did some sterling work in what were awful working conditions. One odd thing I learned at that time and have never forgotten is the only foreign language sentence I have ever been able to remember, taught to me by our cook who couldn’t speak any English. It is something like ‘fteet soccur fer te en nil halib gracie’ and means ‘no sugar in my tea and just a little drop of milk, thank you’.

We held out living in the camp and working the boat daily as long as we could, but eventually, around the end of June, we were given notice by Oxy that we had to move onto and live on board the MV Francis A Holmes. I quit the job on my next crew change because I wasn’t prepared to live in the conditions onboard. Whilst I had a single cabin, it was a 10-foot container just aft of the funnel. It had no insulation and we regularly saw 40-degree temperatures during the daytime! But the dive crew had even worse accommodation. All 12 were expected to live in one cabin directly above the engine room.

I found another diving job as soon as I wanted to go back to work, after a couple of weeks off, and started a year or so living in Malta and commuting to work in the North Sea.


However, I was later sent the following report from one of my ex-crew members. It had been published in the Maltese press but the news never reached the UK.
“On the 4th of August 1975 at around 10.30am while transporting some divers to a buoy, an explosion occurred onboard the MV Sir Frances Holmes and shook the ship’s deck. Some pipes were being changed on the deck when this happened. The ship was about three miles out of Zuetina, an oil exporting port in Libya. Four Maltese divers along with two other British died instantly. The Maltese divers were Michael Bonnet, Michael Vella, John Bondin and Carmel Sammut. The British were John McClellan and Barry Caire. The divers worked with East Anglia Electric Diving Limited and Mid Mar. The bodies were brought to Malta for burial. The ship was eventually brought back to service but on the 16th of January 1976 it broke its moorings, drifted ashore and was subsequently broken up.”

Whilst I thoroughly enjoyed the 18 months or so we lived a lovely lifestyle on Malta and have some great memories of family visiting, water skiing in St Pauls Bay, teaching my son to snorkel, my overriding memories are of the MV Frances A Holmes and one other tragic diving related event.

In the first few months on the Zuetina job I became friends with another British diver who had married a Maltese girl and they had opened a small shop selling sea shells, crafts and glassware from the island. Our families often got together for outings to the beach and long evenings in local restaurants. One day my pal went scuba diving in a corner of Valletta (the Maltese capital) harbour, where he knew the sailing boats used to anchor in days gone by and so there were always old bottles and things to be found on the seabed. This day his missus went with him and sat in a deckchair knitting whilst he dived. When he hadn’t surfaced in the time she thought he should have, she raised the alarm and the emergency services started to look for him. He was found quite quickly by a police diver, on the seabed in a kneeling position. The post mortem found he had died when his neck “cricked” and severed his spinal cord. They said it could have happened anytime. That was the last of my pal’s nine lives gone.

Another tale in the next issue.


Brian G. Redden





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