The Glaucus Project and It's Economic Possibilities

Summary

Two divers have been maintained, in good health for a period, of seven days at 35 feet. A simple semi-closed, circuit air purification system was used, and food and supplies brought down by divers. Continuous communication with the surface was available. An oxygen re-breathing technique was used for decompression. The advantages and limitations of the techniques used are discussed with reference to possible future industrial work, in conjunction with submersible and deck decompression chambers, as well as auxiliary equipment, including a closed-circuit oxy-inert apparatus.

Introduction:

By the end of 1964 the French and Americans had completed long-term living experiments beneath the sea with financial assistance from Government, industrial or naval sources. This Project, planned by the Bournemouth Branch of the British Sub-Aqua Club had no such assistance, the cost, about £1000, was met by the club, and its members.

The theoretical data for the experiment was compiled from previous work done in this country, notably by the Royal Navy. In the early part of 1965 we were given the facilities of the library of the Royal Navy Physiological Laboratories, thanks to the close co-operation of Surgeon Lieutenant Commander Elliott.

However, the project was first and foremost an adventure.

Design:

With regard to the design of the house, the following properties had to be borne in mind:
1) It should be large enough to accommodate the two men without producing boredom, cramp or constipation;

2) It should be small enough to be manoeuvrable by average cranes, boats and lorries;

3) Its buoyancy should not be beyond twenty tons, so that the net weight with ballast would not exceed the lifting capacity of the dock crane at Plymouth;

4) It should have a non-contamination W.C., which should have an entrance through the bottom to allow free access by divers;

5) The house should be clear of ballast tray to allow for the divers manoeuvrability such that when on dry land the supports would take the downward weight of the house, and when in the water the supports would take the upward strain of the buoyancy;

6) The buoyancy of the house should be adjustable to allow installation;

7) The interior should have maximum floor space to allow divers to change as well as:

a) Two bunks six feet long with four inch dunlopillo mattresses;
b) Tables for eating, writing and general use;
c) Portholes to provide entertainment;
d) Storage space for soda-lime and gas cylinders;
e) Lighting;
f) Telephone and communications;
g) Soda-lime absorbing trays;
h) WC;
i) Flooring.

Diagram:

From the diagram we can see how these factors of design have been incorporated in the underwater house.

The basic shape of the house was a flat-ended cylinder, this shape giving strength and being easily constructed. It was 7 ft in diameter and 12 ft. long. It was considered that this would allow enough room for comfort, without making towing difficult or necessitating too much ballast.

One corner of the house was separated off by a pair of bulkheads to provide a separate lavatory the air in which could be drained out by means of a pair of turncocks coupled by a polythene hose, after which fresh air could be flown in from the main chamber. This prevented fouling the air in the main chamber, and made it possible to use the lavatory as a ballast tank. Entry into both sections of the house was by a pair of open hatchways in the floor at the lavatory end of the house, the water being kept out by air pressure as in a diving bell.

As a safety precaution a porthole was placed in one of the bulkheads separating the lavatory from the main chamber to allow observation of a crew member in the lavatory, and was also used for checking: the amount of air in the lavatory. Two more portholes were placed in the wall at the other end of the house to allow observation of the surroundings.

There where two bunks, one fixed across the end of the cylinder, leaving about 4 ft 6 ins. x 6 ft. 6 ins of free floor space, while the other folded against one side wall. Along the opposite wall were shelves and a large table, which folded up against them when not in use.

0xygen and air cylinders were stored under the shelves, and the top shelf held a telephone for communication with the surface crew. The telephone and power cables (for lighting) entered the house through a steel pipe welded into the bottom of the house under the end bunk. A closed-circuit television camera, provided by Marconi, was mounted over the\entry hatch, and was connected with the surface by a multi-core cable entering the house through the hatchway.

A petrol generator supplied power and an emergency battery supply controlled and maintained at the surface. A ballast tray was attached to the house by six steel legs. The ballast, pig iron and sections of railway line, weighing roughly 13 tons, was adjusted to the correct weight with short, sections of railway line and railway sleeper chairs, which weighed about 1/2 cwt each and were, therefore, light enough to be handled fairly easily by divers. At each end of the house there was a lug for lifting and lowering.

As it was intended that Glaucus should remain as independent of the surface as possible the atmosphere was controlled by a closed-circuit technique. Though slightly more complicated than the open-circuit method, the closed-circuit technique has several advantages, namely:

• The house crew can alter oxygen levels at will;
  
• Ventilation can be increased or decreased as required;
  
• The continual noise of exhaust bubbles is largely avoided;
  
• This system is more economical and independent of the surface.

Potential hazards are, however, greater than with open circuit systems, since the atmosphere must be monitored continuously, and toxic substances may build up to a level which would not be reached using an open-circuit system.

Our system consisted of four soda-lime trays, containing 'Carbosorb'. The trays were situated near the roof to take advantage of convection currents of warm, expired air, but no circulation pumps were used. Oxygen was introduced through a pair of bleed valves connected to 3,000 l- (110 cu. ft.) British Oxygen steel cylinders. Air cylinders were also carried for adjusting the volume of the atmosphere, flushing the house out, or adding nitrogen to the atmosphere, the oxygen being consumed by the crew.

Carbon dioxide and oxygen levels were monitored by Lloyds (1958) modification of Haldane's apparatus. Visiting divers were instructed to note any odours in the atmosphere on entering, as the occupants soon became adapted to any foreign smells, and activated charcoal was mixed with the soda-lime in one of the trays to absorb impurities other than carbon dioxide.

Dry Run

The purpose of the dry run was to test the efficiency of the artificial atmosphere control, particularly the CO2 absorbers, the oxygen bleeds and the Lloyd gas analysis apparatus.

We also wished to test the interior design; an item which one continually hits one's head on might possibly become intensely annoying during the course of the week.

Further, any psychological disturbances such as claustrophobia might manifest themselves during this two-day period. As the atmosphere could support us for at least twelve hours without undue discomfort we should stay in for twenty-four hours to test the artificial system. In cautiousness this figure was doubled to forty-eight hours. With all installations fitted out as for the dive in September, the subjects were sealed off with containers of water over the relevant entrances.

All went well except on the second day one subject (C.I.) went off his food and only wished for cool refreshing items. During the course of the day J.H. found it progressively more difficult to breathe, whilst C.I. had the same complaint to a lesser degree. In the latter part of the day C.I. found great difficulty in breathing and C.I. vomited twice, and the experiment was terminated.

As many people as possible were encouraged to smell the atmosphere to help find the cause of the trouble, and the two personnel had a medical check up, and were found to have bronchial murmurs. Upon reflection, the considered possibilities for the trouble were soda-lime dust, arsine, paint fumes, formaldehyde bonded resin in the plywood, mercury or stagnant water.The soda-lime was dealt with by insisting upon the wearing of smog masks when the soda-lime was changed, and care was to be taken in the handling of this medium to prevent the formation of dust.

Considering the amount of rust inside the house and the symptoms, it was concluded that arsine was not the cause. To eliminate paint fumes a representative of International Paints was consulted, and on his advice another coat of paint was applied and baked on using a Tropic Heat Generator. All plywood was removed and replaced with Dexion, although it was considered in view of the symptoms that this was not the cause.

All mercury spilt from the gas analysis apparatus was promptly rendered harmless with sulphur during the course of the experiment, and considering the quantity and symptoms this again was considered not to be the cause of the trouble.

Although it was thought that polluted water did not produce the bronchial murmur in the two subjects, it was considered possible that it produced the vomiting in C.I., as the water for sealing the entrances was acquired from a backwater of Poole Harbour.With those precautions taken and in view of the fact that the house during the course of the experiment (unlike the dry run) would have a semi closed system, and finished soda-lime would be discharged direct to the sea, which would not become stagnant, it was thought that the experiment would be successful without the necessity of a further dry run.

Apart from this failing, all other systems functioned correctly, including the artificial atmosphere control, the design, the lighting and communications.

Site

With regards to sites for underwater living experiments, other workers in this field of study have conducted their experiments in the clear waters of the Bahamas, Mediterranean and Red Sea.

However, our experiment was designed to illustrate the industrial advantages of the technique and, as at present much work is being done in the turbid waters of the North Sea, it was useful to find out if this system functioned in poor conditions. It was thus decided to conduct the experiment in British waters at a site which provided a certain amount of shelter, 38 ft. of water thus allowing, for the length of the legs of the house, a static installation close at hand for the ground crew and proximity of a naval hospital and decompression chamber; such a site was the breakwater at Plymouth.

With the close co-operation of C. in C. Plymouth, we were able to secure the use of the fortress at the breakwater for our experiment.

Installation

To install Glaucus, she was ballasted to be about 1 ton positive and was then towed out to the site. Air was blown off by divers inside and she sank under control of the ship's capstan. During the descent water flooded into the chamber, whose volume was compensated for by bottles of compressed air opened by the divers inside.

When firmly on the bottom 2 tons of light ballast (about 1 cwt pieces) were put on the ballast tray and the excess water was blown out of the house, all electrical systems were then connected up.

Diet

With reference to the Diet, several peculiarities of the environment must be considered. First, because of the cold, much energy was used purely in keeping warm.

In addition, any contamination of the atmosphere had to be avoided. It was also considered that the lack of U.V. radiation might cause a shortage Vitamin D that would have to be supplied purely from the diet, and in addition, the high CO2 pressure might affect Calcium and Phosphorous metabolism, which is affected by Vitamin D.

It has been estimated that the average man eliminates about 300 millilitres of flatus per day. Although, even in the enclosed space, this would not be too unpleasant, as the sense of smell adapts rapidly, it could be dangerous as many of the gases eliminated are poisonous.

This demands adequate air purification, and measures to discourage production of flatus.Fried food has been reported to liberate considerable quantities of acrolein. Although this was not considered important for the depth and duration of the experiment fried food is not particularly digestible, and so was avoided.Thus all food was fairly plain and easily digestible, to discourage intestinal fermentation. For the same reason, legumes, which contain large quantities of tryptophan, were omitted from the diet.

A high calorie intake was maintained by the ample provision of carbohydrate. A level of about 3000 Kcals/day being aimed at. The menus were prepared by Mr. J. Bavin an experienced hotelier, and the food was cooked by the current ground crew, who delivered it in watertight food containers. As indicated elsewhere, activated charcoal was used to absorb atmospheric contaminants.

Submersion

During the course of the week under water the subjects had three hot meals a day and additional hot drinks when diving.

They analysed the atmosphere every eight hours, and adjusted it at least every six. During periods of relaxation they listened to the radio, read, or observed the marine life outside the house through the entrance. Unfortunately, during the first half of the week the area was subjected to a West by Southwest wind of force eleven that produced excessively rough seas above the house; unfortunately, the site is not sheltered under such conditions.

However, the house sat firmly upon the sea bed, and the only ill effect (apart from the harsh conditions the ground crew experienced) was a six inch swell in the entrance, which tended to force the subjects eardrums in and cut with successive waves, as has been experienced by submarine personnel when using the submarines snorkel.

Although in itself the storm was no great hardship, it did mean that the visibility took a long time to recover, so that the biological experiments could not be carried out to a conclusion.

At all times a constant eye was kept on the subjects over the closed circuit television, and it was the duty of the current ground crew to cook and take down the meals, together with any other items such as cameras, reagents, newspapers, and dry towels.

Should at any time and for any reason, a decision to terminate the experiment be made, the final decision rested with the ground crew and not with those below as the latter, under such conditions, might not be in a position to make a decision.All events during the course of the experiment were recorded in the log, and telephone communications were made before any action.

When diving, the subjects dived with members of the surface cover using buddy lines and floating coraline cords attached, to the house, carried, an excess of air for the anticipated, dive, and wore apparatus with quick releases which wore known to be reliable, i.e., which would, not release unawares.

In addition, precautions were taken to ensure that the subjects did not to swim more than ten feet above the house; they naturally did not carry snorkels.The W.C. functioned as intended, though as one got excessively cold under such conditions the subjects tended to restrain themselves. This reaction was anticipated to some extent, and it was considered that constipation for 2 days would not do any harm.

As the rise and fall of the tide was about ten feet, the incoming tide had to be blown off with compressed air, and the house, through holes in the W.C. skirting and from there through slightly higher holes to the exterior. This process helped to cleanse the air in the W.C. For the purpose of tidal control, additional compressed air bottles had to be brought down during the course of the week.

With regard to the atmosphere control system we found that CO2 absorption during the dive was barely sufficient. Although levels dropped slowly when both divers were asleep exercise, cold or other divers entering the chamber rapidly raised the levels, on one occasion to 2.2% corresponding to about 36 mm Hg.

The levels were normally kept around 1·5% i.e. between 20 and 30 mm Hg. It was anticipated that high levels might be reached, and a watch was kept on possible subjective symptoms. One observation of interest was made. It was noticed that after a few days breathing appeared to become easier. This agrees with the observations of Schaefer (1963) on submarine personnel subjected to high CO2 pressures.

On returning from a 13 minute dive, however, breathing seemed much more difficult. This dyspnoea appeared to be present for several hours after the dive. However, as already noted, CO2 levels tended to increase after dives, and it is, therefore, impossible without evidence from quantitative ventilation measurements to comment further on this.

The oxygen consumption cannot be discussed without reference to tidal pressure changes. As the tidal range resulted in a pressure change of about 10% it is clear that in order to prevent flooding at high tide, large amounts of gas were needed, this gas being subsequently lost at the next low tide. Gas loss was minimised by allowing the bilges to flood at high tide, but, nevertheless, an estimated 80 cu.ft. was lost at each tide.

As the gas leaving the cylinder contained approximately l6 % of oxygen, and that entering contained 21%, to a large extent our oxygen requirements were met during the tidal adjustments. On occasion oxygen was used to blow back the tide, rather than being bled in continuously.On the dry run the great difference between night and daytime oxygen consumption was not appreciated, and because of this the oxygen level dropped to 17.9 % on one occasion.

During the actual run, however, the regulation of oxygen levels proved delightfully simple, and needed very little attention.About 19 Kg of activated charcoal was used over the entire week. Visitors occasionally noted a slight "painty" smell, or other less well-defined odours, but both subjects remained in good health throughout the experiment. Cousteau (1964) has noted that skin infections can occur in man living under-water, and we also noted this.

However, this may have been due to the lack of hot water for washing rather than to the absence of ultra-violet light.During the last stages of the hyper-oxygenation procedure at the end of the week, at an approximate O2 pressure of 70% ats. both subjects felt slight discomfort on deep breathing, possibly caused by the high oxygen pressure.

As it was considered possible that any congestion of the lungs produced in this way would cause type 2 bends, as described by Walder (1963), both subjects breathed deeply and held their breath a few times, before ascent, in order to open up any atelactic areas in the lungs, as described by Buxton (1957).

No symptoms of any type of decompression sickness wore noted.Two factors in the environment were quite noticeable. First, the fact that the temperature never rose above 16.2° C., and. remained at about 15.4° C at floor level, and second, the fact that the air was saturated with water vapour.

Whether damp air is as harmful as is popularly supposed is open to question, but certainly a temperature of 16° in an environment where extensive exercise is not only undesirable (because of CO2 production), but also limited by space, is most unpleasant.

Decompression & Ascent

By the end of the week it could be considered that all tissues were saturated to that depth though most tissues would be saturated after 6 to 8 hours. Thus, it was important that the personnel should not surface when outside the house, as this could produce a bend, the personnel being at a depth of 35 ft. for mean tide level (30 ft. low tide, 40 ft. high tide), which was an equivalent depth of 38 ft. for 15% 02 and 83.5% inerts.

In cautiousness the personnel did not pass more than ten feet above GLAUCUS so that they wore always more than 8 ft. deep, the possibility of bends would be very small.

At the end of the week the O2 level was raised such that the equivalent air depth was 23 ft. It was considered safe to surface from this equivalent depth though C.I. breathed an 80% O2/20% N2 mixture for an equivalent of 3.5 hours, i.e. ¼ hr. on, ¼ hr. off, ½ hr. on, ½ hr off, 1 hr. on, as described by Cousteau (1963) for an ascent from 35 ft. J.H., instead of breathing this mixture, planned to remain at a depth of 6 ft. for 3 hrs, though this was not possible as during the ascent the underwater house came up too fast and rose out of the water by 3 ft'- This made her about 3 tone negative which took her to the bottom again where she was half full of water.

Another attempt was made but also failed. The personnel then made an ascent, using aqualungs, after which they were taken to the naval hospital at H.M.S. Drake, where they were kept under observation for 2 days.

No symptom of bends or any other ailments were observed. Later the house was recovered by using the same process except for tying boards over the entrance, which acted as a mushroom valve letting air out but not water in.

Although the hyper-oxygenation procedure before ascent probably accounted for the absence of any symptoms of decompression sickness, it should be borne in mind that the procedures used were, because of the lack of facilities, somewhat arbitrary, and should therefore not be regarded as safe routines for subsequent similar dives.

Further tables produced from extensive experiments in the laboratory would have to be used in any deeper experiments.

Psychology

Cousteau, during the Diogene experiment, and the American Navy, in their Sealab 1 experiments, remarked on changes in the psychological condition of their subjects. Cousteau observed, quite severe abnormalities, including intense depression, nightmares and a recalcitrant attitude towards the surface personnel.

He also described a rather vague feeling of "one-ness with the sea", which his divers experienced.

The American Navy noted less severe symptoms, but still noted a dislike for orders from the surface, which gradually developed over the experiment.We are inclined to consider that these reports have, perhaps, been coloured by the fact that both these investigations have included psychologists anxious to observe any changes.

Although the subjects experienced some differences of opinion with the surface personnel, these differences were perhaps less than those experienced between some of the surface crew themselves, and certainly no more than would have been expected 'under the somewhat arduous conditions.

The subjects were also more pre-occupied with the immediate discomforts of cold and damp than with any mental reactions. We did, admittedly, get some exhilaration, as from any novel experience.

In addition to this reason for the lack of any noticeable psychological reaction there may be two more.

Both subjects had been diving together for five years, and both were determined to stay down for the full week, other factors being favourable. However, it cannot be assumed from this result that future experiments of longer duration and harder work, will not produce mental disturbances, although we do not consider this a major problem to be overcome.

Results

As in the present experiment power was supplied by a surface generator which was maintained by the surface crew; there will have to be a surface engineer to maintain a constant power supply (at all times) in any future work or the power will have to be contained within the house (fuel cells may prove an interesting development here). As the house was found to be extremely unstable, vertically, it is recommended that its volume of air be kept constant during ascent and descent. Further, as carrying ballast is tedious, ballast tanks would save considerable labour and time. If the house is to be lowed, then it would be advisable to make it of a streamlined shape, as most of it will be submerged during lowing.

The interior design of the present house was adequate, though the water locked W.C. proved inconvenient, and it would be advisable to redesign this item. The furnishings should be of a rugged nature, and the house should be divided into wet and dry portions thus making for greater comfort and efficiency.

It is not possible to produce a recommended design at this stage as this will depend on the specific requirements of the house, e.g. operating depth, decompression system, number of personnel, transporting methods, duration, and type of work to be carried out are all factors affecting the design.

Owing to the extreme cold it is recommended that a more efficient diving suit be developed, as well as insulation and heating for the house.

If personnel intend to work beyond visible limits of the house, it is necessary that communication between diver and house is positive, though roping methods were found to interfere with work, and it is therefore suggested that ultrasonic communication be used. This would also increase the divers efficiency of work owing to diver communication.

If houses are to be used deeper down, then mixtures will be required. If these contain Helium then house/diver recirculation should be developed to save the expense of wasted Helium. Owing to the viscosity of water and the buoyancy of the diver, the diver's movements are hampered, and for this reason power tools should be developed, with appropriate pneumatic or hydraulic power supplies.

With regard to the atmosphere control, the main defect in the system was undoubted CO2 absorption. Although considerable circulation was supplied by convection (as was shown by the fact that if a soda-lime tray was placed at ground level little reaction took place), this was insufficient. In any future experiment a circulation system is essential. This, of course, involves the use of a pump, and this is a problem. If an electric motor is used to drive it, care must be taken to avoid contamination of the atmosphere by ozone. Oil fumes must also be avoided - Tufnol bearings might be useful here. Ideally the airflow should be at least 100 l/min./person. A counter-flow system, arranging the older soda-lime absorbers at the inlet end of the system, would conserve soda-lime, which appears to absorb more sluggishly after a time. A possible arrangement would be incorporating air-drying (by refrigeration and condensation) and heating.

It was found more convenient to release oxygen straight from the cylinder than to use the bleed valves. However, such a system would be unsatisfactory for a semi-automatic set-up, where a bleed would be essential. A "basic" bleed, supplemented by additional taps for adjustment and periods of high oxygen consumption might be the best system.

A continuous monitoring system would be desirable. This could be supplied by the circulating pump and consist of automatic analysers, possibly recording on a chart, and calibrated at intervals by known mixtures.

Insulation, heating and drying would, add greatly to the comfort and efficiency of the divers. Refrigeration drying would be the best, as drying agents such as silica gel could not cope with the enormous amounts of water involved.

Safety precautions will be necessary if a mechanised system is used. To guard against pump failure, soda-lime respirators should be available for periodic checking of the automatic system and. for emergencies.

Economic Potential

In considering the future of the system we must first consider the needs. The main work that has to be carried out by industrial divers at present is construction and. assembly; apart from this there is some amount of salvage, maintenance and survey. For all this work surface support is necessary to provide materials and ancillary float plant, such as machinery, grab cranes and airlifts.

If divers are to work under these conditions there is no need for them to go to the great expense of placing themselves, self contained, on the seabed. For small tasks Submersible Decompression Chambers (SDCs) and. Dry Decompression Chambers (DDCs) are now being used. For slightly larger tasks larger units are used as in the Cachalot example.

As the need for diving time increases small "workman's huts" may be put down on the jobs - similar in principle to GLAUCUS - to be used as a refuge. These units would mean the diver would, probably go below for his working day and could, take refreshment, spare breathing mixture and a selection of tools from his submerged unit. The reason why these extra items would not be carried in the SDC is that being a pressure chamber and as it must be manoeuvrable it must be small.

As the need for diving time increases further larger surface chambers will have to be built to accommodate the men and equipment, as the price of such units is very high. It will eventually become cheaper for the divers to be placed in a vessel on the seabed, even taking into consideration the cost of partial isolation that will require an umbilical system of hoses and cables. However, at this stage food, dry towels and other items will be brought down in the SDC. Taking this logic further the submerged unit will become independent of the surface as regards manpower and cooks etc. will be housed below.

Thus we may conclude that to depths at which man cannot only work for short periods but can also live the most economical system for the immediate future would be one using a suitable combination of various sized SDCs, DDCs and submerged units, depending on firstly the size of the task in hand and secondly the area to be covered. For depths below which man cannot live continuously but can work for short periods SDCs and DDCs will be used.

Other workers in this field have, up to the present time, only taken "shots in the dark" when looking for an answer to the problems of deep diving. There is no single answer to be found. The answer is to be found in a flexible system that is made up of units of overlapping capabilities.

As well as submerged units from which divers can work they must also have the tools and clothes for the job, heated suits, ultrasonic communications, pneumatic tools, bearing in mind that this should be heavy gear for steady work and light gear for survey and observation. Most of this equipment has been designed already, though it needs a great deal of development.

An item which I have not mentioned yet is the breathing apparatus to be used by the diver, many types are now being developed, semi-closed circuit apparatus, SDC or House to Diver recirculation and, of course, open circuit. However, many attempts have been made to devise a completely closed circuit oxy-helium unit using an oxygen sensor to keep the partial pressure of oxygen constant at all depths. Using differing techniques to this in which the oxygen partial pressure is kept within tolerable limits rather than constant, and by utilising a mechanical valve system only, we have designed an apparatus that overcomes the problems presented by the unreliable nature of oxygen sensors and bleed valves when used with helium.

If we develop the industrial diving system and the closed circuit apparatus as described we will develop a system, which will be at least competitive to other systems being developed for the needs of contractors. However, the main amount of development being done in this field of work is at present being done in America. I do not refer in this case to the much-publicised Government and Naval projects but to the industrial developments. The Americans are clearly in the lead. They have sunk many millions of dollars into research-and have developed some highly sophisticated techniques' British industry has also done some development, notably with pressure chambers and SDCs: the large oil companies have also undertaken some research.

I think that much of this work falls into one of two categories. Firstly, unnecessary inefficiency due to a lack of imagination, money or effort. Secondly, unduly costly due to, ironically, too much money and imagination coupled with a lack of straightforward diving practical knowledge.

I think the system I have briefly outlined in this talk provides a solution that falls into neither of 'these categories but gives a realistic answer to an ever growing problem.