Safe diving practices varies from Training Agency to Training Agency. Here are the practices for PADI and BSAC.
Also, the BSAC Divers Code of Conduct.






This is a statement in which you are informed of the established safe diving practices for skin and scuba diving. These practices have been compiled for your review and acknowledgement and are intended to increase your comfort and safety in diving. Your signature on this statement is required as proof that you are aware of these safe diving practices. Read and discuss the statement prior to signing it. If you are a minor, this form must also be signed by a parent or guardian.

I, __________________________________________________, understand that as a diver I should: (Print Name)

1. Maintain good mental and physical fitness for diving. Avoid being under the influence of alcohol or dangerous drugs when diving. Keep proficient in diving skills, striving to increase them through continuing education and reviewing them in controlled conditions after a period of diving inactivity.

2. Be familiar with my dive sites. If not, obtain a formal diving orientation from a knowledgeable, local source. If diving conditions are worse than those in which I am experienced, postpone diving or select an alternate site with better conditions. Engage only in diving activities consistent with my training and experience. Do not engage in cave diving unless specifically trained to do so.

3. Use complete, well-maintained, reliable equipment with which I am familiar; and inspect it for correct fit and function prior to each dive. Deny use of my equipment to uncertified divers. Always have a buoyancy control device and submersible pressure gauge when scuba diving. Recognize the desirability of an alternate air source and a low-pressure buoyancy control inflation system.

4. Listen carefully to dive briefings and directions and respect the advice of those supervising my diving activities.

5. Adhere to the buddy system throughout every dive. Plan dives including communications, procedures for reuniting in case of separation, and emergency procedures with my buddy.

6. Be proficient in dive-table usage. Make all dives no-decompression dives and allow a margin of safety. Have a means to monitor depth and time under water. Limit maximum depth to my level of training and experience. Ascend at a rate of not more than 60 feet/18 metres per minute (30 feet/9 metres per minute is recommended).

7. Maintain proper buoyancy. Adjust weighting at the surface for neutral buoyancy with no air in my buoyancy control device. Maintain neutral buoyancy while under water. Be buoyant for surface swimming and resting. Have weights clear for easy removal, and establish buoyancy when in distress while diving.

8. Breathe properly for diving. Never breath hold or skip breathe when breathing compressed air, and avoid excessive hyperventilation when breath-hold diving. Avoid overexertion while in and under water and dive within my limitations.

9. Use a boat, float, or other surface support station whenever feasible.

10. Know and obey local diving laws and regulations, including fish-and-game and dive-flag laws.


Signed                                                                                          Date                                      








 This is an alphabetical guide to the safe practices of sports diving as recommended by the British Sub-Aqua Club (BSAC) the Governing Body of the sport of sub-aqua diving in the UK. The ideas expressed within reflect the current thinking of the National Diving Committee and the advice on which it is acting.

Diving is an adventure sport and like all adventure sports its participants require differing levels of enjoyment and challenge. At one extreme we have the equivalent of the Himalayan mountaineer who, in peak condition accepts the challenge of new routes and exploration. At the other extreme we have the equivalent of the weekend summer climber who potters around on popular well-climbed rock faces.

What is safe diving practice for the former may well be very perilous for the latter and so the contents of this booklet are not a set of rigid rules but recommendations for safe diving practices. These recommendations can be amended depending upon the particular type of diving being planned and the experience and capabilities of the two divers carrying out the dive.

Where appropriate the advice in this booklet is also applicable to snorkel diving.

The Diver's Code of Conduct is appended to the end of this booklet. It contains sensible advice on the conduct of all dives, and is seen as complementary to the guidance given here.

 Safety and Incidents Advisor

BSAC National Diving Committee


Ensure that your access to the water is safe and that you can successfully regain contact with your boat/beach/shore. Always ensure, when diving from the land, that it is possible to climb out at the planned exit point at varying states of the tide.


Any member involved in a diving accident or incident should notify BSAC HQ. An incident report form will then be sent, which should be completed and returned as soon as possible. Reports are treated as strictly confidential and are used to prepare an analysis of safety performance each year. If there is any possibility of an third party insurance claim arising out of the circumstances it is particularly important that a form is completed without delay.

 Air Reserve

Always ensure you have an adequate reserve of air (at least 25% is strongly recommended) at the termination of a dive. The amount of air deemed to be an adequate "reserve" will obviously depend on a number of factors including the size and working pressure of your main cylinder together with the depth and type of the dive a standard figure is not appropriate. The reserve should be sufficient for a normal ascent, plus any decompression stops, and to allow adequate amounts for surface swimming. Remember that rates of air consumption can vary enormously with the effects of cold, fitness, experience and depth and you should monitor your own and your buddy"s air supply regularly.

 Alternative Air Source (AAS)

The BSAC strongly recommends that all divers carry an alternative air source (AAS) in the event that they may need to share air underwater.

Suitable AAS include an "Octopus Rig" (a second 2nd stage fitted to the same 1st stage of the regulator, which includes the type fitted to a direct feed). In this case divers should be aware that a first stage failure on their regulator will affect both second stages and render them in-operative.

A more strongly recommended alternative, however, is a totally independent air supply such as a "Pony cylinder" (a small 2-3 litre auxiliary cylinder attached to the main cylinder with its own regulator assembly) or separate regulators attached to each cylinder of a matched pair. If a manifold is fitted to the pair of cylinders, making them into a "twin-set", it should allow the diver the ability to isolate each cylinder/regulator assembly should a failure occur. Auxiliary cylinders having a capacity of less than 3 litres and ABLJ/BC mouthpieces are not considered adequate AAS.


Diving at altitude, or travelling to altitude (including flying), either before or after diving, involves the diver being exposed to a reduced atmospheric pressure. This can both affect the decompression procedures required and increase the diver"s susceptibility to decompression illness. The BSAC 88 Decompression Tables, Levels 1-4, have been specifically designed to allow the various factors involved to be taken into account in a simple manner. They should be used for all dives at altitude and also for determining whether a particular dive/journey sequence involving an excursion to altitude is permissible. (See BSAC 88 Decompression Tables)

 Ascent Rate

Maintaining a safe rate of ascent is vitally important in preventing possible decompression illness and the risk of gas embolism. The BSAC 88 Decompression Tables have been calculated on a maximum ascent rate of 15 metres per minute up to 6 metres depth and 6 metres per minute from 6 metres to the surface and this must be adhered to when using the tables. Some dive computers incorporate slower ascent rates of 10 metres per minute but all divers are recommended to follow the practice of ascending at 6 metres per minute from 6 metres to the surface.

Repeated multiple ascents should be avoided as they may result in decompression illness. Particular care should be taken when carrying out the various ascent training drills, for which specific advice is available.

"Sawtooth" dive profiles which involve repeatedly ascending and re-descending over an uneven bottom should be avoided, but the practice of returning to the surface from maximum depth in stages is encouraged.

 Assisted Ascents

The National Diving Committee strongly recommends the use of an alternative air source (see Alternative Air Source) as the prime method of assisted assent, and that all divers should carry such equipment. The less preferable alternative of sharing from one demand valve remains a useful training drill since it may be necessary to share with someone who has only the one.

 Authorised Branch Dives

An authorised dive by a BSAC Branch is one carried out with the prior knowledge and approval of the Branch Diving Officer. A properly qualified and appointed dive marshall shall be present and shall be in charge of all diving activities for the duration of the dive/expedition. All Branch dives should be carried out in accordance with current BSAC rules and recommendations for safe diving.

AV (Artificial Ventilation) and CC (Cardiac Compression)

When demonstrating or practicing AV in the water, a proper seal (usually nose) should be made. A simulated seal is not sufficient to give the sense of realism required, and does not guarantee a successful acquisition of technique. The use of a manikin is strongly recommended when practicing AV on land.

Cardiac Compressions (CC) should never be practiced on a conscious breathing subject, a manikin should always be used.

The following rates for AV & CC are recommended:-

         AV On land or static in deep water approx. 10 breaths/1 min.

         When towing 2 breaths/15 sec.

         CC 100 compressions/1 min.

         Combined AV and CC Solo rescuer: 2 breaths/15 compressions. Two rescuers: 1 breath every 5 compressions.


Ensure your boats operate at slow speed in any area where divers are below. Those in the boat should keep close watch for divers surfacing unexpectedly.

When dropping divers into the water, or retrieving them, ensure the engine is in neutral, and that they are well clear of the propeller before you engage gear. All boats should be marked for easy identification and should be properly equipped before taking them to sea.

Boats used on BSAC events must have appropriate Third Party insurance cover.

When using boats take note of the recommendations for boat users laid down in the Diver's Code of Conduct.

BSAC 88 Decompression Tables

The NDC considers the BSAC 88 Tables to be the safest sports diving tables available in the world and recommends their use. The BSAC 88 Tables, Levels 1-4, have been specifically designed for sports diving on air and incorporate new thinking on the avoidance of decompression illness.

The Tables promote safer diving practices, particularly by encouraging slow, controlled ascent procedures and allow divers for the first time to make allowance for atmospheric pressure changes due to weather or changes in altitude. Due to the wide variations in human physiology and the large number of factors that can affect your susceptibility to decompression illness, no table can guarantee to protect you against all risk. Whenever diving the following advice should be taken into account:

1.       The maximum recommended depth for recreational diving is 50m. Specific depth restrictions, appropriate to skill level and experience, are applicable to some BSAC diving grades (see Depth). When carrying out two or more dives in one day, perform the deepest dive first.

2.       It is recommended that no more than 3 dives be performed in any 24 hours. Any dive series involving consecutive days diving to 30m+ should be limited to four days, after which a 24 hour break should be taken.

3.       Always be in control of your buoyancy, especially during the ascent, and observe the recommended ascent speeds. (15m / min to 6m and 1 min from 6m to the surface).

4.       It is permissible to conduct slower descents and ascents, whilst remaining within the dive profile envelope, but multiple "saw tooth" ascents and descents should be avoided.

5.       Be aware that smoking, alcohol consumption, tiredness, age, increased body fat and any medical condition affecting the respiratory or circulatory systems may increase your risk of decompression illness. Susceptibility can also be increased with excessive physical exertion during or immediately after a dive.

6.       When diving with Nitrox use the BSAC Nitrox Tables to determine the safe limits for your planned dive. (See Depth and Nitrox)

Buddy Diving

It is important for safe diving that divers are formed into appropriate buddy pairs. Buddy diving means a pair of divers operating as a unit, each taking some responsibility for the safety of the other. On every dive one diver, usually the senior in grade or experience, should be elected as the dive leader. Divers with a minimum grade of Club/Ocean Diver may dive together at the discretion of the Branch Diving Officer. Divers below the grade of Club/Ocean Diver (i.e. divers under training) must be led by an instructor. 

When snorkelling, dive alternately so that the snorkeller underwater is covered by their buddy at the surface.

Buddy Lines

In conditions of poor visibility, you may wish to use a buddy line to retain contact with your buddy. A line two to three metres long is ideal, with a shackle or small karabiner spliced to each end. This allows it to be looped over wrists, if so desired, or it can be clipped to a suitable piece of equipment e.g. BCD, to leave both hands free.

Buoyancy Compensators (BCD)

Divers need to be able to adjust their buoyancy underwater to compensate for buoyancy losses due to pressure changes on descent, and then to jettison this buoyancy as they ascend. This may be provided by inflation of a drysuit or by means of some buoyancy compensating device. Total reliance on a drysuit is not sensible and a suitable buoyancy compensator should be worn on every open water dive.

There are three main types of buoyancy compensator currently on the market, the Adjustable Diving Vest (ADV),the Stabiliser Jacket (STAB) and the "wings" style of BCD.

Most are made in various sizes and care should be taken to choose the correct size and amount of buoyancy offered. All buoyancy compensators must have a direct feed mechanism for routine buoyancy adjustment.

The divers other requirements for a buoyancy system are to stay afloat at the surface or to give emergency buoyancy whilst rescuing or being rescued. An inflated drysuit is not a good solution in these surface situations and drysuited divers must wear a buoyancy compensator to maintain and control buoyancy safely.

Buoyancy Compensator Cylinders

Some Buoyancy Compensators can be fitted with a small air cylinder for emergency inflation. At the present time there is no legal requirement for BC emergency cylinders to be tested. Since the filler of the cylinder is usually the owner, it is his / her responsibility to ensure that the cylinder is in good condition. It is strongly recommended that BC cylinders are visually inspected every year.

Never overcharge a cylinder and avoid storing one for any length of time fully charged. Ensure that the working pressure of the BC cylinder is compatible with the working pressure of the aqualung cylinder. Avoid completely emptying such cylinders since, if the valve is allowed to remain open, any water in the buoyancy jacket may be drawn into the cylinder.

It is strongly recommended that BC cylinders should not be filled with enriched air (Nitrox) mixtures.

Buoyant Ascents

These fall into two categories, buoyant ascents in an emergency, and controlled buoyant ascents in a non-urgent situation. In the former it is vital to remember the risk of embolism and positive breathing out is absolutely essential. In the latter case, the training programme teaches the correct techniques to ensure a safe ascent rate in a controlled manner. It is most important that an ascent rate of 6 metres per minute is achieved from 6 metres to the surface and this requires that the diver is always capable of being neutrally buoyant at 6 metres with a near empty cylinder.


For safety reasons only properly trained and competent people should operate compressors. If you use a portable petrol or diesel engine take care not to have the air intake in a place where fumes may be ingested with the air, and never use the compressor in a site where it is an annoyance to other people. It is essential that air of a high standard of purity is delivered. BSAC Regional Coaches have access to air purity testing kits and should be contacted to carry out such tests.

The production of compressed air for use in oxygen enriched mixtures requires specialised oil-free equipment and training. Only properly trained operators using appropriate equipment should undertake this. (See Nitrox)


Dive computers offer accurate and automatic recording of depth and time and continuously calculate the diver's decompression requirements according to the depth and duration of the dive. Computers are also available with advanced features such as the ability to calculate decompression requirements for a variety of Nitrox mixes, and also to monitor available air and air consumption rates. The use of a dive computer is no substitute for proper dive planning, including proper attention to air requirements and dive time.

It is recommended that divers choose a computer which is at least as conservative as the BSAC 88 Decompression Tables on a rectangular dive profile. Individual susceptibility to decompression illness varies and can be affected by a number of factors, for which no computer or decompression table is able to allow. Divers should be aware of this and avoid pushing computers beyond their limits. The advice on safer diving attached to use of the BSAC 88 Tables applies equally to computer users and should be followed. (See BSAC 88 Decompression Tables)

Cylinders (Air)

Air Cylinders to the obsolete specifications HOS, HOT (steel), and HOAL 1, 2, 3 and 4, (aluminium) are still legal for use by divers, although no longer manufactured. The current specifications approved by the Health and Safety Executive are BS5045 Part 1 (steel) and BS5045 Part 3 (aluminium). Diving cylinders must be tested according to BS5430 Part 1 (steel) and BS5430 Part 3 (aluminium). These specifications call for diving cylinders to be visually inspected every TWO years and subjected to a hydraulic test every FOUR years.

Divers should ensure that test stations carry out their tests in accordance with BS5430 and should obtain a test certificate which states this. Test stations approved by the Inspectorate for Diving Equipment Servicing and Testing (IDEST) are strongly recommended. The cylinder should be stamped by the test station after every inspection / test.

Cylinders (Nitrox)

Cylinders for use with Nitrox should be dedicated to this use, marked with a 100mm green band around the cylinder and clearly labelled to show the gas mixture contained (oxygen percentage) and its Maximum Operating Depth.

Cylinders should be regularly (usually annually) cleaned to oxygen service standard. Oxygen service standard is essential where the oxygen content is 40% or greater and strongly recommended for mixtures where the oxygen content is greater than 21%. Nitrox cylinders should have a maximum working pressure of 232 bar.

Cylinder contents should always be analysed at the time of filling and again immediately before the dive. (See Nitrox and Compressors)


All dives involve some decompression, which normally takes place during the ascent and subsequent period on the surface. It follows that it is as important to correctly perform these stages as it is to monitor the dive itself. Decompression computers can assist in this if they are correctly used and are programmed to an appropriate algorithm. This means for a simple rectangular profile they should give dive times as conservative as the BSAC 88 Decompression Tables.

It is important to realise that both tables and computers are unable to make allowance for factors such as age, fitness, exertion, obesity and injuries, which may all significantly affect susceptibility to decompression illness (DCI). Divers should therefore be aware of these factors and avoid diving beyond their limits. Take particular care when planning repeat dives. Where two or more dives are being made the same day it is good practice to carry out the deepest dive first. It is also good practice to achieve maximum depth as early in the dive as possible and to avoid re-descending once any ascent has commenced.

Decompression illness symptoms vary between those so sudden, that immediate air evacuation to a chamber is vital, to those which may not become apparent for some hours. Some of these less dramatic symptoms, such as tingling and numbness, may well be delayed but can be more serious and produce greater disability than the excruciating pain often associated with DCI in a joint. Tingling and numbness are included in this category.

Severe DCI symptoms, occurring at sea, require rapid transfer of the subject to a recompression chamber, laid flat on their back and if possible, the administration of 100% oxygen and fluids. Being bounced, rapidly, in a small boat is almost certainly going to worsen the symptoms rather than help the situation.

For assistance with decompression illness, advice in the UK can be obtained from the National Decompression Illness Helpline.

When at sea, contact should be made via the Coastguard on VHF  Channel 16. When on shore, contact can be made via the following 24-hour telephone numbers:

         If calling in England, Northern Ireland or Wales call 0831 151 523 to be connected with the relevant department of the Royal Navy

         If calling in Scotland call 01224 681 818 to be connected with the Aberdeen Royal Infirmary.

         For other emergency assistance, when ashore in the UK, use 999  or 112, as usual.

         When diving outside of the UK, ensure that you know the local  emergency contact procedures.

(See BSAC 88 Decompression Tables / Oxygen)

Decompression Stops

The NDC considers the BSAC 88 Decompression Tables to be the safest sports diving tables available in the world and recommends their use. In areas of the world where other tables are being used, members should check the correct application of these tables and if in doubt use the BSAC 88 tables. Dives requiring decompression stops should be well planned beforehand and executed according to recommended techniques. Avoid deciding upon decompression stops once in the water.

An accurate means of measuring depth and time is essential, as is an appropriate means of controlling the depth of the stops, such as a shotline. Any diver who has missed planned decompression stops could be suffering from decompression illness and should be returned to the shore as quickly as possible. No attempt should be made to carry out any form of re-entry decompression as this inevitably worsens the situation. The diver should be treated as a potential casualty, kept quiet and administered oxygen and oral fluids. Emergency advice should be sought and their recommended actions followed - see the section on Decompression for contact information.

(See BSAC 88 Decompression Tables/Decompression/Oxygen)

Delayed SMB

A Delayed SMB is no substitute for a fixed shot-line and wherever practical a shotline should be used for the ascent and descent phases of the dive. However there are situations where the use of a shot line or a conventional SMB may not be appropriate, and in these circumstances consider the use of a Delayed SMB. Ensure that you practice deployment and usage of the Delayed SMB in safe, simulated conditions before using one in earnest, and when deploying the Delayed SMB do not attach the free end of the line or reel to yourself, or to other personal equipment.


A depth of 50 metres is recommended as the limit for normal recreational diving. Within this limit BSAC divers have additional restrictions upon the maximum depth to which they should dive, dependant upon their diving grade. The specific depth limitations for each grade are contained within the current Diver Training Programme and Qualification Record Logbook.

There is statistical evidence that decompression illness is more likely to occur on dives deeper than 50 metres, even though decompression tables may be strictly adhered to, and such occurrences are usually serious, with central nervous system involvement. When diving deeper than 35 metres, special care with planning is vital, and recommended deep diving practices should be adhered to. The NDC strongly recommends that dives in excess of the recommended maximum depth limits should not be undertaken by recreational divers.

When diving with oxygen enriched mixtures it is essential that the maximum operating depth for the mixture is adhered to. Failure to do so may have fatal consequences due to the onset of oxygen toxicity.

Distress at Sea

Distress at sea can range from an extreme form of decompression illness, where life is threatened, to divers being lost on the surface having been swept away by the tide. Procedures to deal with such a range of emergencies are as follows:-

Any dive boat at sea requiring Search or Rescue assistance for a missing or overdue diver should use a "MAYDAY" call if life is in danger. Less serious, but nonetheless urgent requests (e.g. a boat drifting with no engine), may warrant a "PAN PAN" (Urgency) call. Both these calls would be broadcast on VHF Channel 16. If your boat does not carry VHF radio it is sometimes possible to attract the attention of passing vessels who may radio on your behalf.

Flares can be used to attract attention, either from the shore or from other vessels in the area. It is important that flares are not wasted, so only fire them if there is someone likely to see your signal. Several Maritime and Coastguard Agency reports, each year, indicate that some divers leave it too long before raising the alarm. Do not delay too long if you are convinced problems are arising which you cannot control.

For distress at sea, where decompression illness is involved, see Decompression.

Dive Discipline

It is a rule of the BSAC that the Dive Marshal has the authority of the Branch Diving Officer to suspend a member from diving if instructions are not obeyed.

(See Authorised Branch Dives)

Dive Leadership

See Authorised Branch Dives/Buddy Diving, also Dive Planning and Organisation.

Dive Planning and Organisation

When boat dives are taking place, make sure that a responsible person on shore has details of your dive plan and estimated time of return. The Maritime and Coastguard Agency (MCA) is always grateful for a phone / radio call to brief them of your intentions, and confirmation that you have returned to shore safely. Accurate records of diver training, dives and expeditions should be kept at all times.

Diving Flag

The International Code Flag 'A' should always be flown when diving. For small boats it should be at least 1/2 metre square and should have the means to fully extend it in calm conditions. It should not be flown when travelling to or from a dive site.

Diver Propulsion Vehicles

A Diver Propulsion Vehicle (DPV) is a very effective and effortless way for the diver to cover a large underwater area. By riding, or being dragged along by the DPV, the diver is provided with greater mobility and range for the dive, as well as breathing a reduced amount of the appropriate  breathing mixture due to the reduced effort required for motion. Such a reduction in gas consumption may therefore also allow the diver to spend a longer period of time underwater, subject to their personal decompression requirements.

The major risks related to DPVs are listed as follows:

         Difficulty looking at, and therefore properly monitoring, pressure, depth and other gauges whilst holding on to the DPV. However the diver can pause from time to time to review these instruments.     

         Loss of equipment due to the speed of the DPV. The diver will need to ensure that all ancillary equipment such as torches etc. are securely strapped to the person, and, in addition, do not dangle from the body where they could fall into the propeller guard.     

         Barotrauma and other pressure related injuries could occur as a consequence of a rapid descent, and particularly on the ascent. Due to the potential speed that the diver may travel using a DPV,  these vehicles should be very carefully used for the descent and ascent phases of the dive.     

         Diver separation from the buddy could occur, unless the buddy also has a DPV. It is important that both members of the buddy pair use DPVs, since if only one member of the pair has such a vehicle then it is quite possible that the pair may become separated due to their obvious different speeds of movement through the water.

         Collision in poor visibility. Always a potential risk, but unlikely.

Diver Recall Systems

When divers need to be recalled to the surface there are several means available. If they are using SMB's a pre-arranged signal on the line is sufficient. Thunderflashes can be purchased, but ensure they are of large enough size and that they are weighted in order to sink before you need to use them. Endeavour to allow divers to experience a thunderflash going off as a training drill so that they will recognise the sound when they experience it in a real situation.

There is also a diver recall system available using a .38 'blank' cartridge. This allows several signals to be fired. Divers are cautioned against taking such devices abroad, particularly when flying.


If you are taking prescribed medication of any kind, do not dive unless clearance has been given by an approved Medical Adviser.


There are two main types of drysuit in common use, the membrane type (which require adequate undersuit thermal protection) and foam neoprene drysuits. Each type has different weighting requirements. The buoyancy a drysuit provides cannot be guaranteed to support a diver on the surface safely - the air in the suit is too easily vented when swimming or in rescue situations. For this reason, plus the common sense of having a "redundant" method of obtaining controlled buoyancy, a buoyancy compensator (BCD) is worn.

Drysuit training can be undertaken by Branches during initial training or at any time in later training. Sheltered water / pool training is essential before progressing to open water. Do not wear excess weight when using a drysuit, wear just sufficient to be neutrally buoyant at 6 metres with a nearly empty cylinder. Divers have experienced problems on ascents because they have used both buoyancy compensator and drysuit to compensate for buoyancy loss, and have not enough hands to operate all the controls plus coping with whatever else they might be carrying.

Drysuited divers should include their method of achieving neutral buoyancy as part of the buddy check and dive brief. They should also advise their buddy on whether their suit is capable of being used as the main source of buoyancy during a Controlled Buoyant Lift, or whether their BCD will have to be used.

The NDC recommends that drysuited divers adjust their buoyancy underwater by introducing air into their drysuits, rather than into their buoyancy compensators.


It is extremely dangerous to attempt to recover or retain live explosive devices. Immersion in water could render them very unstable, especially if they are consequently dried out, so keep well clear of any such devices you find. If you consider that they are in a dangerous location, inform the Maritime and Coastguard Agency (MCA).


1.       attempt to bring them to the surface and on no account abandon  them in shallow water, or on the beach;

2.       undertake the use of underwater explosives for carrying out underwater work without a recognised course of training;

3.       dive near sites where underwater explosives are being used since the shock waves can be fatal.

Fitness to Dive

Diving uses as much energy as moderate to heavy work. Before resuming diving, after a lay off, you are advised to regain physical fitness, practice basic underwater skills in the pool or sheltered water training area and complete a series of "work up" dives before diving to depth. Ensure all divers are both physically and psychologically fit for the dives they plan to undertake.


Orange smoke and red handheld / rocket flares should be carried by all dive boats in order to attract attention when in difficulties at sea. Similar flares, in waterproof containers, are available for divers to carry in the event of them becoming lost at sea. Flares should not be used for signalling purposes in a non-emergency situation. Gun type flare launchers require a Firearms Certificate for use within the UK.

Divers are cautioned against taking such devices abroad, particularly when flying.

Flying and Diving

Flying or travelling to altitude after diving can give rise to decompression illness. Flying or travelling to altitude before diving may increase the risk of decompression illness on a subsequent dive. It is therefore recommended that divers use the BSAC 88 Decompression Tables (Levels 1-4) to determine whether the proposed dive/journey combination is acceptable.

(See BSAC 88 Decompression Tables/Altitude)


Hyperventilation, before a snorkel dive, should be avoided at all costs, as it has the effect of flushing out carbon dioxide from the respiratory system. Build up of carbon dioxide, rather than lack of oxygen, creates the desire to breathe and, by getting rid of carbon dioxide in this way, snorkellers are more likely to suffer a "blackout" through hypoxia (shortage of oxygen).

Ice Diving

See No Clear Surface.


See Accidents/Incidents


Membership of the BSAC automatically gives worldwide Public Liability insurance cover of up to 5,000,000 when the member is engaged in diving or diving related activities. This cover is available to all BSAC members regardless of where they are domiciled, and cover applies as soon as membership is confirmed/renewed. This is considered to be the earlier of when the Branch issues a temporary membership receipt to that member, or when the membership  details are included on the BSAC"s membership database at BSAC  Headquarters.

Cover also includes any qualified diving guests of the insured, prior to becoming a full member, whilst participating in the activities of any Branch to which the policy applies, as well as any intended member undergoing preliminary training. Both of these extensions are naturally subject to certain time limits,  and further details on the policy can be obtained from BSAC Headquarters.

Cover is not restricted to only BSAC organised events or when the member is diving with other BSAC members. The general rule is that if the member is also a member of another diving association and is participating in a dive organised by this other association, then that association"s own public liability insurance policy should respond. If mixtures of individuals from various organisations are diving with an independent organiser then the BSAC policy will respond to that BSAC member.

Organised social events such as shows, bOrganised social events such as shows, barbecues, bonfire parties and other fund raising events are covered. However the policy does not cover personal or Branch diving equipment or boats, and it is a constitutional rule of the BSAC that all boats used for Branch diving, whether privately owned or not, must be insured for Third Party risks with a minimum indemnity limit as recommended by the BSAC,  currently at 5,000,000. If water skiing is included in Branch activities, additional cover is also required.

It is important to note that potential incidents should be reported to the BSAC using the BSAC Incident Reporting System, and further details on this system, and the insurance policy itself can be obtained by contacting Technical Support Services at BSAC Headquarters.


With the exception of requirements relating to cylinders (see Cylinders) and the law which protects historic wreck sites, there are no laws or government regulations in the UK about the way in which the sport of diving must be conducted.

However, if you dive for money or reward, even using recreational techniques and equipment, you are considered to be a professional diver and are subject to the requirements of the Diving at Work Regulations 1997. These regulations require a diving medical issued by a medical examiner approved by the Health and Safety Executive (HSE) and impose detailed safety requirements on all diving operations.

Amateur divers must be aware that any job of work carried out for anything other than essential expenses e.g. petrol or air costs, would be considered subject to the requirements of the Regulations. It does not matter whether the money or gifts are presented to the divers or their Branch, this would still be seen by the HSE as diving at work. Even jobs of work undertaken for true expenses are seen by professional divers as "stealing their work" and will often be a source of aggravation.

The regulations recognise that different techniques are used by the different sectors of the diving industry, and there are five separate Codes of Practice covering Offshore Diving, Inshore Diving, Scientific and Archaeological Diving, Recreational Diving and Media Diving.

Divers working professionally have to comply with the requirements of the relevant Code of Practice. Those teaching sport diving professionally must comply with the Recreational Diving Code of Practice.

Appropriate BSAC qualifications have been approved by the HSE for activities covered by this Code.

Medical Examination

It is strongly recommended that all divers should undergo a medical examination before beginning training with underwater breathing apparatus, although a chest x-ray would not normally be required. This recommendation is a rule for members of the BSAC.

Repeat medicals should be taken every five years up to the age of 40, every three years to the age of 50, and annually thereafter. Branch Diving Officers should ask for proof of current medical fitness when members transfer to them from another Branch.

Any member who has been the subject of a decompression accident must not commence diving again until medical clearance has been obtained from a BSAC Medical Referee, or another NDC Approved Consultant.

Potential new members who are undergoing the 'Experience Scuba' introductory course should be asked to sign a disclaimer, which states they have not suffered from diseases or conditions which would make aqualung diving hazardous.

Mixed Gases

Breathing gases containing nitrogen and oxygen in proportions other than that of air may be used by properly trained and qualified BSAC members. Mixtures containing other gases (e.g. helium, hydrogen) are not recommended for use by recreational divers.(see Nitrox)


Neutral Buoyancy

Neutral buoyancy is achieved when the diver is able to remain in a static position in the water and rises or falls as a result of breathing in and out. Comfortable diving means the achievement of neutral buoyancy, if required, at any stage of the dive. Correct weighting is critical to gaining neutral buoyancy easily, the diver should carry just enough weight to hold a 6m. decompression stop with a nearly empty cylinder.

The NDC strongly recommend that where a drysuit is being worn, the drysuit is used to maintain neutral buoyancy underwater.

Night Diving

Night diving, especially in tidal waters, requires very careful planning. Each diver should have a working torch otherwise the dive should be terminated. An efficient system of marking the point of exit must be employed. Care must be taken with diver to diver signals to ensure that the torch is not shone directly into the diver's eyes.

Nitrogen Narcosis

Nitrogen Narcosis decreases a person's ability to cope with emergencies, slows down reaction and realisation time and increases the risk of an accident. There is strong evidence to suggest that 40m should be regarded as the maximum depth for most sports divers, as below this depth narcosis problems can become debilitating.


The use of Nitrox (nitrogen / oxygen mixtures where the oxygen content is greater than that of air) as a breathing gas can provide a safety benefit in terms of a reduced risk of decompression illness, or enable longer dives times / shorter decompression stop requirements with no added risk. The use of Nitrox has certain disadvantages which require training and suitable equipment to minimise the risk.

Properly trained and qualified BSAC members are permitted to use Nitrox on Branch dives, with the approval of the Dive Marshall. The BSAC provides a range of courses and qualifications in Nitrox diving.

The NDC recommends a maximum partial pressure for oxygen exposure when diving of 1.4 bar. This figure will normally determine the Maximum Operating Depth for any Nitrox mixture. However, for the standard mixtures of 32% and 36% oxygen, Maximum Operating Depths of 35m. and 30m. respectively are permitted. Failure to observe the Maximum Operating Depth for any gas mixture may have fatal consequences due to the onset of oxygen toxicity. (See Cylinders (Nitrox)).

No Clear Surface

(Cave Diving, Ice Diving, Diving inside Wrecks)

Members wishing to dive in caves should contact the appropriate cave diving organisations, as this is very specialised diving, in terms of technique and equipment, and is not covered in BSAC diver training.

Diving under ice should only be undertaken with a surface party of at least two. This allows one to tender the divers, while the other is free, if required for any reason, including an emergency. One of the divers must be securely roped to the surface, if diving in pairs, and contact between them should be by means of a buddy line.

Wrecks should not be penetrated without proper training and equipment. (See Wreck Diving)

Odd Numbers

It is very strongly recommended that diving in 'odd numbers' be avoided, as the 'odd man out', to some extent, is without a buddy.

(See Buddy Diving).


The administration of 100% pure oxygen following a decompression accident is recognised as an effective FIRST AID TREATMENT and may result in much less serious injuries. It SHOULD NEVER be regarded as a substitute for recompression, which is the only effective treatment in such cases. Members who have taken part in appropriate training courses and who have approved equipment, are recommended to use oxygen to treat divers showing symptoms of decompression illness, while they are waiting for recompression treatment. Where 100% oxygen is unavailable as a therapy gas, Nitrox mixtures may be used, although the benefit will be much less than that of pure oxygen.

The use of Nitrox mixtures containing up to 80% oxygen is permitted for diving by properly trained and qualified BSAC members. Mixtures containing more than 80% oxygen are NOT recommended for use by recreational divers. (See also Rebreathers).

PFO (Patent Foramen Ovale)

During pregnancy the right and left sides of the foetal heart are connected. The hole between the right and left sides is known as the Foramen Ovale. Normally this should heal over after birth, separating the venous and arterial blood supplies passing through the heart. However in a proportion of the population (perhaps 25%) this hole does not close up completely, resulting in a Patent Foramen Ovale (PFO). The consequence for divers is that having a PFO can increase the risk of decompression illness. This occurs as a result of bubbles in the venous circulation (which would normally be filtered out in the lungs) shunting across to the arterial circulation, where they continue to expand in size.

Pots and Markers

Dive well away from fishermen's buoys, pots and pot markers, unless there are special circumstances.


Medical evidence as to the safety of diving whilst pregnant is not conclusive. However there is evidence that deep diving may cause harm to the foetus. Certainly decompression illness and its subsequent treatment could be harmful to the foetus. Consequently if a woman is pregnant, or is trying to become pregnant, she is strongly advised not to dive.

Those women who decide they wish to continue to dive whilst pregnant, or trying to become pregnant, should only undertake shallow dives, ideally less than 10m and no deeper than 20m, and remain well inside no-stop times. Even at shallow depths there remains a risk of pulmonary barotrauma which could require recompression treatment and cause harm to the foetus.

If a woman discovers she is pregnant and has been diving during the pregnancy, she is advised to discuss her case with a BSAC Medical Referee. The scientific evidence is not clear cut and ultrasound studies, together with other indications, may be useful to allay any fears and help in the decision as to how the pregnancy should be managed.

Propeller Guards

A propeller guard, fitted to an outboard motor, gives a degree of protection from injuries to divers. Before fitting a propeller guard, take note of the manufacturer's recommendations and instructions, as it is possible to cause stress to the gear box and low end of the engine. Some loss of power may result from fitting a propeller guard.

Qualifying Dives

Open water qualifying dives should be made under the guidance of a Branch instructor or approved Dive Leader. Each dive should increase the diver's experience of differing underwater conditions and where appropriate follow the format laid out within the training scheme.


Semi-closed circuit sport diving rebreathers are the only type of rebreather currently permitted for use on BSAC Branch dives. Members wishing to use a rebreather for recreational dives must hold a recognised rebreather qualification and register this qualification with BSAC Technical Support Services at BSAC HQ.

Current BSAC rules and recommendations for safe diving are equally applicable to diving with a rebreather. Rebreather divers should also follow the additional guidelines for diving with rebreathers that the BSAC have published, which in summary are as follows:

         The maximum depth for BSAC rebreather diving is 40 metres.      

         A rebreather is not to be used by an instructor whilst teaching or assessing an open circuit diver.     

         Always prepare and use the rebreather following specifications set by the manufacturer.

         Discuss your intended dive plan with your buddy and inform the Dive Marshal of your intentions.

         Review/modify your buddy check procedure to accommodate the rebreather layout.

         Ensure that your buddy understands the operation of your rebreather. Emphasise the opening and closing of the mouthpiece to maintain gas in the loop in the event of a rescue.

         Always carry a suitable alternative gas source for yourself and your buddy.

         The only permissible gas for use in a rebreather on BSAC dives is Nitrox. The maximum oxygen percentage allowed is 80%.

         Carry a means of indication on the surface. Reduced bubbles will make boat cover difficult if no marker is used.

         Consider the role of the rebreather in First Aid following a DCI incident within the diving party: a rebreather allows prolonged enriched air to be made available to the conscious casualty.

Re-Entry Decompression

If a diver misses planned decompression stops, no attempt should be made to enter the water again in order to complete them. In this situation the diver is increasing the risk of decompression illness.

Repeat Dives

The BSAC 88 Decompression Tables should be used for planning and performing repeat dives. Where two or more dives are being made the same day, it is good practice to carry out the deepest dive first. You should also take care if you are involved in several days of diving deeper than 30m. It is possible to accumulate excess nitrogen over this period, and apparently 'innocent' dives, carried out near the end of the period of diving, can cause decompression illness. It is therefore recommended that any dive series involving consecutive days diving to 30m+ is limited to four days, after which a 24 hour break should be taken.

(See BSAC 88 Decompression Tables)


Divers should take great care with the use of ropes underwater, especially using reels as distance lines from shot lines. Reels for SMB use should float independently, have a quick release system such as a bayonet fitting snap lock and divers should be taught how to use them. When divers do get into difficulties on ascent it is often the best course of action to ditch the reel so that both hands are free to deal with the situation. When using a reel and line as a bottom distance line, we recommend that a reel and line which sinks is used and that when deploying line, hold the reel and line away from the body and especially the legs. It should also be recovered from in front of you. Never let a bight of line develop in front of you; slow down and wind in.

Separated Divers

If divers become separated underwater, a brief attempt (approx. 30 seconds) to re-locate should be made, after which the divers should surface. If the dive is subsequently re-commenced appropriate decompression planning must first be carried out.


See Assisted Ascents.


Divers should be completely familiar with the standard code of visual signals and should give them accurately and clearly. All signals should be acknowledged. The 'Come and get me' signal by a diver at the surface is to be used only for distress, and not as a 'Pick me up' signal.

Solo Diving

There are occasions, e.g. in nil visibility or when working underwater, when the 'buddy' system is ineffective. On these occasions a solo dive may be required, with the diver being securely roped and in constant rope communication with a surface 'tender', who should be a diver himself.

The rope must be securely fastened to a suitable object on the surface. Communicating signals must be fully understood and a fully kitted, roped, 'stand-by' diver must be available in the event of an emergency.

Stand-by Divers

On the majority of dives your stand-by diver is your buddy. A stand-by diver is usually only required when a solo dive, using a rope tender, is in operation.

Surface Marker Buoy (SMB)

SMBs should be used in significantly moving water, when operating well offshore and in areas with heavy surface traffic. There may be times, other than these stated, when their use might be deemed prudent by the dive marshal. It is essential that correct training is given to new members in their use, as for any unfamiliar equipment. In some situations e.g. wreck sites with slack water, they are unnecessary and can actually be a hazard to the diver.

Tangle Nets/Gill Nets

Indiscriminate fishing, particularly on wreck sites, with difficult-to-see monofilament netting, is a real hazard around the British coast. Experiments have shown that the average diver"s knife is very ineffective should the diver become entangled. A curved blade "dinghy" knife, with a blunt end, is probably the most effective type and needs to be worn on the arm. A knife with a sharp point could lead to a diver stabbing himself when in difficulties. Small shears or scissors are recommended as an effective tool for cutting netting. Once caught in netting, it is advisable to partially inflate your lifejacket, so you rise inside the net, putting it under tension and making it easier to cut. The positive buoyancy will also help to "tear" you away. If your buddy is free of the netting he may be advised to cut you out, still enmeshed, and worry about completing the job on the surface.


The success of any sea dive depends on accurate, local, tidal predictions for the dive site you wish to visit. Admiralty charts give accurate large scale predictions and should be used in conjunction with the relevant local tide tables. Tidal Stream Atlases are also useful and are available for the UK and many other sea areas throughout the World.

VHF Radio

VHF radios are a valuable aid to safety at sea and, together with suitable waterproof housings, are frequently used in small boats.

Radios should only be used by someone who has passed the appropriate exam and when the radio is licensed. All divers are recommended to attend a BSAC VHF Course available through the Coaching Scheme, where correct radio procedures are taught.

It is an offence to use Marine VHF radio from the land, so your shore party is not allowed to use one.


Acquiring an accurate weather forecast for your dive site can save a lot of unnecessary travelling expense and can mean the difference between a controlled successful dive and a risky experience.

BBC TV News Bulletins are always followed by a UK forecast with easy to understand symbols. Some daily newspapers carry a good forecast with weather map, and the Maritime and Coastguard Agency always has an up to date forecast. RAF stations have a meteorological station and are usually very helpful. The Shipping Forecast on Radio 4 is another very useful source, whilst the Meteorological Office (Met Office) provides a telephone message and fax back service: its helpine is 01344 854153.


Weightbelts, when used, should always be fitted with a reliable quick release and fitted so that it will always fall clear of other equipment when released. You should be practised in releasing your weighbelt and should also make sure that your buddy is well briefed and fully familiar with your release mechanism. If the buckle is of the same type as on the cylinder harness, it is wise to wear it so that it operates in the opposite direction.

Wreck Diving

Wreck diving is one of the most popular forms of diving and requires extra safety precautions if divers venture inside the wreck. Many steel wrecks are in a dangerous state of decay, and loose overhead objects or steel plates are a real hazard. Never venture deep inside a wreck without ensuring your route to clear water is certain, and use a reel and line secured to the outside of the wreck to mark your return route. Avoid excessive finning inside a wreck as sediment stirred up is very slow to settle, due to lack of tidal flow. Always allow an adequate reserve of air at the end of your dive and never run down your air supply by attempting to remove an artefact. Never try to lift heavy objects from wrecks using your BCD and/or drysuit.  



More and more people are taking to the water. Some for recreation; some to earn their living. This code is designed to ensure that divers do not come into conflict with other water users and sets out some guidelines which should be observed alongside the regulations relating to Marine Nature Reserves.

Before leaving home

Contact the nearest BSAC Branch or the dive operator local to the dive site for their advice. Seek advice from them about the local conditions and regulations. If appropriate, have the correct chart and tide tables for the area to be dived.

On the beach, river bank or lakeside

1.       Obtain permission before diving in a harbour or estuary or in private water. Thank those responsible before you leave. Pay harbour dues.

2.       Try to avoid overcrowding one site, consider other people on the beach.

3.       Park sensibly. Avoid obstructing narrow approach roads. Keep off verges. Pay parking fees and use proper car parks.

4.       Don't spread yourselves and your equipment since you may upset other people. Keep launching ramps and slipways clear.

5.       Please keep the peace. Don't operate a compressor within earshot of other people - or late at night.

6.       Pick up litter. Close gates. Be careful about fires. Avoid any damage to land or crops.

7.       Obey special instructions such as National Trust rules, local bye-laws and regulations about camping and caravanning.

8.       Remember divers in wet or drysuits are conspicuous and bad behaviour could ban us from beaches.

In and on the water

1.       Mark your dive boats so that your Club can be identified easily. Unmarked boats may become suspect.

2.       Ask the harbour-master or local officials where to launch your boat - and do as they say. Tell the Coastguard, or a responsible person, where you are going and tell them when you are back.

3.       Stay away from buoys, pots, and pot markers. Ask local fishermen where not to dive. Avoid driving through rafts of seabirds or seal colonies etc.

4.       Remember ships have not got brakes, so avoid diving in fairways or areas of heavy surface traffic and observe the 'International Regulations for the Prevention of Collisions at Sea'.

5.       Always fly the diving flag when diving, but not when on the way to, or from, the dive site. Never leave a boat unattended.

6.       Do not come in to bathing beaches under power. Use any special approach lanes. Do not disturb any seal or bird colonies with your boats. Watch your wash in crowded nchorages.

7.       Whenever possible, divers should use a surface marker buoy.

On conservation

1.       Never use a speargun.

2.       Shellfish, such as crabs and lobsters, take several years to grow to maturity; over-collecting in an area soon depletes stocks. Observe local Byelaws and restrictions on the collection of animal and plant specimens. However the BSAC recommends that you do not collect shellfish, but if you must collect, only take mature fish or shellfish and then only what you need for yourself. Never take a berried female (a female with eggs), this is stock for future years. Never sell your catch or clean it in public or on the beach and do not display your trophies.

3.       Ascertain and comply with seasonal access restrictions established to protect seabirds and seals from disturbance. During the seabird breeding season (1st March 1st August) reduce noise and speed near seabird breeding sites. Do not approach seal breading or haul-out sites. Do not approach dolphins or porpoises in the water.

4.       Be conservation conscious. Avoid damage to weeds and the sea bed. Do not bring up sea-fans, corals, starfish or sea urchins - in one moment you can destroy years of growth.

5.       Take photographs and notes - not specimens. 

On wrecks

1.       Do not dive on a designated protected wreck site. These are indicated on Admiralty Charts and marked by buoys or warning notices on the shore nearby.

2.       Do not lift anything which appears to be of historical importance.

3.       If you do discover a wreck, pinpoint the site, do a rough survey and report it to the Nautical Archaeological Society, who will advise you.

4.       If you do not lift anything from the wreck, it is not necessary to report your discovery to the Receiver of Wreck. If you do lift, you must report even if you, or your Branch, owns the wreck.

5.       If your find is important, you may apply for it to be designated a protected site. Then you can build up a well qualified team with the right credentials and proceed with a systematic survey or excavation under licence without outside interference.

  Don't let divers down keep to the diver's code

The Divers Code of Conduct that is set out immediately above was developed by the BSAC many years ago, and is still relevant to all divers today. However environmental issues are of greater concern to all water users today than ever before, particularly when this Code was developed, and so during 1999 the BSAC will be actively developing its environmental presence by the development of the following policies. 

         To provide education in environmental awareness, understanding and enjoyment

         To promote Branch participation in environmental schemes and events     

         Highlight current environmental issues, and work with other environmentalists in order to provide a united approach to deal with these issues.

         To further develop and update the Divers Code of Conduct