1. Diving war graves

2. Removing artifacts from wrecks

• What happens
  • Sport divers and salvagers dive on wrecks and remove artifacts of interest including large, brass, parts of the ships steering and navigation equipment, ammunition, bottles, plates and samples of the cargo
  • Of course, legitimate salvage by the owners does occur: not every broken up ship has been vandalised by divers. This sort of salvage can cause considerable damage to ships and often involves removing large non-ferrous components such as propellers and condensers.
• Arguments against it
  • Most wrecks and their cargoes are owned by someone. So, removing things from them is theft.
  • Some wrecks are war graves. Relatives of the dead feel removing things from the site or even diving the site is a desecration.
  • Some wrecks are legally protected for their archeological value.
  • Its dangerous. Sometimes unexpended ammunition is brought to the surface.
  • It removes things of interest that other divers would have seen if they had been left down there.
  • The artifacts are often not put to good use - they rot in someone's garden shed rather than go on display in a museum
• Arguments that defend it
  • Can't really think of anything that's right with breaking a ship apart to get at small brass fittings or bringing up ammunition
  • Bringing up small bottles and other interesting items from the cargo seems pretty harmless 

3. Taking shell fish from dive sites

• What happens
  • Sport divers catch lobsters, crabs, mussels, oysters and scallops underwater and take them home to eat
• Arguments against it
  • Certain species, such as crayfish, a high priced spiny lobster, are no longer seen on the south coast of England. They were fished out, by divers who sold them to restaurants, in the 1960s.
  • By constantly removing animals from well known dive sites we effectively eliminate them from those sites.
  • By removing animals from dive sites other divers don't get to see them.
• Arguments that defend it
  • Surely small numbers of divers, taking for their own consumption, can't be making a big impression on the survival of huge numbers of shell fish?

4. Divers compete with fishermen

• What happens
  • Sport divers catch lobsters, crabs, mussels, oysters and scallops underwater and take them home to eat
• Arguments against it
  • Fishermen depend on the sea for their living.
  • Stocks are limited.
  • Fishermen are already hard pressed.
• Arguments that defend it
  • Surely small numbers of divers, taking for their own consumption, can't be really be making much of an impact on fishermen's livelihoods
  • Why should divers buy shell fish from fishermen, via Sainsbury's,  when they can collect their own? The animals aren't owned or farmed by the fishermen.
  • Taking shell fish while diving is relatively environmentally efficient. Some commercial fishing practices are very wastefully and destructive, such as
    • dragging chain nets across the sea bed for scallops - destroys whole habitats
    • netting but throwing back large numbers of unmarketable dead fish - unnecessarily kills many fish

5. Divers sabotage commercial fishing gear

• What happens
  • It has been known for lobster pots and nets to be damaged by divers underwater either to free or steal the fishermen's catch
• Arguments against it
  • Its an offence - criminal damage.
  • Fishermen have the right to use the sea.
  • Fishermen depend on the sea for their living.
  • It causes bad relations between divers and fishermen

6. Divers and dive boats cause many Coastguard and Lifeboat callouts due to their lack of care and skill 

• What happens
  • Club dive boats and diving groups have mechanical failures and diving emergencies that are only resolved by the Coastguard or Lifeboats 
• Arguments against it
  • It wastes emergency service resources and goodwill.
  • It uses resources that could be used in more needy cases
  • It shows divers in a bad light.

The next two sections explore some of the controversial topics which cause long and heated discussions in diving circles.

The reason these topics are difficult is the strengths of the arguments for and against them:

• Arguments against:
  • they increase diving risks
  • there are better ways of solutions to the problems they attempt to solve
• Arguments for:
  • the increase in risk has been calculated and compensated for by other measures or extra care
  • skilled, experienced and practiced divers should be able to cope

Planning and training

1. Buddy Breathing

• Why it's done:
  • It's a valid way of air sharing that may be needed if other easier and more secure alternatives are not available
• How it's done:
  • Two divers share the same DV after one has run out of air
  • They must be practiced and calm if the technique is to succeed
• What's the problem with it:
  • Its unlikely that inexperienced or panicked divers will be able to do buddy breath successfully and ascend safely
  • There are better ways of dealing with out of air emergencies:
    • AAS sharing
    • independent air supply
  • Buddy breathing is more difficult and therefore needs more practice so some people have it "imprinted" on their thought processes and will do it in an emergency even when AAS is available
• How you can avoid or reduce the effects of this problem:
  • Make AAS sharing or using your own independent air supply your first choice in an out of air emergency
  • Practise AAS and Buddy Breathing regularly
  • Get an independent air supply (pony or twin set)

2. Free Ascents/Controlled Emergency Swimming Ascents

• Why it's done:
  • It returns the casualty to the surface quickly where he or she can breathe and help can be given.
  • It's a valid way of dealing with some shallow water, urgent, emergencies such as out of air.
  • It does not rely on a buddy to help the casualty
• How it's done:
  • The distressed diver swims to the surface quickly.
  • The diver may deliberately drop his or her weight belt to ensure he or she floats on the surface.
  • It's likely only to be used in these circumstances:
    • The casualty's buddy is unable to provide air
    • The casualty is diving solo
• What's the problem with it:
  • If the diver does not exhale strongly, he or she will burst a lung.
  • Its likely to provoke Decompression Sickness in all but the shallowest and shortest dives.
  • There are better ways of dealing with out of air emergencies even when solo: independent air supplies
• How you can avoid or reduce the effects of this problem:
  • Get an independent air supply (pony or twin set)
  • Stay close to your buddy so that AAS sharing is possible

3. Diving without an independent air supply

• How and why it's done:
  • Some people believe that a buddy with an octopus is sufficient backup to do deco diving
  • Others believe that too much unnecessary equipment invites problems underwater and so only use the minimum necessary
• What's the problem with it:
  • Deco diving involves more risk than no-stop diving
    • generally you dive deeper and stay longer - so you consume more air
    • you need to carry out deco stops at the end of the dive - this requires extra air
  • There is less leeway for mistakes when doing deco diving and if you fail do do your deco stops, there is a much increased risk of Decompression Sickness 
  • You and your buddy must plan to double your end of dive air reserves in case one of you goes Out Of Air at the end of a dive requiring an ascent from depth and long stops

• How you can avoid or reduce the effects of this problem:
  • have a regular buddy who understands your diving habits, whose equipment you are familiar with and who you know is practiced in the emergency drills
  • practice your own emergency drills - especially air sharing
  • stay close to your buddy
  • plan and execute your dives more carefully
  • avoid deep dives or ones with decompression stops

4. Breathing one cylinder of a twin set until its empty

5. Solo diving

• How it's done:
  • Rather than diving with another diver in what is called the Buddy System, some divers prefer to dive alone
• Why it's done:
  • In certain situations it is safer - for instance, in very low visibility or a confined space - but special precautions are called for (see below)
  • Divers who enjoy a certain type or style of dive may not be able to find a buddy with a similar outlook
  • Some people think inexperienced, badly trained or unpractised buddies are a greater risk than diving solo
• What's the problem with it:
  • a buddy can be a great help in an emergency
  • if a diver loses consciousness or gets caught in nets or lines, a buddy's help is essential
• How you can avoid or reduce the effects of this problem:
  • if diving solo because of poor viz or a confined space use the technique described in the Sport Diver manual:
    • roped diver
    • rope signals
    • experienced rope tender
    • fully kitted standby diver
  • have a independent air sources
  • make sure your kit it is good working order
  • arrange your kit to reduce snags on nets and lines 
  • carry efficient rope and line cutting tools

6. Doing reverse profiles on repetitive dives

• How and why it's done:
  • Reverse profiles are repetitive dives where the second dive is deeper than the first
  • Factors such as the times of the tide, the distance to the site and the type of site sometimes make reverse profiles appealing
  • Many people think that as modern dive computers, with some extra conservatism applied, are able to accurately and dynamically calculate a diver's decompression requirements no matter what the profile
• What's the problem with it:
  • Reverse profiles are thought to be a factor causing in Decompression Sickness
  • Some decompression models such as decompression tables actively discourage reverse profiles
• How you can avoid or reduce the effects of this problem:
  • There are many other factors that influence the risk of Decompression Sickness: doing deco diving, short surface interval, hydration, fatigue, fitness etc - make sure you arrange your diving day so that none of those other factors increase your risk of DCS
  • build in extra conservatism into your plan: do longer stops, use nitrox, have a longer surface interval

7. Using prescription drugs before diving

• How and why it's done:
  • Divers suffering from ailments, such as sea sickness or nasal congestion, routinely take drugs to reduce the effects of those conditions whilst diving
• What's the problem with it:
  • Some prescription drugs, in some cases, used by some people, may increase the risks of Decompression Sickness.
  • Some drugs have powerful side effects - when you're diving you need to be at your most fit and alert
• How you can avoid or reduce the effects of this problem:
  • Get advice from a diving doctor before using prescription drugs whilst diving
  • Don't mix your drugs

8. Diving in threesomes

• How and why it's done:
  • If the diving group has an odd number of people a buddy group of three is formed 
• What's the problem with it:
  • In the low visibility and high current conditions that we dive in there is an increased risk of one of the group getting into difficulty or separating without the others noticing
  • The buddy system is one of our most important safety measures: threesomes weaken it
• How you can avoid or reduce the effects of this problem:
  • Maintain contact using a buddy line between 2 or even all 3 of the divers
  • Be more careful in planning, briefing and monitoring

Diving techniques and equipment

1. Controlling your buoyancy underwater with both BC and dry suit

• Why it's done:
  • Some divers use a BC to reduce the volume of air in the dry suit and scope for air migration in the dry suit
• What's the problem with it:
  • Using two buoyancy systems underwater causes twice as much buoyancy control work and increases the risk of losing control of your buoyancy
• How you can avoid or reduce the effects of this problem:
  • In the normal course of diving only use one buoyancy system - preferably the dry suit - completely vent the other

2. Ascending from a dive using a deco buoy rather than a shot line (if there is a shot down)

• Why it's done:
  • to allow the divers to explore a dive site more fully
  • to make the dive easier and more flexible to plan and execute
  • if the current picks up whilst diving, the shot may become difficult to use, so the divers send up a buoy to mark their ascent position
• How it's done:
  • either, when the divers are ready to ascend, they let off a deco buoy using a reel from the bottom
  • or, close to their deco stop depth, they send up a buoy held down by a spool of weighted line
• What's the problem with it:
  • in many cases it's more convenient for the boat cover to find and collect divers if they all return to the shot
  • divers on deco buoys drift with the current - there is a risk of drifting out of sight from the boat
  • divers ascend at different times and therefore become dispersed - increase the risk of the boat losing divers
  • deco buoys are not perfectly reliable - reels can jamb and deco buoys can deflate - but so can shot buoys be dragged under in strong currents
• How you can avoid or reduce the effects of this problem:
  • agree the method of ascent with the boat cover prior to diving
  • identify yourself on the buoy
  • be prepared from reel jambs - use two reels or tie the reel down before setting off the deco buoy

3. Carrying too much weight on your weight belt

4. Securing your weight belt to your BC

• Why it's done:
  • To reduce the risk of losing a weight belt (and the emergency that causes)
• How it's done:
  • The weight belt is clipped to the BC 
• What's the problem with it:
  • Dumping a weight belt is a useful means of rescue that almost guarantees the casualty gets to the surface where further help can be given
  • Clipping the weight belt to the BC reduces the likelihood of the casualty or rescuers releasing the weight belt in a crisis
• How you can avoid or reduce the effects of this problem:
  • Use a secure buckle on the weight belt
  • Consider using weights that are integrated into your BC in a way that is both secure and quick-release
  • Brief your buddy carefully if you do secure the weight belt to the BC