Contributed By Fernando Ferreira
Diver safety can be narrowed down into three main groups: Safe Code of Practice, Rescue & Recovery and Basic First Aid Skills and Procedures. “SafeCode of Practice” is what we’ll be chatting aboutin this issue, hopefully to shed some light on the importance in safe diving practice.
Safe Code of Practice
Safe code of practice begins with your approach towards the sport. You require a positive, yet yielding mindset and attitude towards breath hold practice. Pushing too hard too soon, or succumbing
to peer pressure may lead to negative results in your progress. We are all individuals and progress at different rates. Therefore allow enough time for adaptation, and never place unrealistic expectations on personal performance.
A good idea is to attend diver education programs and workshops regarding freediving, spearfishing and general safety. Do a first aid course, listen and learn from the more experienced divers. There is no substitute for experience. Ask for help from knowledgeable people when in doubt, or join a reputable dive club to try to learn as much as possible through interacting with like minded
people; even research for your own experience. It’s good practice to always dive or train within the “assumed” safety parameters. Try to train or dive with a buddy, and have an emergency plan in place.Rescue & Recovery techniques and procedures, as well as basic first aid skills and procedures should be well rehearsed, and all people taking part in a training session or social outing should be aware of this practice. Diving in a responsible and safe manner will save lives.
The Buddy System
This subject is often debated with much passion amongst freedivers and spearos. There are two schools of thought and both have valid points.
Freedivers swear by the “Buddy System”. A freediving event is normally very structured and controlled, with all the safety and emergency plans in place. Diving is normally hosted in a safe and
controlled environment with a guide rope dropped to a designated depth. A freediver is then hooked onto this rope by means of a leash or uses a sled for extremely deep dives. The procedure of a count down is performed by a dive supervisor for the freediver to know how much time he/she has left for the breathe up. There are safety freedivers on the surface which go and meet the ascending freediver at approximately -10m, and escort them through the danger zone. In the event that he/she succumbs to a SWB, the safety freedivers are there to render immediate assistance if anything shouldgo wrong, and to revive the victim on the surface.
The victim is then stabilized and is not allowed to dive for a minimum of 24hrs. There are also safety divers on scuba involved in these events. “Tech Divers” are the most desirable crews to work with because of their depth range, their meticulous approach to detail and knowledge regarding diving matters. These divers normally wait for the descending freediver at the target depth, the “OK” sign is exchanged between both divers, and then the freediver begins their ascent. This is great when it comes to structured and controlled events but, unlike freediving,spearfishing is an extremely dynamic activity. Spearos become focused in their personal space, strategy and hunting technique; babysitting others simply becomes something they tend to lose focus of. In a very short space of time, buddy pairs are often drifting 30+ meters away from each other. Their point is, “What’s the good of the diving buddy system if most of the time we can’t see each other underwater?” This is a valid point indeed.
Many spearos have adopted the “diver up / diver down” method, which works well. However careful planning and extreme self discipline has to be exercised if this kind of “buddy system” is going to work for spearos, especially if the fish are running.
Another area of debate is “safety distance required when dealing with loaded spearguns so that accidents may be avoided.” In low vis, you will lose sight of your dive buddy if you maintain a safe
distance between each other. Hence the dilemma facing us here is, “does the dive buddy system suit my personal diving activity? We are all in agreement that the buddy system is effective, provided that dive buddies maintain visual contact and are in close proximity in order to minimise reaction time in the event that one of the divers gets into trouble. If you are however in the water, and you have no visual contact with your dive buddy, the effectiveness of the buddy system is lost. The best alternative to this dilemma is to dive off a boat. The top man must be someone with sound knowledge of the activity and who maintains a sharp eye on the divers. Unfortunately the top man can only observe divers
which are on the surface, and so the arguments carry on. In the end, the choice of diving the “buddy system” lies purely on the individual’s shoulders, and no amount of rules and “do’s & don’ts” can force anyone to dive or train with a buddy.
The Dive Buddy
• Be selective of your dive partner.
• A good dive partner is someone knowledgeable and should be on par with your diving skills.
• A good dive partner is someone which has the same mind set and goals as you have.
• Both you and your buddy should be trained in
First Aid and CPR and a plus point is if both of you
practice rescue and recovery drills.
• A good dive partner is someone you can trust.
In my opinion, if your dive partner doesn’t posses
most of these qualities, you may as well be diving
Some of the “NEVERS”
Never dive or carry on training after a Samba, Black Out or Cyanosis.
• Loss of Motor Control Skills (LMC – Samba) or loss of consciousness (BO) means you slipped over the edge and should be taken seriously. All diving should be terminated immediately and a
24 hour rest period should be enforced.
• In the case of a Samba, the body enters an elevated state of Hypoxia and uncontrollable physical movement is displayed by the apneaist,often referred to as a “Samba,” or “Going Brazilian.” This is a term of endearment used by freedivers when you have overstepped the critical apnea threshold. Enforce a 24 hour rest period before diving again.
• Black Out (BO) is the sudden loss of consciousness caused by oxygen deprivation to the brain. If you lose consciousness and there is no one to rescue you, drowning will follow shortly. The black outoccurs quickly, insidiously and without warning. The victim drowns without even knowing it.
• Cyanosis is quickly identified by the “purplish blue” lip colouration. The body enters a state of Hypoxia – this is a clear indication you are on the knife edge and about to slip into the dark side.
This condition predisposes an apneaist to a black out.
• This is simply a dangerous practice. It increases blood pH which affects the Bohr Effect and BLUE WATERS SILENT DEATH were two pilot articles to introduce a series of articles regarding
DIVER SAFETY. With more people turning to recreational freediving every year, the need for safety measures in this extreme sport became necessary with every passing incident. Through
the years, many knowledgeable people such as medical researchers, doctors, professional divers and professional freedivers have contributed toward safety in apnea sport diving
through experience, medical research and knowledge. The aim of these articles is to try and help making apnea sport diving a little safer to practice. However it can not guarantee immunity to any mishap which may occur while practicing this extreme sport.suppresses the natural breathing reflex. For more information on the subject, refer to the previous USM issue, article on hyperventilation in “BLUE WATERS, SILENT DEATH PART 2” and why it is counter productive.
Never ride the flexibility of your eardrum.
• Equalise on descent only, and never forcefully. Avoid a reverse block – this action could hurt the tympanic membrane, which in turn could spoil the rest of your diving for the day. If you are
unable to equalise, abort the dive immediately. If the inability to equalise persists consecutively, terminate the diving for the day because you may forcefully push the limit and burst an eardrum.
The immediate sign of a burst eardrum is pain,vertigo and nausea.
Never freedive after a scuba dive.
Henry’s Law: – When pressure is increased, the quantities of gas absorbed into the tissue of the body also increases. This is what causes “narcing” (Nitrogen Narcosis) in scuba diving, and can lead
to the “bends” (decompression sickness) if “deco stops” are not adhered too.
• Nitrogen is absorbed into the tissue while scuba diving, hence the need for “Dive Tables,” safety / deco stops when ascend on scuba and rest periods between dives, if you are performing
repetitive dives that day. If you freedive after scuba diving, the nitrogen bubbles in your system are recompressed as you descend, and expand rapidly when ascending from a freedive. (no
chance to perform deco stops) This practice can lead to decompression sickness as well as SWB. A good rule of thumb is to allow at least 12 hours. of de-gassing time before freediving.
My personal recomendation is 24 hours to be safe.
Never exhale underwater.
• The less buoyant you are, the greater the effort required to reach the surface. The increased effort burns up larger amounts of oxygen.Being in this predicament increases the risk
• By exhaling underwater, you decrease the air volume in the lungs, giving you less air to equalise the ears and mask and thus limiting depth.
• Boyle’s Law: Gas is compressible under pressure and expands when pressure is released. As you ascend, the lungs begin to expand, drawing the oxygen which was diffused into the blood stream back to the lungs rapidly as the diver ascends. Air which is diffused back into the lungs is loaded with CO2 and soon circulates to the brain. If CO2 levels are too high in the blood stream, the brain will shut down. Therefore, if you exhale, you are speeding up the whole process and increasing the risk of SWB quite drastically.
Never exhale forcefully upon surfacing.
• Exhaling forcefully and taking a huge gulp of air after a long and deep dive is not good policy, as there is a rapid increase of oxygenation. The brain receives the message that you have
enough or too much oxygen, therefore dropping the blood pressure. This sudden drop of partial pressure may trigger a BO.
Never dive or train when you are cold, tired, ill, under the influence of alcohol, drugs or medication.
• All these factors impair judgment, some quite radically and hence impairing breath holding abilities and predisposing an individual to BO.
Good Dive Practice
• Always dive within your limits.
• Depth is relative – for some divers 20m could be a deep dive and for others, a 40m could be a deep dive. Never feel pressured that you are underachieving. Dive to the depths that you
are comfortable at and increase depth slowly and allow enough time for adaptation.
• Listen to your body, it’ll tell you when you are going to overstay your welcome or when to call it a day.
• Don’t feel the need to out perform anyone in the group. It’s more than likely that they won’t even notice. The people you are diving with know your limitations and pushing the limits
drastically may make the group feel uncomfortable having you around because of the danger you are putting yourself. Plan your dive and dive your plan.
• Structure your training program or outings to suit you and everyone else participating in the event.
• Structure a Dive Plan and make sure all involved know it and stick to it.
• Layout an Emergency Plan and make sure all involved know what to do.
• Lay out a Contingency Plan and make sure all involved know of it.
• Review conditions on the day and activate the Contingency Plan if necessary or cancel the event if conditions are not favorable.
• Pay attention to details… don’t take anything for granted.
• Rig up all necessary equipment being used for a training session or outing, and double check everything prior activity.
• You should never dive alone, however, if you choose to do so, let someone know of your planned activity in detail
If you are training or diving alone.
• Train to a max 50% of your personal capability.
• If you’re diving alone, reduce dive rate and bottom time to about 50% of your personal capacity.
• Allow for longer recovery periods on the surface.
Maintain a good rest period between dives.
• Allow O2, CO2 and lactic acid levels to normalise.
• A good rule of thumb is to keep surface intervals at least double the time of the total dive.
• Allow longer surface intervals if you are diving deep or increased work rate intensity when submerged.
Don’t increase fining rhythm, especially in the last few meters.
• Economy of movement = conservation of O2 +maintaining low pulse rate.
Avoid large head movements up or down or extending your neck on ascent and descent.
• May cause diffi culty when equalising on descent.
• May affect blood fl ow to the brain on ascent.Increased pressure on the baro-receptors area of the neck can send the wrong message to the nervous system, which may increase pulse rate as well as bring on early diaphragm contractions.
• Rather use eye movement to observe where you are going.
Remove the snorkel from your mouth when diving.
• Clearing a snorkel on the surface when returning from a long dive could lead to complications such as a surface BO (sudden drop in partial pressures)
• Maintaining a snorkel in the mouth can create equalization problems for some divers.
Avoid rapid “turn arounds” at depth.
• This burns up precious oxygen and can send the wrong message to the nervous system, which may increase pulse rate as well as bringing on early diaphragm contractions. In extreme case (high
CO2 levels), this action could lead to a DWB.
• Before reaching the target depth/bottom, use your fins for drag to slow you down and position your body into a flaring position (like sky diving). This action can slow your descent quite radically.
Terminate the descent and pause for a moment before inverting to commence your ascent. Allow sufficient time for physiological adaptation.
• Pushing the envelope too far, too fast and too soon can be counter productive and dangerous. In some situations it is easy to become a victim of baro traumas as well as fall victim to BO’s.
Take your time warming up and focus on your deep breathing cycles and other breathing rhythms.
Allow at least 4 hours of digestion time before freediving after eating.
• You need as much oxygenated blood to feed the brain when in a state of apnea as possible, and not potions of oxygenated blood to be diverted to the digestive system to assist in the digestion of food.
Spearfishermen spend many hours exposed to the elements and often overlook or forget about the sun that is constantly beating down of them. Most of us tend to ignore this fact because we are in the water, and most of the time we feel rather comfortable with the temperature.You occasionally need to hydrate yourself and circulate cold water through your wetsuit jacket to cool your body
temperature down a little, especially if you wear an open cell wetsuit.
Enough fresh water is to be present at all training sessions or outings. Dehydration in freediving is caused mainly by: the mammalian dive reflex and during ventilation, where
a significant amount of water is expelled when breathing. The constant increase and decrease of pressure around the kidney area elevates the rate of urine produced.
All these factors cause you to lose body fluids rapidly. Dehydration increases the risk of black outs. Stay well hydrated.
Dehydration occurs when water volumes that are lost are greater than what is being replenished. Keep a water bottle nearby whenever you go freediving.
Some of the symptoms of mild dehydration
• Increase in heart rate
• Increase in body temperature
• Dry skin
• Dry mouth
• Muscle cramps
• Difficulty equalising
Course of action:
Hydrate the person as soon as possible with fluids containing electrolytes as found in sports drinks (sodium and potassium salts). If there is no immediate fluid which contains electrolytes, give the person quite a bit of water to drink until most symptoms have subsided and then introduce a small quantity of salty snacks or a very light meal.
Headache, pale, rapid and weak pulse, thirsty, weak, sweating, cramping.
Place the person in a cool and shady place and remove all excess clothing. Sponge off the body with cool water or submerge it in cool water. Provide small quantities of drinking water at a time for re-hydration.
Hot, flushed, dry skin, high body temp.
Place the person in a cool and shady place and remove all excess clothing. Sponge off the body with cool water or submerge it in cool water and alert emergency services. Hydrate and monitor the victim closely until help arrives. If the victim stops breathing, feel for a pulse and administer mouth to mouth resuscitation and continue until the victim is breathing on their own. If the heart
stops, commence CPR immediately.
Post Diving Fatigue
This is often referred to as “snorkelites” and occurs when you feel exhausted after the day’s diving and just want to sleep. The reason for this is a combination of effects that your body goes through, which is triggered by the MDR and depletes your body’s natural salts and fluids, causing fatigue.
Course of action
Rehydrate well with electrolyte-enriched fl uids in order to elevate the minerals and natural body salt count. Have a good meal, take a power nap and you’ll feel on top of the world when you wake up.
Make sure that you have personal details with you, and keep them all together in a safe place. Make sure that your dive buddies know where all the relevant documents are and that you have your buddy’s details as well.
• ID Book
• Full name and address
• Next of kin details
• Alternative phone no. and details
• Medical aid details
• DAN details if applicable
• Allergies if any
An area often over looked in diver safety is dive gear management. It’s important to maintain your gear and to always check for evidence of damage on ageing or frequently used equipment.
After every outing, one should rinse their gear off in fresh water. Use a non-ammoniac soapy liquid such as dish washing liquid on plastic and silicone surfaces to get rid of chlorine or saline traces, as well as to control fungal growth. Rinse equipment off in fresh water and dry gear well as humid equipment in a closed environment can promote fungal growth. Check all equipment for wear
and tear, and then service or replace it if necessary. Apply silicone lubricant to rubber and plastic gear. Not only does this hydrate the materials, but it also keeps your gear looking as good as new.
Neoprene gear should also get its fair share of maintenance. Wash it in anti-bacterial neoprene shampoo at least once a month and, every so often, wash it in fabric softener as well. This keeps the nylon cladding supple and always smelling fresh. Look for tears and patch/glue surfaces together with special neoprene contacted adhesive glue. If the stitching is coming loose, cut away any lose threads and knot the ends to prevent any further runs. If mending requires special attention, rather take your wetsuit to a reputable place which specialises in neoprene mending. Over a
period of time, the nylon cladding may develop little nylon balls from wear and tear. Use a lighter in a sliding action over the affected area, to burn all the nylon balls away. Alternatively, you can shave the them off with a razor.
Have boxes or containers where equipment is packed, as it prevents damage during storage. Purchase a good quality wetsuit hanger, as these are designed especially for wetsuits, and are constructed with large radius bends. This avoids stretching and damaging the neoprene at the shoulder area leaving it with points and creases, and avoids causing weaknesses in the material.
Try to avoid drying gear in direct sunlight, as UV-rays on dive gear damage the integrity of the materials. Hang your gear up in a well ventilated and shaded area and allow it to dry there. On the odd occasion, turn your wetsuit inside out and expose it to direct sunlight for 20 minutes or so, as this kills off bacteria and fungal growth inside the wetsuit.
SAFER DIVING GUYS!
For A breakdown of Freediving Terms please see: