Freediving safety

Safety proceedures in freediving

Performance freediving is a dangerous leisure activity. The consequence of small misstakes can be fatal, both at competition, training and especially by those that has not yet taken a course in freediving. The main danger is to suffer lack of oxygen - which will cause loss of motor control and in extension also a blackout. Both these will probably occur at the surface. But if hyperventilating before a dive or extending your dive beyond your limits you might suffer shallow water blackout. Which could be explained in a decrease in waterpressure while descending the last meters which will cause oxygen leaving your blood and your brain and reentering the lungs - you blackout - lose your air - sink - and die.

Here are a summary of the basic safety rules:

1	Do not push your limits without proper education.
2	Dive under direct observation of your dive buddy. Tell him/her what you plan to do.
3	Do not hyperventilate (no deeper/faster breathing). It can lead to black out without warning. 2-3 slow deep breaths is enough as preparation.
4	Do not go deeper if you feel pressure on your eardrums. Equalize all the time. Accept no discomfort.
5	If problems - drop your weights.
6	Do not exhale, or stop on the way up (it enhances the risk of Shallow Water Blackout). Swim straight up.
7	Your lowest level of oxygen is 20 seconds after surfacing. Keep breathing (or observing the freediver).
8	Rest without moving between dives. Rest twice the duration of your last dive.
9	Secondary drowning (death) may occur up to 24 hours after small amounts of water has entered your lungs.
10	Use a dive line to a secure buoy if you plan to push yourself. Stick to the dive line. NEVER ever swim passed the bottom weight!
11	Do not take air from scuba bottles. Do not freedive after scuba diving, rest more than 12 hours.
12	Drink lots of water before a freediving session. Do not be hungry, or too full.
13	Do not dive deep when you are cold. Don’t dive with fever, infections or drugs in your body e t c
14	Evaluate the dive site. Know about currents and good exit points. Do not touch reef or animals (they or you might get harmed).
15	Relax, Enjoy and listen to your body.

Below is a more detailed descriptions on how to increase safety when freediving.

1	Do not push your limits without proper education. Freediving is much more complicated than scuba diving. The fact that your body and mind decides your limits means that YOU are involved to a higher degree and have to have more experience and knowledge. A short course will teach you how to perform in a safe way.
2	Dive under direct observation of your dive buddy. Tell him/her what you plan to do. This is the main rule. People break it and die. Divers have died while doing quite routine and simple performances while being alone (or in pools beside people that do not understand freediving). Direct observation means that someone is observing you from a few meters away. On the pools edge or at the surface observing you (specially when you come up). Dive buddy means someone that actually understands freediving (SWB and BTT). You have to inform your dive buddy, otherwise he/she will not be attentive and alert.
3	Do not hyperventilate (no deeper/faster breathing). It can lead to black out without warning. 2-3 slow deep breaths is enough as preparation. This rule has been broken by people that are not alive any more. Any added breathing above the body´s normal breathing will lower the carbon dioxide levels in the blood and the urge to breath might come after you have fainted because of low oxygen.
4	Do not go deeper if you feel pressure on your eardrums. Equalize all the time. Accept no discomfort. Beginners think they shall equalize when they feel pressure. That is wrong. Profesionals never feel the waters pressure on the eardrums - they equalize all the time.
5	If problems - drop your weights. Not many do, they rather take the risk, or are already too gone in the head due to low O2, so it does not occur to them that they can drop the weightbelt and get an easy ride to the surface. There is away around this. Release the belt and hold it in your hand, if you suffer SWB you will drop the weights and insetad of losing all air from lungs and sinking you might actually float up instead, if the weights are gone. Weight yourself positive at 10 meters, at least.
6	Do not exhale, or stop on the way up (it enhances the risk of Shallow Water Blackout). Swim straight up. At the end of the dive and when the pressure decreasses the risk of shallow water blackout increases every second. Do not stay in the risk zone go direct up and breath. Preferably hook breath.
7	Your lowest level of oxygen is 20 seconds after surfacing. Keep breathing (or observing the freediver). Focus on inhaling when you break the surface, only a litre of new air is enough to oxygenate the brain and keep you conscious. The professionals release some air right before the surface and inhale directly when breaking the surface. They hook breath: inhale and hold and crunch with the stomach for a second before taking another breath and another hook breath. This increases blood pressure and even oxygen pressure in the lung.
8	Rest without moving between dives. Rest twice the duration of your last dive. It takes only a few breaths to oxygenate the blood that leaves the lung and the heart (artreila oxygen saturation 99-100%), but the blood in the venous return (normally 80% saturation) coming back from the tired muscles will stay low on oxygen for several minutes. This you can not feel. If you would start a new dive before these values have returned to normal, this new dive will be much more dangerous than the first one.
9	Secondary drowning (death) may occur up to 24 hours after small amounts of water has entered your lungs. Water in your lungs will damage the lungs ability for gas exchange. This means less oxygen will enter your blood and you might faint and suffocate. First signs and symptoms consits of agitated breath (even if resting), coughing, headache and more. It is enough with just small amount such as 2-3 deciliters. Death can occur many hours after you stopped diving. You must be taken to hopsital for O2 treatment and surveillance.
10	Use a dive line to a secure buoy if you plan to push yourself. Stick to the dive line. NEVER ever swim passed the bottom weight! This is especially important in low visibility. Things can go wrong in a dive. Damage to eardrums may cause vertigo and you may lose your sense of direction. Cramp may inhibite your ability to swim up. Lots of things can go wrong.
11	Do not take air from scuba bottles. Air expands on the way to the surface. If you take a breath at 10 meters, this air will double in volume towards the surface. Yur lungs can get damaged. Do not freedive after scuba diving, rest more than 12 hours. Scuba diving involves a lot of compressed air being breathed. Excessive levels of compressed nitrogen will be stored in your blood. This nitrogen takes several hours of breathing on land to get rid of. If you start freediving you will recompress this nitrogen and nitrogen bubbles may end up in your brain. You might die.
12	Drink lots of water before a freediving session. Just 1% of dehydration will affect your perfomance 10%. Dehydration will affect your ability to act and think clearly. Swimming in water will trigger an urge to pee. You lose water. When swimming in water you do not feel if you are sweating- you lose water. You loose lots of water while diving. It takes several hours to store water (or re hydrate). Your body can only absorb 2.5 decilitres an hour. Start drinking water the night before your dive session. Do not be hungry, or too full. If you have eaten too much and jump in the water, lots of energy (oxygene) is used to digest your food. Do not push your limits if to full. If you are hungry you will freeze more easily. If you run out of carbohydrates you will start metabolixing your fat stores - this costs more oxygen (about 6% more).
13	Do not dive deep when you are cold. Don’t dive with fever, infections or drugs in your body e t c Feelings of euphoria and agitation may be felt when diving and being in water. This may hide any signs of your illness, but it is still there, having an adverse effect on your body, limiting your capabilities.
14	Evaluate the dive site. Know about currents and good exit points. It is easy to get in if jumping, gettig out of a rocky or reefy shore is complicated even in the slightest of waves. Tides and currents may sweep you out at sea. It happens, and people die. Do not touch reef or animals (they or you might get harmed). Animals and plants have intricate ways of protecting themselves some of them poisonious. If touching reef or fish you damage a tiny invisible layer that protects them from diseases. Manhandling marine life may cause it to die later on. You are a vistor in someone elses home.
15	Relax, Enjoy and listen to your body. Do not dive against the depth gauge - listen to your body instead.

SELFRESCUE - if in doubt of making it to surface

- Relax even more, but open your eyes and your consiousness and remind yourself on your upcoming breathing routine.

- Use the line to pull yourself up - using new musclegroups closer to the bloodcirculation.

- Loosen belt, holding it in one hand. At blackout you will drop belt and your level of positive bouyancy will be deeper! (Note: If losing your air - your will probably turn negative in bouyancy directly, if not dropping your weights)

RIGHT: Do not do anything but breath upon return - focus on breathing in - keeping your lungs under pressure.

THE COMPANION

1) Meet partner halfway (or the last 10 meters depending on visibility and the depth of the dive) - but always within your own limits - it is better to wait at five meters being strong and fresh in case your assistance is needed in the "shallow water blackout area". Hold and feel the line - look down.

2) Be within reach - at armslength distance.

3) Mistrust any OK signs from buddy - observe until he talks or breathing is somewhat normal.

Take visibility into account.

RESCUE - ACTION

If partners breathing is irregular, or his gaze is blank. Support him keeping his airways out of water. If suffering LMC - stop diving for the day.

BLACKOUT OR SEVERE LOSS OF MOTOR CONTROL.

1) Turn partner unto his back (check grips below).
2) Urge him to breath (he can hear you even during blackout).
3) Pat his cheek gently.
4) If breathing does not start - Lift mask to forehead and blow over face.
5) If breathing does not start - Blow more.
6) If breathing does not start BLOW MORE over face.
7) after some 20-30 secs without breathing start with one "CPR blow", which might open up a cramping epiglottis.
6) If breathing does not start - drop belts - get victim to safe ground - start CPR.
If any water in lungs ALWAYS seek hospital - drowning can occur hours after resurfacing.

RECOVER A FREEDIVER FROM DEPTH

If your partner stops swimming.

- Preferably hold at the back of the head and under jaw (closing the mouth) - or - support him under armpit or elbow or grab his wrist over his head. Pull him to surface. Drop belts if needed.

- If partner stops swimming and loses air it is always a good idea to close his airways while transporting him to the surface. Check grip above.