Source: Is Scuba Diving Safe?
Scuba diving is an activity that allows you to get to know the underwater world. It allows you to experience the underwater landscape (fish, turtles, caves, plants, coral reefs, etc.). It is important to know the techniques to adopt and the mistakes to avoid in order to do so. All these measures make it possible to practice this discipline in complete safety.
It is certainly exciting, but involves high risks, which is why it is recommended to consult a doctor before any practice (contraindication in case of cardiovascular disease, asthma, etc.).
Risks of decompression and barotrauma
All divers can be victims of diving accidents, whether they are professionals or amateurs. Diving is not an activity that is suitable for everyone, that is why training and consultation with a doctor is necessary beforehand.
Source: How Dangerous is Scuba Diving
The risks of decompression (desaturation) are no less important, such as decompression sickness (pressure exerted on the body when it is subjected to a pressure higher than that which it undergoes on land). During diving, the nitrogen concentration in the body increases with depth and duration, which will dissolve in the blood. The diver must respect certain steps to evacuate this chemical entity, including degassing. When the duration of the stops and the number of stops are not respected, the diver risks a decompression accident and serious injuries, because the nitrogen in the blood does not have time to reach the lungs. It is therefore recommended not to fly within 24 hours of the dive, unless the dive lasted only 2 hours, then he can fly within 12 hours.
To avoid this risk, it is important to respect the number of stops and the ascent rate (15 to 18 m/minute). You should also not smoke 8 to 12 hours before diving and limit your alcohol consumption during your diving stay.
Other accidents can also occur, such as barotrauma (lung, dental, sinus and ear).
Sinus barotrauma is the difference in pressure between the external pressure and the nasal cavity. In this case, the diver feels pain in the forehead and bleeds from the nose. It is recommended to avoid diving with a cold, rinsing the nose with sea water may also be a solution.
Ear barotrauma is a deformation of the eardrum due to the pressure induced by depth. It appears on both the descent and ascent, and the diver may experience severe ear pain, which can cause him to faint if there is no internal rebalancing.
To avoid this problem, the diver can pinch his nose and simply blow or yawn. You should not continue the descent if it persists, you just have to go back up and try again, but if it happens during the ascent, you have to go down a few meters and make jaw movements.
Pulmonary barotrauma or pulmonary suppression is due to the variation in air volume, which is due to the change in pressure. It occurs in the first 10 metres after the surface.
The diver must therefore exhale more than inhale, especially during the ascent, because when it is too fast, the gas expands and also dilates the lungs to the yield point of the alveoli and causes them to crack, that of the bronchi, pleura and gas emboli. He will then feel violent pain in his chest accompanied by spitting blood.
The diver should be put on oxygen and called for help in the event of such a trauma. You must also listen to the instructor and respect the “always above and below” rule, i.e. do not apnea while scuba diving or insist on exhaling on the way up, which can lead to loss of consciousness and drowning.
Dental barotrauma is related to poorly maintained tooth carries and hollow dressings, which create air pockets in the teeth.
Teeth must therefore be healthy to avoid this disorder and an annual visit to the dentist is required to highlight his activity to the practitioner, so as to make a waterproof filling.
Chemical and Biological Incidents
The risk of biochemical incidents is frequent, including narcosis (or deep drunkenness). It is characterized by a diver’s euphoria until he loses his thinking skills and forgets about safety rules. It is due to the increase in nitrogen level and pressure change occurring at depths of 30m and above, scouring at depths of 60m and loss of consciousness at depths of 90m and above. Everything depends on the depth, physical condition and condition of the diver, such as a sudden and too fast ascent of the diver.
You have to go up to the surface to lower your blood pressure or go down by slowing down from 30m to avoid this evil. Perform a rehabilitation dive if you have not dived for some time. The use of gases, such as Nitrox or Trimix, is also a solution, as they reduce nitrogen pressure to reduce the risk of narcosis.
This disorder is caused by a poor lifestyle, so it is better not to consume alcohol before an underwater immersion and avoid taking certain medications.
Intoxication and Hypercapnia
Oxygen and carbon monoxide poisoning is due to improper inflation of the cylinders, as they contain too much oxygen or monoxide, causing headaches, sweating and nausea. Smoking should be avoided 8 to 12 hours before diving, as tobacco contains carbon monoxide and promotes this type of incident. The rules for inflating cylinders must also be strictly observed.
Shortness of breath or hypercapnia is characterized by an excess of external carbon dioxide (pollution, dead space of the snorkel, etc.) or internal carbon dioxide (physical effort, bad exhalation during diving, cold temperature, etc.). Symptoms are felt depending on the pressure (it may be a slight shortness of breath, headache, suffocation, syncope or death in the worst case).
If the dive is running out of breath, wave to other divers or stop exercising and catch your breath. Increasing the duration of the bearings is also recommended. If the symptoms do not disappear, it is preferable to gently surface with the help of the partner.
Other Possible Concerns
The risks of physical weakness are just as regular, such as back problems, because the weight of the diving equipment is not less and can lead in some cases to a lumbar disc hernia. It is sometimes recommended to get your equipment in the water and follow the doctor’s advice in case of back pain.
Hypothermia is characterized by a drop in body temperature below normal. It occurs when the diver does not equip himself with the appropriate suit. It can lead to a serious diving accident.
It is therefore essential to protect yourself well and wear a suit adapted to the type of diving, to also wear a thick hood, because a diver loses 80% of body heat through the head.
Different types of accidents are recorded during diving, such as environmental accidents (drownings, cold, fauna, flora, etc.) and hyperbaric accidents (pressure and volume variations, toxic accidents, decompression, etc.).
Pulmonary edema is related to hydrostatic hyperpressure due to immersion, over-tightening, stress and resistance of the regulator. It can lead to heart disease or silent high blood pressure.
It is therefore important to avoid cold water efforts, rapid ascents, tight suits and poorly adjusted or overly hard regulators.
The plating of the mask is a diving accident, which is due to a decrease in the air under the mask, which creates a suction cup effect that sucks in the skin, nose and eyes. Conjunctival bleeding, epistaxis and purpuric spots are the consequences of this disorder.
It is thus necessary to blow into the mask by going down through the nose, until the pressures are balanced to avoid these traumas.
Digestive damage is a disease caused by intestinal gases, which dilate as the diver ascends.
It is recommended to take soft drinks or starchy foods before diving at the risk of other biochemical disorders, such as hypoxia (occurs only in apnea) and hyperoxia (occurs when oxygen blood pressure above 1.6 bar is breathed pure or with hyperoxygen mixtures).
Multiple accidents can occur if immersion is not properly practiced, such as alternobaric vertigo, high pressure nervous syndrome (HPSS), cuts, sores or other injuries caused by the penetration of wrecks or animals (jellyfish, sharks, moray eels, rays, corals, etc.).
Diving Safety Rules
Source: 5 Rules Of Scuba Diving
Safety rules are established to allow divers to practice safely.
It is important to start your descent properly, as it increases the ambient pressure and the only way to restore it is to perform the Valsalva manoeuvre, which consists of blowing while holding your nose pinched and your mouth closed.
The ascent is just as important. It is done using Toynbee’s Maneuver of pinching his nose, but this time swallowing. It is also essential to respect the decompression stops established according to the duration of the dive and the depth reached.
The first step before diving is to have a medical check-up beforehand. It is important to respect the doctor’s advice and instructions, as certain diseases or disabilities can have serious consequences in an underwater environment. A medical certificate is therefore essential before any practice.
You must also be over 8 years old to be able to go under the sea. Pregnant women are prohibited from practicing.
It is essential never to dive alone, this activity is always done in pairs to reduce risks.
A postponement of the dive is not prohibited, so if a sensation, however subjective, bothers the diver, it is better to postpone. Prevention is better than cure, as the saying goes.
A first dive is practiced from the age of 8 years and lasts between 20 and 40 minutes on a surface between 3 and 6 m deep under the supervision of an instructor. It is essential to start scuba diving, reinforced by theoretical training. This makes it possible to practice safely by learning the signs between divers, regulating air pressure in the ears, breathing, etc.
Another advice is to respect the decompression stops, because the nitrogen breathed through the air cylinders is subject to underwater pressure. The longer the diver remains underwater, the more necessary it is to respect the bearings during the ascent.
For a Safe Dive – Follow These Important Tips
- Do not dive after a heavy or over-watered meal
- Not to be sober on an empty stomach
- Do not dive without a scuba wetsuit as it acts as a thermal insulator and protects against underwater fauna and flora
- Do not snorkel after diving
- Do not make unnecessary efforts before, during and after diving
- Take the time to acclimatize to the aquatic environment
- Limit depths, dive times and stay within the safety curve
- Always go up slowly
- Comply with the decompression stops to the letter with a safety stop (3min by 5m)