thumb
Diver rescue, following an accident, is the process of avoiding or limiting further exposure to
diving hazardsDivers face specific physical and health risks when they go underwater or use high pressure breathing gases. Some of these conditions also affect people who work in raised pressure environments out of water, e.g...
and bringing a
SCUBA diverScuba diving is a form of underwater diving in which a diver uses a scuba set to breathe underwater for recreation, commercial or industrial reasons.Unlike early diving, which relied exclusively on air pumped from the surface, scuba...
to safety. A safe place is often a place where the diver cannot drown, such as a
boatA dive boat is a boat that scuba divers use to reach a diving site which they could not reach by swimming from land.-Dive boat features:Features that make a boat suitable for use by divers are etait super con* marine VHF radio* oxygen first aid...
or the shore, from which professional medical treatment can be sought.
Reasons for needing rescue
There are many reasons that divers need rescue, including:
- running out of breathing gas
Breathing gas is a mixture of gaseous chemical elements and compounds used for respiration.Air is the most common and only natural breathing gas...
- unconsciousness
Unconsciousness, more appropriately referred to as loss of consciousness or lack of consciousness, is a dramatic alteration of mental state that involves complete or near-complete lack of responsiveness to people and other environmental stimuli. Being in a comatose state or coma is an illustration...
- being unable to see the depth gauge
A depth gauge is a pressure gauge that displays the equivalent depth in water. It is a piece of diving equipment often used by SCUBA divers.Most modern diving depth gauges' have an electronic mechanism and digital display. Older types used a mechanical mechanism and analogue display.A diver uses a...
or diving computer to make a safe ascent, generally because the diving maskA diving mask is an item of diving equipment that allows scuba divers, free-divers, and snorkelers to see clearly underwater. When the human eye is in direct contact with water as opposed to air, its normal environment, light entering the eye is refracted by a different angle and the eye is unable...
is lost, keeps flooding or is damaged
- panic
Panic is a sudden fear which dominates or replaces thinking and often affects groups of people or animals. Panics typically occur in disaster situations, or violent situations which may endanger the overall health of the affected group...
- trauma
Physical trauma refers to a physical injury, generally of a considerably severe degree. A trauma patient is someone who has suffered serious and life-threatening physical injury with the potential for secondary complications such as shock, respiratory failure and death.-Common causes:Comprehensive...
, diving disorderDivers face specific physical and health risks when they go underwater or use high pressure breathing gases. Some of these conditions also affect people who work in raised pressure environments out of water, e.g...
, medical condition
- becoming lost or trapped underwater
Underwater is a term describing the realm below the surface of water where the water exists in a natural feature such as an ocean, sea, lake, pond, or river. Three quarters of the planet Earth is covered by water. A majority of the planet's solid surface is abyssal plain, at depths between 4000...
- being unable to return to the shore or a boat after a dive
Rescuers and training
In
recreational divingRecreational diving or sport diving is a type of diving that uses SCUBA equipment for the purpose of leisure and enjoyment. In some diving circles, the term "recreational diving" is used in contradistinction to "technical diving", a more demanding aspect of the sport which requires greater levels...
, the urgency of the rescue and the remoteness of dive sites mean that professional rescuers rarely take part in diver rescues. Other divers at the scene become rescuers.
As the immediate in-water rescuer is often the diver's own
buddyThe buddy system is a procedure in which two people, the buddies, operate together as a single unit so that they are able to monitor and help each other. In adventurous or dangerous activities, where the buddies are often equals, the main benefit of the system is improved safety: each may be able...
,
diver training agencies often teach rescue techniques in intermediate-level
diver trainingDiver training is the process of developing skills and building experience in the use of diving equipment and techniques so that the diver is able to dive safely and have fun....
courses; examples are the
PADIPadi or PADI can refer to:* Professional Association of Diving Instructors, diver training organization* Paddy field * Padi, Chennai, satellite township of Chennai, India* Padi , Indonesian band...
Rescue Diver, the
BSACBSAC can stand for:*Berkeley Sensor and Actuator Center*Bit Sliced Arithmetic Coding, audio coding from MPEG-4 Part 3*British South Africa Company*British Sub-Aqua Club*British Society for Antimicrobial Chemotherapy*Black Swamp Area Council...
Sport Diver and the DIRrebreather Rescue courses.
When the rescue involves a group of people, co-ordination is needed to make it quick and effective. This may be carried out by the
skipperSkipper may refer to:* Skipper , a person who has command of a vessel* Skipper , a butterfly of the family Hesperiidae, and superfamily Hesperioidea* Skippers Seafood & Chowder House, an American chain of seafood restaurants...
of the boat, if diving is taking place from a boat, or by a diver. Some training agencies offer courses to prepare divers for such as role, for example BSAC's Practical Rescue Management course.
Rescue activities
The effort and difficulty of a rescue varies widely and depends on many factors such as the nature of the problem, the underwater conditions and the type and depth of the dive site. A simple rescue could be to tow to safety a diver on the surface who is exhausted or suffering from leg
crampFor the heraldic device, see cramp ; for the band, see The CrampsCramps are unpleasant, often painful sensations caused by contraction or over-shortening of muscles...
s. A complex and high-risk rescue would be to locate, free and bring to the surface a lost diver who is trapped
underwaterUnderwater is a term describing the realm below the surface of water where the water exists in a natural feature such as an ocean, sea, lake, pond, or river. Three quarters of the planet Earth is covered by water. A majority of the planet's solid surface is abyssal plain, at depths between 4000...
in an enclosed space such as a
shipwreckA shipwreck is the remains of a ship that has wrecked, it having either been sunk or beached. A shipwreck can refer to a wrecked ship or to the event that caused the wreck, such as the striking of something that causes the ship to sink, the stranding of the ship on rocks, land or shoal, or the...
or
caveCave diving is a type of technical diving in which specialized SCUBA equipment is used to enable the exploration of natural or artificial caves which are at least partially filled with water...
with limited
breathing gasBreathing gas is a mixture of gaseous chemical elements and compounds used for respiration.Air is the most common and only natural breathing gas...
supplies.
The sequence of potential activities needed in a generic rescue are:
- if the casualty's position underwater in unknown, locate the casualty and, if possible, mark the position
- if the casualty is trapped, free the casualty
- if the casualty is low on breathing gas
Breathing gas is a mixture of gaseous chemical elements and compounds used for respiration.Air is the most common and only natural breathing gas...
, provide more gas
- if the casualty is submerged, bring the casualty to the surface
- if the casualty is not buoyant at the surface, make the casualty buoyant
- if the casualty is not breathing, carry out continuous artificial respiration
Artificial respiration is the act of simulating respiration, which provides for the overall exchange of gases in the body by pulmonary ventilation, external respiration and internal respiration...
on the surface
- if help at the surface is available but not at hand, attract help
- if the casualty is on the surface in the water and no help is available, tow the casualty to a boat or to land
- if the casualty is beside a boat or the shore, remove the casualty from the water
- if necessary, resuscitate, provide first aid and arrange transport to professional medical help
Locating the casualty underwater
It may be difficult to locate the diver
underwaterUnderwater is a term describing the realm below the surface of water where the water exists in a natural feature such as an ocean, sea, lake, pond, or river. Three quarters of the planet Earth is covered by water. A majority of the planet's solid surface is abyssal plain, at depths between 4000...
where dives take place in low visibility conditions, in currents or in enclosed spaces such as
caveA cave or cavern is a natural underground void large enough for a human to enter. Some people suggest that the term cave should only apply to cavities that have some part that does not receive daylight; however, in popular usage, the term includes smaller spaces like sea caves, rock shelters, and...
s and
shipwreckA shipwreck is the remains of a ship that has wrecked, it having either been sunk or beached. A shipwreck can refer to a wrecked ship or to the event that caused the wreck, such as the striking of something that causes the ship to sink, the stranding of the ship on rocks, land or shoal, or the...
s or where the diver uses breathing equipment which releases few bubbles, such as a
rebreatherA rebreather is a type of breathing set that provides a breathing gas containing oxygen and recycled exhaled gas. This recycling reduces the volume of breathing gas used, making a rebreather lighter and more compact than an open-circuit breathing set for the same duration in environments where...
.
Diver often use
distance lineA distance line, penetration line or guideline is an item of diving equipment used by SCUBA divers as a means of returning to a safe starting point in conditions of low visibility, water currents or where pilotage is difficult...
s,
surface marker buoyA Surface Marker Buoy, SMB or simply a blob is an inflatable buoy used by SCUBA divers, with a line, to mark the diver's position to their surface, safety boat while the diver is underwater.- Surface Marker Buoy :...
s,
diving shotthumb|right|Diagram of a diving shot upcurrent of a dive siteA diving shot is an item of diving equipment consisting of a weight, a line and a buoy. The weight is dropped on the dive site. The line connects the weight and the buoy and is used by divers to move between the surface and the dive site...
s,
lightstickA glow stick is a single-use translucent plastic tube containing isolated substances which when combined make light through a chemical reaction-induced chemiluminescence which does not require an electrical power source. Millions of glow sticks are sold annually.- History :Cyalume was invented by...
s and
strobe lightStrobe light or stroboscopic lamp, commonly called a strobe, is a device used to produce regular flashes of light. It is one of a number of devices that can be used as a stroboscope...
s to indicate their position to their surface support team. A standard precaution when entering enclosed spaces is to use a distance line; this marks the exit route, which may be need after the diver's fins and bubbles dislodge
siltSilt is soil or rock derived granular material of a grain size between sand and clay. Silt may occur as a soil or as suspended sediment in a surface water body...
and loose overhead materials such as
rustRust is a general term for a series of iron oxides, usually red oxides, formed by the reaction of iron and oxygen in the presence of water or air moisture. Several forms of rust are distinguishable visually and by spectroscopy, and form under different circumstances...
and reduce visibility to zero.
Common search techniques such as the
circular searchAn underwater circular search is a search and rescue strategy conducted by a diver swimming around a fixed pivot point. In some cases a second diver can anchor himself to the bottom and act as both the pivot point and line tender. The diver and line tender communicate with each other using line...
or
jackstay searchAn underwater jackstay search is a search and rescue strategy conducted by two divers swimming along a fixed search line.There are two techniques for performing a jackstay search....
, need preparation and practise if they are to be used effectively and safely.
Searches of enclosed spaces expose the rescuer to danger. The rescuers may need training and experience in
Cave divingCave diving is a type of technical diving in which specialized SCUBA equipment is used to enable the exploration of natural or artificial caves which are at least partially filled with water...
to minimise the risks of that type of rescuer.
Freeing the trapped casualty
Divers may become trapped in
fishing netA fishing net or fishnet is a net that is used for fishing. Fishing nets are meshes usually formed by knotting a relatively thin thread. Modern nets are usually made of artificial polyamides like nylon, although nets of organic polyamides such as wool or silk thread were common until recently and...
s;
monofilamentA monofilament may be:* Monofilament fishing line, a type of thread* Monomolecular wire, a fictional type of wire consisting of a single strand of moleculesSee also: filament...
is almost invisible underwater.
RopeA rope is a length of fibers, twisted or braided together to improve strength for pulling and connecting. It has tensile strength but is too flexible to provide compressive strength...
s also are a threat to the diver's safety; normal
diving equipmentThe fundamental item of diving equipment used by divers is the SCUBA equipment, such as the Aqualung or Rebreather. There are other important pieces of equipment that make diving safer, more convenient or more efficient.-Scuba life support:...
has many inaccessible snag points that can trap the diver. Another problem occurs when divers try to squeeze through small gaps where their bulky equipment become wedged or caught. Also, old
ferrousFerrous, in chemical science, indicates a bivalent iron compound , as opposed to ferric, which indicates a trivalent iron compound ....
shipwrecks can be structurally unstable; they often retain their shape and therefore have components or cargos that have high
potential energyPotential energy is energy stored within a physical system as a result of the position or configuration of the different parts of that system. It is called potential energy because it has the potential to be converted into other forms of energy, such as kinetic energy, and to do work in the process...
due to gravity, but which have lost their strength through
corrosionCorrosion is the disintegration of a material into its constituent atoms due to chemical reactions with its surroundings. In the most common use of the word, this means a loss of electrons of metals reacting with water and oxygen. Weakening of iron due to oxidation of the iron atoms is a...
.
Divers routinely carry a
knifeA knife is any cutting edge or blade, handheld or otherwise, with or without a handle. Knives were used at least two-and-a-half million years ago, as evidenced by the Oldowan tools. Originally made of rock, flint, and obsidian; knives have evolved in construction as technology has with blades...
, line cutter or
scissorsScissors are hand-operated cutting instruments. They consist of a pair of metal blades connected in such a way that the sharpened edges slide against each other. Scissors are used for cutting various thin materials, such as paper, cardboard, metal foil, thin plastic, cloth, rope and wire...
or shears to free themselves from ropes, lines and nets.
Lifting bagA lifting bag is an item of diving equipment consisting of a robust and air-tight bag with strops, which is used to lift heavy objects underwater by means of the bag's buoyancy...
s can be used to help move heavy objects underwater.
Providing emergency gas
Running out of gas is a major cause for diving accidents.
The main reasons for running out of gas are:
- failing to monitor consumption of the gas - not watching the contents pressure gauge
- under-estimating the amount of gas needed for the ascent and decompression stop
A decompression stop is a period of time a diver must spend at a constant depth in shallow water at the end of a dive to safely eliminate absorbed inert gases from the diver's body to avoid decompression sickness...
s
- consuming gas faster than estimated by going too deep, over-exercising or psychological stress
- equipment failure, such as a frozen first stage or blown o-ring, in the main breathing set leading to escape of gas
Even when the prime cause of an underwater emergency is not running out of gas, lack of gas can easily become another problem for the rescuers to overcome because more gas is consumed during the accident and its aftermath. This is could be due to the diver remaining at depth for longer than planned or due to increases in the diver's breathing rate, due to exercising or
panicPanic is a sudden fear which dominates or replaces thinking and often affects groups of people or animals. Panics typically occur in disaster situations, or violent situations which may endanger the overall health of the affected group...
.
Common configurations of diving cylinders and diving regulators used for as a backup or reserve for emergencies include:
- an independent set - a complete, backup set such as a "pony" or one half of a “twinset” worn by a diver or a separate set brought down by the rescuer
- an "octopus" - a second, backup demand valve or mouthpiece
In breathing sets, a mouthpiece is a part that the user grips in his mouth, to make a watertight seal between the breathing set and his mouth. It is composed of a short flattened-oval tube that goes in between the lips, with on its free end a flange that fits between the lips and the tooth and gums...
on a scuba set that is already being used by the diver
- a "spare air" - a small independent set with integrated regulator and mouthpiece
See the
diving cylinderA diving cylinder, scuba tank or diving tank is used to store and transport high pressure breathing gas as a component of SCUBA . It provides gas to the SCUBA diver through the demand valve of a diving regulator.Diving cylinders typically have an internal volume of between and a maximum pressure...
and
diving regulatorA diving regulator is a pressure regulator used in a scuba set that supplies the diver with breathing gas at ambient pressure from one or more diving cylinders. The gas may be air or one of a variety of specially blended breathing gases...
articles for more details of the configurations.
There are two main ways of delivering the gas to the out-of-air diver; provide the casualty with a normal demand valve, preferably on a long hose, or "buddy breathing", the more risky of the two, where the two divers share one mouthpiece.
The gas capacity of the cylinder is important. Divers breathing at depth consume more gas because the gas must be delivered to them at ambient pressure. At the end of a deep dive they will need gas to breathe during the slow ascent to the surface and during any
decompression stopA decompression stop is a period of time a diver must spend at a constant depth in shallow water at the end of a dive to safely eliminate absorbed inert gases from the diver's body to avoid decompression sickness...
s.
The mixture of the
breathing gasBreathing gas is a mixture of gaseous chemical elements and compounds used for respiration.Air is the most common and only natural breathing gas...
is important. Hyperoxic gases cannot be breathed safely below their
maximum operating depthIn technical diving, the maximum operating depth of a breathing gas is the depth at which the partial pressure of oxygen of the gas mix exceeds a safe limit...
because of the risk of
oxygen toxicityOxygen toxicity is a condition resulting from the harmful effects of breathing molecular oxygen at elevated partial pressures. It is also known as oxygen toxicity syndrome, oxygen intoxication, and oxygen poisoning...
and hypoxic gas cannot be breathed safely in shallow water because the
partial pressureIn a mixture of ideal gases, each gas has a partial pressure which is the pressure which the gas would have if it alone occupied the volume. The total pressure of a gas mixture is the sum of the partial pressures of each individual gas in the mixture....
of
oxygenOxygen Oxygen Oxygen (acid, literally "sharp", from the taste of acids) and -γενής (-genēs) (producer, literally begetter) is the element with atomic number 8 and represented by the symbol O...
falls below that needed to sustain
consciousnessConsciousness is subjective experience or awareness or wakefulness or the executive control system of the mind. It is an umbrella term that may refer to a variety of mental phenomena...
.
Bringing the casualty to the surface
If one of the divers is out of gas and is breathing gas from the rescuer, the rescuer and casualty must remain close to one another and ascend together. This ascent is complicated by the casualty's lack of gas to become buoyant at the start of the ascent and at the surface. At the start of the ascent the casualty needs to fin upwards and keep pace with the rescuer until, with the drop in ambient pressure, the gas inside buoyancy devices such as the buoyancy compensator or
diving suitA diving suit is a garment or device designed to protect a diver from the underwater environment. Modern diving suits can be divided into two kinds:* "soft" or ambient pressure diving suits - examples are wetsuits, dry suits, semi-dry suits and dive skins...
, expands and provides buoyancy.
If the casualty is not capable of making an ascent, due to injury or unconsciousness, or the casualty cannot make a safe and controlled ascent, perhaps due to the loss or damage of the
diving maskA diving mask is an item of diving equipment that allows scuba divers, free-divers, and snorkelers to see clearly underwater. When the human eye is in direct contact with water as opposed to air, its normal environment, light entering the eye is refracted by a different angle and the eye is unable...
, the rescuer must control the casualty's ascent using the
Controlled buoyant liftThe controlled buoyant lift is an underwater diver rescue technique used by scuba divers to safely raise an incapacitated diver to the surface from depth. It is the primary technique for rescuing an underwater and unconscious diver...
. As the casualty is totally dependent on the rescuer, it is important if the two were to separate underwater the casualty should continue to ascend to the surface in a failsafe way.
The options, in order of desirability, for making the casualty buoyant include:
- inflate the casualty's buoyancy compensator to lift off the seabed, then vent it to make a controlled ascent.
- inflate the casualty's drysuit, if one is worn, to lift off the seabed, then vent it to make a controlled ascent. A drysuit is a less secure buoyancy device than a buoyancy compensator.
- drop the weights casualty's diving weighting system
Divers wear weighting systems, weight belts or weights, generally made of lead, to counteract the buoyancy of other diving equipment, such as diving suits and aluminium diving cylinders....
. This may result in a dangerous and rapid ascent.
- lift, by finning, the casualty into shallower water where gas in the casualty's buoyancy devices will expand, then vent it to make a controlled ascent.
If the casualty is not breathing, an urgent ascent directly to the surface is needed so that resuscitation can take place there. In this situation and if the rescuer needs to do
decompression stopA decompression stop is a period of time a diver must spend at a constant depth in shallow water at the end of a dive to safely eliminate absorbed inert gases from the diver's body to avoid decompression sickness...
s, the rescuer has a dilemma; take the casualty to the surface and increase the risk or severity of the bends, including irreversible injuries or death, or do the stops and kill the casualty.
Making the casualty buoyant on the surface
Having reached the relative safety of the surface, it is important that the casualty does not accidentally re-descend. The usual methods of making the diver positively buoyant are to:
- inflate the buoyancy compensator. This is a routine surfacing drill in some training schemes.
- inflate the drysuit
A diving suit is a garment or device designed to protect a diver from the underwater environment. Modern diving suits can be divided into two kinds:* "soft" or ambient pressure diving suits - examples are wetsuits, dry suits, semi-dry suits and dive skins...
, if one is being worn. The gas in a dry suit is not very secure; it can easily escape from sealsA mechanical seal is a device which helps join systems or mechanisms together by preventing leakage , containing pressure, or excluding contamination.Seal types;*Induction sealing or cap sealing*Adhesive, sealant...
and ventVent may refer to:*Vent , a slit up the back of a jacket or coat*Vent , a valve fitted to the top of a submarine's ballast tanks*Vent , a 2001 album by Caliban...
s. Also, excess gas in the suit tends to make the legs buoyant causing the diver mobility problems.
- drop weights
Divers wear weighting systems, weight belts or weights, generally made of lead, to counteract the buoyancy of other diving equipment, such as diving suits and aluminium diving cylinders....
.
Divers who are out of air will probably not be able to inflate their buoyancy compensator or drysuit using the normal and simple technique of pressing the direct feed injection valve. If their equipment allows it, they may be able to inflate these devices orally or use an integrated gas cylinder (if fitted).
Carrying out artificial ventilation in the water
If the casualty is not breathing, it possible to sustain
respirationIn animal physiology, respiration is the transport of oxygen from the outside air to the cells within tissues, and the transport of carbon dioxide in the opposite direction...
or even restart it by
artificial ventilationArtificial respiration is the act of simulating respiration, which provides for the overall exchange of gases in the body by pulmonary ventilation, external respiration and internal respiration...
(AV) at the surface of the water.
Methods of AV vary depending on diver training organization:
The
BSACBSAC can stand for:*Berkeley Sensor and Actuator Center*Bit Sliced Arithmetic Coding, audio coding from MPEG-4 Part 3*British South Africa Company*British Sub-Aqua Club*British Society for Antimicrobial Chemotherapy*Black Swamp Area Council...
technique works like this:
- the casualty and rescuer are buoyant
- the rescuer is positioned at the side of the casualty's head
In anatomy, the head of an animal is the rostral part that usually comprises the brain, eyes, ears, nose, and mouth...
facing the earThe ear is the organ that detects sound. The vertebrate ear shows a common biology from fish to humans, with variations in structure according to order and species. It not only acts as a receiver for sound, but plays a major role in the sense of balance and body position...
- the rescuer extends the casualty's neck
The neck is the part of the body on many terrestrial or secondarily aquatic vertebrates that distinguishes the head from the torso or trunk. The Latin term signifying "of the neck" is cervical.-Bony anatomy: The cervical spine:...
and closes the mouth by lifting the chin with one hand
- the rescuer pushes the casualty's far shoulder
In human anatomy, the shoulder joint comprises the part of the body where the humerus attaches to the scapula. The shoulder refers to the group of structures in the region of the joint....
upwards with the other hand causing the head the twist towards the rescuer
- the rescuer makes a seal over the casualty's nose
Anatomically, a nose is a protuberance in vertebrates that houses the nostrils, or nares, which admit and expel air for respiration in conjunction with the mouth....
using the rescuer's mouthThe mouth, buccal cavity, or oral cavity is the first portion of the alimentary canal that receives food and begins digestion by mechanically breaking up the solid food particles into smaller pieces and mixing them with saliva...
and exhales to fill the casualty's lungThe lung or pulmonary system is the essential respiration organ in air-breathing animals, including most tetrapods, a few fish and a few snails. In mammals and the more complex life forms, the two lungs are located in the chest on either side of the heart...
s
- the rescuer aims to do 10 inflations per minute if stationary, 2 inflations every 15 seconds if towing
Attracting help
At this stage in the rescue immediate help is needed. Very often, the only people that can provide that help are nearby boat users and people on the shore. Unless the emergency services are very close by or the rescue is beyond the capability of the local rescuers, they will not be on the scene quick enough to be able to provide help. Often with a small group of rescuers the emergency services can only be contacted after the highest priority job of getting the casualty is out of the water has taken place.
Often the rescue can be quickened if a boat can come to the casualty rather than a rescuer having to tow the casualty to safety. Once at the surface, using many rescuers becomes feasible; they can communicate and co-operate to make the rescue more efficient.
Methods of attracting help include shouting, waving a straight arm, flag or
surface marker buoyA Surface Marker Buoy, SMB or simply a blob is an inflatable buoy used by SCUBA divers, with a line, to mark the diver's position to their surface, safety boat while the diver is underwater.- Surface Marker Buoy :...
, blowing a whistle, flashing or swinging a torch/flashlight at night, or using a strobe at night. Cylinder powered, high-pressure gas whistles may be effective even over the sound of engines.
Towing the casualty
If the casualty is incapacitated or exhausted, help is needed to move the casualty to safety. Towing is time consuming and will exhaust the rescuer, especially in rough water, currents, or if the rescuer is wearing high-drag equipment such as a drysuit or carrying bulky equipment.
It may be possible to avoid a tow by using a boat to pick up the casualty and rescuer. Alternatively, ropes thrown to the rescuer can be used to pull the pair towards safety.
Removing the casualty from the water
Urgently lifting an injured or incapacitated casualty from the water is a significant problem especially where there are few rescuers, the sea is rough sea, the boat has high sides or the rescuers on the shore cannot get in or close to the water to help.
RopeA rope is a length of fibers, twisted or braided together to improve strength for pulling and connecting. It has tensile strength but is too flexible to provide compressive strength...
s can be very useful, but some precautions are need:
- avoid looping the rope so that it goes round the chest, preventing breathing, or the neck, causing asphyxia
Asphyxia is a condition of severely deficient supply of oxygen to the body that arises from being unable to breathe normally. An example of asphyxia is choking...
.
- when near boats, keep the minimum rope in the water to prevent fouling propellors
- the minimum safe diameter is 12 mm, 1/2 inch. The rope should be doubled to increase the area of contact and reduce the lifting pressure on the casualty.
"Purbuckling" can be used to lift a casualty from the water up a 1.5 metre / 5 foot vertical surface such as a high sided boat, pontoon or a jetty. For a 1.5 metre lift, a length of rope of at least 4 metres / 13 feet is needed. The casualty is brought horizontally alongside. A rescuer in the water with the casualty takes the loop of rope under the casualty and passes it back to two rescuers on "land". The loop of rope is positioned so that in passes outside the arms between the
shoulderIn human anatomy, the shoulder joint comprises the part of the body where the humerus attaches to the scapula. The shoulder refers to the group of structures in the region of the joint....
and elbow and around the outside of the legs between the
kneeThe knee joint joins the thigh with the leg and consists of two articulations: one between the femur and tibia, and one between the femur and patella. It is the largest and most complicated joint in the human body. The knee is a mobile trocho-ginglymus , which permits flexion and extension as well...
and the hip. The two rescuers on land secure the end of the loop that they control by standing heavily on it with one foot. They both pull on the central part of the loop rolling the casualty up the surface taking care to co-ordinate the
tensionIn physics, tension is the magnitude of the pulling force exerted by a string, cable, chain, or similar object on another object. It is the opposite of compression. As tension is the magnitude of a force, it is measured in newtons and is always measured parallel to the string on which it applies...
so that the casualty remains horizontal and that the rope remains in position on the casualty's arms and thightd. A rescuer should take care of that the casualty's head and neck is not damaged during the lift.
An alternative method of lifting the casualty using a rope is to pass the rope under an arm, around the back and under the other arm. The casualty is lifted vertically. There is a risk of spine damage by bending if the casualty is positioned with his or her back to the vertical surface and the rescuers pull the casualty's shoulders in board before lifting the lower end of the torso over top of the vertical surface.
Providing first aid
If the casualty is not breathing
artificial respirationArtificial respiration is the act of simulating respiration, which provides for the overall exchange of gases in the body by pulmonary ventilation, external respiration and internal respiration...
must be provided continuously. It is more likely to succeed if it is started promptly. If the casualty is showing no signs of
circulation- [Headline text]--75.137.171.242 01:21, 21 October 2009 :bThe circulatory system is an organ system that passes nutrients , gases, hormones, blood cells, nitrogen waste products, etc. to and from cells in the body to help fight diseases and help stabilize body temperature and pHb to maintain...
,
chest compressionChest compression may refer to:* The prevention of the expansion of the chest, see Compressive asphyxia* A technique used during cardiopulmonary resuscitation...
are needed. See main article:
cardiopulmonary resuscitationCardiopulmonary resuscitation is an emergency medical procedure for a victim of cardiac arrest or, in some circumstances, respiratory arrest...
.
If the casualty has injuries the rescuers will need to provide first aid and prepare the casualty to be transported to professional medical help. See main article:
first aidFirst aid is the provision of initial care for an illness or injury. It is usually performed by a lay person to a sick or injured casualty until definitive medical treatment can be accessed. Certain self-limiting illnesses or minor injuries may not require further medical care past the first aid...
.
In the developed world, transporting a diving casualty to
hospitalA hospital is an institution for health care providing patient treatment by specialized staff and equipment, and often but not always providing for longer-term patient stays....
or a
recompression chamberA recompression chamber is a pressure vessel used to treat divers suffering from certain diving disorders such as decompression sickness.Often the terms recompression chamber, decompression chamber, hyperbaric chamber, and hyperbaric oxygen therapy chamber are used interchangeably...
may be as simple as contacting the
marine emergency servicesA coast guard or coastguard is a national organization responsible for various services at sea. However the term implies widely different responsibilities in different countries.-Role:...
, generally by using
marine VHF radioMarine VHF radio is installed on all large ships and most motorized small craft. It is used for a wide variety of purposes, including summoning rescue services and communicating with harbours, locks, bridges and marinas, and operates in the VHF frequency range, between 156 to 174 MHz...
, telephone or a
distress signalA distress signal is an internationally recognized means for obtaining help. Distress signals take the form of or are commonly made by using radio signals, displaying a visually detected item or illumination, or making an audible sound, from a distance....
, and arranging a
lifeboatThe meaning of lifeboat or motor lifeboat, for the purposes of this article, is that of 'a shore-based boat designed with special features for searching for, rescuing and saving the lives of people in peril at sea in inshore waters'. This is in contrast to a survival craft type of lifeboat that is...
or
helicopterA helicopter is an aircraft that is lifted and propelled by one or more horizontal rotors, each rotor consisting of two or more rotor blades. Helicopters are classified as rotorcraft or rotary-wing aircraft to distinguish them from fixed-wing aircraft because the helicopter achieves lift with the...
. If a diving injury such as
decompression sicknessDecompression sickness describes a condition arising from the precipitation of dissolved gasses into bubbles inside the body on depressurisation...
is suspected, the success of recompression therapy as well as a decrease in the number of recompression treatments required has been shown if first aid oxygen is given within four hours after surfacing. In other parts of the world and particularly in remote location, it may be difficult to quickly arrange reliable emergency medical transport and treatment; good
insuranceInsurance, in law and economics, is a form of risk management primarily used to hedge against the risk of a contingent loss. Insurance is defined as the equitable transfer of the risk of a loss, from one entity to another, in exchange for a premium, and can be thought of as a guaranteed and known...
and self-reliance are needed.
In-water recompressionIn-water recompression or underwater oxygen treatment is the emergency treatment of decompression sickness of sending the diver back underwater to allow the gas bubbles in the tissues, which are causing the symptoms, to resolve...
is a high-risk alternative that may be useful in locations where the casualty would not survive the journey to the nearest
recompression chamberA recompression chamber is a pressure vessel used to treat divers suffering from certain diving disorders such as decompression sickness.Often the terms recompression chamber, decompression chamber, hyperbaric chamber, and hyperbaric oxygen therapy chamber are used interchangeably...
due to its distance.
Precautions during the rescue
Rescuers should not take unacceptable risks; any rescuers who become casualties themselves may jeopardise the rescue of the original casualty particularly as many of the emergency resources available at dive site, such as rescue manpower, first aid oxygen, underwater time and gas are generally in short supply.
Conscious casualties may panic and put the rescuer's safety at risk particularly when the rescuer approaches a casualty in or under the water. It may be possible to avoid contacting a panicked casualty by throwing a rope or
buoyancyIn physics, buoyancy is the upward force that keeps things afloat. The net upward buoyancy force is equal to the magnitude of the weight of fluid displaced by the body. This force enables the object to float or at least seem lighter....
aid and encouraging the casualty to help him or herself. If contact must be made, the rescuer should try to approach the casualty from a direction that presents least risk to the rescuer, such as from behind. Alternatively, the rescuer may need to wait until the casualty is incapacitated before approaching.
See also
- Diving hazards and precautions
Divers face specific physical and health risks when they go underwater or use high pressure breathing gases. Some of these conditions also affect people who work in raised pressure environments out of water, e.g...
- resuscitation
- first aid
First aid is the provision of initial care for an illness or injury. It is usually performed by a lay person to a sick or injured casualty until definitive medical treatment can be accessed. Certain self-limiting illnesses or minor injuries may not require further medical care past the first aid...
- oxygen first aid
- artificial respiration
Artificial respiration is the act of simulating respiration, which provides for the overall exchange of gases in the body by pulmonary ventilation, external respiration and internal respiration...
- recompression chamber
A recompression chamber is a pressure vessel used to treat divers suffering from certain diving disorders such as decompression sickness.Often the terms recompression chamber, decompression chamber, hyperbaric chamber, and hyperbaric oxygen therapy chamber are used interchangeably...
- diving cylinder
A diving cylinder, scuba tank or diving tank is used to store and transport high pressure breathing gas as a component of SCUBA . It provides gas to the SCUBA diver through the demand valve of a diving regulator.Diving cylinders typically have an internal volume of between and a maximum pressure...
- diving regulator
A diving regulator is a pressure regulator used in a scuba set that supplies the diver with breathing gas at ambient pressure from one or more diving cylinders. The gas may be air or one of a variety of specially blended breathing gases...
- diving equipment
The fundamental item of diving equipment used by divers is the SCUBA equipment, such as the Aqualung or Rebreather. There are other important pieces of equipment that make diving safer, more convenient or more efficient.-Scuba life support:...
- marine VHF radio
Marine VHF radio is installed on all large ships and most motorized small craft. It is used for a wide variety of purposes, including summoning rescue services and communicating with harbours, locks, bridges and marinas, and operates in the VHF frequency range, between 156 to 174 MHz...
- distress signal
A distress signal is an internationally recognized means for obtaining help. Distress signals take the form of or are commonly made by using radio signals, displaying a visually detected item or illumination, or making an audible sound, from a distance....
- Emergency position-indicating rescue beacon
External links