Sight Search

COVID-19 Advisory

As you might imagine, DAN has received a number of enquiries regarding the current COVID-19 Pandemic.
 
We have already issued travel advisories for DAN Southern Africa Members, and for SouthAfricans there are the restrictions on travel issued by our President as part of the 21-day lock-down. Other countries in and outside our DAN Southern Africa region have issued similar restrictions, and these should be heeded.
 
There is a lot of fake news floating around, so we encourage you to verify facts and consult reputable sources for information.  The formal COVID-19 websites of the National Institute for Communicable Diseases contains up-to-date information and we will post (verified) information that is relevant to divers as they become available.
 
So, with that preamble, I want to start by saying that we will not be addressing the typical COVID-19 issues in this Factoid Issue, but rather selected responses to questions posed by DAN Members, including those who may still be in remote areas and may be wondering how to manage their limited resources optimally. There is something relevant for everybody.

Here are four questions we received that offer a backdrop for the answers we would like to provide:
 
Firstly: Could you help me to get a plan on how to assist somebody with breathing problems (due to Covid 19) with the oxygen that we keep here at the dive center?
 
Secondly:  As we are without any medical assistance in a remote area and would like to have a simple protocol to follow if any of my family gets sick and we have some oxygen available for diving emergencies. How much oxygen should we give? By what method; and for how long? Please advise.
 
Thirdly: I am a DAN O2 Provider and Instructor and have the following question for you: I have a DAN O2 rescue pack with two 6-Liter cylinders. Would a flow rate of 15 Lpm be of any use to a person with respiratory symptoms due to COVID-19? If not, what do you suggest?
 
And Fourthly: Could Hyperbaric Oxygen help people suffering from COVID-19
 
These are all very relevant questions. For the first three, I would like to refer you back to the downloadable DAN Guidebook “Prepare don’t Panic” which is on the DAN SA Blog. I do want to speak to the issue of oxygen utilisation, moving symptomatic individuals, and hyperbaric oxygen therapy, however.
 
Limited supplies of oxygen and difficulties in gaining access to specialised medical assistance are definitely some of the pressing challenges.

But, before addressing these, let us not forget the primary advice on social distancing, self-quarantining and self-isolation. Self quarantining means staying in the same building with other potentially exposed but asymptomatic individuals. Self-isolation, means isolating symptomatic individuals (where there is a very high suspicion that their symptoms are due to COVID-19 due to contact with other COVID-19 positive individuals or travel from high-risk areas). These individuals should keep themselves in a separate room and use only their own linen and cutlery.
 
The main concern is for individuals in self-isolation: when should one move them to further medical care and, if the decision is made to do so, how to optimise the use of any available oxygen?
   
To keep things simple I would like to offer four key considerations which may be relevant depending on the specific situation:
 
1. As with all our DAN First Aid Courses, Provider Safety is vital. So, wear gloves, and use or improvise masks and eye protection, if you do not have professional masks and splash guards, as necessary, but try to shield your own mouth, nose and eyes while assisting a symptomatic individual.

2.  Remember that there may be other diseases like influenza, tick-bit fever, malaria, traveller's diarrhoea or dysentery that may mimic COVID-19 infection and for which isolation may lead to a disastrous outcome completely unrelated to COVID-19, particularly malaria. If you are in a malaria area, and the individual started developing symptoms after being in an area with infected mosquito exposure for at least 7 days (especially if there are no or only incidental respiratory symptoms), please assume the high probability of malaria and treat them for it if fever and flu-like symptoms develop, while keeping the person isolated from other asymptomatic individuals. Refer to our material on malaria for this purpose. Also advise individuals who are still at risk of contracting malaria to implement the prescribed anti-malaria precautions, especially during the 21-day period of the lockdown, including taking doxycycline or Malarone/ Malanil and even Mefloquine (Lariam) as they are not going to be diving for a while, and the risk of malaria becomes greater than the risk of adverse medication reactions after 14 days.

3. Encourage honesty so that people admit symptoms earlier. If respiratory symptoms and breathlessness reach the point where the individual is showing obvious signs of escalating respiratory distress (and especially if there is relentless coughing, breathing at rates in excess of 25-30 per minute, or cyanosis (which is where the lips and skin takes on a bluish colour; this is a definite turning point in moving a symptomatic individual if there is a reasonable chance of getting to a higher level of medical care and respiratory support.

4. Lastly, the issue of Oxygen: Breathing oxygen via a demand valve remains the least wasteful way of providing oxygen. If the person has the strength to breathe through an O2 Demand Valve they should do this at a frequency that is just sufficient to offer some relief of critical symptoms.  Pulses of oxygen will allow supplies to last longer. If there is no oxygen demand valve, connect the oxygen supply to a pocket mask, set the flow rate on 0.5-1 Lpm oxygen and have the person breathe through the filter fitted to the Pocket mask. Using a pocket mask also protects those caring for the individual to some extent. Try to stretch your supplies as best you can while considering the distance and time to getting to medical care. Also, the longer the distance, the earlier you may want to consider moving the individual. Note that nasal prongs may aerosolise viruses; non-rebreather masks require flow rates that are too high and wasteful. So both of these are impractical with limited supplies of oxygen. Some serious cases can deteriorate rapidly within 2-3 hours, so do not delay cases where the suspicion of COVID-19 is high. Be aware of the potential fire risk when using oxygen in enclosed spaces and – as said before – rather give “bouts” of oxygen as required to ease symptoms as you make your way to a medical facility.

Importantly, we would advise you (as far as possible) not to attempt to treat a person getting ill with potential COVID-19.  

Some high-risk individuals have deteriorated quite fast and it is therefore important to have medical care available if this is possible, rather than thinking that oxygen alone would cure the disease.
 
In closing, just a brief comment on Hyperbaric Oxygen: It is not readily available and requires highly trained critical care staff who are familiar with the complications of using hyperbaric oxygen, if its use is to be considered in COVID-19 patients. It is most certainly not considered a standard of care at this stage. For those interested, a reference is provided on a series of cases treated with HBO. However, this is a relatively low level of evidence and should not delay getting persons to conventional intensive medical care.
 
Thank you for watching this DAN Factoid on oxygen and COVID-19. Please remember to refer to the guidebook on “Prepare, don’t panic”, by DAN.

We also invite you to visit the COVID-19 Updates section of our website, where you will find regular updates regarding the COVID-19 outbreak
Posted in
Tagged with

Categories

 2022
immersion and bubble formation 232bar AGE AIDA Accident management Accidents Acid reflux Acute ailments Advanced courses Rescue diver Aerobic exercise After anaesthesia Aged divers Air Quality Air exchange centre Air hose failure Air supply Airway control Air Alert Diver Magazine Algorithms Alice Cattaneo Alice Modolo Alternate Airsources use Alternater Air Source Alternative gas mix Altitude changes Altitude diving Altitude sickness Aluminium Oxide Ama divers Amino acids Amos Nachoum Anaerobic Metabolism Animal life Annual renewal Antarctica Anxiety Apex predators Apnea Apnoea Aqua corps Aquatic creatures Aquatic life Aquatics and Scuba Diving Archaeology Argonaut octopus Argonauts Argon Arrythmia Arterial Gas Embolisms Arterial gas embolism Arthroscopic surgery Aspirin Audible signals Aurel hygiene Australian Flat backed BCD BHP BLS BWARF Back adjustment Back pain Back treatment Backextensors Backmount CCR Badages Bag valve mask Bahamas Balancing Bandaids Barbell back squat Barometric pressure Barotrauma Basic Life Support Batteries Beach entry Becky Kaga Schott Becky Kagan Schott Bench press Bends Benign prostate hyperplasia Benzophenones Beth Neale Beyond Standards Bilikiki Tours Biophysics Black Blood flow Blood pressure Blood thinners Blue Desert Blue Wilderness Blue economy Blurred vision Boat diving Boat safety Boesmans gat Boesmansgat Bonaire Bone fractures Bouyancy compensators Bouyancy controls Boyle's Law Boyle\'s Law Bradycardia Brain Brandon Cole Breast Cancer Breath Hold Diving Breath hold diver Breath holding Breath hold Breath-hold Breathing Gas Breathing gas contamination Breathing Breathold diving Bright Bank Broken bones Bruising Bubble detection Bubbleformation Buddy Exercise Buddy checks Buoyancy Burnshield CCR CGASA CMAS CO2 COVID-19 Updates COVID-19 COVID CPR Cabin pressure Caissons diseas California Camera equipment Camera settings Cameras Cancer Remission Cancer treatments Cancer Cannabis and diving Cannabis Cape Town Dive Festival Cape Town Dive Sites Cape Town CapeTown Carbon Monoxide Carbon dioxide Cardiac research Cardiaccompromise Cardio health Cardiological Cardiomyopathy Caribbean Carmel Bay Catalina Island Cave diving Cave exploration Cave Challenging Environments Chamber Safety Chamber science Chamber treatment Charging batteries Charles' Law Charles\' Law Charles\\\' Law Charles\\\\\\\' Law Charles\\\\\\\\\\\\\\\' Law Charlie Warland Chemotherapy Chest compressions Children diving Chiropractic Chlorophll Chokka Run Christina Mittermeier Citizen Conservation Citizen sciences Citizen science Clean Air Cleaning products Closed Circuit Rebreathers Closed Circuit Rebreather Cmmunity partnership Coastal diving Coastalexcursion Cold Water Cold care ColdWater Cold Commercial Fishing Commercial diving Commercial schools Common consideration Common understanding Communication Composition Compressed Air Compressed gas Compressor operators Compressors Concussion Congestive heart Faiture Consercation Conservation Photographer Conservation photography Conservation Contact lenses Contaminants Contaminated air Coping with cold Coral Conservation Coral Reefs Coral Restoration Coral bleaching Coral preservation CoralGroupers Corals Core strength Corona virus Coro Costamed Chamber Courtactions Cozumel Cradiac valvular Cristina Mittermeier Crohns disease Crowns Crystal build up Crystallizing hoses Cutaneous decompression Cylinder Ruptures Cylinder capacity Cylinder handwheel Cylinder safety Cylinder valves Cylinder weight DAN Courses DAN Profile DAN Researchers DAN medics DAN members DAN report DANTraining DCI DCS Decompressions sickness DCS theories DCS DEMP DM training DNA DReams Daan verhoeven Dahab Dalton's Law Dalton\'s Law Dalton\\\'s Law Dalton\\\\\\\'s Law Dalton\\\\\\\\\\\\\\\'s Law Danel Wenzel Dangerous Marinelife Dauin island Dave McCowan David Doubilet Dean's Blue Hole Dean\'s Blue Hole Deco dives Decompression Illness Decompression Sickness Decompression Stress Decompression chamber Decompression illsnes Decompression limits Decompression treatment Decompression Decorator crabs Deep Freediving Deep diving Deep water exploration Deepest SCUBA Dive Delayed Offgassing Dental Depth limits Dever Health Diagnosis Diaphragms Diopter Diseases Disinfection Dive Buddy Dive Chamber Dive Computer Dive Destinations Dive Destination Dive H Dive Industry Dive Instruction Dive Instructor Dive Medical Form Dive Medical Dive Practices Dive Professionals Dive Pros Dive Rescue Dive Research Dive Safari Dive Safety Tips Dive South Africa Dive Training Dive Travel Wakatobi Dive Travel Dive accidents Dive buddies Dive computers Dive courses Dive cylinder Aluminium Dive excursions Dive exercise Dive exeriences Dive experience Dive fitness Dive gear Dive heallth Dive health Dive in Africa Dive medicals Dive medicines Dive medicine Dive operators Dive opportunities Dive planning Dive procedures Dive safety 101 Dive safety Dive safe Dive skills Dive staff Dive travels DiveLIVE DiveTravel Diveleader training Diveleaders Diver Health Diver Profile Diver Travel Diver education Diver infliencers Diver on surface Diver recall Diverover 50 Divers Alert Diversafety Divesites Diving Divas Diving Fatalities Diving Feet Diving Kids Diving Programs Diving Trauma Diving career Diving emergencies Diving emergency management Diving fit Diving guidelines Diving injuries Diving suspended Diving Dizziness Dolphins Domestic Donation Doug Perrine Dowels Dr Rob Schneider Drift diving Drysuit diving Drysuit valves Drysuits Dynamic environment Dyperbaric medicines EAPs EAP EMS Ear barotrauma Ear pressure Ear wax Ears injuries Eco friendly Ecowise Education Electronic Emergency Action Plan Emergency Planning Emergency action planning Emergency decompression Emergency plans Emergency treatments Emergency underwater Oxygen Recompression Emergency Endurance Envenomations Enviromental Protection Environmental factors Environmental impact Environmental managment Environmental stewardship Equalisation Equalization Equipment care Equipment failure Equipment inspection Equipment significance Evacuations Evacuation Evaluations Even Breath Evironmetaly friendly Exercise Exercising Exhaustion Exposure Protection Extended divetime Extinguisher Extreme treatments Eye injuries FAQ Face computer Factor V Leiden Failures FalseBay Diving Fatigue Faulty equipment Feet Femal diver Female divers Fetus development Filling stations Fillings Fin Foot Fire Coral Fire Safety Fire extinguisher Firefighting First Aid Equipment First Aid Kit First Aid Trainig First Aid Training First Aid kits First Aid Fish Identification Fish Life Fish Fit to dive Fitness Levels Fitness Training Fitness evaluation Fitness to dive Fitnesstrainng Fitness Flying Focus lights Footissues Foundations Fractures Francesca Diaco Francois Burman Fred Buyle Fredive Free Student cover Free diving Free flow Freedive Competition Rules Freedive Competiton Freedive INstructor Freedive Safety Freedive Training Freedive computer Freedive rescue procedures Freediver Freedive Freediving Instructors Freediving performance Freediving Gar Waterman Gas Density Gas consumption Gas emboli Gas laws Gas mixes GasPerformance Gasblends Gases Gass bubbles Gastoeusophagus Gastric bypass Gastroenterologist Gas Gear Servicing Germs Geyer Bank Giant Kelp Forest Giant Kelp Giant stride Girls that Scba Gobies Gordon Hiles Great White Sharks Green sea turtle Greenlings Guinness World Record Gutt irritations HBOT HCV HELP HIRA HMLI HMS Britanica Haemorhoid treatment Hand signals Harry Chammas Hawaii Hawksbill Hazard Description Hazardous Marine life Hazardous marinelife Head injuries Headaches Health practitioner Heart Attack Heart Health Heart Rate monitor Heart fitness Heart rates Heart rate Heart Heat stress Heliox Helium Hematoma Hemodynamic Hepatitis C Hepatitus B Hiatal Hernia High Pressure vessels High pressure hoses High temperatures Hip strength Hip surgery Hippocampus History Hole in the heart Hood Hot Humans Hydrate Hydration Hydrogen Hydroids Hydrostatic pressure Hygiene Hyperbaric Chamber Hyperbaric Oxygen Treatments Hyperbaric Oxygen Hyperbaric research Hyperbaric treatment Hyperbarics Hypertension Hypothermia Hypoxia I-52 found INclusivity IdentiFin Imaging Immersion Immine systems In Water Recompression Increased pressure Indemnity form Indian Ocean Indigo SCuba Indonesia Inert gas Infections Infra red Imaging Injections Inner ear Instinct Instruction Instructors Insurance Integrated Physiology International travel International Internship programs Internship Interval training Irritation Irukandji Syndrome Isotta housing Itchy Rash Jellyfish Jill Heinerth Joanna Wyrebek Joint pain Journal for Technical Diving Junior Open Water Diver KZN South Coast KZN Karen van den Oever Kate Jonker KateJonker Kenya Kidneys Kids scubadiver Komati Springs KwaZulu Natal LED lights Labour laws Lake Huron Lara Lambiase Laryngospasm Lauren Arthur Learning to dive Leatherback Legal Network Legal advice Legislation Lembeh Straights Lenses Leukemis Liability Risks Liability releases Liability Life expectancy Lifestyle Lighting Lightroom editing Lionfish Live aboard diving Liveaboard Liver Toxicity Liver diseas Liz Louw Loss of consciousness Lost at sea Low Visability Low blood pressure Low pressure deterioration Low volume masks Lumpsuckers Lung Irritation Lung function Lung injuries Lung squeeze Lung surgery Lung MOD MOzambique diving Macro photography Mafia Island Maintenance Malaria Mammalian Dive Response Mammalian effect Mandarin Fish Marfan syndrome Marine Biology Marine Mega fauna Marine Science Marine Scientists Marine conservation Marine parks Marine plants Marinelife Marinescience Markus Dirschi Marlin Mask clearing Masks Master scuba diver Maximum operating depth Medical Q Medical emergencies Medical questionaire Medical statement Medical team Medicalresearch Medicalstudents Medication Mehgan Heaney-Grier Membership benefits Menopause Menstruation Mermaid Danii Mesophotic Metotrexate Mexico Michael Aw Microbubbles Middle ear pressure Mike Bartick Military front press Misool Resort Raja Ampat Mixed Gas Mono Fins Mooring lines More pressure Motion sickness Motionsickness Mount Kilimanjaro Mozambique Muscle pain Mycobacterium marinum NDL limits Narcosis National Geographic Nausea Nautilus Ndibranchs Neck pain Neoprene layers Neuro assessments Neurocognitive research Neurological assessments Neuromotor exercises Nichola Bird Nicorette Nicotine Nitrogen Narcosis Nitrogen build up Nitrox No Decompression Limits No-decompression limits No-decompression Non-nano zinc oxide Non-rebreather Mask Non-smoking Nondiving related illness Nonrebreather masks Normal Air North Sulawesi Nosebleeds Nudibranchs Nuno Gomes O2 oxygen provider. O2 providers O2 servicing O2treatments OOxygen maintenance Ocean Projects Ocean Research Ocean animals Ocean conservation Ocean migrations Ocean pollution Oceangate Octopus Oil contamination Olive Ridley Open Ocean Open water divers Optical focus Oral contraseptives Orbital implants Oronasal mask Osteonecrosis Out and about Out of air Outer ears Outreach Overhead Envirenments Oxygen Administration Oxygen Cylinder Oxygen Units Oxygen deficit Oxygen deicit Oxygen dificiency Oxygen ears Oxygen equipment Oxygen kit Oxygen masks Oxygen providers Oxygen supplies Oxygen supply Oxygen systems Oxygen therapy Oxygen P J Prinsloo PADI Freedivers PFI PFO PJP Tech Paper Nautilus Paralysis Parentalsupervision Part 3 Partner Training Patent foramen ovale Pemba Island Peri-peri Divers Perspective Peter Lindholm Philippine Islands Philippines Phillipines Photographers Photography tips Photography Physical Fitness Physioball Physiology Physiotherapy Pills Pilot Whale Pistons Planning Plastic Plimsoll Interface Pneumonia Pneumothorax Poison Pollution Pool Diving Pool chemicals Pool maintenance Pool workout Pools Post-dive Potuguese man-of-war Pre-dive Predive check Pregnancy Pregnant divers Preparation Prepared diver Press Release Preventions ProDive Port Elizabeth Professional rights Provider course Psycological Pulmanologist Pulmonary Barotrauma Pulmonary Bleb Pulmonary Edema Pulmonary Hypertension Pulse Punture wounds Pure Air Pure Apnea Purge Quit Smoking Q RAID South Africa RCAP REEF Radio communications Range of motion Rashes Rebreather diving Rebreatherdive Rechargeable batteries. Recompression chamber Recompression treatment Recompression Recycle Reef Chcek Reef Conservation Reef Environmental Education Foundation Reef safe Reef surveyors Refractive correction Regal Sea Goddesses Regulator failure Regulators Regulator Remote areas Remote islands Renewable Report incidents Rescue Divers Rescue Procedure Rescue breathing Rescue breaths Rescue diver Rescue skills Rescue skill Rescue training Rescue Research Resume diving Return To Diving Return to diving Reuseable items Risk Assessments Risk assesments Risk assessment Risk elements Risk management Risks of Seizures Roatan Marine Park Roatan SABS 019 SMB SafariLive Safe diving practices Safety Concerns Safety Gear Safety Stop Safety in Air Safety SaherSafe Barrier Salish Seas Salty Wanderer Sanitising Sanne Volja Sara Andreotti Sara Banderby Sara Campbell Sardine Run Sargassum sea Saturation Diving Save our seas Schrimps Science Scoliosis Scombroid Poisoning Scorpion Fish Scuba Air Quality Scuba Guru Scuba Injury Scuba Instructor Scuba children Scuba divers Scuba dive Scuba education Scuba health Scubalearners Scubalife Sea Horses Sea Turtles Sea slugs Seagrass Sealcolonies Sealife Seals Seasickness Seaweeds Seaweed Sea Self Rescue Shallow dives Shark Protection Shark Research Shark conservation Shark diving Sharks Shipwrecks Shit Happens Shore entries Shoulder strength Sidemount Sideplank Signs and Symptoms Silty bottoms Sit-ups Sixgill Sharks Skills in action Skin Bends Skin outbreak Skin rash Smart phone photography Snells Window Snorkeling Snorkels Social Distancing Sodwana Bay Solomon Islands Sonnier bank South Africa SpareAir Sperm Whales Spinal Bend Spinal bends Spinal cord DCS Spinal dura Spinal pain Spinner dolphins Splits Sports medicine Squeezes Squid Run Stability exercise Standars Statin Mediction Stay Fit Steel Stefan Randig Stents Step ups Stephen Frink Stepping up Stockton Rush Stonetown Stretch band exercise Stretch bands Strobe Lighting Strobes Stroke Submerge tech Submerged Sudafed Sulawesi Sun protection Sunscreen Supplemental oxygen Surface Marker Buoys Surface supplied Air Surfaced Surgeries Surgery Suspension training Swim Fitness Swimmers health SwimmingIn wateractivities Swimming Symbiosis Symbiosys TRavel safety Tabata protocol Talya Davidoff Tanzania Tattoes Tec Clark Tech diving Technical Diving Technical divng Temperature Homeostatis The Bends The Cavettes The Titanic Wreck The Wild Coast The greatest Shoal The truth Thermal Notions Thermoregulation Thomas Peschak Thunder Bay National Marine Sanctuary Tides Tips and trick Tonga Tooth squeeze Transplants Travel destinations Travel smarter Travel tips Travel Tropical Coastal Management Tunnelling Turks and Caicos Turtles Tweezers Ultrsound Umkomaas Unconscious diver Unconsciousness Underground work Underseaa world Underwaater Photos Underwater Photography Underwater Photograper Underwater Photograpgraphy Underwater Photographer Manirelife Underwater Research Underwater critters Underwater floral Gardens Underwater hockey Underwater imaging Underwater photographer Underwater photography Underwater pho Underwater sound Underwatercommunications Underwater University of Stellenbosch Unresponsive Urinary retention. VGE Vacations Vaccines Vagus nerve Valsalva manoeuvers Valve stem seals Vape Vaping Vasopressors Vasvagal Syncope Venous gas emboli Ventilate Venting Verna van Schak Videography Vincenzo Ferri. Virus infections Volatile fuels WWII wrecks War stories Washout treatments Wastewater Watchman device Water Resistance Water Weakness Weigang Xu Weights West Papua Western Cape Diving Wet Lenses Wet diving bell Wetsuit fitting Wetsuites Wetsuits White balance Whitetpped Sharks Wide Angle Photos Wide angles Wildlife park Wildlife Winter Wits Underwater Club Wolf Eels Woman and diving Woman in diving Womans health Woman Women In Diving SA Women and Diving Women in Freediving Women in diving Womens Month Womens health Work of Breathing Workout World Deeepst Dive Record World Records Wound dressings Wreck History Wreck divers Wreck dive Wreck diving Wreck exploration Wreckdiving Wrecks Yoga Youth diver Zandile Ndholvu Zanzibar Zoology Zooplankton \ Blennies abrasion absolute pressure acoustic neuroma excision adverse seas air-cushioned alert diver altitude alveolar walls anemia antibiotics anticoagulants antiseptics bandages barodontalgia bent-over barbell rows bioassays biodiversity bloodcells body art breathing air calories burn canal blockage carbon dioxide toxicity cardiovascular career developments cerebrospinal fluid cervical spine checklist chemo port children child chronic obstructive pulmonary disease clearances closed circuit scuba coral growth corrective lenses currents cuts cylinder filling dead lift decompression algorithms decongestants decongestion dehydration dive injuries dive medicing dive ready child dive reflex dive tribe divecomputers diver in distress diver rescue diver training dive diving attraction doctors domestic travel dri-suits drowning dry mucous membranes dry suits dry e-cigarettes ear spaces elearning electrolyte imbalance electroytes emergency action plans emergency assessment emergency training environmentally friendly equalising equalizing exposure injuries eyes fEMAL DIVERS fire rescue fish watching fitness Balance fitnes flexible tubing frediving freedivers gas bubble gas poisoning gastric acid gene expression health heartburn histidine hospital humidity hypobaric hypoxia immersion and bubble formation immersion pulmonary edema (IPE informal education isopropyl alcohol jaundice join DAN knee laparoscopic surgery life jackets longevity lower stress lox oxygen level malaise marielife marine pathogens medical issues medical procedures medical risk assesment medications mental challenge mental preparedness micro-organisims micro minor illness mucous membranes multilineage dysplasia myelodysplasia nasal steroids nasal near drowning nematocysts neurological newdivers nitrogen bubbles off-gassed operating theatre operations orthopeadic otitis media out planting outgas pain parameters perforation phillippines phrenic nerve physical challenges pinched nerves plasters pneumoperitoneum polyester-TPU polyether-TPU post dive posture prescription mask preserve prevention professional emergency responders proper equalization psychoactive pulmonary barotrauma. pulmonary injury. pulmunary barotrauma radiation rebreather mask rebreathers retinal detachment risk areas safety stops saturation scissors scuba equipment scuba sea goddesses single use sinus infections situationalawarenes smoking snorkeling. spearfishing sterilising stings strength sub-aquatic sunscreen lotion swimmers ears tattoo care tecnical diver thermal protection tissue damage toxicity training trimix unified standards upwelling virtual coach vision impaired vomiting warmers water quality zinc oxide