Hyperbaric Fire Fighting And Fire Prevention Procedures Peter Manz
To prevent fires a good knowledge of why they start is important
Fuel Oxygen IGNITION FIRE A FIRE REQUIRES PLUS A FOOL TO PUT THEM TOGETHER FIRE OOOPS
Electrical, electrostatic or break arc Hot surface, friction spark or heated wire Heated gases independent of surfaces, generated by adiabatic compression or jets of hot gas Exothermic chemical reaction Mechanical source of friction heating and particle impact Laser sources
This process begins at any increase over 21 % oxygen by volume at 1 ATA Burn rate starts to accelerate considerably after 23.5% oxygen by volume. Therefore at no time will any chamber oxygen level be over 23.5 % If this is not known, consideration should be given to aborting the treatment
When pressure and or oxygen levels increase burns rates also increase (Cook Diagram). These changes also effect ignition temperature, which decreases, significantly Therefore the friendly HBOT system atmosphere is unfortunately well suited to easier ignition and faster burning of fire
Is determined by available oxygen and fuel Control of fuel and oxygen is fundamental in fire management Low oxygen, low fuel, slow / low spread of flame
Mattress Pillows Sheets Clothing, NO POCKETS Paper, books magazines Newspapers? If hot enough and O2 then almost anything will burn
Cotton sheeting NFPA Ch 19 table 126.96.36.199 This shows that increasing oxygen levels combined with raised pressure, lowers the ignition temperature
All occupied chambers must have some pockets of differing gas, Heterogeneous (not well mixed) Therefore it is possible that the measured oxygen concentration may be high in pockets Sheffield showed that this may be minimal PP Curve disperses gas quickly, but possibly not quite evenly New evidence suggests that oxygen may collect near or under the floor plates
We should only have “A” Class material in a chamber If careful control of all material in a chamber is taken (NO POCKETS) Use fire retardant products (seating materials etc) “A” Class material is effectively controlled by using water Also Fires need time to become established
This must be possible No electricity No matches, lighters (NO POCKETS) Nothing should be taken in. Only have what is allowed in the chamber.
If a fire starts water must be available Regular system tests, tx pre tests, and bi annual full tests, must be fastidiously carried out, and the results carefully logged No deaths have occurred, in any chamber when water is quickly available, and the oxygen level is less than 23.5% this is a very achievable goal, and it NEEDS TO BE COMPLIED WITH !!
Water is best medium to fight hyperbaric Fires It must be available quickly Water storage. Water pressure controls delivery
NFPA Independent Air Source Deluge and Hand Held Hoses Minimum Flow for 60 seconds (one minute) How often do you test? Do you record the results?
All occupants on BIBS, protect your own airway FIRST Immediately deluge with water. Inform all of the “Team” Start an emergency ascent These actions should be almost simultaneous Prepare to assist occupants on surfacing Fire may re-ignite on door opening
All events that may occur in a hyperbaric chamber should be considered and planned for. “Normal” procedures and those that deviate from “Normal” are should be covered in the Units Standard Operational Procedures Manual All procedures need to be practiced - regularly These should include the emergency ones
Technical Emergencies Medical Emergencies Fire Emergencies General Emergencies
Loss of pressurizing gas air Loss of primary oxygen Rapid Increase in chamber pressure Rapid decrease in chamber pressure Loss of back up pressurizing gas Loss of back up oxygen source Contaminated breathing gas either source or chamber environment Loss of communications Loss of power
Management of Seizures CNS Oxygen toxicity Cardiac arrest, including defibrillation Barotraumas during descent/ ascent Claustrophobia and acute anxiety Suspected pneumothorax Aggressive or violent patient
FIRE Fire inside the HTS (Chamber) Fire in the room, adjacent area Accidental fire deluge activation GENERAL Omitted decompression. Incapacitation of the technician Illness of the attendant Emergency entry of the outside assistant Requesting help in the chamber area Emergency decompression.
Sources of Ignition: Matches, Lit cigarettes, Cigarette lighters, pocket warmers, Electrical items, radios, torches, batteries, Heat packs, or chemicals, Friction toys, welders spark gun, Unsuitable clothing (Synthetics and pockets) Sources of contamination: Oil, Smell, HP Cylinders, Other Gases, Mercury (Thermometers, BP Devices), some ointments.
Sources of additional fuel: Newspapers, Extra Magazines, Bedding, Unsuitable clothing (Synthetics and having pockets), oily materials, Bandages and ointments. Documentation and Procedures ONLY TAKE IN ESSENTIAL APPROVED MATERIALS, NOTHING ELSE !!!
We should only have “A” Class material in a chamber If careful control of all material in a chamber is taken (NO POCKETS) “A” Class material is effectively controlled by using water Also Fires need time to become established
Fire hazard from high oxygen concentrations Potential explosion of badly handled cylinders Depletion of oxygen supply
The compressed energy of a HP gas cylinder is enormous It will kill, destroy buildings if allowed to Always firmly fix cylinders when stored large ones upright, small ones on side Always use a cart for larger cylinders (fix to cart) Never leave standing up unless it is firmly fixed SNIFT before connecting Always turn on slowly, only use correct pressure rated equipment
The atmosphere By fractional distillation Produces very pure gas Decanted, compressed further into HP cylinders Assures quality Absorption swing system, less pure oxygen
Draws in air Removes CO2, dust, Oil Compressed, cooled to turn gas, air into a liquid. (-196 deg K at ~ 600kPa) Distilled stored Compressed evaporated into cylinders HP pure gas ready for use
Oxygen here is Green (Same as USA), Germany it is blue, UK/ Australia Black with white top Be sure of your gas Analyze is best to be sure be careful when traveling
HP Gas storage cylinders Oxygen manufacture Oxygen hazard Calculating gas supply duration/ needs Hyperbaric oxygen environment (fire risk)
Oxygen supports combustion High oxygen concentrations accelerates burn rate Always ventilate the area Never have exposed flame etc, no smoking where oxygen is being used Oxygen is odorless colorless. It can be present in large dangerous quantities, without being aware of it