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1. Is oxygen a flammable gas?
2. What type of oxygen does the BioPak require?
3. Can welding-grade oxygen be utilized in the BioPak oxygen cylinder?
4. What is the difference between aviation grade and medical grade oxygen?
5. What is USP Oxygen?
6. When filling oxygen cylinders to 3000 psi (207 bar) on a booster pump the cylinder pressure may drop over time. How can I ensure that a perfect fill to 3000 psig (207 bar) is achieved?
7. Why is it important to keep the booster pump cylinder fill adapters, the BioPak regulator and the BioPak regulator cylinder seal free of grease, oils and dirt?
8. How does one determine if the carbon fiber oxygen cylinder of the BioPak has been damaged to the extent that it should be taken out of service?
9. Why is it important to use the exact type of cylinder seal on the BioPak regulator on the booster pump filling adapters?

Is oxygen a flammable gas?
Oxygen is classified as a strongly energetic oxidizing gas and by itself is not flammable. A flammable gas is one that will act as a fuel that will burn in the presence of oxygen. Thus oxygen is not a flammable gas but is an oxidizer. In the presence of oxygen concentrations above atmospheric pressure and concentrations, materials that readily burn in atmospheric conditions will burn more vigorously and may spontaneously combust; and, materials that normally do not burn in atmospheric conditions may burn in the presence of oxygen concentrations above atmospheric pressure and concentrations.

What type of oxygen does the BioPak require?
The BioPak requires the use of oxygen as specified in the User and Benchman manuals. Oxygen must be certified as medical or aviation grade. The use of other types of oxygen may result in user sickness and/or death from impurities, BioPak flow restriction from entrained particulates or BioPak corrosion from entrained moisture.

Can welding-grade oxygen be utilized in the BioPak oxygen cylinder?
NO! Only medical or aviation grade oxygen, as specified in the manuals, can be utilized in the BioPak oxygen cylinders. Other grades of oxygen may contain high levels of contaminates, such as acetylene, carbon dioxide, carbon monoxide or nitrous oxides, that may lead to user poisoning. Welding grade oxygen cylinders are actually filled with the same USP (United States Pharmacopoeia) oxygen grade as supplied for aviation or medical grade cylinders. The difference is that welding grade cylinders are not evacuated into a vacuum between fills and thus run the risk of containing contaminates (most notably acetylene) left over from improper use or closing by the previous owner.

What is the difference between aviation grade and medical grade oxygen?
Aviation and medical grade oxygen is actually the same USP (United States Pharmacopoeia) oxygen grade material. The difference between the two grades actually is in the handling of the finished gas cylinder and the processing of the gas going into the cylinder. Aviation grade oxygen undergoes an additional drying process to prevent freezing at high altitudes where this gas is commonly utilized. The moisture content of aviation grade oxygen will be guaranteed and the cost of aviation grade oxygen is usually higher than that of medical grade oxygen. Medical grade oxygen cylinders are filled with the same gas as aviation grade cylinder less the extra moisture processing. Medical grade oxygen is handled and regulated in the same manner as a prescription drug so some users may have difficulty in obtaining this grade of gas.

What is USP Oxygen?
UPS oxygen is oxygen gas that meets minimum content requirements set by the United States Pharmacopoeia of 99.0 mole % oxygen, maximum 300 ppm carbon dioxide and maximum 10 ppm carbon monoxide. There are seven different grades of USP gas of A, B, C, D, E, F and G. Each grade will have specific requirements for concentrations of oxygen (none lower than 99.0 mole %), water, methane, nitrogen, ethylene, acetylene, carbon dioxide (non higher than 300 ppm), carbon monoxide (none higher than 10 ppm), total hydrocarbons (as methane) ethane and other hydrocarbons, nitrous oxide, halocarbons and solvents as well as dew point levels.

When filling oxygen cylinders to 3000 psi (207 bar) on a booster pump the cylinder pressure may drop over time. How can I ensure that a perfect fill to 3000 psig (207 bar) is achieved?
When oxygen cylinders are filled with a booster pump, the oxygen will become heated due to the work of compression. The heated oxygen will expand and provide additional pressure within the oxygen cylinder. As the cylinder cools the oxygen will contract and the cylinder pressure will lower. The amount of heating and expansion will depend upon a number of factors including speed of filling, amount of filling and source oxygen pressure. To get a “perfect” fill, the cylinder should be allowed to fully cool and then topped off again to the proper level.

Why is it important to keep the booster pump cylinder fill adapters, the BioPak regulator and the BioPak regulator cylinder seal free of grease, oils and dirt?
All of these components will be exposed to 100% concentrations of oxygen at high pressure; and, during oxygen filling these components will also be exposed to high velocities of oxygen as well as pulsations. The presence of grease, oils or dirt on these components provides fuel that could support a fire or explosion due to the heat of filling or the impact of grease, oils or dirt onto the surface of these components. In the presence of oxygen concentrations above atmospheric pressure and concentrations, materials that readily burn in atmospheric conditions will burn more vigorously and may spontaneously combust; and, materials that normally do not burn in atmospheric conditions may burn in the presence of oxygen concentrations above atmospheric pressure and concentrations. Thus IT IS EXTREMELY IMPORTANT to always keep booster pumps components, cylinder fill adapters, BioPak regulator components and BioPak cylinder seal washers free of grease, oils and dirt to limit the potential for fire or explosion by limiting the presence of any fuel.

How does one determine if the carbon fiber oxygen cylinder of the BioPak has been damaged to the extent that it should be taken out of service?
Local regulations will dictate what damage would require pulling a cylinder from service. The user should conduct regular visual inspections of the oxygen cylinder during each turn around maintenance cycle to verify that 1. There are no exposed fibers on the exterior wrap of the cylinder, 2. There is no evidence of external epoxy chipping or peeling, and, 3. There is no evidence of impact to the exterior of the cylinder. Questionable cylinders should be submitted to a local qualified inspection agent for full inspection. Reference the BioPak 240R website for some cylinder inspection details.

Why is it important to use the exact type of cylinder seal on the BioPak regulator on the booster pump filling adapters?
The connection of the cylinder to the BioPak regulator is exactly the same size and type as the connection of the cylinder to the booster pump cylinder fill adapters so the exact same size and type of sealing washer is required for both connections. The use of any other cylinder seal type may lead to leaking connections.