OXYGEN CLEAN
The Importance of Clean Equipment When Using Pure Oxygen for Diving
When using pure oxygen for diving, it is crucial to use oxygen-clean tanks and, most importantly, clean valves. This also applies on regulators – at least if you intend to using a gas mixture where the oxygen ratio is higher than (normally) 40 %. But why is this necessary? Lets have a look at valves and tanks.
The short explanation is that, although oxygen itself is not an explosive gas, it becomes a significant hazard when forced through a narrow space (creating friction) in the presence of contaminants. These contaminants can create a potentially explosive situation.
While the tank, with its wider opening and likewise bigger interior, poses less of a risk, the valve is the critical component where such dangers are most likely to occur. This is one reason why it is important for tank fillers to check the labels confirming that the tank is suitable for oxygen use and has been properly cleaned and annually inspected to ensure the safety for everyone, and especially for the fillers.
During the thorough cleaning process, it is also vital to inspect the valve components between the different cleaning stages. Personally, I use a 10x or 5x magnifying loupe for this task.
Finally it i important when filling tanks with pure oxygen that the filling process is slow and that the filler is attentive to the tank preventing it to become to warm.
Does it sounds simple?
When inspecting a tank, a simple glance is far from sufficient. Here’s a breakdown of the major key steps to consider:
External Inspection
- Examine regulatory markings on the tank and look for signs of rust, corrosion, or other damage.
- Check for deformation, such as “banana-ing” (a noticeable curve or bend in the tank).
Internal Inspection
- Conduct a sniff test to detect any unusual odors inside the tank.
- Inspect the threads and neck of the cylinder using tools such as a dentist’s mirror, a 10x magnifying loupe, and proper lighting.
- Look for signs of rust or corrosion inside the tank.
Actions Based on Findings
• Depending on the results of the inspection, appropriate measures must be taken.
• If the tank is intended for use with nitrox or pure oxygen, specific cleaning methods must be applied.
Filling a tank with oxygen
Even though a tank and its valve has been approved as “oxygen clean” It is still very important when filling tanks with pure oxygen, that the filling process is slow and that the filler is attentive to the tank preventing it to become to warm. Those of you using a booster should pay even more attention to this.