What is required for scuba equipment, valves, and cylinders exposed to pure oxygen?

When scuba equipment, valves, and cylinders are exposed to pure oxygen, they must be O2 clean and O2 service rated. This is critical because pure oxygen environments can be highly reactive and pose a risk of fire or explosion if contaminants, such as oils and greases, are present.

Being O2 clean means that the equipment is free from contaminants that could ignite in a pure oxygen atmosphere. This cleaning process involves thoroughly cleaning the components to remove any potential flammable residues. Additionally, being O2 service rated indicates that the materials and construction methods used for the equipment are specifically designed to be safe for use with high concentrations of oxygen, ensuring that they can endure the increased reactivity without posing a hazard.

The other options, while relevant in various contexts, do not address the specific requirements for safe operation in high-oxygen environments. For instance, being Nitrox rated relates more to the compatibility of equipment with Nitrox mixtures rather than pure oxygen. Storing equipment in dry places can help prevent moisture-related issues, but it doesn’t address the need for oxygen compatibility. Air rated equipment is not suitable for use with pure oxygen, as it may not meet the stringent requirements needed for safety.