How frequently should standard weight high-pressure oxygen cylinders undergo hydrostatic testing?

High-pressure oxygen cylinders, particularly those used in aviation and medical applications, need to be regularly tested to ensure their safety and functionality. Hydrostatic testing is a critical procedure that assesses the strength and integrity of these cylinders by filling them with water and then pressurizing them to check for leaks or structural weaknesses.

The standard requirement for hydrostatic testing of high-pressure oxygen cylinders is typically every 5 years. This frequency is established to ensure that any potential deterioration from stress, corrosion, or material fatigue is identified and addressed in a timely manner. The 5-year interval allows for safe operation while complying with regulations that govern the handling and use of pressurized gas containers.

Given this context, the choice indicating that high-pressure oxygen cylinders should undergo hydrostatic testing every 5 years aligns with safety standards and regulatory requirements in the industry, making it the correct answer.