Final answer:
In the context of medical gas systems where installed pressures exceed 185 psi, hard-drawn seamless copper tubes must be rigid to handle high pressure without deformation, ensuring safety and reliability.
Step-by-step explanation:
The student's question pertains to the specifications for hard-drawn seamless copper medical gas tube used in systems where pressures exceed 185 psi. According to standards and best practices in medical gas systems, the copper tubing should be rigid. This means that the copper piping is not designed to be bendable or flexible but should maintain a fixed shape to withstand the high pressure without deformation. The use of rigid tubing is crucial for ensuring the reliability and safety of medical gas transport within a healthcare facility.
Flexible tubing would not offer the same level of structural integrity at such pressures, and thus, it is not recommended. While choices like insulation or coating might apply to other scenarios, in the context of this question the correct answer is rigid, as these pipes must be robust and able to handle the described pressure without risk.