How is a stationary tank defined?

A stationary tank is defined as a container that typically has a significant water capacity, specifically not less than 1,000 pounds. This definition emphasizes the tank's role in storing larger volumes of non-flammable medical gases in a fixed location, often at healthcare facilities. By specifying the minimum capacity, regulatory frameworks can ensure that the design, safety, and operational guidelines cater to tanks that serve substantial needs in medical environments, distinguishing them from smaller or mobile storage options.

The other options do not align with the definition of a stationary tank. For example, a container designed for mobile installations is intended to be moved frequently, which contradicts the concept of being "stationary." A portable gas cylinder clearly refers to a smaller, easily transportable gas storage option, and a vessel used for temporary storage does not meet the criteria of being specifically designed as a stationary tank, especially concerning the capacity requirement.