Which container is specifically designed to store liquids or gases under pressure above 40 psi?

The cylinder is specifically designed to store liquids or gases under pressure above 40 psi. Cylinders are constructed from strong materials capable of withstanding high pressures and are often used for storing gases such as oxygen, acetylene, and other industrial gases. Their design includes features like pressure relief valves, which help ensure safe handling and storage under pressurized conditions.

Cylinders can be found in various sizes and configurations, but they all serve the common purpose of managing high-pressure environments. When gases are compressed into a cylinder, they occupy a smaller space, which allows for more efficient storage and transportation. This makes them essential in various industries, including medical, manufacturing, and energy sectors.

Other options like closed-head drums, carboys, and Dewar containers serve different purposes. Closed-head drums are primarily for storing solid and liquid materials but are not designed for high-pressure applications above 40 psi. Carboys are generally used for storing liquids, especially hazardous liquids, but they are not rated for high-pressure containment. Dewar containers are specialized for storing cryogenic liquids and are designed to maintain low temperatures, not necessarily for high-pressure applications. Thus, cylinders are the clear choice when it comes to safely containing pressurized liquids or gases.