Which of the following is employed as a safeguard against hazards associated with flow?

The use of a check valve as a safeguard against hazards associated with flow is grounded in its primary function, which is to prevent the backflow of fluids in a piping system. When a fluid is moving in one direction, the check valve allows it to pass through. However, if there is any attempt for the fluid to flow backwards—either due to a drop in pressure or a change in the flow direction—the check valve automatically closes to prevent this reversal. This is crucial in maintaining the integrity of the system, preventing potential spills, leaks, and contamination that could occur if hazardous materials were allowed to flow backward.

Additionally, check valves help protect equipment downstream from undesirable flow conditions, thereby ensuring the consistent and safe operation of a process. This is particularly vital in systems handling chemicals or other hazardous materials, where backflow could lead to serious safety and environmental concerns.

While other options, such as chemical containment, safety relieves, and pressure gauges, do play important roles in overall safety and process management, they do not specifically control the direction of flow in relation to preventing backflow hazards. Instead, they serve different purposes such as managing pressure, monitoring conditions, or containing spills, which are also essential but do not address the direct need for preventing backflow that