What is the benefit of including pressure-relief devices in tank designs according to API 650?

• A. They are cost-effective alternatives
• B. They improve the aesthetic appeal of tanks
• C. They enhance safety by controlling internal pressure
• D. They reduce the need for inspections

Answer: (C)

Including pressure-relief devices in tank designs according to API 650 is crucial because they enhance safety by controlling internal pressure. When fluids such as oil and other volatile substances are stored in tanks, they can generate vapors and increase internal pressure as temperature changes or if a blockage occurs. Pressure-relief devices are specifically designed to alleviate excessive pressure buildup, thereby preventing potential failures such as tank rupture or explosive incidents.

By maintaining the internal pressure within safe limits, these devices protect both the tank structure and the environment, reducing the likelihood of leaks and spills that can occur from overpressure situations. This safety feature is essential not only for the integrity of the storage system but also for the safety of personnel and surrounding communities.

Other options like cost-effectiveness and aesthetic appeal do not address the primary purpose of pressure-relief devices, which is fundamentally centered on safety and risk mitigation. While it's essential to consider cost and inspections, the core functionality of these devices is precisely about managing internal pressure to safeguard against catastrophic failures.