As you already know, there are a multitude of pressure relief valves out there. In the industry, we tend to use terms like safety valve and relief valve interchangeably. And for the most part, this makes sense. Most pressure relief valves are designed to do the same thing — release pressure in a system.

But is there a difference between some of these commonly used terms, and if so, what does it mean for you? Here’s a quick breakdown of two popular terms: safety valve vs. relief valve.

Safety Valve vs. Relief Valve: Is There a Difference?

While both terms refer to valves used to release pressure from a pressurized system, their technical definitions are a bit different. In general, the term relief valve refers to a valve within a pressurized system that is used to control pressure for the optimal functionality of the system. Relief valves are designed to help your facility avoid system failures, and protect equipment from overpressurized conditions.

The term safety valve, on the other hand, refers to pressure valves that are designed to protect people, property, and processes. In other words, the term safety valve refers to a failsafe, last resort valve that will release pressure to prevent a catastrophe, usually in the event that all other relief valves have failed to adequately control pressure within a system.

Do Safety and Relief Valves Do the Same Thing?

The general purpose of both safety valves and relief valves are the same. Both are pressure relief valves, and they are designed to let off pressure in any situation where a system becomes overpressurized. That said, relief valves and safety valves do function slightly differently:

  • Relief Valves are designed to control pressure in a system, most often in fluid or compressed air systems. These valves open in proportion to the increase in system pressure. This means they don’t fly all the way open when the system is slightly overpressure. Instead, they open gradually, allowing the system to return to the preset pressure level. When that level is reached, the valve shuts again.
  • Safety Valves are used for one reason — safety. Instead of controlling the pressure in a system, they’re designed to immediately release pressure in the event of an emergency or system failure. Unlike relief valves, safety valves open immediately and completely to avoid a disaster, rather than to control the pressure of a system.

While both safety valves and relief valves work to release excess pressure, the way they go about it is a little different. Check out this table, courtesy of Difference Between, for a little more information about the differences between the two valves:

Can I Use Safety Valve and Relief Valve Interchangeably?

Now that we have a better understanding of the technical definitions of both terms, you might be wondering if it’s alright to continue using the terms interchangeably. In most cases, industry technicians will understand what you’re talking about no matter which term you’re using.

If you’re working on testing both types of valves, it’s important to understand the difference between these valves, just so you know your facility is adhering to the proper testing schedule. Otherwise, you shouldn’t have to worry too much about the exact terminology. Both safety and relief valves are types of pressure relief valves, they’re just implemented a bit differently.

Whether you’re working with safety valves or relief valves, they’re going to need testing. Minimize downtime this year with AccuTEST’s high-tech pressure relief valve testing system. Offering real-time results and remote support, our testing system can be used inline to test any types of pressure relief valve. For more information about our system, or for a free live webinar demo of the AccuTEST system in action, contact us today.

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