Field Instrumentation—The First Line of Defense

The process control system and safety instrumented system (SIS) both depend on field instrumentation to monitor process conditions. Modern sensors are highly sophisticated and very reliable.

When used in the context of a well thought out system, they watch for subtle changes in conditions that are precursors to larger incidents. When temperatures or pressures begin to exceed acceptable levels, they are the first to report developing problems.

Reliability is paramount because those instruments have to perform their function when called upon. In a stable operating environment, some safety-related devices may wait for months or even years for an emergency situation, and they must do their job as expected.

Careful design and testing has to work hand-in-hand with a critical maintenance program to ensure reliability.



Making sure that your plant’s safety instrumented systems are prepared to respond is a lot like
maintaining athletic fitness.
While Layers of Protection should remain functionally independent from each other, it’s also important streamline the management of process safety.
Maintenance activities at Carbide Industries couldn’t keep pace with equipment deterioration. The failure was ultimately catastr…