The safety structure of complex process control systems is designed in multiple layers in order to ensure an equipment “event” is caught way before it starts.
This multi-tiered set up is based on Safety Instrumented Systems (SIS), which are the hardware and software controls on critical process systems. The SIS contains Safety Instrumented Functions (SIF), a specific control function used to achieve a Safety Integrity Level (SIL)—each of which is operating as a prevention method that is independent of any other method, otherwise know as Independent Protection Layers (IPL).
The availability of these layers of protection is crucial to the operation of a plant—and is mandated by industry regulations. The consequence of a failure because an alarm isn’t available, for example, can result in a critical safety event that can cost a lot or cause harm. As a result, companies spend a great deal of time and effort trying to measure and check the response times of SIFs.
The problem to date has been that IPLs are often managed using manual processes like spreadsheets, written procedures, process drawings, homegrown applications and even handwritten notes. This management process is not interoperable, not traceable and limited in functionality, which makes it problematic.
So problematic, as a matter of fact, that three of PAS Inc.’s clients in the oil and gas and energy industry asked the Houston-based company to solve the problem. And it did.
This week, the company introduced PAS IPL Assurance, software that provides real-time predictive analytics on the health and availability of SIS, alarm management systems and other IPLs. In addition to managing operational risk, IPL Assurance reduces compliance costs by automatically reporting on the SIS performance during a demand on the safety system.
“We had an opportunity to help clients automate safety instrumented system tests on one hand, and we can [also] capture information and report it automatically, which makes audits and reports easier,” said PAS CEO Eddie Habibi.
IPL Assurance pulls data from a variety of sources and brings in events to report on the functionality of IPL, making sure the system is available and is working with high integrity. It delivers analytics in a dashboard to identify when a function fails or exposing when a bypass could be a security risk, for example.
IPL Assurance is an extension of inBound which aggregates visualizes and validates operational boundaries (such as process alarms, safety instrumented trip points, mechanical design limits, normal operating zonesetc.) as part of part of the PAS PlantState suite—which is designed to improve overall operator situational awareness.
For its part, IPL Assurance provides the following analytics, alert, and visualization features:
• SIF performance management
• Testing and maintenance management
• Demand on safety system rate tracking
• Status of safety related alarms
• Safety system bypass management
• Safety and operational risk dashboard
Collectively, these features ensure the safety systems that manufacturers rely upon are available and the integrity of each system is reported. As a result, plant personnel can mitigate abnormal situations before they impact plant safety, reliability, and profitability.