Another Silo Down: How Integrated SIS Transforms Process Safety

Summary

The shift from disparate, siloed control systems to integrated automation architectures has transformed process operations. In particular, it’s helped operations be more productive and efficient with smarter and simpler equipment, faster configuration and commissioning times, and more connected employees. Now, one more silo is coming down with the introduction of integrated safety instrumented systems (SIS).
Integrated SIS unites safety and process control onto a common platform. This not only puts an end to the SIS as an outsider from the rest of an automation architecture–it helps simplify work across the life of process equipment.

With integrated SIS, specialized expertise in both safety and process control is no longer needed to configure and commission equipment. More standardized equipment can be deployed in process environments to ease the jobs of operators and technicians. And insights into equipment health and performance can be more easily delivered or even expanded upon.

Simplifying and modernizing process safety

Industrial control systems have been evolving for decades to take on more of the various types of controls used in production environments, like process, batch, discrete and motion control. Integrated SIS is the latest step in this journey.

Now, the critical SIS that process operators depend on to protect against industrial hazards no longer needs to be designed, implemented and maintained in isolation from the base process control system (BPCS). This integration of safety and process control expands how an integrated automation architecture can boost efficiency and productivity in several ways. The three areas where companies will likely see the biggest benefits from using integrated SIS are:

1. Faster, less complex deployments

Historically, engineers have needed to program and configure SIS and BPCS separately, using different tools and logic.

With integrated SIS, engineers only need to learn one toolset to program and configure the SIS and BPCS. It doesn’t matter whether they’re building a process or safety loop, the mechanics are the same. And because the environment within the toolset looks and feels the same whether an engineer is working on the SIS or BPCS, configuration is simplified and engineering time can be reduced. This simplification also carries over to the on-site deployment of equipment for simpler and faster commissioning.

Additionally, engineers can extend the latest productivity-enhancing features in the design and configuration tool that they use for BPCS controls to the SIS controls. With multi-user collaboration features, for instance, multiple engineers with varying skillsets and who are in different locations all can work on the same project simultaneously. And granular safety signatures, which compartmentalize safety functions, can reduce SIS validation and testing times.

Integrated SIS solutions can also reduce engineering time with built-in safety functionalities. Instead of creating custom add-on instructions for safety configurations to achieve SIL 2, for instance, engineers can now simply check some boxes to select and apply pre-built safety configurations to their project.
 

2. More seamlessly delivered insights

Breaking down silos and bringing together data from disparate systems in an integrated architecture can ease access to insights in process equipment–or open doors to new insights.

Just consider what being able to correlate production and energy data has done for companies. It’s allowed them to link production output to energy usage and uncover opportunities for optimization. And it’s created new ways to identify underlying issues, like if equipment is working harder than usual and in need of maintenance.
Bringing SIS and BPCS data together in an integrated architecture creates similar opportunities for accessing insights. For example, it can simplify the development of HMI displays.

In a process environment, operators want to know what’s happening regardless of whether insights come from SIS or BPCS data. But creating a common HMI display can be a complex task when it involves mapping data from disparate systems that use different logic. Creating a common display is easier and more intuitive when BPCS and SIS data come from the same platform and are based on a common logic.

There may also be opportunities to combine SIS and BPCS data to give process operators and technicians new insights and help them be more proactive in preventing SIS-related shutdowns. What if they could visually monitor, for instance, how close a process is to the point where the SIS needs to take over? They may be able to act to avoid shutdowns and the often long and costly restarts that come with them.
 

3. Simplified operations and maintenance

Easing the jobs of employees in process environments is becoming critical given the industry’s workforce challenges. About two-thirds of respondents in a recent survey of manufacturers said attracting and retaining talent is a primary business challenge.

Just like a common platform for SIS and BPCS simplifies design and configuration work for engineers, it also eases operations and maintenance activities for end users. Now, instead of learning how to use and maintain separate hardware and software for their SIS and BPCS, they can learn just one common hardware and software for both systems.

Maintenance can also be further streamlined because spares only need to be stocked for one platform instead of two. And if a technician has questions or needs support for their SIS or BPCS, they only need to contact one vendor. This also eliminates the finger-pointing between two vendors that can happen when there’s an issue between the SIS and BPCS.

Integrated SIS solutions can also bring added value to process environments by offering newer, more modernized capabilities than traditional SIS platforms. The controllers used in a new integrated SIS solution, for example, can offer more memory. They’re also available in options that are designed to be resistant to corrosive gas environments.

By using a redundancy system update feature, an integrated SIS can also avoid downtime during updates. The hardware and software for the solution’s controller, communication modules and redundancy modules all can be updated while they’re running.
 

Target use cases

Because integrated SIS solutions are just in their infancy, they’re not yet available for all process safety applications. The solutions have the certifications–including IEC 61508, IEC 61511, IEC 62061 and ISO 13849–that engineers look for to support a wide variety of applications. However, integrated SIS solutions don’t yet support applications that require redundant safety I/O.

So, where should an integrated SIS solution be used?

It can be a good fit for general process safety applications, like those found in oil and gas operations. And it
can be used in process safety applications where simplex I/O is needed for non-critical functions, like lamps, horns and safety gates used around a machine.

It’s also a good fit for hybrid applications, where both machine and process safety are required. It can support applications where shutdown avoidance is critical and I/O availability is not a priority. And while an integrated SIS solution isn’t intended to directly control robot lines, it can be used for multi-zone control of robot lines that use machine safety, where each zone can be shut down independently.

Applications like tunnels, transportation and baggage-handling systems where simplex I/O is used for non-critical systems and simplex safety I/O is wired with relays for potential I/O failure can benefit from using an integrated SIS solution. Entertainment applications that require controller redundancy for availability and simplex safety I/O for fail-safe applications are also a good fit for the technology.

As integrated SIS solutions continue to grow and evolve, such as with the addition of redundant I/O, they will take on a wider range of applications.
 

A new era in process safety

By bringing process safety onto the same platform used for process control, companies can achieve new levels of efficiency and productivity across the lifecycle of process equipment while continuing to keep people and assets safe. Integrated SIS can also increase visibility into process operations and enable more proactive decision making for both operations and maintenance teams, making more reliable and potentially safer process operations possible.