Designing a Control Strategy for Facilities with Single-Use Systems

For small- and mid-size biologic producers that are incorporating single-use systems in their manufacturing facility, choosing the right process control system is one of the most critical decisions they make when building a facility. Integrated production processes and information-driven operations are needed to ease compliance, reduce batch cycle times, and get to market faster.

Traditional, large, and monolithic distributed control systems (DCS) can deliver these capabilities; however, they often aren’t flexible enough to meet production needs for smaller-volume processes using single-use equipment and systems.

Equipment-level automation is also not an ideal option. This approach, where each unit operation has a dedicated control system and user interface, creates challenges such as islands of automation that complicate centralized data collection and user account management for the system administrator.

A better approach to automation is to build for the future with a scalable and flexible system that allows producers to incorporate flexible “plug-and-play” equipment. A modern DCS uses modern technology (e.g., industrial ethernet, faster controllers, scalable distributed software) and practices (e.g., cyber-security standards) to make the system more scalable, flexible, and secure. Using flexible systems creates the ability to evolve operations over time, meet regulatory requirements, reduce validation effort, and lay the foundation for newer digital technologies and analytics—all of which can be accomplished with a lower total cost of ownership.

The challenge is making the right choices for this control system early in the process of building a new facility with single-use equipment, because those choices will reverberate and have consequences across the life of the facility. For this reason, producers should make sure to consider the following areas when designing a facility.

Network infrastructure

A good starting point for designing a control system is the network infrastructure. Producers should consider how a facility’s communications backbone will meet current needs with simplified connections and seamless data access, while providing the flexibility and scalability needed to accommodate future operational and technology changes.

Legacy fieldbus network protocols used in many pharmaceutical plants today can create challenges in a single-use facility. For example, data limitations can restrict a producer’s ability to get valuable diagnostic data from devices and instrumentation. Legacy fieldbus can also be harder to maintain and scale if the network infrastructure needs to change to support new technologies over time due to their inflexible nature.

A modern industrial network protocol, such as EtherNet/IP, does not have these limitations. On EtherNet/IP, single-use equipment and instrumentation can be easily configured to communicate with and publish rich diagnostic data to the process control system. This communication builds into scalable plant-wide ethernet architectures through switches and other network devices. This “plug-and-play” connectivity creates a simpler plant infrastructure, with only power and ethernet cabling required to connect unit operations, and allows for ease of expansion and easier equipment change-out.

Operational flexibility

Automation may not be on a producer’s mind when developing a new biologic or while in the early stages of clinical trials. It’s never too early to be thinking about automation, because the optimal automation set up can provide significant operational flexibility and greatly reduce the effort involved in tech transfer.

Take the example of a start-up biologic company that invests in single-use equipment with a modern DCS. The equipment can be flexibly assembled into a process train and run manually during early process development, which allows settings to be changed as the process is being fully developed.

Once the company is ready to produce at a commercial scale, the equipment can be easily configured to run repeatable recipes with no major software updates, because the recipe is assembled from the same manual phases run in development. The equipment can even revert to manual operation if an issue arises where intervention is required.

Additionally, equipment can be repurposed and used in a different process because each individual piece of equipment has a full set of functionalities, essentially making each component a replaceable part.

Technology standardization

The more that customized technology and functionality is designed into a single-use facility, the more that specialized knowledge is required for design, operation, and maintenance activities. This requirement for specialized knowledge should prompt producers to establish and leverage standards as much as possible.

Standards such as the International Society of Automation’s (ISA) ISA-88 (1), ISA-18.2 (2), and ISA-101 (3) help create a consistent design approach across multiple pieces of equipment for functions, including procedural control, alarm management, and human-machine interface (HMI) style. These standards can be easily enabled when configuring modern control systems using commercial off-the-shelf software libraires. By using these class-based libraries, equipment vendors can create application-specific software with less time and development cost. These libraries also smooth the way for those who inherit equipment—such as validation teams, process engineers, and support technicians—because the software is lower risk, provides consistent information, and is easy to maintain.

The libraries also include standard data structures for specific classes of devices, such as pumps, valves, and others. These data structures provide the basis of constructing analytics for equipment, helping producers increase process performance or equipment uptime in the long run.

The operator experience

The user experience of operations staff is too often left out of automation projects. But producers should consider prioritizing the user experience of the control system if they want to create a more efficient workforce. Libraries of reusable class-based objects can be used to create a common user interface style for staff, for instance. For example, a valve will look and feel the same on a tangential flow filtration skid as it does a bioreactor.

Producers should also ensure their visualization system leverages industry standards, such as ISA 101 (3). The standard can help draw operators’ attention to adverse process conditions to help make sure these conditions are seen and dealt with quickly.

Disruptive technologies

New technologies are changing how people work in a single-use facility—perhaps none more so than augmented reality (AR). How can producers apply technology such as AR in a meaningful way in facilities? The best way to find out is for automation engineers to meet with process engineering and operations teams to discuss needs and potential risks that the technology can address.

For example, single-use consumables can require operators to make hundreds of sanitary and aseptic connections during setup. One wrong connection can lead to a costly batch loss. By performing this work in an AR environment, an operator can confirm each connection and reduce the potential for mistakes.

In another scenario, production operators may not have a view of an HMI when they are performing activities such as pumping media, which can result in missing critical alarm notifications. It may be beneficial for operators to wear an AR headset while doing this work so they are more likely to see alarms as they happen.

Cybersecurity

Mitigating cybersecurity risks is a priority for most biologics producers today. A robust cybersecurity approach can help producers protect their sensitive regulatory and process data, while realizing the many benefits of digitalized operations.

Part of this approach involves designing a control system with standards like ISA/International Electrotechnical Commission (IEC) 62443 (4), which is a consensus-based cybersecurity standard for automation. The standard establishes that multiple layers of protection will provide the most redundancy in case a specific security layer fails. This concept is referred to as a defense-in-depth strategy and spans personnel knowledge and awareness, physical security, application, and device security. Some control systems are now certified to this standard.

Common Industrial Protocol (CIP) security-enabled control devices offer another layer of protection. CIP Security is an extension to the CIP from the automation industry association, ODVA. It uses data authenticity, integrity, and confidentiality to protect against attacks on industrial communications. Industrial asset-management software can also provide recovery and automatic back-up capabilities that are critical following a security incident.

Easing the journey to commercial production

A modern, scalable, and flexible control system offers a pragmatic approach to developing an automated single-use facility. With the right design choices, this architecture can help producers create a connected, information-driven facility that scales and evolves with their business.

References

1. ISA, ANSI/ISA-88.01-1995 Batch Control Models and Terminology (Research Triangle Park, NC, 1995).
2. ISA, ANSI/ISA-18.2 Management of Alarm Systems for the Process Industries (Research Triangle Park, NC, 2016).
3. ISA, ANSI/ISA 101.01 Human-Machine Interfaces for Process Automation Systems (Research Triangle Park, NC, 2015).
4. ISA, IEC 62443 Industrial communication networks–Network and system security series.

About the authors

John Hatzis is a global Life Sciences industry consultant, at Rockwell Automation, and Peter Genest is a business development and strategic partnerships leader at Cytiva.

Article details

BioPharm International
Vol. 34, No. 10
October 2021
Pages: 32–35

Citation

When referring to this article, please cite it as J. Hatzis and P. Genest, “Designing a Control Strategy for Facilities with Single-Use Systems,” BioPharm International, 34 (10) 2021.