Guest blog by David Hatch from Process Safety Integrity (PSI)

Every business has legal, economic, and ethical objectives that range from mandatory safety to commercial goals to corporate citizenship. Businesses undertake a certain amount of risk to achieve these objectives. In this blog, David Hatch (Process Hazard Analyst at Process Safety Integrity) gives a brief introduction to a recent article on barrier-based risk management that was published in the Pharmaceutical Engineering magazine.

Risk and reward

The Life Science industries (Pharmaceuticals, Biotechnology, Medical Devices etc), in order to achieve their commercial expectations, have regulatory obligations to produce products that are safe for patients without harm to personnel or determent to the environment. In carrying out these activities, they accept a certain amount of risk which ICH Q9 defines as “the combination of the probability of occurrence of harm and the severity of that harm” and defines harm as “damage to health, including the damage that can occur from loss of product quality or availability” ISO 31000 offers a broader definition of risk as the “effect of uncertainty on objectives”.

Risk is therefore not limited to mandatory SHEQ concerns but also includes asset integrity (equipment repair or replacement) and reputational status (shareholders, media & customers). Risk (objective) management is an ongoing challenge and the bowtie technique can be used to visualize, assess and control all these separate (but often related) risks.

Barrier based risk management

Bowties offer a simple but effective visual representation of the potential Threats that a business must prevent and the associated Consequences they have to mitigate. These diagrams provided a clarity and consistency that makes risk understandable (at all levels) and therefore easier to monitor and manage. Risk management is underpinned by Barriers which are organizational and technical measures based on Active, Passive & Continuous Hardware either independent from or in conjunction with Human action or response.

Bowties can help companies efficiently capture their threats and communicate the criticality and effectiveness of the barriers that provide the necessary resistance and resilience to achieve and sustain compliant operations.


The simple diagrammatic representation of a process or plant provides an effective, transferrable platform for knowledge that passes from the designers to those who build, operate, maintain, and monitor these facilities. This knowledge is challenged by a series of qualification activities at key stages.

  • Design Qualification (DQ): Does the proposed design of the barrier meet the intended purpose?
  • Installation Qualification (IQ): Has the barrier been installed correctly?
  • Operational Qualification (OQ): Is the barrier capable of operating within established limits?
  • Performance Qualification (PQ): Does the barrier perform effectively and reproducibly?

These physical, functional, and procedural barriers can also be applied to change management in which people adapt, processes or plants are modified, and the effects of change must be evaluated and addressed. Ongoing assurance that the barriers are still present (IQ) and performing (OQ/PQ) can be confirmed by regular inspection and auditing (planned demands) as well as learning from incidents (unplanned demands), with the results shown (or suitably summarized) to highlight vulnerabilities.

Read more about bowtie analysis and barrier based risk management in life science industries

To help understand how BowTieXP and other applications can help to you to know, show and grow the effectiveness of your barriers, we invite you to read the full article series (5 parts) by David Hatch which is available here, on the ISPE iSpeak Blog.

© David Hatch – Process Safety Integrity. 2018– The copyright of the content of this guest blog belongs to David Hatch who has authorized CGE Risk Management Solutions B.V. to provide this content on its website.