Centenary blog: Spotlight on processes and safety

Centenary blog: Spotlight on processes and safety

1st June 2022

Every month throughout our centenary year, we will be asking an IChemE member to write a blog about each of the centenary themes. The themes have been selected to highlight and celebrate the enormous contribution that chemical engineering has made to society over the last century.

IChemE Fellow Ian Thomas, who was part of the editorial panel looking at processes and safety shared his choices of elements to celebrate, communicate and inspire.

Ian F Thomas, Principal, I F Thomas & Associates, Chemical, Safety & Environmental Engineers

Name: Ian F Thomas

Job title and organisation: Principal, I F Thomas & Associates, Chemical, Safety & Environmental Engineers

Bio: Ian gained a BSc in Chemical Engineering from Newcastle University; UK, an MEngSci in Environmental Engineering from Melbourne University in Australia; and a PhD in Applied Science - Alternative Fuels from RMIT University, Melbourne, Australia. Ian spent 25 years working in industry and 32 years to-date consulting in safety & environmental affairs, and more recently practicing as an expert witness.

IChemE role: Member of the Processes & Safety, Environment & Sustainability, and Energy editorial panels for the centenary.

The systems approach is, and will continue to be, a key skill for chemical and indeed all engineers in the future. It is engineers who develop the technology and scale-up of processes from laboratory-scale to industrial-scale, blossoming where possible as continuous production. Problems can, however, give process engineers the opportunity to apply chemical engineering principles and on-the-job learning.

Over the years, society has progressively become more concerned about risk and injury, often to the embarrassment of companies and even occasionally diminishing our ability to learn in familiar ways, such as in the school laboratory. While actual safety has improved as a consequence, a study of six hundred and sixteen accidents in the period 1920 to 2014* illustrated that accidents do keep happening. Safety will therefore remain important in the future, in particular in reducing the potential for low-frequency, high-consequence events which are abhorred by all of us.

The future chemical engineer will be dealing with complex problems, some of which we don’t yet even know about. Consequently, the processes of learning and training need to continually adjust. Traditional disciplines will remain, but our definition of chemistry will move progressively into the natural sciences and medicine therefore so must our engineering. Data analytics and digitalisation will be important, as will discussions on ethics, philosophy and communication.

Being asked by the centenary volunteer committee to select three elements from within the theme to celebrate, communicate and inspire was challenging given its many and varied inputs, but here I go …


  • We celebrate everything which chemical engineers do, apart from inventing, developing and propagating poisonous gases and chemical & nuclear weapons. For example, the development of process engineering to improve capacity, efficiency and profitability of industrial-scale plants for over 100 years; developing synthetic materials such as pharmaceuticals and plastics; and the production of some of the most ubiquitous materials in our daily lives.

  • We celebrate the development of hazard analysis techniques such as HAZOP (Hazard & Operability Study, QRA (Quantified Risk Assessment), LOPA (Layers of Protection Analysis), reducing risk As-low-as-reasonably-practicable (ALARP), Safety Management Systems (SMS), and even the likes of Mobil’s Operations Integrity Management System (OIMS).

  • We celebrate the evolution of design, optimisation, monitoring and operation of manufacturing processes of all types following the digital revolution; the transition from manual operation to pneumatic controllers, electronic distributed control systems (DCS) using micro-computers and wireless sensors; and the use of independent safety instrumented systems (SIS) allowing production capacities to be increased by orders of magnitude while reducing process risk to ‘tolerable’ levels.


  • Major accidents and loss of life continue to occur. Notable examples being Flixborough 1974, Seveso 1976, Bhopal 1984, Chernobyl 1986, Piper Alpha 1988, Coode Island 1991, Longford 1998, Buncefield 2005, Texas City 2005 and Deepwater Horizon 2010. Each accident has led to more action and commitment to improve safety. However, we must not relax as accidents continue to happen and recent examples include Lac Megantic 2013, Philadelphia Refinery 2019 and Pemex Refinery 2022. Important advances include goal-setting regulation pioneered by the UK Health & Safety at Work Act of 1974, the Seveso Directives of 1982, 1996 & 2012, the UK Control of Major Accident Hazards (CoMAH) legislation and the Victorian Major Hazard Facilities (MHF) regulations in Australia – all aimed at improving the safety of hazardous sites.

  • Chemical plants have always involved a combination of people and technology, human factors being at least equally as important as technological factors; this was only fully recognised in the early 1980s. The Seveso Directives were probably the catalyst that led to a more organised approach to human factors by IChemE and its member organisations. Human factors are now integrated into all aspects of process safety.

  • Inherently Safer Design (ISrD) is the first step in risk-based regulatory regimes, after which risks must be reduced to be As Low As Reasonably Practicable (ALARP) by passive, then active and finally procedural safety measures. In the UK, a demonstration of ALARP must be made to the regulator as part of a safety case in order for the proponent to be allowed to operate an installation. Eliminating or separating people from hazards is definitive, because it does not rely on reducing the estimated likelihood of events.


  • The risk analysis and mitigation tools that are now routine, e.g. Hazard and Operability study (HAZOP), were developed by pioneers Ken Gee and Trevor Kletz from Imperial Chemical Industries (ICI) in the 1960s and 70s. The concept of inherent safety was introduced by Trevor Kletz in his paper ‘What you don't have, can't leak’, following the Flixborough accident of 1974.

  • The world is facing its biggest challenge due to the impacts of increasing population and economies with consequences such as climate change, species extinctions and poverty in developing nations. To counter this, chemical engineering is well placed to deliver solutions, skills, and creativity to support an array of technologies to advance the health of the community and the planet. It is vital that knowledge of process and safety is shared with developing countries to meet this challenge.

  • The last 60 years have seen massive advances in safety in the process industries, many of which will be featured during the Institution’s centenary year. Whilst methods, tools, techniques and systems are important they are only part of the story. Advances can only be achieved by the co-ordinated efforts of people throughout an organisation; operators, technicians, engineers and managers. Many of these roles will be filled by chemical engineers. As part of ChemEng Evolution, IChemE’s Safety & Loss Prevention Special Interest Group is supporting the campaign, ‘Safety is my Job’, which is a collection of a variety of profiles of chemical engineers working in safety-related roles.

I encourage you to visit the Processes and Safety section of the ChemEng Evolution website to find out more.

A processes and safety panel discussion entitled “Safer processes for a sustainable world” was held on 8 June 2022. Watch the recording here. For more information on IChemE's centenary, visit www.chemengevolution.org or follow #ChemEngEvolution on social media.  


1. Preventing major accidents by the use of high flashpoint fuels, Thomas I F, Porter N A, Lappas P;  proceedings of the conference Hazards Australasia, Institution of Chemical Engineers, Melbourne, 23-24 November 2016

2. An assessment of the technical and economic feasibility of using vegetable oil fuels in compression ignition engines, with comments on more fundamental ways to offset the impending post fossil fuel dilemma, Thomas I F, School of Science, College of Science, Engineering and Health, RMIT University September 2016