This video, produced by the BARPI, presents an actual accident that occurred inside a French chemical plant in 2012. This media offers a better pedagogical approach for understanding the accident context and its causes than paper documents.
Pedagogical interests of this video are the following:
For a non specialist audience, it is instructive by illustrating the reality of technological hazards in modern industrial plants and how risk is managed. Given the high toxicity of the chemical substance fabricated, the unit involved was designed under the so called “defence in depth” principle and therefore has several passive or active technical layers of protection. On the day of the accident, these layers prevented a major accident that might have resulted from a toxic release near urbanized areas.
For a specialist audience, this video illustrates several important aspects for industrial safety:
– the role of human error in real accidents: here a human decision led to the bypassing of one of the layers of protection and aggravated the accident. It illustrates the limit of the “defence in depth” concept by remembering us that safety takes place in a technical but also human context.
– the influence of work context on operators: during an abnormal situation, the display of a false information parameter is sufficient to strengthen the misperception born in the mind of the control room operators (also known as ‘anchoring’ or ‘tunnel-vision’) and leads them to take a dangerous decision. This type of cognitive error has already been identified in the nuclear accident of Three mile island in 1979, and closer to us, in the crash of the commercial French airliner flying from Rio to Paris in 2009.
Note: this aspect was also developed in the following accidents analysis related to industrial automation (available for download on our website):
- Are sensors compliant with safety ? (SY_sensors_2012.pdf)
- Processing function ; hazards in the control room (SY_processing_function_2013.pdf)
– the complexity of actual accident: the scenarios of actual accidents are sometimes very different from those identified in previous risk analysis. Therefore, safety also builds on adaptability of people and organisation in charge of it.
For pedagogical purposes, a high-definition version of this video (780 Mo) can be sent on request, please contact us on the following mailbox: firstname.lastname@example.org