What is the value of a life?
COVID has forced us all to reason about the risk of death. But, what long-term impact might the pandemic have on the professionals who have always had to do so?
Risk appetite
The COVID pandemic has forced us all to weigh the risk of death against the impact of measures to prevent it. We have all discovered our appetites for risk as they have become manifest in the decisions we’ve taken: Did you get jabbed? Did you wear a face mask? Or did you attend a ‘bring your own booze’ party during lockdown?
Some of us are professionally required to reason in this domain. There is no such thing as zero risk and the safety engineer’s raison d’etre is to effectively balance risks and outcomes to enable technological benefit.
After joining the Rail Safety and Standards Board in the 2000s, I drafted the first version of UK rail industry policy in this area - ‘Taking Safe Decisions’. The conundrum for the railway at the time was how to agree our risk appetite in the aftermath of a flurry of devastating rail accidents, including Hatfield, Potters Bar and Ladbroke Grove. The government and industry were viscerally aware of the related risks - actual, commerical and reputational - and decisions like whether or not to fit new train signalling and braking systems were a matter of national debate.
Ultimately, to formulate the policy, we went back to the case law. Way back in 1949, in the case of ‘Edwards Versus the National Coal Board’, Judge Asquith ruled that those considering safety measures had to implement them unless the ‘costs’ of doing so were grossly disprortionate to the ‘safety risk’. In the extreme, the ‘safety risk’ means the chance of a person’s death.
The first challenge was always: how can you put a value on life? This was taboo to many. But in our rail work I quickly found that engineers are generally even more pragmatic than scientists about such matters. An important point to consider is that reasoning about such risk is ‘a priori’, i.e. distinct from any events that have actually occurred. There is also a range of possible future situations that might occur at the time the decision is made; to use a modern science fiction term, there is a multiverse of potential futures. So we are never talking about the value of any particular individual’s life. Instead, we are creating some rules we can all agree on to reach a difficult, uncertain decision together.
The economic value
According to Judge Asquith, the ‘cost’ is made up of the “time, trouble and effort” that measures lead to. This reminds me of Charles Darwin’s quote that:
A person who dares to waste one hour of time has not discovered the value of life.
The statistical value used in the UK for averting a transport related fatality - the ‘Value of Preventing a Fatality’ or VPF - is approximately £2 million. Similar amounts are used in other sectors. The VPF increases with GDP per capita, which of course varies over time and significantly across the world.
I remember many years ago showing a complicated risk model that I had built to a visiting research student from Pakistan. At best, the model offered the prospect of shaving a tiny fraction of risk from the 0.734 fatalities per year, statistically assessed to relate to the risk of train derailments on the British rail network. The researcher thought that the model was ‘fascinating.’
“Do you do anything like this?” I asked.
“No,” she replied, with a matter of fact shake of the head, “that would be a luxury.”
How much life do you have?
The rail industry’s use of the VPF was strongly criticised by Professor Philip Thomas of Bristol University at the time of the launch of ‘Taking Safe Decisions.’ Professor Thomas had an alternative approach - J-Values - which balanced safety expenditure against the extension of life-expectancy brought about by safety measures. In this approach, averting a fatality to a child weighed more heavily in the balance of risk than averting a fatality to a senior citizen, for example. For many people there is logic to this approach and there is much to commend the technique’s accuracy and rigour: precision in risk assessment can help to optimise decision making, particularly in a data rich environment.
However, this level of granularity did not naturally fit with the sorts of decisions made on the railways. What was also missed in Prof Thomas’ critique was that the British rail industry had just spent several years building awareness, competence and buy-in to an enhanced version of the traditional VPF approach. The approach was already socialised and bedded into the industry. The pragmatic, ‘engineer’ view was that reasoning about risk would never be an exact science, particularly when considering rare, catastrophic events like train accidents. The most important thing was to have an agreed method so that we could roll our sleeves up and tackle a backlog of difficult decisions.
Maintaining our tools
So perhaps that’s the answer. The reason why we put a ‘value on a life’ is because we really care about it and we want to make the right decisions at the right time. Wariness of discussing taboo issues can lead to inaction and a worse outcome in terms of cost and safety for everyone. COVID has taught us all a little more about the need to consider such things and brought broader awareness and familiarity.
But what will the blowback of new realities be to longstanding approaches to safety decision making? COVID has had a very heavy global toll with over 5.5 million deaths recorded at the time of writing. Might this - consciously or unconsciously - soften our focus? It has also had a devastating impact on GDP globally: how might this impact the setting of the VPF and the culture that surrounds it’s use? Should theoretical accuracy prevail? Or should we ensure that we fight hard against any subtle weakening of criteria, in recognition that the VPF is an engineer’s tool to deal with emergent risks?
Commenting
Please do feed back your thoughts in the comments, on linkedin or on Twitter.
In addition to bringing back memories of a great project with a talented team, writing this post has reminded me that a paper I wrote on the subject of the VPF many years ago has just been republished in a 30 year compendium of the work of the Safety Critical System’s Club: the Club has put a lot of work into the production of this book and I would highly recommend it to you, particularly if you’re a safety professional.
The next issue
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Thanks for reading
All views are my own and I reserve the right to change my opinion (particularly when readers inform me of things of which I was unaware!).
If you’re interested in any advice, guidance or collaboration on any of the topics raised please feel free to drop me an e-mail on george.bearfield@ntlworld.com: My particular area of professional and research interest is practical risk and assurance of new technology. I’m always keen to engage on interesting projects in this area.
The image used on social media is "The Howe Scale. (front)" by Boston Public Library and is licensed under CC BY 2.0
And finally, many thanks as always to my rigorous editor, Nicola Gray.