Safety is not _the_ priority...

- english gareth lock human factors safety Apr 14, 2018

This might be surprising for many, but safety is not the priority which organisations and individuals have to consider when diving. Both organisations and individuals have to balance a number of other priorities including time, money, reward, resource, productivity, results, fear of litigation and legislation all within a context which is not static, but rather is dynamic and evolving.

What does ‘safety’ mean anyway?

The International Civil Aviation Organisation (the international regulatory body responsible for aviation safety) has defined safety as “The state in which the risk of harm to persons or of property damage is reduced to, and maintained at or below, an acceptable level through a continuing process of hazard identification and risk management” in their ICAO Safety Management Manual. The bolding is mine to highlight that there is a need to understand what an acceptable level of risk actually is.

So how do you define ‘risk’?

In 1983 the Royal Society tried to define it after years of study and came up with the following in their report 'Risk Assessment' “...the probability that a particular adverse event occurs during a stated period of time, or results from a particular challenge. As a probability in the sense of statistical theory, risk obeys all the formal laws of combining probabilities.” Unfortunately, according to John Adams in his book 'Risk', almost immediately after the report was published, the Royal Society realised that this definition was flawed because it does not obey the laws of probabilities and is very much context dependent. An example given in Adams’ book highlights this nicely and the concept can easily be carried over to diving. Ice on a sloping pavement allows kids to create a slide and provides an opportunity for great fun. However, the same patch of ice could be lethal to a frail old person if they slipped and fell and broke their hip. As such, the same hazard can provide both a negative outcome or a positive opportunity depending on the context and it is these relationships and the context which are so important to understand when looking at acceptable risk and safety.

What does acceptable mean?

Research and practice in established high-risk domains use the term As Low As Reasonably Practicable (ALARP) as a way of helping to define what acceptable means. The principle assumes that there is a level of risk which is tolerable and requires that the risk is at least below that level. Crucially this means that someone or organisation has to define a tolerable level. In diving, we often look for zero fatalities as the tolerable level, but that is not possible given the almost infinite combination of factors which could lead to a fatality. I am not sure there is a definition anywhere published which is considered tolerable or even acceptable. The qualifying term "reasonably practicable" in ALARP determines how ‘low’ risks should be pushed towards the region of negligible risks but for this to happen, there needs to be data which can be used for this purpose which looks at both severity and likelihood. Unfortunately, the majority of incident reporting data in the diving domain is not fit for this purpose and to talk about interventions being successful is likely flawed without much more accurate rate data.

Notwithstanding the lack of data in the diving domain, you could make an assumption that with an infinite amount of effort you could reduce the risk to an infinitely low level, but at the same time, an infinite amount of effort will be infinitely expensive to implement the intervention! So ALARP assumes that there is a risk level which is so low that "it is not worth the cost" to reduce it further. In essence, this means that risk reduction measures should be implemented until no further risk reduction is possible without very significant capital investment or other resources expenditure that would be grossly disproportionate to the amount of risk reduction achieved. Of note, ALARP can only be demonstrated if the risk is properly assessed, understood and the results are used to determine controls.

So how does ‘safety’ work in the real world and why isn’t safety the priority?

Diver training organisations are businesses. As such, they have requirements to meet in terms of staying solvent and keeping their shareholders, boards and directors happy. This means they have to manage financial, productivity, reputational and safety risks, and balancing them against each other. The same goes for diving equipment manufacturers developing and releasing their products. One area to consider when looking at equipment manufacturers is that CCRs. The level of expenditure and investment is massive for both design, testing and insurance and this needs to be balanced to what is ALARP, especially considering what the consumer market will sustain given its pretty small size. 

One way to visualise this is by thinking about a set of scales with safety on one side and productivity on the other. If you increase the pressure on the productivity side (become more productive), the safety arm will move the opposite way. Depending on the flexibility of the material of the arm, there can be some bending, but if you push it too far, the arm will snap.

Now consider money and safety? The same process and problems are faced. What about when time is limited and the same level of ‘safety’ has to be maintained? What gives? These are all trade-offs and Erik Hollnagel has written extensively on this as part of this work on Efficiency-Thoroughness Trade-Off.

However, as outside observers to the system, when we see diving accidents it is easy to jump on the training organisations and blame them, as that is an easy thing to do. As humans, we are efficient (lazy!) and want to find a quick and easy solution to the problems we face. However, safety is not a simple problem, it is complex, especially when considering global operations. As Nancy Leveson said, “Safety is a system property not a component property” and in the context of diving, this means a manufacturer can't make a safe rebreather or an instructor can't make a safe diver, they need to be considered in the context of the environment. You cannot solve complex problems with simple solutions, you need to look at the system as a whole if you want to improve safety.

Diver training organisations insulate themselves from what happens in dive centres and dive schools through the use of adherence to training standards (but see Work As Imagined/Work As Done for potential issues), liability waiver forms and ‘air gaps’ between the client and the training organisation. Consequently, this fine balancing act is carried out by the local dive centres and schools who are competing for what appears to be an ever decreasing pool of clients/students. On one side is the number of certifications and students coming into the business (productivity) and on the other side is 'safety’. Given the need to balance requirements, and the lack of any robust oversight and quantifiable data to meet an ALARP requirement, the term ‘acceptable’ should be seen as dynamic. However, I am sure the lawyers would have a different view. As Sidney Dekker has said, it isn't so much where the red line is drawn in between error and violation in a culpability model, but rather who draws the line.


Unfortunately, the only time when it is really possible to see that the balance has gone wrong is when an accident happens. However, even then ‘safety’ can still be maintained and this is shown by a comment made by one of the insurance panel at DEMA in 2016 who stated that ‘as long as your paperwork is in place, then you will be safe’ inferring that the instructors/centre would be safe from litigation rather than operationally safe.

What about ‘safety’ and individual divers?

Divers have these same balances and trade-offs. They don’t have an infinite amount of time, nor do they have bottomless pockets filled with money. In fact, I would argue that many divers are more time-poor than money-poor. This means that when time is limited, they will trade-off safety against the opportunity to go diving. And whilst it is easy to say from the comfort of your armchair “the reef/wreck/target will always be there” if you haven’t dived for a while and won’t be diving for a while, then it is easy to take the risk, especially if things haven’t gone wrong in the past or if the community doesn’t talk about the near misses that have happened. (We have lots of biases which impact our decision making and this blog just covers a few of them.)

Another point to consider is that the same attitude towards risk and safety for diving itself also exists when it comes to changing or servicing diving equipment but I would argue that this is more likely to be money-related rather than time-related.

What should I take away from this article?

When things go wrong, it is very unlikely to have been a single, catastrophic event which was unseeable by those taking part in the dive. (Just because it is there, it doesn't mean you can see it - attention blindness). There are very few adverse events which could not have been prevented in diving, the difficulty is determining what is an acceptable level of investment required to predict, prevent or mitigate the risk if you don’t know the likelihood or the severity of the risk materialising. Importantly, that investment covers cognitive resources as well as and physical resources such as time and money, and so if we don't go looking for issues whilst diving or researching adverse events to learn from them, we are being cognitively efficient.

If we are using fatalities as the metric of ‘safety’, then diving is pretty safe in statistical terms even if we use the poor data that we currently have. That doesn’t mean it can’t be improved though, as I believe we should always strive towards excellence.

However, seriously consider what ‘safe’ means to you as an individual diver, what it means to diver training organisations and equipment manufacturers and whether you want to make that additional investment either in the effort, time or money to make your diving ‘safer’.

Safety is only one priority that must be balanced and it can never be the number one priority ALL the time for any organisation or individual. You can always thumb a dive before you get in the water, but it takes significant mental courage and self-awareness to do that.

If you liked this post, and think others would benefit from learning about the topic, feel free to post and share to your walls, groups and club sites. I am not precious about where my posts go...and if they end up in the bin, please tell me why so I can make the next one better.

If you'd like to learn more about this topic, come and see me at TekDiveUSA18 in Orlando 28-29 April on booth #109, or visit my new website here.


Gareth Lock is the owner of The Human Diver, a niche company focused on educating and developing divers, instructors and related teams to be high-performing. If you'd like to deepen your diving experience, consider taking the online introduction course which will change your attitude towards diving because safety is your perception, visit the website.