3 How to go about assessing a risk

As stated earlier, the impact and probability must be considered in combination – not as discrete items – and the assessment must be made in line with any organisation guidance provided around expectations. In this section you will see how to assess a risk.

Firstly, consider the impact. Using the definition from Session 1, risk is defined as an uncertain event, but what most organisations are really interested in is risks that prevent them from achieving their objectives. The first step is therefore to understand the potential consequence(s) of interest to the organisation; this must be done bearing in mind that a risk can have more than one consequence. This may also mean in practice that some risks are discounted – those, for example, where the impact does not materially affect the company’s objectives.

Let us consider the risk inherent in driving a vehicle. While undesirable and something that should be avoided – both for the individual and for an organisation minor – ‘non injury’ accidents are of less concern than accidents that involve serious injury or fatalities. Therefore, if there are limited resources to manage the risk, as discussed in Session 5, the focus, individually and as an organisation, should be on reducing the risk associated with serious and fatal accidents. This approach, whereby a ‘single version of the truth’ is adopted, allows the organisation to fix the consequence(s) and focus on the root causes.

Activity 1 Road risks

Timing: Allow approximately 10 minutes

Now watch Video 2, which covers real-life examples of road risk, to explore how root causes will change our assessment.

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Transcript: Video 2 Road risk

NARRATOR

Road risk is a generic term applied to the risk in all activities associated to the road, but not limited to the road as a workplace.

As with previous examples, the term road risk is very broad, and may cover everything from road maintenance personnel, to cycle couriers, car drivers, and bus or lorry operators.

It is important, therefore, to focus the risk into what is of interest or importance when understanding the risk. And in this case, it is the risk of injury, and ultimately, loss of life that the majority of work and information rightly focuses on.

Let's look at some examples of how information or data might drive a risk assessment in regards to injury and loss of life on the road.

In this example, we will focus on the UK road network. Comparing the split between urban and rural roads of the same type, whilst all rural roads have a lower accident per billion miles than their urban equivalents, the percentage of the total made up by fatalities is around three times that of urban roads, suggesting that accidents on rural roads are more likely to lead to fatalities.

There may be many factors that influence a difference, but considerations may include road design, width, surface quality, lighting, traffic type, landscape, and even emergency response times.

20% of all injury related accidents occur in a speed limit of over 40 miles per hour. So 50, 60, or 70 mile per hour. Yet 52% of all fatalities occur in these speed limits. The corresponding swing is in under 40 mile per hour zones, which account for 80% of all injury-related accidents, but only 48% of all fatalities.

Approximately 25% of driving activity happens during the hours of darkness. All factors being equal, injury trends should be in line with this. But that is not the case.

Over 40% of fatalities, 31% of serious injuries, and 28% of slight injuries occur at night. This indicates that more accidents happen proportionally at night, and those accidents are more severe.

As with the road location, discussed earlier, there'll be many reasons behind this. Visibility, moving from lit to unlit roads, tiredness, and type of traffic will all play a part in this shift between night and day.

58% of injury accidents happen at junctions, where vehicles must cross paths to continue their journey. When looking just at junctions, it is evident that T junctions, staggered junctions, and crossroads play a significant part in all accidents, a trend which persists with serious and fatal accidents.

Roundabouts, on the other hand, show a declining trend in severity, from an injury accident through to fatality. This may not be solely down to road design. Other factors, for example, location or road speed, play a part. But road design may influence outcomes.

Some of the factors described above, combined with others not covered here, provide a driving environment across the UK that is varied, which creates different outcomes in terms of the number of accidents, their severity, and ultimately, the number of fatalities.

On the roads of Lincolnshire, fatalities occur far more frequently per million miles driven than in any other county in the UK. Similarly, serious injury in London is again far more frequent per million miles driven.

Understanding underlying factors- so in Lincolnshire, long, narrow roads with large, agricultural traffic; and in London, the number of pedestrians and cyclists mixed with HGVs and buses that may be driving these trends- is an essential step for anyone assessing roads risk in different locations, prior to considering what treatment to undertake.

End transcript: Video 2 Road risk

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Video 2 Road risk

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Once root causes have been understood the next step is to ask how likely the consequence is to occur. It is an important point to remember that the aim is to understand how likely is it that the risk will lead to the consequence defined previously, because as stated earlier the probability and impact are coupled.