A Research Programme to Develop a Truck Driver Risk Assessment
Work-related crashes involving trucks represent a serious threat to both truck drivers and road users. Truck driving is among the occupations with the highest risk of fatalities and one study has reported that for each truck driver killed, an average of at least four other road users are also killed (Dionne et al, 1995). LGV drivers often drive for long hours on monotonous motorway journeys or drive large vans making ‘multi-drop’ deliveries often in urban areas under time pressure. Several studies have shown that it is these fatiguing and stressful components of work that contribute to increased risk of crash involvement for truck drivers. Therefore, to assess risk, a company must identify individual differences in response to driver stress and fatigue.
In 2004, Cranfield University embarked on a research programme to investigate the behavioural factors that can increase truck driver risk. Firstly, a review of the literature of the risk factors when driving large vehicles was undertaken; secondly a study of over 100 truck drivers from several major haulage companies across the UK completed the Driver Risk Index (DRI) to ascertain the relevance of the standard scales. Finally, a qualitative analysis of truck driver behaviour was conducted with participants from four logistics companies to explore the specific behavioural and situational risks when driving a truck.
The findings from the literature review revealed a range of risk factors that must be taken into account when assessing truck driver risk including age, experience, risk exposure, previous convictions, crash history, type of vehicle and load type, among several others. The second study concluded that the existing DRI scales to assess fleet driver behaviour were also relevant in describing truck driver behaviour. Similar driver risk factors between truck drivers and fleet drivers were found but not all items were retained and some scales were reversed so adaptations to the assessment were made. A third study involved a large sample of truck drivers from several logistics companies. This study uncovered specific behavioural risk factors including extrinsic sources of stress such as traffic environment and/or work demands and intrinsic sources relating to beliefs and attitudes to driving a truck for work.
Participants reported that the most significant source of stress were being held up in traffic jams, at road works or when loading/unloading leading to time pressure. Failure to meet the schedule means that a driver’s attention might be diverted away from driving safely or lead to increased risk taking as drivers try to make up time. Truck drivers also reported being annoyed when road users cut in front of them, take risks, or do not give their vehicle enough room to manoeuvre. Some truck drivers reported feeling frustrated and angry and taking risks as a result. Individual differences in coping with stress were also found with some truck drivers being able to reappraise the situation and take things in their stride. In contrast, less effective coping strategies involved a more confrontational approach and a tendency to ‘let of steam’ leading to increased speeds or driving too close to other vehicles.
Truck drivers also admit that fatigue is risk factor with prolonged driving resulting in symptoms of tiredness associated with slower reaction times and erratic driving performance. Fatigue-prone drivers reported greater levels of stress and increased vulnerability to distraction.
The results of this study led to the design of items included in the final assessment and then psychometric techniques were applied to the data drawn from over 300 truck drivers from many different types of companies across several geographic regions. Statistical procedures then enabled the research team to identify behavioural risk factors and ensure that the assessment accurately profiles the way truck drivers respond to the pressure of driving for work. The research programme culminated in the design and development of the Truck Driver Risk Index (TDRI) launched in January 2012.
The TDRI factors measure Driving Fatigue, Driving Excitement, Anxious Driving, Patient Driving and Work Related Risk assessing susceptibility to time pressure. Coping strategies include Driving Concerns (the tendency to become anxious and blame oneself for stressful situations) Confrontation (coping with stressful situations by being hostile to other road users) Driving Focus (increasing concentration on the driving task under stressful conditions) and Self-evaluation (stressful driving situations as an opportunity to learn and develop). The final section of the TDRI assesses the tendency to give favourable responses and identify those truck drivers that might hold an unrealistic view of their driving.
One of the major advantages of conducting a behavioural driver risk assessment is that it helps to identify high risk drivers that can then be targeted for more focused one-to-one driver training. This is especially useful for companies with large fleets and allows resources to be concentrated on the drivers that are more likely to be involved in a crash. Another important advantage is that the TDRI includes a management information system (MIS) which gathers all the data into an overall management reporting structure. The MIS enables the manager to easily monitor the entire driving risk management process, incorporating assessment, monitoring, review, compliance and audit trail, ensuring that the company has fulfilled its health and safety duty of care to its employees.