- “monitoring casualty trends and evaluating policies which have been introduced to improve
safety, in order to provide a sound basis for developing new policies
- comparing the levels of risk of different types of travel ( for example by transport environment or
transport mode)
- setting priorities, that is identifying those transport situations with high levels of risk in order to
formulate policies and concentrate resources to reduce risk levels, especially for high severity
crashes (ETSC,1999).”
The safety policy for each mode of transport should be similar: research,
develop and apply cost-effective countermeasures that have the potential to
reduce crash risk and/or severity.
A basic assumption is that it is desirable to strive for equal risk to various
categories of road users, including the vulnerable road user, in order to
achieve equal risk on various categories of roads. Unequal risks on different
categories of roads and for different categories of road users do, however,
exist and it is almost impossible to envisage that such risks can be made
equal at reasonable economic costs. Similarly, equal risks in various parts
of the country, municipalities, regions, and provinces are almost certainly
unachievable at reasonable economic costs. Even the calculation of such
risks is almost impossible because of the lack of reliable and detailed
exposure data on the provincial and municipal levels.
If good data is not available, one resorts to the usual levels of aggregationnational,
provincial or municipal- per inhabitant, per kilometre of road, etc.
At the regional and municipal levels there is also the problem of interpretation.
Some authorities have high levels of risk but have done a lot of
work on road safety, others have done little. What is the correct measure of
risk? At a high level of safety, the additional effort required to achieve more
safety is much greater (more costly) than at lower levels of safety, and so
positive results are more difficult to achieve. A further complication arises
from the fact that equal levels of risk are unrealistic if conditions are not
equal. Large municipalities generally also have higher population densities
and have more congestion than smaller towns. As a result they will experience
lower numbers of fatalities and seriously injured victims per capita.
Similarly, provinces or regions that are highly urbanised will have higher
population densities and experience lower levels of fatalities and serious
injuries. This issue will be discussed in further detail in Section 4.6 which
considers the cost-benefit considerations of safety measures and in section
6.1 which discusses accident rates and traffic flows.