MOVIMIENTO DE LA BANDA DESLIZANTE

This chapter describes the subjective safety effects of eight measures under the category of vehicle design and protective devices. The assessments are

summarised in table 5.4.

5.4.1 Reflective materials and protective clothing

Reflective materials and protective clothing consist of several measures. Among these it is only pedestrian reflectors and retro-reflective material on bicycles that are relevant in this project.

No studies have been found which directly evaluates the effects of these two measures on subjective safety, but some studies indirectly indicate that they may have a positive influence.

The conclusion of the qualitative considerations is also that reflective material on bicycles and pedestrians may have a small positive effect on subjective safety. The measures improve visibility of vulnerable road users which may lead to more thoughtfulness of car users and thereby much feeling of safety among vulnerable road users. In table 5.4, this is stated as improved sight, improved road light and improved thoughtfulness.

5.4.2 Cycle helmets

The effect of cycle helmets on subjective safety for cyclists has been evaluated directly or indirectly in several projects. Both the literature study and partly the theoretical, qualitative assessment show that cycle helmets increase the subjective safety for cyclists due to personally protection. Promoting use of use of cycle helmets is by law may however reduce cycling and led to traffic getting significantly closer when overtaking. In other words have a negative effect on subjective safety.

5.4.3 Regulating vehicle mass

The conclusion is that according to the literature study, regulating vehicle mass has a positive effect on subjective safety of vulnerable road users, but the qualitative considerations could not provide any clear conclusion in this respect. The measure probably gives less traffic by heavy vehicles. On the other hand the measure will also produce more traffic by light vehicles because one big heavy vehicle may be replaced by two or three small heavy vehicles. Also it is not unambiguous if speed will increase or decrease.

5.4.4 Regulating automobile engine capacity and top speed

No studies about the possible effects of these regulations on subjective safety have been found. However, the objective of the regulation is to reduce traffic speed. If successful, it will have a positive effect on subjective safety.

5.4.5 Under-run guardrails on trucks

Even though the measure addresses safety among vulnerable road users, no literature studying possible effects of the measure on subjective safety have been found. Additionally, it is assessed that side under-run guardrails has no effect on any of the factors influencing subjective safety of vulnerable road users.

5.4.6 Safety equipment in trucks

Safety equipment in heavy vehicles includes several types of equipment and regulations. Among these it is only total weight limit for heavy vehicles, length limit for heavy vehicles and extra mirrors and wide angle mirrors that are relevant in this project. It is concluded that these measures probably contribute to better subjective safety among vulnerable road users. However, no studies verify this assessment.

5.4.7 Bicycle safety equipment

Bicycle safety equipment includes measures as lamps, reflectors, brakes,

handlebars, wheels, gear, bells, distance marker, spoke protection, child seats and child bicycle wagons. Among this equipment, it is probably only the distance markers and bicycle lamps that directly affect the possible influencing factors on

subjective safety listed in this report. However, reflectors, bells, brakes, wheel, handlebars and child seats and wagons may also have some small effects.

Although the objective of this equipment is to improve conditions for cyclists, it is only lamps and indirectly distance marker that have been evaluated.

Based on very few evaluations and the qualitative considerations, the conclusion is that some of the bicycle safety equipment may have small positive effect on the feeling of safety among cyclists. But it does not affect pedestrians.

5.4.8 Safety standards for trailers and caravan

Safety standards for trailers and caravan include several measures. No studies that evaluate effects of these measures on subjective safety have been found.

It is assessed that the most relevant measures may have a small positive effect. A ban on driving with trailers and partly a total weight limit for trailers may reduce volume of the large heavy vehicles on the actual parts of a road network. This is typically in city centres with lots of vulnerable road users. The volume of small heavy vehicles may increase.

Speed limit may reduce the average speed.

Better stability and control of trailers may reduce unintended swings of the trailer, which improve the distance between the trailer and vulnerable road users.

5.4.9 Summary

Table 5.4 summarizes the most possible effects of the eight measures regarding vehicle design and protective devices on subjective safety.

Table 5.4. Summarise of the literature study and the qualitative assessment of the effect on subjective safety for eight vehicle design and protective devices. The rectangular bracket implies that the literature just indirectly indicated effect.

Traffic volume Heavy vehicle Vulnerable road users Speed Distance Crossing Distance Paths Separation/integration Intersections, design Crossings, number Road conditions Sight Road Light Thoughtfulness Skills Personally protection Qu

alitative assessmen t Literature Reflective materials - - - (↑) (↑) (↑) - - (↑) [↑] Cycle helmets - - (↓)? - (↓) - - - (↓)? - ↑ (↑) ↑ Vehicle mass (↓)? (↑)? - (↓)? - - - (↕)? [↑]

Engine and top speed - - - ↑ - - - ↑ -

Under-run guard rails - - - -

Truck safety equipment - (↑) - - - (↑) - - - - (↑) [↑] Cycle safety equipment - - - - ↑ - - - (↑) (↑) (↑) (↑) - (↑) ↑

Safety standards - (↑) - (↑) (↑) - - - (↑) -

Among the eight measures the effect on subjective safety has more or less been studied regarding five of them. No studies about regulating automobile engine capacity and top speed, under-run guard rails on trucks and safety standards for trailers and caravans have been found.

It is assessed that six of the measures most likely have a positive effect on subjective safety. Regulating vehicle mass can both have positive and negative effects, while under-run guard rails probably have no effect on subjective safety.