Q2. What are the contributions in this paper?
The paper presents a review of the main transport noise indicators, both the general acoustic ones and those used for specific transport modes. A critical analysis of the strengths and weaknesses of those indicators is provided, as well as a section discussing the framework in which they work, and suggestions for their best use, aimed at assisting decision-makers to ascertain their role in the evaluation process of the transport systems.
Q3. What are the effects of noise on human health?
Noise induces social and behavioural effects, notably annoyance and sleep disturbance; from a medical point of view, the effects of noise on human health are also well known: hearing impairment, speech intelligibility, physiological dis-functions, mental illness, performance reduction, cardiovascular diseases (WHO, 1999; WHO, 2011).
Q4. How much time is it necessary to carry out measurements?
carrying out measurements is a very expensive exercise and, to meet the Directive requirements properly, long time measurements are necessary.
Q5. What is the difficulty of achieving the targets?
The difficulty to attain those targets is that 80% of people live in the urban areas, where transport infrastructures represent the most important source of noise.
Q6. what is the use of factor analysis in the economic evaluation of noise effects?
While in Europe the use of Lden and Lnight indicators for the economic evaluation of noise effects is now common, this paper shows that decision-makers should jointly use noise and socio-economic variables to fully support their decisions.
Q7. What is the main reason why the general acoustic indicators are useful?
The general acoustic indicators are useful when it is just important to quantify the noise produced and, for this reason, both road and rail noise indicators stem from Leq, SEL and Lxx.