A method to include in lca road traffic noise and its health effects

Background, Aims and ScopeTransport noise represents an environmental problem that is perceived by humans more directly than the usual chemical emissions or resource uses. In spite of this, traditional LCA applications still exclude noise — probably due to the unavailability of an appropriate assessment method. In order to fill the gap, this article presents a study proposing a new computational procedure for the determination of health impairment resulting from noise emissions of road vehicles.Main FeaturesThe magnitude of health impairment due to noise is determined separately for each vehicle class (cars, trucks,..) and is calculated per vehicle-kilometre driven during the day or at nighttime on the Swiss road network. This health impairment is expressed in cases of sleep disturbance or communication disturbance, and furthermore aggregated in DALY (Disability Adjusted Life Years) units representing the number, duration and severity of the health cases. The method is modelling the full cause-effect chain from the noise emissions of a single vehicle up to the health damage. As in some other modern concepts of environmental damage assessment, the analysis is subdivided into the four modules of fate analysis, exposure analysis, effect analysis and damage analysis. The fate analysis yielding the noise level increment due to an additional road transport over a given distance is conducted for transports with known or with unknown routing, the latter case being more important in LCA practice. The current number of persons subject to specific background levels of noise is determined on the basis of the road traffic noise model, LUK, developed by the Swiss canton of Zurich. The number of additional cases of health impairment due to incremental noise is calculated with data out of the Swiss Noise Study 90. An assessment of the severity of sleep disturbance and communication disturbance, in comparison to other types of health impairment, was performed by a panel consisting of physicians experienced in the field of severity weighting of disabilities.Results and DiscussionThe quantities of health cases and of DALY units are given per 1′000 truck or car kilometres on Swiss roads, and the range of the confidence interval is estimated. A plausibility check is made by a quantitative comparison of the results with health damage due to traffic accidents in Switzerland, and with health damage due to traffic noise in the Netherlands.Conclusions and OudookThe method is ready for use in LCA practice. However, the temporary solution for transports outside of Switzerland should be replaced by feeding country specific data into the fate and exposure model. Further, a comparable assessment for rail transport would facilitate decisions on road or rail transport. A decisive element of transport noise assessment is the availability of robust links between noise level and medical conditions. Whilst the number of the corresponding studies is sufficiendy large, a design for better pooling of study results is desirable.