Strategic environmental noise mapping: Methodological issues concerning the implementation of the EU Environmental Noise Directive and their policy implications

Abstract

This paper explores methodological issues and policy implications concerning the implementation of the EU Environmental Noise Directive (END) across Member States. Methodologically, the paper focuses on two key thematic issues relevant to the Directive: (1) calculation methods and (2) mapping methods. For (1), the paper focuses, in particular, on how differing calculation methods influence noise prediction results as well as the value of the EU noise indicator L_den and its associated implications for comparability of noise data across EU states. With regard to (2), emphasis is placed on identifying the issues affecting strategic noise mapping, estimating population exposure, noise action planning and dissemination of noise mapping results to the general public. The implication of these issues for future environmental noise policy is also examined.

Introduction

In 1994 it was estimated that during day-time, approximately 22% of the total population of the EU were exposed to noise levels from road traffic exceeding a daily equivalent sound pressure level of 55 decibels (dB(A)) (Lambert and Vallet, 1994). Moreover, 49% of the population (77 million) were considered to live in ‘grey areas’ of acoustical discomfort to residents. During night-time, more than 30% were considered to be exposed to equivalent sound pressure levels exceeding 55 dB(A) which is considered to be disturbing to sleep (Berglund et al, 1999). Clearly then, the scale of environmental noise exposure is large. Given the recent enlargement of the European Union (EU) to take in Member States in Eastern Europe, it is reasonable to expect that the foregoing figures considerably underestimate the extent of the problem within the existing Union.

The relationship between environmental noise and public health is perhaps the most significant reason why environmental noise has emerged as a major issue in environmental legislation and policy in recent years (European Commission, 1996, Berglund et al., 1999, World Health Organisation (WHO) and European Centre for Environment and Health, 2003). Moreover, much research has emerged over the last two decades linking environmental noise with detrimental health impacts. Most important of these are annoyance (Michaud et al, 2005) and sleep disturbance (Carter, 1996, Ohrstrom & Skanberg, 2004). However, other dose–effect relationships include negative emotions such anger, disappointment, unhappiness, anxiety and even depression as well as mental health impacts (Fidell et al., 1991, Fields, 1998, Miedema, 2003, Michaud et al., 2005, La Torre et al., 2007). A further area of concern is the link between noise exposure and cardio-vascular disease (Babisch et al., 2003, Babisch et al., 2005 while noise has a particularly negative impact on children's health (Evans & Lepore, 1993, Evans et al., 2001, Evans & Maxwell, 1997). Indeed, it is within this context that the EU Environmental Noise Directive emerged. Moreover, a more recent WHO report has pointed out that ‘for the primary prevention of subclinical adverse health effects related to night noise in the population, it is recommended that the population should not be exposed to night noise levels greater than 40 dB[A] of L_{night,outside} during the part of the night when most people are in bed’ (WHO, 2009, 109).¹ They also recommend that 55 dB(A) be used as an interim guideline value for countries who cannot meet the value of 40 dB(A) in the short term.

Bearing this in mind, this paper explores methodological issues and associated policy implications concerning the implementation of the EU Environmental Noise Directive (END) across Member States. Methodologically, the paper focuses on two key thematic issues relevant to the Directive: (1) calculation methods and (2) mapping methods. For (1), the paper focuses, in particular, on how differing calculation methods influence noise prediction results as well as the value of the EU noise indicator L_den and its associated implications for comparability of noise data across EU states. With regard to (2), emphasis is placed on identifying the issues affecting strategic noise mapping, estimating population exposure, noise action planning and dissemination of noise mapping results to the general public. The implications of these issues for future environmental noise policy is also examined.