Edited by Navaz Davoudian. Routledge, 2019, ISBN: 9781859468210

Marilyne Andersen (Ecole Polytechnique Fédérale de Lausanne - EFPL) reviews this book which offers insight into the different factors that shape successful night-lighting in urban environments, including: the role of light in public spaces; occupant acceptance; and luminence distribution.

This book offers a multifaceted perspective on the importance and challenges of lighting cities for people. Through a rigorous combination of theory and practice-based approaches, it provides the reader with well-articulated principles, experiment-based learnings and both lucidly and comprehensively evaluated examples that lie behind a successfully night-lit urban environment.  

Without suggesting a paradigm shift in approaching urban lighting, the book brings a new understanding about the multi-dimensional nature of urban lighting by taking an encompassing perspective, notably by addressing the psychological, behavioral and social influence that urban lighting has for the people that experience it.

The key question that the book tries to address pertains to the transition from research to design and practice. The approach adopted starts by setting principles and stating the problem, and moves forward by diving into the specifics of representative case studies. Its novelty thus relies on investigating the numerous factors that play a role in a successful night-lighting design and go well beyond lighting technology questions, without ever overwhelming the reader with the underlying complexity of their interactions. Instead, it offers a range of pragmatic means to establish priorities in this process.  

The Introduction section, written by the editor, offers a broad and insightful dive into the topic of the book, namely urban lighting design. By addressing questions of the meaning and pertinence of evidence-based design in this context, and connecting it to more fundamental issues of knowledge, of science and of practice, it is very efficient in engaging a wide audience of readers -researchers, practitioners, planners and policy makers - into the topic by connecting the many dimensions of urban lighting to one another, from social and behavioral considerations to efficacy and policy-oriented ones, while offering specific and tangible information about them, rather than generalities.

The content presented in the subsequent chapters, especially in Parts I and II, is able to maintain a comparable level of pertinence. Taking different perspectives, these chapters offer various entry points to the inherent multi-disciplinarity embedded in urban lighting design as it requires expertise from different fields like environmental psychology, social science, urban planning, landscape and architectural design and of course photometry and lighting technology. Tackling questions as broad as the meaning and relevance of the social dimension, which encompasses questions of generational specificities but also of community-level versus individual expectations for instance, and as practical and useful as methodological principles behind collaborating across the fields mentioned above, the book is a journey into the importance, relevance and challenges of making cities lit for their users, particularly at night. It thus speaks as much to designers and planners as it does to economists or researchers, as long as they share an interest in understanding more about what lies behind decisions made for urban lighting - or what should. Such chapters tend to be quite broad in scope while others can be extremely focused and include quite technical, research-based parts - like chapter 3 and 4 on bringing in the urban lighting needs of the elderly. In these chapters, the specific needs of elderly people are presented and discussed at various levels, such as how the ageing of the eye or the adaptation of behavior and fears when we get older does and should influence how we design urban lighting at night. It also warns us about the danger of simplistic solutions that would not account for these changes and offers clear recommendations towards more adapted lighting principles.   

The different topics are introduced elegantly and raise the reader's interest early on, while the statements made are backed up by either research, experience or existing literature in a convincing way. Thanks to this approach, the book can be read by the general public interested in the subject or curious to better understand why certain urban environments are lit in certain ways, as much as to policy makers, who may want to come up with a well-informed strategy for future urban developments.  The principles and lessons learnt are amply and nicely supported by concrete examples of lighting design projects not only to which they apply, but also in which their limitations and challenges can be revealed. Some of these projects, like the Whitecross Estate or the Narrow Way in chapter 1, have a dedicated focus on the acceptability of projects by their intended occupants, with very interesting lessons learned regarding the difference in perception between designers and users. The Granary Square project, on the other hand, is used in chapter 2 to discuss the need to establish a robust collaborative framework within the highly diverse project team. This project is referred to again in chapter 6, but from a very different perspective and scale, namely luminance distribution in one's field of view. As further discussed also in chapter 5, the reader gets to appreciate the role of light in shaping public spaces and to better understand our response to it, by diving into quite specific concepts such as the visual saliency resulting from a given lighting scenario and its role in addressing wayfinding issues. As these examples are quite diverse, they cover a relevant range of contexts and of challenges typically faced in lighting urban environments.

What is particularly notable in the Part I and II chapters is how carefully the authors sought to keep an objective standpoint, with ample documentation based on research or on experience gained from professional practice: the latter - whether research or practice-based - oftentimes included their own work but was expressed in a neutral way, without ever highlighting their own accomplishments over the message to be remembered overall. This aspect distinguishes these two parts from Part III which is dedicated to the presentation of a selection of projects from the Arup Lighting group in chapter 7, used as successful lighting design examples to help further illustrate what was learned in Parts I & II. In this last chapter, a rich diversity of lighting design projects is offered, together with their evaluation in hindsight. The authors propose different points of view for their case study analyses, so as to exemplify the different concepts that can lie behind a given lighting design (e.g. connection versus discovery), to illustrate the influence of context or discuss the confrontation between experience and compliance taken too literally, as well as the range of opportunities offered by emerging technology.

The last section of each of the chapters, entitled 'Key learning points', represents another remarkable component of this book, that very effectively makes the information presented accessible. It does this by providing a clear and useful synthesis of the most memorable lessons to learn which, rather than becoming high level summaries, instead lists some carefully selected, insightful and specific messages that pertain to the chapter they close. This makes it easy for both experts and non-experts to know which take-home messages to focus on depending on what drove their interest in the topic in the first place, which further helps in reaching out to the book's audience.

As becomes evident when reading this book, urban lighting is not a static or resolved issue, nor can it be addressed from a technical standpoint only. It requires to bring together a range of competences and experiences, and to closely connect research and evidence-based knowledge with practice and design at various scales - from the individual to the collective, and from a single product to a whole neighborhood.