Perception, 2015, volume 44, pages 337 – 338
doi:10.1068/p4403rvw
Reviews
Human factors in lighting (3rd edition) by P R Boyce; CRC Press, Boca Raton, FL, 2014, 703 pages, $79.95 paper (£49.99) ISBN 9781439874882 Clocking in at just over seven hundred pages, the third edition of Peter Boyce’s Human Factors in Lighting is a formidable prospect to contemplate reading cover to cover, but used as a reference book it will form a useful part of any vision scientist’s library and/or an indispensable source of information to anyone who, like myself, works in the field of ergonomics (or, as it is sometimes called, ‘human factors’). Apart from the most cursory note of explanation that the subject matter of the book is the interaction between light and people, there is no discussion of what constitutes the field of ergonomics; nor is there any potted history of the discipline. Some may consider this a flaw in a book purporting to deal with ergonomic issues, but I found it refreshing to see an author get down to brass tacks immediately. The book opens with a discussion of the nature of visible light, its measurement, and how the lighting industry has attempted to standardise it. Despite the fact that it makes a lot of sense for a book dealing mainly with visual ergonomics to begin in this fashion, it makes for a tough first chapter. The discussion of CIE standards (never the most thrilling of topics), photometric units of measurement, and colour spaces is a fairly technical and mathematically dense way to open a book, and I fear it will bring all but the most committed reader down to earth with a jolt. There then follows a chapter on the general features of the visual system that, despite providing a useful review of the fundamentals of vision, can safely be skipped by readers with a background in the visual sciences. This chapter occasionally made me forget that I was reading a book about the ergonomics of lighting, since it reads very much like any other postgraduate-level vision science text book. An extended discussion of contrast sensitivity and spatiotemporal transfer functions is probably a tad too detailed for many ergonomists or architects, but should prove indispensable to anyone responsible for developing lighting systems. It is Boyce’s approach of pitching the text to the highest common denominator that ensures that the book is useful to as wide an audience as possible. The next chapter reviews the very recent anatomical and physiological discoveries regarding the nonimage-forming portion of the visual system, and this was a delight to read. It outlines the physiology of the intrinsically photosensitive retinal ganglion cells, their anatomical connections, theories and models currently being developed to describe the structure and function of this system, and how this system functions to regulate the circadian timing system. There is a review of several studies that show clearly how light can (and can’t) be used to shift the phase of the various hormonal components of the circadian clock. Most of the references in this chapter dated from the past few years, and it was hugely pleasing to see such recent research presented as a coherent narrative. The next portion of the book establishes some generalities about the effects of lighting on work and how this topic should, and should not, be studied in either the lab or the field. The section begins by presenting a conceptual model of the sort so beloved by ergonomists—in which most of the boxes unhelpfully have bidirectional effects on all the other boxes—but this is a rare break from Boyce’s modus operandi, which is simply to present the facts to the reader as they percolate out of the scientific literature. It is here, when Boyce begins discussing how lighting affects our ability to work, that the complexity of the task ahead becomes evident, since it can do so via a plethora of routes. The environmental lighting to which we are exposed can impair our ability to perform a task because it directly impairs our ability to see what we are doing; or because the level of lighting impacts upon our circadian timing system and reduces our general level of alertness; or because it causes us to become fatigued, which in turn impairs our general cognitive performance; or because it impacts upon our mood and motivation to perform said task, and so on. This section provides a salutary warning that the ergonomic literature should always be read with a sceptical eye to all these and other possible mechanisms of effect.
338
Reviews
The next couple of chapters discuss the more phenomenological aspects of lighting. The various sources of visual discomfort; glare, reflections, flicker, and nonuniformity of illumination; and their effects upon human behaviour are explained carefully and in detail and recommendations are made as to how these can be reduced or eliminated. Experiential qualities of lighting such as lightness and brightness, sparkle, and clarity are discussed; and the more subjective and higher level aesthetic perceptions such as formality, visual interest, harmony, and clutter are also addressed, although the author concludes that the sheer number of variables (both lighting-related and non-lighting-related) means that any attempt to predict these higher level perceptions is “doomed to fail” (page 222). Having discussed some generalities regarding the effects of lighting on our ability to work and our perceptions of our environment, Boyce then turns to the specifics of lighting in different settings; discussing in turn lighting for office environments, for industrial spaces, for the road, and for signage. Separate sections in the last half of the book deal with topics such as lighting and crime, light pollution, lighting issues for the elderly, and the effects of light on health generally. Of particular interest— in fact, one of the reasons that this third edition exists—are the sections dealing with the sweeping technological changes in lighting design brought about by the efforts in recent years to reduce electricity consumption, and the consequent impact of these changes on our visual environment. Of particular interest to me, dealing as I often do with emergency preparedness in marine and offshore installations, was the section on escape lighting. This chapter begins with a review of how different forms of emergency lighting, signage, and information presentation systems can improve people’s awareness of a developing hazard and speed up their decision to evacuate. Later sections of this chapter contain a great deal of quantitative data on movement speeds under different lighting conditions, visibility of way-finding elements in smoke-filled environments, and recognition of exit signage by individuals with colour vision abnormalities or low vision. These sorts of data will undoubtedly be of ongoing use to me and my many colleagues involved in the modelling of evacuation scenarios. It is the balance of hard facts, aesthetic considerations, and potentially life-saving practical applications that should make Human Factors in Lighting of interest to the many and varied readers of Perception. It is a fascinating and detailed reference work for researchers and practitioners working in ergonomics, architecture, lighting design, or basic vision science; but that is far from the limit of the book’s appeal. There is also something here for criminologists, economists, and engineers. The quality of our environmental lighting affects us all. Craig Aaen-Stockdale Principal Consultant, Human Factors and Ergonomics, Lloyd’s Register Consulting, Oslo, Norway; e‑mail:
[email protected] All books for review should be sent to the publishers marked for the attention of the reviews editor. Inclusion in the list of books received does not preclude a full review.
