What is “personal office lighting” and why might we need it?
Historically, while a range of Certifications and Standards such as LEED or BREEAM have encouraged the development of efficient, low-carbon buildings it is only now that initiatives such as the IWBI’s WELL Standard have shifted the focus of building design firmly onto the wellbeing of the people occupying and using the spaces created.
Is office lighting healthy?
One of the elements that most powerfully and immediately affects both our emotions and our physiology is our lit environment. Homo Sapiens have been around on this earth for between 210,000 and 240,000 years now, and we have only had effective artificial lighting for around 150 years – our bodies simply haven’t evolved enough that being indoors under electric light is at all normal for us. This, together with the fact that most of us now spend around 90% of our time indoors and you can begin to see how unnatural our current lighting conditions are for us.
Way back in 1860 Florence Nightingale recognized how important natural daylight was to our general health and wellbeing when she wrote: “It is the unqualified result of all my experience with the sick that, second only to their need of fresh air, is their need of light; that, after a close room, what hurts them most is a dark room and that it is not only light but direct sunlight they want.”
–Florence Nightingale – Notes on Nursing: What it is and what it is not. 1860
So, you may see that there is a need for our lit environment to be more closely aligned with our individual requirements. Do current lighting design guidelines offer this? Sadly not.
To date, guidelines such as those published by CIBSE and the HSE concentrated on providing the minimum lighting that people need to do a certain type of work (e.g. in an office, a warehouse or factory, school). These guidelines offer advice on lighting levels loosely based around the type of task that they might be performing there. They also usually recommend a uniform lighting level across space which may very well suit some or even the majority of us but may well be completely unsuitable for a number of people depending on their sensitivities, conditions, age or the particular task that they may carry out.
Who is affected
We may be ‘night owls’ or ‘larks’ and there may be people that have Asperger’s, tendency towards migraine, low visual acuity, anxiety, SAD or depression all sharing a space and this is in addition to the very varied lighting requirements of people with different ages. For instance, a 55 or 60-year-old manager would need approximately three or four times as much light on a task area than, say, a 19-year-old intern to be able to complete the same task comfortably, speedily and accurately.
With this, many people feel uncomfortable or even become ill or sleep deprived if they are toiling under unsuitable lighting for many hours at a time. It is against this backdrop that the concept of “Personal Lighting” begins to make real sense. This means lighting that is right for you, whatever your age or sensitivities and given the task that you are trying to perform or even when you are relaxing.
The ‘right’ lighting should provide the correct light level (lux) for both ambient and task purposes
How do we achieve it?
Traditional workplace lighting designs typically have never-ending rows of light fittings installed in a suspended ceiling. These did an ok job of providing a uniform light across the horizontal surfaces such as desks etc but they offered very little in terms of meeting specific needs of many people. Creativity was restricted to ‘shall we install them at 1.8m x 2.4m spacing (500 lux) or 2.4m x 2.4m spacing (350lux)?’ This was a ‘catch-all’ solution that provided as many problems as solutions and it is little wonder that ‘sick building syndrome’ became such a big thing in the 1980s and continues in many instances today.
With the adoption of LED lighting suddenly energy efficiency became the holy grail with people chasing ever greater light outputs (lumens) for a given wattage input to reduce energy consumption and therefore electricity running costs. So far, so good. However, here we hit a paradox: How can we give varied lighting conditions suitable for a wide variety of psychological and physiological requirements while still using as little energy as possible?
Fortunately, technology and a bit of thought can provide us with some solutions
Variably lit offices
We can now provide a variable lit environment. The trend now is for a background ambient lighting level throughout a space to provide for Health & Safety requirements like stopping people bumping into the furniture etc with particular emphasis on lighting the vertical surfaces such as walls or office partitions and faces – people feel more comfortable and secure and they communicate with each other better when they can clearly see facial features. This background illumination can then be supplemented by localized lighting from either desk or floor mounted luminaires that provide targeted, controllable (both tunable white – cold/warm and dimmable) and efficient lighting when and where it is needed.
Remember that the most energy-efficient light is one that is switched off and the beauty of supplementary desk or floor standing luminaires is that they can be switched off when not required.
Freestanding desk lamps
The Waldmann range of freestanding and desk mounted luminaires are one of the most practical and affordable solutions that can provide the ‘right light, in the right place, for the right person at the right time’ and offer a range of light outputs. This sort of lighting requires little or no office reconfiguration which can be disruptive and expensive and can be switched on only when needed and moved to exactly where they will give the most benefit. In addition, this flexible solution gives users some control over their environment and, as we can all have ‘good days and bad days’ allows them to change the lighting to suit.
Change your floorplan
There are some other quite simple but cost-effective measures that can be taken to ensure the best visual landscape for occupiers of space. For instance, in an office, place desks near to windows so that people can get some contact with the outside world. If the windows look out onto trees etc then all the better but any view out is better than none. If those windows receive direct sunlight then provide some blinds that still allow daylight into the space but diffuse it so that the light is spread evenly and no one has to suffer a direct and uncomfortable shaft of bright sunlight for part of the day. Orientate desks so that people and screens are situated at 90degrees from the daylight. In that way, people looking up from their screens to rest their eyes for a few moments aren’t subjected to a harsh and uncomfortable contrast ratio caused by looking at bright sunlight.
Think about your surfaces & materials
Make sure that reflective surfaces such as walls, ceilings, desktops and even flooring are kept quite light to make the spaces seem bigger and to maximize the effect of the lighting. Contrary to popular belief, matt surfaces are better than shiny for providing a good, even reflective value.
Where breakout areas are provided, ensure that there is some variety in the lighting levels so that some spaces become cosier and conducive to relaxation so people can recharge their batteries!
Terry John is our independent lighting consultant who can offer independent and detailed lighting surveys of existing installations and provide guidance and advice for the correct lighting in a wide variety of workplaces from offices to factories, from hospitals to universities. Having worked for some of the major UK and European lighting companies for more than 30 years, Terry can bring the experience gained over a wide range of projects to help you with yours. Please get in touch if you’d like to find out more about lighting surveys for your workplace