To explore the effects of lighting upon employees’ well-being in the workplace we must first define well-being. Well-being is a person’s perception of themselves as being comfortable, healthy or happy. When a person perceives one of these areas to be negatively affected, that well-being is reduced or ceases to be.
Taken for granted and overlooked, lighting is often a subject to budget cuts and value engineering. But it plays a crucial role in how people feel in a space. Most of the time, we notice lighting when a space is not lit well. But as the figures show, it pays to pay attention to the impact that lighting has on your workforce. According to the World Green Building Council’s research, exposure to natural light increases productivity by 18% and better lighting in general pushes up work rates by 23%. In contrast, a decrease in well-being will lead to an employee being less contented with their role at a company. This will often increase the likelihood of tardiness and non-attendance, as well as reducing productivity. A continued state of lacking well-being can also lead to a degeneration in an employee’s mental health and ultimately to depression.
During the nineties the impact of light on well-being began to be explained through circadian rhythms. These are the daily rhythms influenced by light and darkness that help our bodies to know when to wake up or when to sleep. A human’s circadian rhythm is a 24-hour cycle which alters with daylight, seasonal-light and climate. A change to these rhythms from a lack of natural light can cause people to have trouble sleeping and significant emotional and physical disruption. Our bodies react to darkness by creating the hormone known as melatonin which regulates sleep, so if there is not enough light feelings of lethargy will be caused by an excess of the hormone.
It was believed that by using lamps with different colour temperatures and dimming settings (set to a timer to replicate light throughout the day) that the circadian rhythm of a person would not be thrown off. However, as time progressed it has become the fashion to try and incorporate as much natural light alongside artificial light as possible.
Of course, well-being is not purely affected by lighting but research shows that it is one of the key factors in the workspace. Given this fact and that lighting is a relatively easily controllable factor, surely ensuring your company’s lighting is up to standard is a must...? Secondly, some of the other factors that influence well-being are affected by the lighting in the office-space. For example, social interaction is necessary to most workers’ feeling of contentment, if communal areas are poorly lit there is less likelihood that employees will spend time in them interacting with one another. 299 have been involved in several projects in which we have improved the communal areas through excellent lighting. Read more about our part in the developments at Colston Tower (where we utilised the Lopen Surface product for warm and well distributed lighting) and 78 Whitfield Street where Leck Suspended lighting was blended with natural daylight.
Workplace lighting and the need for it is very much affected by the seasons. During the winter months, many workers will arrive and leave work outside of daylight hours, meaning they will not see any natural light, except that which is let into the workplace. Therefore, it is essential that workplace environments make the most of this light or that the artificial light used in its place is not noticeably artificial. To achieve this the LEDs used will need to have controls capable of dimming and intensifying output. The products we use have 3 types of dimming settings; 1 to 10 (a manual analogue control for reducing output in 10% leaps), Phase (where the amount of time that full voltage is applied to the lamp is reduced to decrease the light emitted) or DALI (Digitally Addressable Lighting Interface), where a system assigns an individual address for each luminaire and they can all be controlled from a central computer. Finally, we are now looking into products with hybrid dimming, which can be dimmed with both Constant Current Reduction dimming (higher dimming range), and Pulse Width Modulation dimming (lower dimming range).
*If you’d like to know more about Hybrid dimming, please see the notes at the end of the page.
Without making use of dimming, employees are increasingly susceptible to the symptoms of SAD (Seasonal Affective Disorder) during the Winter months. At 78 Whitfield Street we blended natural light with artificial lighting, giving staff the illusion of natural light throughout day light hours.
78 Whitfield Street - Video
In instances where lighting is overly bright (both direct and reflected), glare can cause headaches, eyestrain, skin conditions and (in the most extreme circumstances) sight loss. This means that not only is it important to manage the output of LEDs into the task area but also how it is reflected from surfaces (i.e. floors, walls and ceilings). The direct output of light can be modified through use of diffusers. Diffusers soften the output of light to make it comfortable to the human eye. Modern diffusers used today have all but replaced parabolic louvers. Parabolic louvers (designed for fluorescents) were originally designed to prevent glare off computer screens with the specular aspect of the finish on the curved surfaces reflecting down at angles equal to or less than the shielding angle. In essence this simply meant that you would not be directly exposed to the source of light. Arguably, not the best-looking optics, we still see quality schemes value engineered and replaced by fittings using the parabolic louvers.
The market has changed in the last 10 years and at 299 Lighting, we now only use LED lighting (we have not used T5/fluorescent lamp product on our projects since 2015 and believe LEDs offer a far greater quality, flexibility and creativity of office lighting) which tend to have two varieties of diffusers. These are Opal diffusers; These have a single surface flashed with a milky white "opal" coating to diffuse light evenly. Opal Diffusing Glass or plastic can be used to achieve a near Lambertian distribution. The diffusion levels in opal glass/plastic causes a large amount of scattering light loss (an example of Opal diffusers can be found here). The second type of diffusers are Microprismatic; these cause softer luminance transitions between different surfaces and that is because the prisms of the micro-prismatic materials break light rays providing low glare light distribution from luminaires by eliminating light at high angles (an example of Microprismatic diffusers can be found here).
The impact of reflected light can be curtailed using light absorbing materials and paints. Ideal reflectance of surfaces are as follows; Ceiling cavity reflectance should be at 70-90%, wall reflectance should be between 50- 80% and floors should reflect approximately 20-40% of light (For more details refer to our ‘lighting regulations’ page).
Alternatively, faulty lighting (i.e. flicking intermediately or older style LEDS with varying colour outputs) can also effect the eyes, causing further headaches and is particularly hazardous for those suffering from light induced migraines or epileptic fits. There is currently a great deal of interest in the impact of LED flicker on mental health. CIBSE (The Chartered Institution of Building Services Engineers) & SLL (Society of Light and Lighting) are inviting organisations to pitch for a research project into human perception of flicker to ascertain if there are detrimental effects on performance.
Current research suggests that flicker causes irritation through the stroboscopic effect. This is a visual phenomenon caused by the misidentification that occurs when continuous motion is represented through a series of short light emittances. At low frequency bands the effects are more noticeable.
70Hz and below – Apparent to all
100 – 120Hz – Noticeable to a select few
120 – 160Hz – Almost undetectable
>160Hz – Not perceptible to the human eye
All products at 299 operate in excess of 120Hz and so should be imperceptible to all employees at a workplace.
Ideally, the lighting in a workplace will enable an employee to concentrate to the best of their ability for extended periods of time. Producing high quality work will give staff both a feeling of satisfaction and job security, boosting their overall well-being. Guidelines are in place (the following are taken from CIBSE’s website) that dictate the optimum Lux. For office spaces the task area should be between 300-500 Lux, in other working environments this can vary to as little as 100 Lux in Hotel Entrance Halls or as much as 700 Lux in showrooms.
The idea of having different Lux levels for differing workspaces is a recent one. Previously best practice was to ensure that all lighting was homogenous in its output proving a blanket 500 lux everywhere.
But lighting has evolved with the tenant in mind so that workspace lighting is first evaluated by what activities are being done in a space, therefore lighting varies across breakout spaces, meeting rooms, task areas. These areas require less intensive lighting, as a high level of concentration is not required and it gives employees’ eyes the chance to rest. The concept of variable lux levels through the space not only contributes to energy savings (don't forget the dimming and movement sensors could hugely contribute to more energy savings), but also gives the creative office fit out and architects an opportunity to express creative ideas and push the design of the office space further.
People should be in the centre of the design and the office space is not an exception.
To give an idea of how we utilise the office lighting and dimming settings, here are a few of our more popular products and their features;
The Oka can have DALI dimming, adjusting colour temperature from a warm 2700K to 5000K whenever the user requires and offers a direct-indirect distribution as well as a low, glare-free light for a healthy working environment.
The Faseny, with its expertly designed diffuser, it distributes omnidirectional light evenly making it a perfect choice for an LG7 designed work space. An early adopter to the latest LED technology of the tunable white, giving the user the freedom to select the colour temperatures between 2700K and 6500K.
The Lopen, energy efficient and with the ability to remove the diffuser. Available in 4 colours to suit the lighting of any workspace.
The Glyde, with its clear panel it supplies glare-free light for maximum visual comfort in any space. Lighting intensity can be dimmed via DALI and three colour temperatures are available to suit any application.
If you should have any questions relating to your lighting needs do please contact our team. We use our vast knowledge and experience as well as the latest Lighting design software, DIALux (for more information on how we utilise this programme click here) to ensure we get your lighting just right.
*Constant Current Reduction (CCR) dimming - for products dimmed only on higher range, e.g. 20% – 100%. On lower range, this feature can have a negative impact on the light quality (i.e. uneven light output and colour temperature variation).Pulse Width Modulation (PWM) dimming - for dimming range from 1% to 20%.