Unlike the home, the office and workplace need special lights, which should guarantee not only energy efficiency and durability, but also quality standards suitable for not straining the eyes in the event of work from a video terminal or on technological equipment. Office lighting, in this sense, requires specific attention, aimed at making the most of productivity by creating a welcoming environment both in summer, when natural light abounds, and especially in winter and in those places where the contribution of light is minimal. All this, if possible, in compliance with the guidelines established among others in the precious Manual available for download the video workstations.
It being understood that each project should be analyzed and evaluated critically, there are essential points that are independent of the type of office you wish to illuminate. We at led screen supplier want to share with you the salient aspects of office lighting, or the rules that you need to know and apply for a truly efficient and comfortable office at any time of day and in any season of the year. Here are the 5 points to keep in mind.
Everything starts from here. The light sources in an environment can be of two types: natural or artificial, in both cases from direct or indirect light sources. Direct light sources provide more intense lighting, useful on the work area, but they risk leaving other areas not directly lit in the shade, accentuating the contrasts. On the other hand, indirect light sources, which use for example the reflection of light from the ceiling for diffusion throughout the room, limit the differences in brightness but introduce a more homogeneous light in which often the shadows and contrasts are attenuated.
In a work environment, mixed direct-indirect lighting is preferable, such as to avoid excessive contrast between the areas that receive direct light and the other areas of the environment, leaving good lighting in the work area, or through sources of direct light with diffusers and screens. Light sources or their reflections must not fall within the visual field of the operator at the video terminal: by using direct but partially shielded lights, in which the angle of emission of direct light is restricted, the possibility that the light source or its reflection is limited you are in the operators’ field of vision.
2) THE RIGHT BALANCE BETWEEN NATURAL AND ARTIFICIAL LIGHT
According to what was written in the previous point, it is fundamental to balance natural light and artificial light. Where possible, it is recommended to give priority to natural light: it goes without saying that there will be situations where there is insufficient natural light, even only in some moments of the day. It depends on the place, on the presence or not of large windows and on the exposure. Skillfully combining lights, intensity of sources and distribution is the best way to maintain health and protect the environment.
3) UGR CONTROL OVER THE DESKS
In all offices and workplaces where computers are present and where employees spend most of their working day in front of their PC, it is very important to study UGR, which stands for Unified Glare Rating. It is an internationally recognized and shared value, which identifies the glare conditions within an environment. Without going into too much detail, it is enough to remember that glare is one of the greatest dangers for the sight when working on the video terminal.
The cause is to be found in the high risk of visual fatigue related to the eye effort in counterbalancing the amount of light (in small what happens as when you look at the headlights of a car for a long time). For this it is necessary to position the lights preferably on the sides and not in front of or behind the screen: the work station must be adjusted so that both the light source and its possible reflection do not enter the field of vision. An advice? Light sources with a very narrow light emission angle limit the formation of reflections.
4) QUANTITY AND TONALITY OF THE LIGHTING
The lighting of a workplace depends on several parameters. In addition to those already listed so far, it is a priority to establish the amount of light that reaches the work area : an amount (defined as illuminance) that is measured in lux (expressed in lumens / m2, or as luminous flux emitted by a source that hits a surface of one square meter). The lux must be proportionate to the type of activity that is carried out in the office or workplace. The light reflected by an illuminated object is instead luminance and is measured in cnd / m2: this value indicates the luminous flux emitted or reflected by a surface in relation to the size of that surface, and in a specific direction (in this case towards the ‘observer).
Two differently lit surfaces have a “luminance ratio” between them (L2 object / L1 background) which indicates this difference in relation to the glare effects (for example a very bright object on a dark background, or a shadow object on a very bright background). Luminance also allows you to calculate the “contrast factor”, i.e. the ratio of the difference in luminance of an object and its background and the luminance of the background itself (L2-L1) / L1. The result allows to evaluate the degree of visibility of an object. Conditions in which the luminance contrasts are too high lead to visual fatigue due to the continuous need to adapt the eye by moving the gaze from one point to another.
According to the legislation, and also based on the INAIL’s advice given in the guide we mentioned in the introduction, for an ideal work environment in which general activities are carried out with a medium level of attention – such as office environments and workstations at the video terminal – the area lighting must be higher than 500 lux . For more complex activities that require greater precision (design, graphics, drawing) the lighting intensity must be higher, between 750 and 1000 lux. It should also be remembered that natural light, corresponding to approximately 4,000 K, is suitable for work environments and offices where a good concentration is required.
5) EFFICIENCY AND ENERGY SAVINGS
The last point we want to focus on is energy efficiency. We live in an era of opportunity, where the most modern technologies allow us to cut consumption and reduce bills. An era in which recent regulations have banned old incandescent lamps, precisely to favor the transaction towards a more sober and less dependent on fossil fuels society. Lamps that use LED are by far the best in terms of energy savings: they last longer, require no maintenance and consume less than half. Given the costs that an office has to bear, switching to LED is undoubtedly the most forward-looking choice!