Good lighting consists of a number of factors, such as light quality, brightness and correct positioning, as well as colour rendering. This short guide also discusses the importance of lighting design, the importance of energy efficiency and how dimming can save energy while creating an ambience.
Good lighting consists of several factors
- Light intensity is crucial to the functionality and atmosphere of a space.
- Colour temperature affects mood and personal alertness
- The colour rendering index (CRI) determines how accurately light reproduces colours.
- Ergonomic lighting design ensures comfort and efficiency when using the space.
The importance of light intensity
Light intensity, or ‘light intensity’, is crucial to both the functionality and the ambience of a space. The importance of light intensity cannot be overstated. Not surprisingly, more light is often needed in precision workplaces.
This is not just for comfort – good lighting ensures that tasks are carried out accurately and without strain. For example the requirement for 500 lux lighting in retail areas brings out the colours and details of products, which is important for sales.
On the other hand, a modest 100 lux lighting is sufficient to guide you safely along the corridor. LED lamps, with their long life and low energy consumption, show that where light is needed most, it can still be efficient and cost-effective.
Effects of colour temperature
The colour temperature of the lighting has a significant impact on how you experience the atmosphere of a room and your own state of alertness. Choosing the right shade can be a challenge, but once you understand the effects of colour temperature, you can choose the right light for every situation.
- Bright daylight (5000K+): increases alertness and supports concentration – ideal for workspaces.
- Neutral white (4000K): balances energy and relaxation, suitable for a wide range of environments.
- Warm white (<3000K): creates a calming and inviting atmosphere – perfect for living areas.
By choosing the right colour temperature, you can maximise the comfort of your space and optimise lighting efficiency. Remember that the quality of light can be as important as the lighting itself.
The importance of colour reproduction
When choosing lighting, it is important to consider the Colour Rendering Index (CRI), which determines how well light reproduces colours accurately. A high CRI value indicates that the light presents colours in a natural and vivid way, which is an essential part of good lighting, and that the eyes work better. The importance of colour reproduction is particularly highlighted in spaces where accurate colour reproduction is crucial, such as art galleries and shops. Nowadays, people are demanding a sense of colour in their homes too.
LED strip is a popular lighting solution because it offers not only energy efficiency but also excellent colour rendering. By choosing LED strips that offer a high CRI, you ensure that the lighting supports the aesthetics and functionality of the space. Therefore, accurate colour reproduction is as important as the amount and quality of light.
Ergonomic lighting design
In order to ensure the comfort and efficiency of the space, ergonomic lighting standards must be taken into account at the design stage. The ergonomic design of lighting affects quality and comfort in many ways and is crucial, especially in workplaces.
- Lux levels: the SFS-EN 12464-1 standard defines how much light is needed in different spaces.
- Colour temperature: good lighting takes into account the natural colour temperature, supporting the human circadian rhythm.
- CRI: High colour rendering index is essential in environments where precision work is required.
Taking these factors into account will help create a space that not only looks good but also promotes health and productivity.
SFS-EN 12464-1 standard
SFS-EN 12464-1 is a European standard focusing on indoor lighting in workplaces. The purpose of this standard is to ensure that lighting in the work environment is suitable and safe for the different tasks. It includes recommendations on lighting intensity, light quality, light distribution and glare control, among other things.
The standard takes into account people’s visual needs and well-being in the work environment. It sets requirements for the lighting of different work tasks, such as office work, industrial work and special tasks. SFS-EN 12464-1 also addresses the design and implementation of lighting in a way that promotes energy efficiency and environmental sustainability.
The standard is part of the wider SFS-EN 12464 series of standards covering lighting in different environments, including outdoor lighting (Part 2). Compliance with the standard will help ensure that lighting supports the health and productivity of workers, while reducing energy and maintenance costs.
UGR
UGR, or Unified Glare Rating, is a metric used to assess glare in lighting design. It is part of international lighting standards, such as the CIE (International Commission on Illumination) guidelines, and has also been incorporated into many national standards such as SFS-EN 12464-1.
The UGR value helps determine how likely lighting is to cause disturbing glare for people in a given space. Glare can be caused by direct or indirect light and can affect people’s comfort and ability to perform visual tasks.
UGR values are usually classified as follows:
- UGR < 10: No detectable glare.
- UGR 10 – 13: Very low risk of glare.
- UGR 13 – 16: Low risk of glare.
- UGR 16 – 19: Moderate risk of glare.
- UGR 19 – 22: High risk of glare.
- UGR > 22: Very high risk of glare.
UGR is calculated using a very complex formula that takes into account a number of factors, such as the brightness of the light sources, the position relative to the viewer, the viewer’s viewing direction and the reflectance of the environment. The purpose of this calculation is to estimate how disturbing lighting is for the average user in a given space.
Good UGR is particularly important in working environments such as offices, schools and industrial premises where poor lighting and glare can reduce visual comfort and work efficiency.
UGR formula
UGR = 8 * log(0.25 / L_b * sum(L^2 * omega / (p^2 * (1 – cos(theta))^2)))
Where:
- L is the luminance of the light source (cd/m²).
- omega is the visible surface area (in steradians) of a light source.
- p is a distance parameter related to the position of the light source (relative position of the light source with respect to the observer).
- theta is the angle of the light source with respect to the line of sight of the observer.
- L_b is the background luminance (cd/m²).
Example:
Suppose we have an office space with multiple light sources and we need to calculate the UGR. We select one light source and set the necessary values:
- Assume L = 3000 cd/m² (luminance of the light source).
- omega = 0.005 sr (visible area of the light source).
- p = 0.7 (distance parameter, depending on the position of the light source).
- theta = 60 degrees (angle to the viewer’s line of sight).
- L_b = 200 cd/m² (background luminance).
We use these values in the formula to calculate the UGR.
UGR Calculator
LUX
“Lux” (symbol: lx) is a unit of measurement used in lighting technology to express luminous intensity, i.e. how much light falls on a given surface. It is an SI (International System of Units) unit based on lumens per square metre (lm/m²).
Here’s a simplified explanation:
- Lumen (lm): lumen is a unit that measures the total luminous flux of a light source, i.e. how much visible light it produces.
- Lux (lx): when this luminous flux is distributed over a given area, the luminous intensity in lux is obtained. One lux means one lumen per square metre.
For example, if a 1000 lumen light source illuminates an area of 10 square metres evenly, the illuminance in that area is 100 lux.
Optimising energy efficiency
You’ll see a clear reduction in your energy bill when you optimise your lighting system to be energy efficient. By choosing LED lamps and luminaires instead of traditional halogen or incandescent bulbs, you are choosing a path to significant energy savings. Optimising energy efficiency is the key to both managing the initial investment and achieving long-term benefits. With professional lighting design, you ensure that every aspect, from installation to operation, works to achieve lower lifecycle costs.
Efficient lighting control systems, from smart to smart options, increase comfort while saving energy. Switching on and off is effortless, and you can adjust the settings to suit your daily routine. However, care during installation is important to ensure that you get the full benefits of an energy-efficient lighting system.
Frequently asked questions
How can intelligent lighting systems adapt to different times of day or user preferences?
You can tailor intelligent lighting systems to suit your daily routine and tastes. They use intelligent dimming to adjust brightness gradually, mimicking natural light variations. The colour temperature changes to match the time of day, providing a warm glow or a fresh brightness. Presence sensors detect your presence and optimise lighting use to save energy. These features work seamlessly together, ensuring comfort and efficiency in your home or workspace, tailored to your individual needs.
Do individuals with photosensitivity or visual impairment have specific lighting recommendations?
Recommendations often include adjustable lighting systems that offer personal control over intensity and colour temperature, ensuring you can create an environment that meets your unique needs.
