How to light your office when teleworking

Lighting in the workplace is one of those ergonomic factors that guarantee good performance and comfort for the worker and ensure all the Occupational Risk Prevention guidelines are being followed. And this applies to lighting at the office and when teleworking from home.

Perhaps due to the speed with which the first wave of the coronavirus hit, many teleworkers have become accustomed to 'garage' offices. Any old chair, working from the sofa, resting the computer on any flat surface that can be found in the house, and little else. Many people don't even think the lighting in their office is important when they are teleworking. But, it is.

Why is workplace lighting so important?

Workers usually spend about eight hours a day in front of the computer, either at the office or in the study they have set up at home. Sometimes even longer, even if this is not recommended. These activities occupy at least a third of the day, and exposure to poor lighting (due to lack or excess of light) can lead to significant damage to our system.

One of the most well-known factors in workplace lighting is its adaptation to the circadian rhythm. The daily biological rhythm. When a person wakes up, they expect to see a certain level of luminosity, which the brain interprets as the rising of the Sun, releasing the hormone cortisol and activating the body. When this does not happen, levels of the hormone melatonin increase.

Today it is known that, due to the disruption of this circadian rhythm, night shift workers experience increased blood pressure, a higher chance of suffering cardiovascular disease and metabolic abnormalities (including type 2 diabetes) and it even suppresses the immune system, promoting the appearance of diseases such as bowel or breast cancer.

A good part of all these conditions appear when there is inadequate lighting at the right time, always bearing in mind that humans are a type of diurnal mammal that expects to see certain light levels as the day progresses, and that sleeps at night. This should be taken into account, as far as possible, when lighting the workplace.

This is an ideally lit telework station

When choosing workplace lighting, it is important to understand some of the basic characteristics of lighting systems. The guide ''Lighting in the Workplace'(2015), from the then Ministry of Employment and Social Security, advises paying special attention to the following elements:

1. Colour temperature between 3300 K and 5300 K. Colour temperature, also called apparent colour, describes the relative colour of the light source. All bulbs include their colour or range of colours on the box when you buy them.
2. Colour rendering or colour rendering index (Ra or CRI) the closer to 100 the better. This indicates the ability of the light source to represent colours accurately. Class 1A (CRI ≥ 90) can be found on the bulb boxes.
3. Lighting level or illuminance (not to be confused with luminous flux, luminous intensity or luminance) close to 300 lux or 500 lux, depending on the work being performed, the minimum being 100. Generally, a specific device is required to measure lux. It must be set up by the company.

A very common mistake is to place the computer against the light, as seen in the image, or against sunlight. This often causes noticeable eye discomfort and dizziness by forcing the worker to squint to adjust to the excess light, and at the same time forcing them to increase the screen brightness in order to see anything. The best set up? Work at about 90º from the source of natural light.

Also, if you are remotely working in front of a computer, the optimum colour temperature is close to 5300 K in the morning and 3300 K at dusk, with a colour rendering of class 1A and an illuminance of 500 lux. It is very important to be able to change the brightness of the device's screen.

To relieve eye fatigue (asthenopia) derived from looking at a closely positioned screen, it is advisable to look into the distance from time to time. For example, through a window next to the desk, taking advantage of interruptions such as calls to fix the eyes on objects as far away as possible. And, at the same time, reduce the lumens on the screen to adapt them to the ambient light.

This is what the law says about lighting the office when teleworking

The minimum lighting standard at a work station or teleworking desk is set by Royal Decree 486/1997. According to this document, the minimum lighting conditions are:

• Whenever possible, workplaces must have natural lighting, supplemented with artificial light when insufficient.
• Preference for general or diffuse lighting, complemented by focused light when necessary.
• The minimum lighting levels are:

• La distribución de los niveles de iluminación será lo más uniforme posible.
• Se evitarán deslumbramientos.

Why should we insist on natural lighting in the workplace?

Human beings have evolved being exposed to sunlight at very precise wavelengths and energy levels that are modulated by the atmosphere. In the morning, the sunlight is more bluish and it is thanks to this that the hormone cortisol is released that wakes us up. In the afternoon, the light is orange and the hormone melatonin is released. It helps you rest and get a good night's sleep.

We have already seen some of the consequences for the body of disrupting this balance. From disorders caused by stress to diseases with serious consequences. It is therefore a priority, as far as is possible, to adapt lighting in the teleworking station to the sunlight in the real world. According to the official document 'Lighting in the Workplace', natural lighting:

• Produces less eye fatigue.
• Allows colours to be appreciated as they are.
• Is the most economical.
• Psychologically, contact with the outside through a window, for example, produces an increase in well-being.
• Glare from natural lighting is tolerable.

Thus, it would not make much sense to buy a lamp with a colour temperature of 1000 K and turn it on in the morning, considering that its reddish tone is similar to that of a match. It is also not advisable to have an 8000 K bulb (very bluish) at night, no matter how good it looks. Its bluish light will prevent the release of melatonin, making it difficult to relax.

The light that comes from electronic devices is also lighting

A source of light that we tend to forget, perhaps because it wasn't designed to illuminate our surroundings, is the light from the screens on electronic devices. And yet we have all used the blue light from mobile screens to find our way in the dark. This is because the LED technology in lighting is identical to the LED technology of the screens in mobiles, tablets and computers.

The LED is a great ally in energy saving, but it doesn't always help tired eyes. This is why it is best to have monitors that incorporate:

• low blue light technology (ultra-low blue light emission monitors), especially during the afternoon;
• eye care technology to avoid eye strain during long working hours;
• technology for adjusting brightness and colour to daylight, which allows the monitor's light to be modulated based on the circadian cycle.