How much CO₂is allowed in the air in workrooms is a legal requirement. But do you need to have it measured by an expert?​

It is your job as an employer to guarantee good indoor air quality in the work areas. Prevention is the starting point here: proactively detecting and tackling the sources of pollution.

Exactly which preventive measures are needed is part of the risk analysis. It maps both the quality of the air supplied and the possible sources of pollution. Examples of the latter are heating systems, floor coverings, technical equipment or the presence of people and animals.

This can be done by means of a climate study: a visual inspection or a check of the installations, calculations and technical documents of the ventilation system. Regularly ask employees how they experience air quality in the workplace.

No, only when the risk analysis showsit to be necessary and meaningful. This is the case when the above check causes doubts or discussions. An expert will then take a measurement of the air circulation and/or the quality and effectiveness of your ventilation system.

Too high a concentration of CO₂ in the air is detrimental to the concentration and leads to headaches and sore throats. Read more about the impact of poor air quality on employee productivity and absenteeism.

In the past, the CO₂ concentration in workrooms was never allowed to exceed 800 parts per million (ppm). In other words, at least 30 m³ of fresh air had to be supplied per employee present each hour. In practice this often turned out to be unrealistic, especially in rooms where many employees are present at the same time. Moreover, in older buildings it is not so easy to enlarge the existing ventilation ducts - if there are any at all. Today the average CO₂ limit value is 900 ppm. Because you may only exceed this upper limit to a limited extent, you must supply at least 40 m³ of fresh air per hour per person present.

If you were able to remove or reduce most of the material sources of pollution yourself thanks to technical or organisational measures (removing carpets, moving the copier to another room, etc.), the amount of CO₂ in the air should not exceed 1200 ppm.In this case, the ventilation flow rate is at least 25 m³ of fresh air per hour per person. All you have to do then is eliminate the polluted indoor air resulting from human presence.

If your premises are not up to scratch, an action plan should ensure that indoor air quality improves in the foreseeable future. This lists the concrete measures to remedy the pollution in the short and long term. The action plan is part of your global prevention plan.

Please note: this exception does not apply to new buildings. These buildings must immediately meet the new standards.