2. Choose a ventilation technique

Depending on the situation, you can call on two main types of installation:

• local ventilation, in which the pollutant is intercepted as close as possible to its point of emission;

• general ventilation, in which the pollutant is dispersed in the room before being evacuated by dilution; general ventilation can be natural – through – or mechanical.

Depending on the problem to be treated, you may opt for a combination of these techniques.

Your first choice should be local ventilation, which is generally more efficient and less energy-intensive.

However, depending on the pollutant's toxicity and emission characteristics (low, moderately toxic emissions at dispersed points, for example), general ventilation may offer an acceptable...