Dust masks

These types of masks should be used for work activities that produce dust, mist and/or fumes/smoke. The filtering can be compared to that of a sieve. The finer the sieve, the better the filtering. The disadvantage of a very good filter is that the holes through which the user has to breathe are smaller. This means the user must put in more effort to breathe. In other words, breathing resistance is greater with a fine filter than a coarse filter.

Dust masks work on the principle of mechanical filtration, which means breathing becomes more difficult when the filter is saturated. If the user notices this, the filter must be replaced immediately.

The comfort levels of a mask can be increased on several levels by the addition of an exhalation valve:

• Reduction of the exhalation effort
• Reduction of the CO2 content in the mask
• Reduction of the temperature and humidity in the mask