**2.12 Pollution prevention principles**

As a human being we can prevent the occurrence of pollution before it happens and reduce consecutively its impact if it occurs. Pollution can be prevented at the source, path, and receiver (usually individuals). Prevention at source means avoiding pollution occurrence in the first place by either eliminating, banning, or restricting the usage of hazardous chemicals at commercial levels. Pollution prevention at the path includes proper ventilation of living rooms which is expressed in terms of window floor ratio. Finally, prevention at the receiver can be using personal protective equipment like wearing masks where the concentration of pollutants is higher.
