9. Ultraviolet (UV)

9.1 Introduction

For several decades, a physical disinfection process has been used in drinking water production: ultraviolet radiation.

The term UV is used for radiation in the electromagnetic spectrum with wavelengths between the visible and X-rays, i.e. from 100 to 400 nm.

Within this spectrum, we also distinguish several families classified alphabetically by decreasing wavelength UV-A/UV-B/UV-C... (see figure 27 ).

UV-C (200 to 280 nm) is the only germicide (destroying bacteria, viruses, fungi, algae...