At the end of the 19th century English scientists Arthur Downs and Thomas Blunt noticed, that micro-organisms (viruses, spores, bacteria, mould, fungi) do not reproduce when exposed to
sunlight. Later it was recognized that there is a specific wavelength dependency with a reaction maximum 253.7 nm. The reason is in the fact that the UV is absorbed by the DNA in micro-organisms
(or the RNA in certain viruses) and causes a disruption in the structure of these large molecules. These structural changes make it impossible for the micro-organisms to replicate, and hence no
infection is possible. Generally speaking srerilization is a process whereby vegetative and spore forms of micro-organisms are destroyed both physically and chemically. Physical destruction may be
achieved through high temperatures ,ultra-violet or infra-red radiation or ultra-sound waves.Chemical sterilization is achieved with the help of gases and various solutions of chemical
substances.
Although it is not as effective as the impact of high temperature(steam or hot air), ultra-violet sterilization is used widely in the home and workplace. Those ideas direct from nature are used in
various devices sterilizing the air, water and surfaces. The effect of this photochemical reaction depends on lamp power, exposure time and type of micro-organism. Simpler micro-organisms
need less radiation than more complicated ones. There is no need to explain why sterilization is important. Micro-organisms are everywhere. They are imperceptibly present in the air, water, food.
We breathe them in, eat and drink them and swim with them in the swimming pools. Our immune systems are constantly at war with them and not every time successfully. This is something we can do to
assist them.