Good in theory
When the biological quality of liquids or surfaces is important for your organisation, a UV disinfection system is an essential link in the chain. However, it is not automatically true that all UV systems are disinfecting well. Many producers calculate the effectiveness of their system based on theory. The intensity of the lamp is multiplied with the to be treated volume and the flow (the amount of liquid passing through), the number derived from this is the average UV dose. But an average dose does not mean very much. This is due to the fact that part of the liquid is above average and part of it is below average. One part of the stream gets too little UV (which means the micro organisms simply survive) and part of the stream gets too much UV (which gives the micro organisms a lethal dose ten times over, when just once is enough). Good in theory doesn’t translate to good in practice.