Screen-wash in summer
You may think that screen-wash is suitable in winter only, where it keeps you on the right side of the law, by ensuring that your windscreen washers work in freezing conditions. While the presumption is correct, screen wash also has its uses in the summer months, too.
As screen wash tends to be used less in the summer months, the solution is at greater risk of stagnation within the water bottle. Legionnaires’ disease, associated with ill-maintained water storage systems (including screen-wash bottles), occurs when a fine mist of contaminated water is breathed-in. Its bacteria thrives between 20 and 50 degrees Celsius, temperatures that are common within the screen wash bottle during the summer months. It is thought that a screen-wash additive helps to either kill the bacteria, or inhibits their reproduction.
Performance and safety advantages
The demands on summer screen-wash differ to those types used in winter. Several companies, therefore, have developed summertime additives that forgo anti-freezing properties in favour of being more effective at removing grease and dried-on insect residues, for example. This also helps to reduce the risk of glare. Therefore, do not consider summer screen-wash mixes as an unnecessary rip-off.