​Does Rain make the windows dirty after they have just been cleaned?
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In 60’s, 70’s or 80’s when many people had open log or coal fires, and chimneys were billowing out thick black smoke, it is conceivable that when it rained it would bring down some of those dirt particles and cause them to stick to the windows, perhaps that’s where the erroneous conclusion has come from that rain makes the windows dirty. But actually these days, with the ‘Clean Air Act 1993’, the air is much more clean than it was back then. There is considerably less chance that any particle will come down with the rain to make the windows dirty.
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Why can we be so convinced?
Please watch the short video by clicking the link below which will describe why Rain water is actually much more pure than you might think.
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(The following expression are mentioned in the video:-
TDS = “Total dissolved solids is a measure of the dissolved combined content of all inorganic and organic substances present in a liquid in molecular, ionized, or micro-granular (colloidal sol) suspended form. TDS are often measured in parts per million (ppm). TDS in water can be measured using a digital meter.”
PPM = “Parts per million is a unit which expresses a small amount of dimensionless quantities. Proportionally, parts per million represents one thousandth of a millilitre of something per litre of water, or one milligram of something per kilogram of soil.”