Category
Environmental Science
All Nolege News articles on Environmental Science.
5 articles
Environmental Science
A virus is far smaller than the gaps in an N95. The mask catches it anyway, and it catches it better than a bigger particle
The argument that a mask cannot stop a virus because the virus is smaller than the holes assumes a filter is a sieve. It is not. Four separate capture mechanisms operate, and the size a filter struggles most with is in the middle — which is why very small particles are caught more easily than medium ones.
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Environmental Science
The old paint on your walls is probably harmless. Sanding it off is the dangerous part
India capped lead in household paint at 90 ppm in 2016. Anything painted before that may be far above it — and the exposure route is not the intact film on the wall, it is the dust released when somebody prepares the surface for repainting. Here is why the paint was leaded, who is actually at risk, and why leaving it in place is often the better answer.
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Environmental Science
Boiling concentrates fluoride rather than removing it. What actually takes it out is a metal oxide surface
Fluoride and arsenic in Indian groundwater pass straight through boiling, chlorination and every candle filter, because they are dissolved ions rather than particles or microbes. Here is what removes them, why arsenic must be oxidised first, and where 'nano' genuinely helps rather than merely appearing on the box.
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Environmental Science
Your phone says AQI 180 and the government board says 300. Both can be right.
The AQI is not a measurement. It is a formula applied to measurements, and knowing how the formula works explains why two apps disagree, why the number lags a bad evening by hours, and why 'satisfactory' is not the same as clean.
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Environmental Science
How a water treatment plant cleans water
Turning river water into safe drinking water is a sequence of deliberate steps, each removing something the previous one could not. Here is what happens between the intake and the tap, and why the order matters.
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