By way of example, PPM means "areas per million". If you find out which the concentration of NO2text NO _2NO2​ is equal to 1 ppm, it signifies that if you're taking a "sample" of air and divide it into 1,000,000 pieces, one of them will consist of NO2textual content NO https://zionaecxt.acidblog.net/67703152/the-basic-principles-of-free-ppm-calculator