Such as, PPM indicates "components for every million". If you discover out that the concentration of NO2text NO _2NO2​ is equivalent to 1 ppm, it ensures that if you take a "sample" of air and divide it into 1,000,000 pieces, one of these will encompass NO2text NO _2NO2​. Sections For https://onlineppmcalculator65062.kylieblog.com/37335283/the-smart-trick-of-online-ppm-calculator-that-nobody-is-discussing