One example is, PPM implies "areas for each million". If you find out the focus of NO2text NO _2NO2​ is equivalent to 1 ppm, it implies that if you take a "sample" of air and divide it into 1,000,000 components, one of these will encompass NO2text NO _2NO2​. Rijk is https://onlineppmcalculator86284.ivasdesign.com/57926918/a-simple-key-for-online-ppm-calculator-unveiled