Sections for every million (ppm) denotes the volume of units of the compound contained in 1,000,000 models of another compound. It is a ratio expressing the concentration of 1 compound within just A different and is also widely accustomed to measure the purity of h2o, air, meals items, plus more. https://rafaelpmljh.theideasblog.com/37271551/new-step-by-step-map-for-free-ppm-calculator