Todays EPA standards are measured in g/bhp-hr not PPM. I agree, how do you compare PPM to g/bhp-hr ? Press Release quote: “While it is difficult to compare these results with current EPA standards,” stated Frankie Fruge, Cyclone’s COO." 2010 standards are as follows: · PM – 0.01 g/bhp-hr · NOx – 0.20 g/bhp-hr · NMHC – 0.14 g/bhp-hr