Question: 1 ppm is how many lb per lb?
Answer: ppm↔lbs/in3 1 lbs/in3 = 27679904.70291 ppm. ppm↔per 1 per = 10000 ppm. ppm↔ppb 1 ppm = 1000 ppb. ppm↔ppt 1 ppm = 1000000000 ppt.