Question: 1 ntu is equal to how much ppm?
Answer: Convert to Parts Per Million Define a conversion factor between the NTU reading and mg/l. For example, the turbidity meter may read 15 NTU and the concentration of the standard solution to yield this response may be 5 mg/l. The conversion factor would be 1 mg/l = 3 NTU = 1 ppm based on 1 mg/l = 1 ppm.