Volatile organic concentration
Volatile organic concentration or VO concentration means the fraction by weight of the volatile organic compounds contained in a hazardous secondary material expressed in terms of parts per million as determined by direct measurement or by knowledge of the material in accordance with the requirements of 261.1084 of this subpart. For the purpose of determining the VO concentration of a hazardous secondary material, organic compounds with a Henry's law constant value of at least 0.1 mole-fraction-in-the-gas-phase/mole-fraction-in the liquid-phase (0.1 Y/X) (which can also be expressed as 1.8 106atmospheres/gram-mole/m 3) at 25 degrees Celsius must be included.
40 CFR § 261.1081
As used in this subpart, all terms not defined herein shall have the meaning given to them in the Resource Conservation and Recovery Act and parts 260 through 266 of this chapter.