In organic hazardous air pollutant
In organic hazardous air pollutant or in organic HAP service means that a piece of equipment either contains or contacts a fluid (liquid or gas) that is at least 5 percent by weight of total organic HAP's as determined according to the provisions of 63.180 of this subpart. The provisions of 63.180(d) of this subpart also specify how to determine that a piece of equipment is not in organic HAP service.
40 CFR § 63.161
All terms used in this subpart shall have the meaning given them in the Act and in this section as follows, except as provided in any subpart that references this subpart.