EHSs that are in solid form are subject to one of two different TPQs (for example, TPQs may be listed as 500/10,000 pounds), both of which are listed in Appendices A and B of this part. Here is how to determine which of the two listed TPQs you must use for an EHS present at your facility in solid form:
Note to paragraph (a): Use the instructions in § 355.16 to calculate the quantity present for the categories of solids listed in paragraphs (a)(1), (2) and (3) of this section.
40 C.F.R. §355.15