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e-CFR data is current as of March 2, 2021

Title 40Chapter ISubchapter JPart 355Subpart B → §355.15

Title 40: Protection of Environment
Subpart B—Emergency Planning

§355.15   Which threshold planning quantity do I use for an extremely hazardous substance present at my facility in solid form?

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:

(a) Use the lower TPQ from Appendices A and B of this part if the solid:

(1) Is in powdered form and has a particle size less than 100 microns;

(2) Is in solution;

(3) Is in molten form; or

(4) Meets the criteria for a National Fire Protection Association (NFPA) rating of 2, 3 or 4 for reactivity.

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.

(b) If the solid does not meet one of the criteria in paragraph (a) of this section, then the TPQ is 10,000 pounds.

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