# Threshold planning quantity (TPQ) for a non-reactive extremely hazardous substance (EHS) solid handled both as a solution and as a powder

How does a facility apply the threshold planning quantity (TPQ) for a non-reactive extremely hazardous substance (EHS) solid that is handled both as a solution and as a powder?

Facilities that handle both the powdered and solution forms of a particular non-reactive solid EHS will have to consider the quantities of each form and the particle size of the powder to determine whether they exceed the TPQ. Below are several examples of how to apply the TPQ methods for an unspecified non-reactive solid EHS that has a lower TPQ of 500 pounds and a higher TPQ of 10,000 pounds. In each of the examples below, the number of pounds of non-reactive EHS solid in solution represents the pounds of the solid only and not other components of the solution.Non-reactive EHS solid in solution exceeds 500 pound lower TPQ, powder (>100 microns) less than 10,000 pound TPQ. A facility has on-site 3,150 pounds of a non-reactive EHS solid in solution. They also have 5,000 pounds of the same pure non-reactive EHS powder with a particle size equal to or greater than 100 microns, which is less than the 10,000 pound TPQ. Multiplying the 3,150 pounds of solid EHS in solution by 0.2 equates to 630 pounds, which exceeds the lower TPQ of 500 pounds. Thus, the facility must report under section 302 of EPCRA based on exceeding the lower TPQ for the non-reactive EHS solid in solution form.

Non-reactive EHS solid in solution less than 500 pounds lower TPQ, powder (>100 microns) exceeds 10,000 pounds TPQ. A facility has on-site 1,800 pounds of a non-reactive EHS solid in solution. They also have 11,000 pounds of the same pure non-reactive EHS solid powder with a particle size equal to or greater than 100 microns, which is more than the 10,000 pound TPQ. Multiplying the 1,800 pounds of solid EHS in solution by 0.2 equates to 360 pounds, which is less than the lower TPQ of 500 pounds. The facility must report under section 302 of EPCRA based on exceeding the 10,000 pound TPQ for the solid EHS in powder form.

Non-reactive EHS solid in solution less than 500 pound lower TPQ, powder (>100 microns) less than 10,000 pound TPQ. A facility has 2,025 pounds of a non-reactive EHS solid in solution. They also have 5,000 pounds of the same pure non-reactive EHS solid powder with a particle size equal or greater than 100 microns, which is less than the 10,000 pound TPQ. Multiplying the 2,025 pounds of solid EHS in solution by 0.2 equates to 405 pounds, which is less than the lower TPQ of 500 pounds. Thus, the facility is not required to report under section 302 of EPCRA because it does not exceed the lower 500 pound TPQ for the non-reactive solid EHS in solution form or the 10,000 pound TPQ for the powder form with a particle size greater than 100 microns.

Non-reactive EHS solid in solution less than 500 pound TPQ and powder (<100 microns) less than 500 pound TPQ. A facility has 600 pounds of a non-reactive EHS solid in solution. They also have 400 pounds of the same non-reactive solid EHS in powder form with particle size less than 100 microns. Therefore, the lower TPQ of 500 pounds applies to both forms. The facility would multiply the 600 pounds in solution times 0.2, which equals 120 pounds. Adding 120 pounds to 400 pounds equals 520 pounds, which exceeds the 500 pound TPQ. Therefore, the facility would be required to report under section 302 of EPCRA.

Non-reactive EHS solid powder (<100 microns) less than 500 pound TPQ, processed into solution. A facility has 450 pounds of pure non-reactive solid EHS in powder form with particle size less than 100 microns (lower TPQ of 500 pounds applies). The same powder is then subsequently processed into a solution. The facility does not exceed the 500 pound TPQ based on the powder form. For the solution form, 450 pounds in solution multiplied times 0.2 equals 90 pounds, which also does not exceed the 500 pound TPQ. Therefore, the facility does not have to report for the solid EHS under section 302 of EPCRA.

Although the 500 pound TPQ applies to both powder and solution form in this example, the facility should not add together the pounds of powder form and the pounds of solid in solution multiplied by 0.2, to compare to the 500 pound TPQ, because the combined quantity does not represent the amount of the solid EHS present on-site at any one time. That is, the same quantity is not in powder form and in solution form at the same time. The facility is only required to report under section 302 of EPCRA if either the amount of non-reactive powder (<100 microns) or solid EHS in solution present at any one time exceeds the lower 500 pound TPQ.

Non-reactive EHS solid powder (<100 microns) exceeds 500 pound TPQ, processed into solution. A facility has 2000 pounds of pure non-reactive solid EHS in powder form with particle size less than 100 microns (lower TPQ of 500 pounds applies). The same powder is then subsequently processed into a solution. The facility exceeds the 500 pound TPQ based on the powder form. The subsequently processed 2000 pounds of non-reactive solid EHS in solution multiplied by 0.2 equals 400 pounds, which does not exceed the 500 pound TPQ. Because facility has more than 500 pounds on-site at one time of the solid EHS in powder form of less than 100 micron particle size, it is required to report under section 302 of EPCRA.

Non-reactive EHS solid powder (>100 microns) less than 10,000 pound TPQ, processed into solution. A facility has 3000 pounds of pure non-reactive solid EHS in powder form with particle size greater than 100 microns (TPQ of 10,000 pounds applies). This same powder is then subsequently processed into a solution (lower TPQ of 500 pounds applies). The facility does not exceed the 10,000 pound TPQ based on the powder form of greater than 100 microns. The subsequently processed 3000 pounds of non-reactive solid EHS in solution multiplied by 0.2 equals 600 pounds, which exceeds the 500 pound TPQ applicable for the solution form. Because facility has more than 500 pounds on-site at one time of the solid EHS in solution form, it is required to report under section 302 of EPCRA.