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Radiation Protection

Subpart K: National Emission Standards for Radionuclide Emissions From Elemental Phosphorus Plants

Rule Summary

Subpart K protects the public and the environment from the emission of radioactive polonium-210 to the ambient airHelpambient airThe air that surrounds us from phosphorus plants. The standard limits annual air emissions of polonium-210 to two curies of polonium-210 for certain processes.

Elemental phosphorus plants extract pure phosphorus from ore for use in the chemical industry. Phosphate ore contains uranium and its decay products, including polonium-210,  which could enter the atmosphere from the extraction process.  


Compliance is achieved by demonstrating that total polonium-210 emissions from the plant meet annual release limits set by the regulation. Except under certain conditions, owners or operators must test emissions annually and submit the results to EPA. 

All facilities subject to any NESHAP must meet 40 CFR Part 61, Subpart A: General Provisions.