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(i) containing by-product materials; and

(ii) resulting from the operation by a person or organization of a nuclear facility included within the definition of nuclear facility under clauses (i) or (ii) of subparagraph (b) below;

(b) "nuclear facility" means:

(i) any nuclear reactor;

(ii) any equipment or device designed or used for (x) separating the isotopes of uranium or plutonium, (y) processing or utilizing spent fuel, or (z) handling, processing or packaging waste;

(iii) any equipment or device used for the processing, fabricating or alloying of special nuclear material if at any time the total amount of such material in the custody of the Insured at such premises where such equipment or device is located consists of or contains more than 25 grams of plutonium or uranium 233 or combination thereof or more than 250 grams of uranium 235;

(iv) any structure, basin, excavation, premises or place prepared for storage or disposal of waste;

(c) "nuclear facility" includes the site on which any of the foregoing is located, all operations conducted on such site and all premises used for such operations;

(d) "nuclear reactor" means any apparatus designed or used to sustain nuclear fission in a self-supporting chain reaction or to contain a critical mass of fissionable material;

(e) with respect to injury or destruction of property, the word "injury" or "destruction" includes all forms of radioactive contamination of property or loss of the use thereof.

M. RADIOACTIVE CONTAMINATION (OUTSIDE U.S.)

Liability of whatsoever nature directly or indirectly caused by or contributed to by or arising from ionizing radiations or contamination by radioactivity outside the United States, its territories or possessions, Puerto Rico or the Canal Zone from any nuclear fuel or from any nuclear waste from the combustion, fission or fusion of nuclear fuel.