Ionizing radiation for treatment of complete diets for animals may be safely used under the following conditions:

1. (a) Energy sources. Ionizing radiation is limited to:

   1. (1) Gamma rays for sealed units of the radionuclides cobalt-60 or cesium-137.
   2. (2) Electrons generated from machine sources at energy levels not to exceed 10 million electron volts.

2. (b) Uses.

   1. (1) The ionizing radiation is used or intended for use in single treatment as follows:

      Food for irradiation	Limitations	Use
      Bagged complete diets, packaged feeds, feed ingredients, bulk feeds, animal treats and chews	Absorbed dose: Not to exceed 50 kiloGrays. Feeds and feed ingredients treated by irradiation should be formulated to account for nutritional loss	Microbial disinfection, control or elimination

   2. (2) If an irradiated feed ingredient is less than 5 percent of the final product, the final product can be irradiated without being considered to be re-irradiated.

[51 FR 5993, Feb. 19, 1986; 51 FR 8315, Mar. 11, 1986, as amended at 58 FR 18148, Apr. 8, 1993; 66 FR 18540, Apr. 10, 2001]