(1) The Montana standards for quality of individual shell eggs contained in this sub-chapter are applicable only to eggs that are the product of the domesticated chicken hen and in the shell.

(2) Interior egg quality specifications for these standards are based on the apparent condition of the interior contents of the egg as it is twirled before the candling light, except as otherwise provided in sub-chapter 3. Any type or make of candling light may be used that will enable the particular grader to make consistently accurate determination of the interior quality of shell eggs. It is desirable to break-out an occasional egg and by determining the Haugh unit value of the broken-out egg, compare the broken-out and candled appearance, thereby aiding in correlating candled and broken-out appearance.