The interpretations of the law contained in this part are official
interpretations which may be relied upon as provided in section 10 of
the Portal-to-Portal Act of 1947. In addition, the Supreme Court has
recognized that such interpretations of this Act ``provide a practical
guide to employers and employees as to how the office representing the
public interest in its enforcement will seek to apply it'' and
``constitute a body of experience and informed judgment to which courts
and litigants may properly resort for guidance.'' Further, as stated by
the Court: ``Good administration of the Act and good judicial
administration alike require that the standards of public enforcement
and those for determining private rights shall be at variance only where
justified by very good reasons.'' (Skidmore v. Swift, 323 U.S. 134).
Some of the interpretations in this part are interpretations of
exemption provisions as they appeared in the original Act before
amendment in 1949, 1961, and 1966, which have remained unchanged because
they are consistent with the amendments. These interpretations may be
said to have congressional sanction because ``When Congress amended the
Act in 1949 it provided that pre-1949 rulings and interpretations by the
Administrator should remain in effect unless inconsistent with the
statute as amended. 63 Stat. 920.'' (Mitchell v. Kentucky Finance Co.,
359 U.S. 290; accord, Maneja v. Waialua, 349 U.S. 254.)
