(a) Specific exemptions from the child labor requirements of the Act are provided for:

(1) Employment of children in agriculture outside of school hours for the school district where they live while so employed;

(2) Employment of employees engaged in the delivery of newspapers to the consumer;

(3) Employment of children as actors or performers in motion pictures or in theatrical, radio, or television productions;

(4) Employment by a parent or a person standing in a parent's place of his own child or a child in his custody under the age of sixteen years in any occupation other than manufacturing, mining, or an occupation found by the Secretary to be particularly hazardous for the employment of children between the ages of sixteen and eighteen years or detrimental to their health or well-being.

(5) Employment of homeworkers engaged in the making of evergreen wreaths, including the harvesting of the evergreens or other forest products used in making such wreaths.

(6) Employment of 16- and 17-year-olds to load, but not operate or unload, certain scrap paper balers and paper box compactors under specified conditions.

(7) Employment of 17-year-olds to perform limited driving of cars and trucks during daylight hours under specified conditions.

(8) Employment of youths between the ages of 14 and 18 years who, by statute or judicial order, are excused from compulsory school attendance beyond the eighth grade, under specified conditions, in places of business that use power-driven machinery to process wood products.

(b) When interpreting these provisions, the Secretary will be guided by the principle that such exemptions should be narrowly construed and their application limited to those employees who are plainly and unmistakably within their terms. Thus, the fact that a child's occupation involves the performance of work which is considered exempt from the child labor provisions will not relieve his employer from the requirements of section 12(c) or the producer, manufacturer, or dealer from the requirements of section 12(a) if, during the course of his employment, the child spends any part of his time doing work which is covered but not so exempt.