Numerous amendments to definitions and scope of application of the principal Act. The Act shall apply to persons up through the end of their 18th year; children are defined as persons to the end of their 15th year, or to the end of their obligation to attend school. Allows children to work in family enterprises and enables local officials to permit child work in certain entertainment productions. Youths under 15 who are attending work training programmes may work no more than 35 hours per week during periods where there is no school. Young workers shall have two consecutive days off during the week, including a Sunday; youths who work on a Saturday shall have the following Saturday free. Also amends provisions concerning the use of machinery and dangerous substances by young workers, and provisions of the General Social Insurance Act regarding insurance for apprentices.