§ 144. Posting of hours. 1. The employer shall make a schedule for all minors employed by the employer, setting forth the hours of beginning and stopping and the time allowed for meals, which shall be kept conspicuously posted in each establishment where such persons are employed.

A change in the schedule of hours worked by minors pursuant to the provisions of this chapter shall be allowed provided that the posted schedule reflects the change. Nothing herein shall be construed so as to affect the limitations on hours worked by such minors as set forth elsewhere in this chapter.

2. The presence of any person subject to this article at any hours other than those stated in the above notice, or the failure to post such notice, shall constitute prima facie evidence of a violation of this article.

3. Where a person is employed in two or more establishments on the same day or week, the total time of employment shall not exceed that allowed per day or week in a single establishment.

4. Exception. If the commissioner finds that because of the nature of the work in a factory it is practically impossible to fix the hours of work weekly in advance, he may upon an application stating facts showing the necessity therefor, grant a permit dispensing with the poster required by this section. In every factory operating under such a permit, a time book shall be kept in a form approved by the commissioner showing the name and addresses of all employees subject to this subdivision and the hours worked by each of them on each day. No person shall knowingly make or suffer to be made a false entry in any such time book. Such time book shall be kept for a period of six years and shall be available upon request of the commissioner at the place of employment. The permit shall be posted conspicuously in the factory, and the commissioner may revoke the permit for failure to comply with the provisions of this subdivision.