A work permit in regular form signed by a duly authorized officer, for all minors under 16 years of age, is conclusive evidence of age and educational attainment, in behalf of the employer of any minor, upon any prosecution for violation of the law relating to the employment of minors. An inspector of factories, attendance officer or other officer charged with the enforcement of this subchapter may make demand on any employer in or about whose place or establishment a minor apparently under the age of 16 years is employed, permitted or suffered to work, that such employer shall either furnish the inspector within 10 days documentary evidence of age as specified in section 775, or shall cease to employ, permit or suffer such minor to work in such place or establishment.   [PL 1991, c. 544, §9 (AMD).]