Artikel 4

1. All necessary measures, including the provision of appropriate penalties, shall be taken by the competent authority to ensure the effective enforcement of the provisions of this Convention.
2. Each Member which ratifies this Convention undertakes either to maintain an appropriate inspection service for the purpose of supervising the application of the provisions of the Convention or to satisfy itself that appropriate inspection is carried out.
3. National laws or regulations shall define the persons responsible for compliance with the provisions of this Convention.
4. The employer shall keep, and make available to inspectors, records containing, in respect of persons under 21 years of age who are employed or work underground
(a) the date of birth, duly certified wherever possible;
(b) an indication of the nature of their occupation; and
(c) a certificate which attests fitness for employment but does not contain medical data.
5. The employer shall make available to the workers' representatives, at their request, the information mentioned in paragraph 4 of this Article.