According to the U.S. Department of Labor (www.msha.gov)
Mine Safety & Health Administration Title 30 Code of Federal Regulations (CFR § 77.170)
First aid equipment; location; minimum requirement:
(A) Each operator of a surface coal mine shall maintain a supply of the first aid equipment set forth in paragraph (B) of this section at or near each working place where coal is being mines, at each preparation and at shops and other surface installations where ten or more persons are regularly employed.
(B) The first aid equipment required to be maintained under the provisions of paragraph (A) of this section shall include at least the following:
(C) All first aid supplies required to be maintained under the provisions of paragraphs (A) and (B) of this section shall be stored in a suitable, sanitary, dust tight, moisture-proof container and such supplies shall be accessible to the miners.