The objective of this research was the development of test criteria for direct current (dc) fuses used for protecting trailing cables in coal mines. Using data developed in an earlier study, a preliminary set of requirements for such fuses was established. Interested parties such as fuse manufacturers, mining equipment manufacturers, and mine operators were contacted and asked to comment on the preliminary requirements. Fuses were tested using these peliminary requirements, and the viability and reasonableness of the test procedure were judged. A meeting of representatives of fuse manufacturers, a mine operator, the Mine Safety and Health Administration, and the contractors for phases I and II of this effort was held. From the information gained to that date and the comments made at the meeting, final proposed test criteria for mine duty fuses were established.