The U.S. Bureau of Mines-Michigan Technological University mine ventilation mainframe program was successfully adapted for execution in a personal computer (pc). The hardware requirement can be as modest as 256 kilobytes (kb) of random access memory (ram) and two floppy disk drives. A version compiled for a pc possessing 512 kb ram has arrays dimensioned to accommodate 512 separate mine airways and junctions, and it contains all the features and capabilities of the original version. It has successfully analyzed all the ventilation networks tested, including a very large commercial mine (404 airways, 237 junctions, and 5 fans). In all cases the pc version produced practically identical results as obtained from the mainframe computer. In all respects, the pc version performed the same as the mainframe version with the exception of execution speed. When a numerical coprocessor is employed, execution time can be reduced by more than 50 pct. As an aid to the user of the pc version, a data base management program was developed using a commercially available data base management language to automate data entry and management.