Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 8292991 | Gas mask filter canister | David K. Friday, Wayne Ballantyne, Robert J. Puhala, David W. Pike | 2012-10-23 |
| 8262782 | Respirator filter canister | — | 2012-09-11 |
| 7311764 | Gas mask filter canister | David K. Friday, Wayne Ballantyne, Robert J. Puhala, David W. Pike | 2007-12-25 |
| 4951474 | Cryo-refrigeration system | Salvatore T. DiNovo, Roy S. Brown | 1990-08-28 |
| 4850199 | Cryo-refrigeration system | Salvatore T. DiNovo, Roy S. Brown | 1989-07-25 |
| 4534346 | Pressure swing cycle for the separation of oxygen from air | — | 1985-08-13 |
| 4342573 | Compact oxygen concentrator | Norman R. McCombs | 1982-08-03 |
| 4302224 | Compact oxygen concentrator | Norman R. McCombs | 1981-11-24 |