Issued Patents All Time
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5733515 | Purification of air in enclosed spaces | David T. Doughty, Richard A. Hayden, Thomas M. Matviya | 1998-03-31 |
| 5700436 | Purification of air in enclosed spaces | David T. Doughty, Richard A. Hayden, Thomas M. Matviya | 1997-12-23 |
| 5492882 | Chromium-free impregnated activated universal respirator carbon for adsorption of toxic gases and/or vapors in industrial applications | David T. Doughty, William J. Knebel | 1996-02-20 |