Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5356446 | Low density insulating and fire-resistant perlite concrete | David A. Smetana, Alfonzo L. Wilson, Said Dimitry | 1994-10-18 |
| 5302200 | Hydrating and plasticizing admixture for dense concrete | David A. Smetana, Alfonzo L. Wilson | 1994-04-12 |
| 5294255 | Pumpable backfill grout | David A. Smetana, Alfonzo L. Wilson | 1994-03-15 |