| Naics index | Naics index description |
|---|---|
| 541320 | Town planning services |
| 541320 | Urban planners' offices |
| 541320 | Urban planning services |
| 541330 | Acoustical engineering consulting services |
| 541330 | Acoustical system engineering design services |
| 541330 | Audio visual system engineering design services |
| 541330 | Boat engineering design services |
| 541330 | Chemical engineering services |
| 541330 | Civil engineering services |
| 541330 | Combustion engineering consulting services |