| # | Company name | Role | # of projects |
|---|---|---|---|
| 1 | C & H Fire Suppression Systems Inc | Fire protection engineering | 1 |
| 2 | Cadco Construction | Fire protection engineering | 1 |
| 3 | Cafco Europe S.A. | Fire protection engineering | 1 |
| 4 | Cafco International | Fire protection engineering | 1 |
| 5 | Calculated Fire Protection | Fire protection engineering | 0 |
| 6 | California Fire Protection | Fire protection engineering | 0 |
| 7 | California Industrial Sprinkler | Fire protection engineering | 0 |
| 8 | Cannon Fire Protection Co | Fire protection engineering | 0 |
| 9 | Capital Sprinkler | Fire protection engineering | 1 |
| 10 | Capitol Sprinkler Contracting Inc. | Fire protection engineering | 0 |
| 11 | Capsco Industries | Fire protection engineering | 1 |
| 12 | Cardel Fire Protection Inc. | Fire protection engineering | 1 |
| 13 | Carden Fire Protection | Fire protection engineering | 1 |
| 14 | Cardinal Fire Protection Inc. | Fire protection engineering | 0 |
| 15 | Caribbean Fire and Associates, Inc | Fire protection engineering | 2 |
| 16 | Carolina Fire Control | Fire protection engineering | 0 |
| 17 | Cascade Fire Protection | Fire protection engineering | 2 |
| 18 | Casteel Automatic Fire Protection | Fire protection engineering | 2 |
| 19 | Casteel Automatic Fire Protection | Fire protection engineering | 0 |
| 20 | Casteer Fire Protection | Fire protection engineering | 0 |