| # | Company name | Role | # of projects |
|---|---|---|---|
| 1 | H. Karloch | Fire protection engineering | 2 |
| 2 | H2o Fire Sprinkler Systems | Fire protection engineering | 1 |
| 3 | Hagen - Ingenieure für Brandschutz | Fire protection engineering | 2 |
| 4 | Hall & Kay Fire Engineering | Fire protection engineering | 5 |
| 5 | Hall Fire Protection Ltd. | Fire protection engineering | 1 |
| 6 | Hampshire Fire Protection | Fire protection engineering | 1 |
| 7 | Harrington Group | Fire protection engineering | 1 |
| 8 | Harroun Fire Protection | Fire protection engineering | 0 |
| 9 | Hart Engineering | Fire protection engineering | 4 |
| 10 | Harvey & Price Co. | Fire protection engineering | 1 |
| 11 | Haynes Fire Protection | Fire protection engineering | 0 |
| 12 | Hazard Fire Protection Engineering | Fire protection engineering | 1 |
| 13 | Heister + Ronkartz | Fire protection engineering | 1 |
| 14 | Hep Inc. | Fire protection engineering | 1 |
| 15 | HHP Hosser Hass + Partner Ingenieurgesellschaft mbH | Fire protection engineering | 9 |
| 16 | HHP Nord/Ost Beratende Ingenieure GmbH | Fire protection engineering | 4 |
| 17 | HHP Süd Beratende Ingenieure GmbH | Fire protection engineering | 4 |
| 18 | hhpberlin Ingenieurgesellschaft für Brandschutz mbH | Fire protection engineering | 28 |
| 19 | Highland Fire Protection | Fire protection engineering | 3 |
| 20 | hilla Sachverständigenbüro für vorbeugenden Brandschutz | Fire protection engineering | 5 |