| 925.07 Air Conditioning, Heating and Ventilating Engineering |
| 925.08 Airports (Lighting, Fueling, Navaids) - Engineering |
| 925.31 Electrical Engineering (Incl. Cogeneration Design Services) |
| 925.33 Engineer Services, Professional |
| 925.36 Engineering Services (Not Otherwise Classified) |
| 925.37 Facilities Design Services, Engineering |
| 925.39 Fire Protection Engineering |