| Naics index | Naics index description |
|---|---|
| 238220 | Fire extinguisher installation |
| 238220 | Fire extinguisher installation and repair |
| 238220 | Fire sprinkler system installation |
| 238220 | Fireplace, natural gas, installation |
| 238220 | Fuel oil burner installation |
| 238220 | Furnace conversion (i.e., from one fuel to another) |
| 238220 | Furnace humidifier installation |
| 238220 | Furnace installation |
| 238220 | Furnace, forced air, installation |
| 238220 | Gas fitting contractor |