| SIC | Description
|
| 331 | Blast Furnace and Basic Steel Products |
3312 | Blast furnaces and steel mills |
3313 | Electrometallurgical products |
3315 | Steel wire and related products |
3316 | Cold finishing of steel shapes |
3317 | Steel pipe and tubes |
332 | Iron and Steel Foundries |
3321 | Gray and ductile iron foundries |
3322 | Malleable iron foundries |
3324 | Steel investment foundries |
3325 | Steel foundries, nec |
333 | Primary Nonferrous Metals |
3331 | Primary copper |
3334 | Primary aluminum |
3339 | Primary nonferrous metals, nec |
334 | Secondary Nonferrous Metals |
3341 | Secondary nonferrous metals |
335 | Nonferrous Rolling and Drawing |
3351 | Copper rolling and drawing |
3353 | Aluminum sheet, plate, and foil |
3354 | Aluminum extruded products |
3355 | Aluminum rolling and drawing, nec |
3356 | Nonferrous rolling and drawing, nec |
3357 | Nonferrous wiredrawing & insulating |
336 | Nonferrous Foundries (Castings) |
3363 | Aluminum die-castings |
3364 | Nonferrous die-casting exc. aluminum |
3365 | Aluminum foundries |
3366 | Copper foundries |
3369 | Nonferrous foundries, nec |
339 | Miscellaneous Primary Metal Products |
3398 | Metal heat treating |
3399 | Primary metal products, nec |