| HT- 1 | Heat Treatment of Aluminum Alloys | Heat Treat |
| Supercedes: None | Superceded By: None |
| Number | Name | State | Country |
| 90067803 | Align Precision 526 NORTH AVIATION WAY | UT | United States |
| 90024576 | Astro Aluminum Treating Co. Inc. | CA | United States |
| 90051687 | Bodycote Thermal Processing - West Street | KS | United States |
| 90043216 | Bodycote Thermal Processing - Westminster | CA | United States |
| 90053657 | Valco Manufacturing Company | OK | United States |