| Call Number | Subject |
|---|---|
| T | Technology (General) |
| TA | Engineering (General). Civil engineering |
| TC | Hydraulic engineering. Ocean engineering |
| TD | Environmental technology. Sanitary engineering |
| TE | Highway engineering. Roads & pavements |
| TF | Railroad engineering & operation |
| TG | Bridge engineering |
| TH | Building construction |
| TJ | Mechanical engineering & machinery |
| TK | Electrical engineering. Electronics. Nuclear engineering |
| TL | Motor vehicles. Aeronautics. Astronautics |
| TN | Mining engineering. Metallurgy |
| TP | Chemical technology |
| TR | Photography |
| TS | Manufactures |
| TT | Handicrafts. Arts & crafts |
| TX | Home economics |