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