Class T - Technology

Subclass T  - Technology ( general )

T  55 - 55.3  Industrial safety.  Industrial accident prevention.
T  58.5 - 58.64 Information technology
T  61 - 173.  Technical education.  Technical schools.
T 201 - 342.  Patents.  Trademarks.

T 385.        Computer Graphics.

Subclass TA - Engineering ( general ).  Civil engineering.

TA 164.       Bioengineering.
TA 165.       Engineering instruments, meters, etc.  Industrial instrumentation.
TA 166 - 167. Human engineering.
TA 168.       Systems engineering.
TA 170 - 171. Environmental engineering.
TA 197 - 198. Engineering meteorology.
TA 329 - 348. Engineering mathematics.  Engineering analysis.
TA 703 - 712. Engineering geology.  Rock mechanics.  Soil mechanics.  Underground construction.
TA 1501 - 1820.  Applied optics.  Photonics.

Subclass TC - Hydraulic engineering.  Ocean engineering.

Subclass TD - Environmental technology.  Sanitary engineering.

TD 1 - 1066.  Environmental technology.  Sanitary engineering.
TD 169 - 171.8. Environmental protection.

Subclass TE - Highway engineering.  Roads and pavements.

Subclass TF - Railroad engineering and operation.

TF 855 - 1277.  Electric railways.

Subclass TG - Bridge engineering.

TG 1 - 470.  Bridge engineering.

Subclass TH - Building construction.

TH 7005 - 7699.  Heating and ventilation.  Air conditioning.
TH 7700 - 7975.  Illumination.  Lighting.

Subclass TJ - Mechanical engineering and machinery.

TJ 1 - 1570.  Mechanical engineering and machinery.
TJ 163.13 - 163.25.  Power sources.
TJ 163.26 - 163.5.  Energy conservation.
TJ 751 - 805.  Miscellaneous motors and engines including gas, gasoline, diesel engines.
TJ 807 - 830.  Renewable energy sources.
TJ 950 - 1030.  Pneumatic machinery.

Subclass TK - Electrical engineering.  Electronics.  Nuclear engineering.

TK 301 - 399.  Electric meters.
TK 452 - 454.4.  Electric apparatus and materials.  Electric circuits.  Electric networks.
TK 1001 - 1841.  Production of electric energy or power.  Power plants.  Central stations.
TK 2000 - 2891.  Dynamoelectric machinery and auxiliaries including generators, motors, transformers.
TK 2896 - 2985.  Production of electricity by direct energy conversion.
TK 3001 - 3521.  Distribution or transmission of electric power.
TK 4001 - 4102.  Applications of electric power.
TK 4125 - 4399.  Electric lighting.
TK 4601 - 4661.  Electric heating.
TK 5101 - 6720.  Telecommunication including telegraphy, telephone, radio, radar, television.
TK 7885 - 7895.  Computer engineering.  Computer hardware.
TK 9900 - 9971.  Electricity for amateurs.  Amateur constructors' manuals.

Subclass TL - Motor vehicles.  Aeronautics.  Astronautics.

Subclass TN - Mining engineering.  Metallurgy.

TN 1 - 997.  Mining engineering.  Metallurgy.
TN 263 - 271.  Mineral deposits.  Metallic ore deposits.  Prospecting.
TN 275 - 325.  Practical mining operations.  Safety measures.
TN 400 - 580.  Ore deposits and mining of particular metals.
TN 600 - 799.  Metallurgy.
TN 799.5 - 948.  Nonmetallic minerals.

Subclass TP - Chemical technology.

TP 1 - 1185.         Chemical technology.
TP 155 - 156.        Chemical engineering.
TP 248.13 - 248.65.  Biotechnology.
TP 250 - 261.        Inducstrial electrochemistry.
TP 267.5 - 301.      Explosives and pyrotechnics.
TP 315 - 360.        Fuel.
TP 670 - 699.        Oils, fats, and waxes.
TP 690 - 692.5.      Petroleum refining.  Petroleum products.
TP 700 - 746.        Illuminating industries ( non-electric ).
TP 751 - 762.        Gas Industry.

Subclass TR - Photography.

Subclass TS - Manufactures.

Subclass TT - Handicrafts.  Arts and crafts.

Subclass TX - Home economics.

TX 1 - 1110.  Home economics.
TX 341 - 641. Nutrition.  Foods and food supply.
TX 642 - 840. Cookery.
TX 851 - 885. Dining-room service.

000.