The codes below display in the CL: Classification field.

Each classification code begins with one of the following letters, indicating the type of material discussed in the record:

S: Steels
G: Nonferrous Metals
P: Polymers
C: Ceramics
D: Composites

Each classification code also contains a number, indicating the topical coverage of the record. The number codes are as follows:

1 Fuel, Energy Usage, Raw Materials, Recycling
2 Plant Development and Descriptions
3 Engineering, Control and Testing, Machinery
4 Environmental Issues, Waste Treatment, Health and Safety
5 Product and Process Developments
6 Applications, Competitive Materials, Substitution
7 Management, Training, Regulations, Marketing
8 Economics, Statistics, Resources and Reserves
9 World Industry News, Company Information, General Issues

For example, a record on applications of composite materials would have the following content in its CL field:

D6 Applications, Competitive Materials, Substitution

To recall records with a given classification code, only the letter and the number are needed. For example, to search by classification code for records on environmental issues involving steels, enter

cl=s4

To search for records on environmental issues involving nonferrous metals, enter

cl=g4