1.1 This specification covers carbon steel girder rails of three classes based on type or type and weight, and chemistry defined as follows and in Table 1:

1.1.1 Unless otherwise specified by the purchaser, girder-guard rails shall be Class A.

1.1.2 Plain and grooved-girder rails under 135 lb/yd (67.1 kg/m) in weight shall be specified by the purchaser as either Class A or Class B.

1.1.3 Plain and grooved-girder rails of 135 lb/yd in weight and heavier shall be Class C, unless otherwise specified.

1.2 The values states in inch-pound units are to be regarded as the standard. The values given in parentheses are for information only.