General Order 95
Section IV
Strength Requirements for All Classes of Lines
48.2
Steel
The safety factors specified in Rule 44 shall be applied as follows to structural steel:
Tension and Bending: The yield point, 33,000 pounds per square inch, shall be divided by the safety factor to determine the maximum allowable working stress.
Compression: The maximum allowable working stress shall be calculated
by the following formula:
Where Smax = maximum allowable working stress, lbs per square inch
fs = safety factor specified in Rule 44
YP = yield point of the steel, 33,000 lbs. per sq. in.
l = unsupported length of member, inches
r = radius of gyration of member, inches
Shear: The ultimate tensile strength, 60,000 pounds per square inch, shall be multiplied by 2/3 and divided by the safety factor specified in Rule 44 to determine the maximum allowable working stress
Where American Society for Testing Materials (ASTM) A36-97 steel is used, the yield point shall be taken as 36,000 pounds per square inch (36ksi) and the tensile strength shall be taken as 58ksi. If other grades of steel are used, the yield point and ultimate strength used to calculate maximum working stress shall correspond to the minimum values specified in the appropriate ASTM specification for the grade of steel used.