The procedure for calculating the net section factor for an angle section is as follows:

• For a channel section, net section factor is taken to be 1.0.

• For an angle section, it is the ratio of the net effective area, A_net, to the gross area, where:

  1. Single angle connected by only one leg

     Anet = A1 + A2 × K1

     where

     A1	=	net cross-sectional area of the connected leg
     A2	=	gross cross-sectional area of the unconnected leg
     K1	=	3·A1/(3·A1 + A2)

     The area of a leg of an angle = Thickness of angle × (length of leg – 0.5× thickness of leg)

  2. Pair of angles placed back-to-back connected by only one leg of each angle to the same side of a gusset plate

     Anet = A1 + A2 · K1

     where

     A1	=	net cross-sectional area of the connected leg
     A2	=	gross cross-sectional area of the unconnected leg
     K1	=	5·A1/(5·A1 + A2)

     The area of a leg of an angle = Thickness of angle × (length of leg – 0.5× thickness of leg)

  3. Double angles placed back-to-back and connected to each side of a gusset plate

     • A_net = gross area minus the deduction for holes