222-G/222-F Comparison Chart

 

222-G

222-F

Structure Classification

I, II or III

Default is II

None

Basic Wind Speed

3-second gust

Fastest mile

Ice

Mandatory

Follows ASCE7-05 Escalates with height

Optional – 75% no ice wind pressure w/ uniform ½” ice

Exposure Category

B, C or D

Default is C

C

Topographic Category

1 to 5

Default is 1

1

Earthquake loading

Section 2.7

Ignore if Class I, Ss<1.00 or total seismic shear is less than 50% total wind shear for structure w/o irregularities

None

Climbing and Working Facility Classes

A or B

Default is B

None

Analysis

Feasibility and Rigorous

Analysis

Modification

Must be based on a rigorous analysis

No Requirement

Rigging

Rigging plan required Effect on tower must be evaluated

No Requirement