Seismic design of staircase in California

I am designing a steel staircase located in South Long Beach, California. It is about 22' tall laid at about 40 deg to horizontal. To estimate seismic loads on the structure, I am considering it as a non-building structure subject to the sections of Chapter 15 of ASCE 7 (2005 edtition). There are 2 tables in this chapter to determine "R" and "Omega 0": Table 15.4-1 for nonbuilding structures similar to buildings and Table 15.4-2 for nonbuilding structures not similar to buildings.  I think the staircase would be classified under Table 15.4-2 as "All other self-suppoting structures, tanks or vessels not covered above or by reference standards that are similar to buildings". Under this classification R = 1.25 and Omega0=2. Is my assumption correct? If not, what will be the accepted method? Thanks. Rajendran