A mezzanine addition does not require seismic strengthening of the entire building when all of the following conditions are met:

1. A. Entire building strengthening is not required by any other provision contained in this Title;
2. B. The net floor area of the of the proposed mezzanine addition is less than 1/3 of the net floor area of the building;
3. C. The mezzanine addition does not result in an occupant load increase, as defined by the OSSC, of more than 149 people; and
4. D. Subsections 24.85.050 A. - C. also applies to mezzanine additions.