Section 1613.3.5 - Determination of seismic design category <br />TABLE 1613.3.5(1) <br />SEISMIC DESIGN CATEGORY BASED ON SHORT-PERIOD (0.2 second) RESPONSE ACCELERATION <br />VALUE OF S <br />RISK CATEGORY <br />DI <br />I or II <br />III <br />IV <br />SDI < 0.167g <br />A <br />A <br />A <br />0.167g SDI < 0.33g <br />B <br />B <br />C <br />0.33g:5 SDI < 0.509 <br />C <br />C <br />D <br />0.509 SDI <br />D <br />D <br />D <br />For Risk Category = I and SDI = 0.607 g, Seismic Design Category = D <br />TABLE 1613.3.5(2) <br />SEISMIC DESIGN CATEGORY BASED ON 1-SECOND PERIOD RESPONSE ACCELERATION <br />VALUE OF S <br />RISK CATEGORY <br />DI <br />I or II <br />III <br />IV <br />SDI < 0.067g <br />A <br />A <br />A <br />0.0678 SDI < 0.133g <br />B <br />B <br />C <br />0.1338 SDI < 0.20g <br />C <br />C <br />D <br />0.208 SDI <br />D <br />D <br />D <br />For Risk Category = I and SDI = 0.427 g, Seismic Design Category = D <br />Note: When S, is greater than or equal to 0.758, the Seismic Design Category is E for <br />buildings in Risk Categories I, II, and III, and F for those in Risk Category IV, irrespective of <br />the above. <br />Seismic Design Category - "the more severe design category in accordance with <br />Table 1613.3.5(1) or 1613.3.5(2)" = D <br />Note: See Section 1613.3.5.1 for alternative approaches to calculating Seismic Design <br />Category. <br />References <br />1. Figure 1613.3.1(1): http://earthquake.usgs.gov/hazards/designmaps/downloads/pdfs/IBC-2012- <br />Fig1613p3p1(1).pdf <br />2. Figure 1613.3.1(2): http://earthquake.usgs.gov/hazards/designmaps/downloads/pdfs/IBC-2012- <br />Fig1613p3p1(2).pdf <br />