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(d) Seismic evaluation and design of soft, weak, or open-front wall conditions in multiunit residential buildings of wood construction in Occupancy Category I or II are permitted to be based on the procedures'specified in Chapter A4. (e) Seismic evaluation and design of concrete buildings in all Occupancy Categories are permitted to be based on the procedures specified in Chapter A5. (3) Compliance with ASCE 31 based on the applicable performance level as shown in Table 3405.6.2. It shall be permitted to use the BSE-1 earthquake hazard level as defined in ASCE 41 and subject to the limitations in item 4 below. (4) Compliance with ASCE 41 using the BSE-1 Earthquake Hazard Level defined in ASCE 41 and the performance level as shown in Table 3405.6.2. The design spectral response acceleration parameters Sxs and Sxl specified in ASCE 41shall not be taken less than 75 percent of the respective design spectral response acceleration parameters SDS and SDI as defined by the California Building Code and its reference standards. TABLE 3405.6.2 PERFORMANCE CRITERIA FOR REDUCED CBC LEVEL SEISMIC FORCES OCCUPANCY CATEGORY PERFORMANCE LEVEL PERFORMANCE LEVEL (BASED ON CBC FOR USE WITH ASCE 31 FOR USE WITH ASCE 41 TABLE 1604.5) BSE-1 EARTHQUAKE BSE-2 EARTHQUAKE HAZARD LEVEL HAZARD LEVEL I Life Safety(LS) Life Safety(LS) II Life Safety(LS) Life Safety(LS) III . Note (a),Note (b) Note (a) IV Immediate Occupancy(IO) Immediate Occupancy(IO) (a) Acceptance criteria for Occupancy Category III shall be taken as 80 percent of the acceptance criteria specified for Occupancy Category II performance levels, but need not be less than the acceptance criteria specified for Occupancy Category IV performance levels. (b) For Occupancy Category III, the ASCE screening phase checklists shall be based on the life safety performance level. Ordinance 558 Page 7