FOREWORD This addendum adds new definitions@ revises Sections 6 and 7@ and adds a new Section 8 with requirements specific to multifamily buildings. The changes in requirements account for unique features of multifamily buildings as compared to single-family buildings and include (1) adjusting the whole-building ventilation rate due to the fact that infiltration cannot be relied on for individual units in multifamily buildings; (2) provision of ventilation to common spaces and common parking garages@ which do not exist in single-family buildings; and (3) prevention of contaminant transfer from other units through walls or ducts. Note: In this addendum@ changes to the current standard are indicated in the text by underlining (for additions) and strikethrough (for deletions) unless the instructions specifically mention some other means of indicating the changes.