As　infectious　respiratory　diseases　are　highly　transmissible　through　the　air,　researchers　have　improved　traditional　total　volume　air　distribution　systems　to　reduce　the　risk　of　infection.　Multi-vent　module-based　adaptive　ventilation　(MAV)　is　a　novel　type　of　ventilation　that　facilitates　the　switching　of　inlets　and　outlets　to　suit　different　indoor　scenarios　without　changing　the　ductwork　layout.　However,　little　research　has　been　undertaken　to　evaluate　the　sizing　of　MAV　modules　and　selection　of　air　velocity,　both　of　which　are　related　to　the　efficiency　of　the　MAV　system　in　removing　contaminants　and　the　corresponding　level　of　protection　for　occupants　in　the　ventilated　room.　Therefore,　this　study　proposed　the　module-source　offset　ratio　(MSOR).　The　MSOR　is　based　on　the　size　of　the　MAV　module　and　its　distance　from　an　infected　occupant　to　inform　the　selection　of　the　optimal　MAV　module　parameters　accordingly.　Computational　fluid　dynamics　simulations　were　conducted　to　study　the　distribution　of　contaminants　in　a　two-person　office　equipped　with　MAV.　Discrete　phase　particles　were　used　to　model　the　respiratory　contaminants　from　the　infected　occupant,　and　contaminant　concentration　distributions　were　compared　under　four　MAV　air　distribution　layouts　and　three　module　sizes　considered　using　the　MSOR.　The　results　indicate　that　for　MAV　systems,　the　optimal　discharge　of　contaminants　can　be　achieved　when　the　line　of　outlets　is　located　directly　above　the　infected　occupant.　These　results　are　expected　to　inform　the　deployment　of　MAV　systems　to　reduce　the　risk　of　airborne　infection.　©　2023　IBPSA.All　rights　reserved.