residential areas need fast response residential sprinklers. in the past standard spray sprinklers were allowed in order to get existing buildings retrofit with fire sprinklers.
It depends on the standard the project is using to design. If 13R, must use residential in the dwelling unit. You can have up to 4 QR sprinklers in the dwelling unit. If NFPA 13, you can do QR sprinklers in lieu of residential sprinklers. You will likely end up with larger pipe sizing.