A modular powered air purifying respirator (PAPR) which is comprised of a fan, motor, scroll, and power source mounted within one housing, and which accepts either traditional or conformal filters. Ambient air is drawn into the PAPR module through the attached filter by a fan, which is driven by direct connection to a motor. The pressurized air is then accelerated by an optimized scroll to the outlet in the PAPR housing. The PAPR module can be employed in multiple use configurations. The PAPR module further comprises a removable battery pack module that is easily retained to/removed from the PAPR module, enabling a user to be able to quickly remove a spent battery pack module and install a fresh battery pack module, thereby replacing the batteries within one breath cycle.