A personal protection respiratory device (120; 420) that defines a filtered air volume in a filtered air cavity (240; 340; 440) adjacent to the face of a wearer and comprises at least one exhalation valve (226; 326; 426) and at least one inhalation valve (236; 336; 436), said inhalation and exhalation valves being one-way diaphragm valves; wherein the personal protection respiratory device further includes a powered apparatus (210; 310; 410) that is either permanently or releasably connected thereto, the powered apparatus comprising: a first air duct (214; 314; 414) in fluid connection with the at least one exhalation valve, a second air duct (212; 312; 412) in fluid connection with the at least one inhalation valve, a first blower (218; 318; 418) associated with the first air duct, and a second blower (219; 319; 419) associated with the second air duct, the first and second blowers (218, 219; 318, 319; 418, 419) for selectively directing air through the first and second ducts, respectively, and being responsive to the wearer's respiratory cycle so that, in use, the first blower draws a substantial portion of the breath exhaled by the wearer through the at least one exhalation valve and out through the first duct, and the second blower draws a substantial portion of the air inhaled by the wearer through the second duct and in through the at least one inhalation valve; wherein the first blower operates throughout the wearer's exhale breath, or a substantial period thereof, and does not operate throughout the wearer's inhale breath, and the second blower operates throughout the wearer's inhale breath, or a substantial period thereof, and does not operate throughout the wearer's exhale breath; and wherein the exhaust apparatus further comprises: a controller, a pressure sensor for sensing a parameter generated by the wearer's breathing cycle and sending a signal indicative of the parameter to the controller, the controller being in communication with the sensor and the first and second blower, wherein the controller operates the first and second blower in response to the signal, and wherein the parameter is pressure, the signal is a pressure signal and the pressure that is sensed is the pressure of the filtered air volume in the filtered air cavity of the personal protection respiratory device. a first air duct (214; 314; 414) in fluid connection with the at least one exhalation valve, a second air duct (212; 312; 412) in fluid connection with the at least one inhalation valve, a first blower (218; 318; 418) associated with the first air duct, and a second blower (219; 319; 419) associated with the second air duct, the first and second blowers (218, 219; 318, 319; 418, 419) for selectively directing air through the first and second ducts, respectively, and being responsive to the wearer's respiratory cycle so that, in use, the first blower draws a substantial portion of the breath exhaled by the wearer through the at least one exhalation valve and out through the first duct, and the second blower draws a substantial portion of the air inhaled by the wearer through the second duct and in through the at least one inhalation valve; wherein the first blower operates throughout the wearer's exhale breath, or a substantial period thereof, and does not operate throughout the wearer's inhale breath, and the second blower operates throughout the wearer's inhale breath, or a substantial period thereof, and does not operate throughout the wearer's exhale breath; and wherein the first blower operates throughout the wearer's exhale breath, or a substantial period thereof, and does not operate throughout the wearer's inhale breath, and the second blower operates throughout the wearer's inhale breath, or a substantial period thereof, and does not operate throughout the wearer's exhale breath; and a controller, a pressure sensor for sensing a parameter generated by the wearer's breathing cycle and sending a signal indicative of the parameter to the controller, the controller being in communication with the sensor and the first and second blower, wherein the controller operates the first and second blower in response to the signal, and wherein the parameter is pressure, the signal is a pressure signal and the pressure that is sensed is the pressure of the filtered air volume in the filtered air cavity of the personal protection respiratory device.