A system comprising: a personal protection respiratory device that defines a filtered air volume adjacent to the face of a wearer and comprises an exhalation valve , and an exhaust apparatus comprising a housing and a blower positioned inside the housing between an inlet and an outlet thereof and comprising a fan and a motor which drives the fan , the exhaust apparatus being connected to the personal protection respiratory device such that the inlet of the exhaust apparatus is releasably connected to the exhaustion valve situated on the respiratory device and such that the blower is in fluid connection with the exhalation valve , wherein the blower is responsive to the wearer's respiratory cycle to draw a substantial portion of the wearer's exhaled breath from the filtered air volume of the respirator device through the exhalation valve of the respirator device and pass the inlet of the exhaust apparatus and to expel the wearer's exhaled breath out through the outlet of the exhaust apparatus and thus to atmosphere, wherein the exhaust apparatus further comprises: a controller , a pressure sensor for sensing a pressure generated by the wearer's breathing cycle and sending a pressure signal indicative of the pressure to the controller , the controller being in communication with the pressure sensor and the blower , wherein the controller operates the blower in response to the pressure signal, and wherein, in response to the wearer's respiratory cycle, the blower operates throughout the wearer's exhale breath, or a substantial period thereof, and does not operate throughout the wearer's inhale breath, or a substantial period thereof. an exhaust apparatus comprising a housing and a blower positioned inside the housing between an inlet and an outlet thereof and comprising a fan and a motor which drives the fan , the exhaust apparatus being connected to the personal protection respiratory device such that the inlet of the exhaust apparatus is releasably connected to the exhaustion valve situated on the respiratory device and such that the blower is in fluid connection with the exhalation valve , wherein the blower is responsive to the wearer's respiratory cycle to draw a substantial portion of the wearer's exhaled breath from the filtered air volume of the respirator device through the exhalation valve of the respirator device and pass the inlet of the exhaust apparatus and to expel the wearer's exhaled breath out through the outlet of the exhaust apparatus and thus to atmosphere, wherein the exhaust apparatus further comprises: a controller , a pressure sensor for sensing a pressure generated by the wearer's breathing cycle and sending a pressure signal indicative of the pressure to the controller , the controller being in communication with the pressure sensor and the blower , wherein the controller operates the blower in response to the pressure signal, and wherein, in response to the wearer's respiratory cycle, the blower operates throughout the wearer's exhale breath, or a substantial period thereof, and does not operate throughout the wearer's inhale breath, or a substantial period thereof. a controller , a pressure sensor for sensing a pressure generated by the wearer's breathing cycle and sending a pressure signal indicative of the pressure to the controller , the controller being in communication with the pressure sensor and the blower , wherein the controller operates the blower in response to the pressure signal, and wherein, in response to the wearer's respiratory cycle, the blower operates throughout the wearer's exhale breath, or a substantial period thereof, and does not operate throughout the wearer's inhale breath, or a substantial period thereof. <EOS>