Method and apparatus for pressurizing a protective hood enclosure with exhaled air

A multiple zone protective enclosure comprising:

• an air-impermeable hood;
• said air-impermeable hood adapted to receive a wearer's head;
• said air-impermeable hood having a closed first end and an open second end;
• an air-impermeable transparent viewing area integrated into said air-impermeable hood, said air-impermeable transparent viewing area adapted to permit outward vision by said wearer;
• a first substantially airtight seal having a predetermined resistance to airflow, having an outer peripheral edge secured to said second end of said air-impermeable hood and having an inner peripheral edge adapted to sealingly engage a wearer's neck;
• said inner peripheral edge of said first substantially airtight seal adapted to sealingly engage said wearer's neck along a first annular line of contact and said inner peripheral edge of said second substantially airtight seal adapted to sealingly engage said wearer's neck along a second annular line of contact, said first and second annular lines of contact being disposed in vertically spaced apart relation to one another when said hood encloses the head of said wearer;
• a protection zone adapted to enclose the head of said wearer;
• said protection zone being defined by said air-impermeable hood and said first substantially airtight seal;
• an air-impermeable seal column depending from said second end of said air-impermeable hood, said air-impermeable seal column having a first end a second end;
• an outer peripheral edge of said second substantially airtight seal being secured to said second end of said seal column and having an inner peripheral edge adapted to sealingly engage a wearer's neck;
• a purge zone being defined between said first and second substantially airtight seals;
• a respiration interface having an inhalation pathway and an exhalation pathway, said inhalation pathway adapted to receive purified air through a particle filtration filter and said exhalation pathway adapted to dispatch exhaled air;
• an exhalation conduit disposed in fluid communicating relation between said exhalation pathway and said purge zone;
• said first and second substantially airtight seals providing a substantially universal fit;
• whereby when said first predetermined resistance to airflow of said first substantially airtight seal is greater than said second predetermined resistance to airflow of said second substantially airtight seal, exhaled air intermittently flows into said purge zone until a predetermined threshold pressure is reached, whereupon said exhaled air flows into ambient by overcoming the sealing power of said second substantially air tight seal;
• whereby when said first predetermined resistance to airflow of said first substantially airtight seal is substantially equal to said second predetermined resistance to airflow of said second substantially airtight seal, exhaled air intermittently flows into said purge zone until a predetermined threshold pressure is reached, whereupon said exhaled air flows in substantially equal amounts into said protective zone and to ambient by substantially simultaneously overcoming said first and second predetermined resistances to airflow of said first and second substantially air tight seals;
• and
• whereby when said first predetermined resistance to airflow of said first substantially airtight seal is less than said second predetermined resistance to airflow of said second substantially airtight seal, exhaled air intermittently flows into said purge zone until a predetermined threshold pressure is reached, whereupon said exhaled air flows into said protection zone, thereby pressurizing said protection zone, until pressure is equalized on opposite sides of said first substantially airtight seal so that subsequent exhalations cause exhaled air to flow out of the purge zone into ambient.

A multiple zone protective enclosure comprising:

• an air-impermeable hood;
• said air-impermeable hood adapted to receive a wearer's head;
• said air-impermeable hood having a closed first end and an open second end;
• an air-impermeable transparent viewing area integrated into said air-impermeable hood, said air-impermeable transparent viewing area adapted to permit outward vision by said wearer;
• a first substantially airtight seal having a predetermined resistance to airflow, having an outer peripheral edge secured to said second end of said air-impermeable hood and having an inner peripheral edge adapted to sealingly engage a wearer's neck;
• a second substantially airtight seal having an outer peripheral edge secured to said second end of said air-impermeable hood and having an inner peripheral edge adapted to sealingly engage said wearer's neck;
• said inner peripheral edge of said first substantially airtight seal adapted to sealingly engage said wearer's neck along a first annular line of contact and said inner peripheral edge of said second substantially airtight seal adapted to sealingly engage said wearer's neck along a second annular line of contact, said first and second annular lines of contact being disposed in vertically spaced apart relation to one another when said hood encloses the head of said wearer;
• a protection zone adapted to enclose the head of said wearer;
• said protection zone being defined by said air-impermeable hood and said first substantially airtight seal;
• an air-impermeable seal column depending from said second end of said air-impermeable hood, said air-impermeable seal column having a first end and a second end, and said first substantially airtight seal being pre-sealed to said first end of said seal column, said second substantially airtight seal being pre-sealed to said second end of said seal column;
• an outer peripheral edge of said second substantially airtight seal being secured to said second end of said seal column and having an inner peripheral edge adapted to sealingly engage said wearer's neck;
• a modular purge zone being defined between said first and second substantially airtight seals;
• a respiration interface having an inhalation pathway and an exhalation pathway, said inhalation pathway adapted to receive purified air through a particle filtration filter and said exhalation pathway adapted to dispatch exhaled air;
• an exhalation conduit disposed in fluid communicating relation between said exhalation pathway and said purge zone;
• said first and second substantially airtight seals providing a substantially universal fit;
• whereby when said first predetermined resistance to airflow of said first substantially airtight seal is greater than said second predetermined resistance to airflow of said second substantially airtight seal, exhaled air intermittently flows into said purge zone until a predetermined threshold pressure is reached, whereupon said exhaled air flows into ambient by overcoming the sealing power of said second substantially air tight seal;
• whereby when said first predetermined resistance to airflow of said first substantially airtight seal is substantially equal to said second predetermined resistance to airflow of said second substantially airtight seal, exhaled air intermittently flows into said purge zone until a predetermined threshold pressure is reached, whereupon said exhaled air flows in substantially equal amounts into said protective zone and to ambient by substantially simultaneously overcoming said first and second predetermined resistances to airflow of said first and second substantially air tight seals;
• and
• whereby when said first predetermined resistance to airflow of said first substantially airtight seal is less than said second predetermined resistance to airflow of said second substantially airtight seal, exhaled air intermittently flows into said purge zone until a predetermined threshold pressure is reached, whereupon said exhaled air flows into said protection zone, thereby pressurizing said protection zone, until pressure is equalized on opposite sides of said first substantially airtight seal so that subsequent exhalations cause exhaled air to flow out of the purge zone into ambient.

A method of using exhaled air to inflate a protective hood comprising the steps of:

• enclosing the head of a wearer with an air-impermeable hood having a closed first end and an open second end;
• integrating an air-impermeable transparent viewing area into said air-impermeable hood, said air-impermeable transparent viewing area adapted to permit outward vision by said wearer;
• creating a protection zone for the eyes, nose, and mouth of said wearer by providing a first substantially airtight seal and securing an outer peripheral edge of said first substantially airtight seal to said second end of said air-impermeable hood and by adapting an inner peripheral edge of said first substantially airtight seal to sealingly engage a neck of said wearer along a first annular line of contact;
• creating a first purge zone by providing a second substantially airtight seal and securing an outer peripheral edge of said second substantially airtight seal to said second end of said air-impermeable hood and by adapting an inner peripheral edge of said second substantially airtight seal to sealingly engage a neck of said wearer along a second annular line of contact;
• positioning said first and second annular lines of contact in vertically spaced apart relation to one another when said hood encloses the head of said wearer so that said first purge zone is adjacent said protection zone and so that said first substantially airtight seal separates said protection zone from said first purge zone;
• engaging a respiration interface to the respiratory system of said wearer, said respiration interface having an inhalation pathway adapted to receive purified air and an exhalation pathway adapted to dispatch exhaled air;
• connecting an exhalation conduit having a one-way check valve means adapted to restrict the flow of exhaled air only from said exhalation pathway to said first purge zone;
• and
• whereby exhaled air flows through said exhalation conduit into said first purge zone, increasing the air pressure within said first purge zone until air, following the path of least resistance, is forced through said first substantially airtight seal into said protection zone;
• whereby when said first predetermined resistance to airflow of said first substantially airtight seal is greater than said second predetermined resistance to airflow of said second substantially airtight seal, exhaled air intermittently flows into said first purge zone until a predetermined threshold pressure is reached, whereupon said exhaled air flows into ambient by overcoming the sealing power of said second substantially air tight seal;
• whereby when said first predetermined resistance to airflow of said first substantially airtight seal is substantially equal to said second predetermined resistance to airflow of said second substantially airtight seal, exhaled air intermittently flows into said first purge zone until a predetermined threshold pressure is reached, whereupon said exhaled air flows in substantially equal amounts into said protective zone and to ambient by substantially simultaneously overcoming said first and second predetermined resistances to airflow of said first and second substantially air tight seals;
• and
• whereby when said first predetermined resistance to airflow of said first substantially airtight seal is less than said second predetermined resistance to airflow of said second substantially airtight seal, exhaled air intermittently flows into said first purge zone until a predetermined threshold pressure is reached, whereupon said exhaled air flows into said protection zone, thereby pressurizing said protection zone, until pressure is equalized on opposite sides of said first substantially airtight seal so that subsequent exhalations cause exhaled air to of the first purge zone into ambient.

A multiple zone protective enclosure comprising:

• an air-impermeable hood;
• said air-impermeable hood adapted to receive a wearer's head and torso;
• said air-impermeable hood having a closed first end and an open second end;
• an air-impermeable transparent viewing area integrated into said air-impermeable hood, said air-impermeable transparent viewing area adapted to permit outward vision by said wearer;
• a first substantially airtight seal having an outer peripheral edge secured to said second end of said air-impermeable hood and having an inner peripheral edge adapted to sealingly engage a wearer's torso;
• a second substantially airtight seal having an outer peripheral edge secured to said second end of said air-impermeable hood and having an inner peripheral edge adapted to sealingly engage a wearer's torso;
• said inner peripheral edge of said first substantially airtight seal adapted to sealingly engage said wearer's torso along a first annular line of contact and said inner peripheral edge of said second substantially airtight seal adapted to sealingly engage said wearer's torso along a second annular line of contact, said first and second annular lines of contact being disposed in vertically spaced apart relation to one another when said hood encloses the head and torso of said wearer;
• a protection zone adapted to enclose the head and torso of said wearer, said protection zone being defined by said air-impermeable hood and said first substantially airtight seal, said protection zone adapted to surround said head and torso of said wearer;
• a purge zone defined between said first and second substantially airtight seals, said purge zone adapted to encircle said torso of said wearer;
• a respiration interface having an inhalation pathway and an exhalation pathway, said inhalation pathway adapted to receive purified air and said exhalation pathway adapted to dispatch exhaled air;
• an exhalation conduit disposed in fluid communicating relation between said exhalation pathway and said purge zone;
• said first and second substantially airtight seals providing a substantially universal fit;
• whereby when said first predetermined resistance to airflow of said first substantially airtight seal is greater than said second predetermined resistance to airflow of said second substantially airtight seal, exhaled air intermittently flows into said purge zone until a predetermined threshold pressure is reached, whereupon said exhaled air flows into ambient by overcoming the sealing power of said second substantially air tight seal;
• whereby when said first predetermined resistance to airflow of said first substantially airtight seal is substantially equal to said second predetermined resistance to airflow of said second substantially airtight seal, exhaled air intermittently flows into said purge zone until a predetermined threshold pressure is reached, whereupon said exhaled air flows in substantially equal amounts into said protective zone and to ambient by substantially simultaneously overcoming said first and second predetermined resistances to airflow of said first and second substantially air tight seals;
• and
• whereby when said first predetermined resistance to airflow of said first substantially airtight seal is less than said second predetermined resistance to airflow of said second substantially airtight seal, exhaled air intermittently flows into said purge zone until a predetermined threshold pressure is reached, whereupon said exhaled air flows into said protection zone, thereby pressurizing said protection zone, until pressure is equalized on opposite sides of said first substantially airtight seal so that subsequent exhalations cause exhaled air to flow out of the purge zone into ambient.