Purified hydrogen peroxide gas microbial control methods and devices
The present invention relates to methods and devices for providing microbial control and/or disinfection/remediation of an environment. The methods generally comprise: generating a Purified Hydrogen Peroxide Gas (PHPG) that is substantially free of, e.g., hydration, ozone, plasma species, and/or organic species; and directing the gas comprising primarily PHPG into the environment such that the PHPG acts to provide microbial control and/or disinfection/remediation in the environment, preferably both on surfaces and in the air.
1. A method of microbial control comprising:
a) providing a flow of humid ambient air to a photocatalytic cell comprising a titanium dioxide catalyst;
b) irradiating said titanium dioxide catalyst with ultraviolet (UV) light to generate Purified Hydrogen Peroxide Gas (PHPG) that is free of hydration and comprises less than 0.1 ppm ozone;
c) directing said PHPG into an environment to maintain a PHPG concentration of between 0.005 parts-per-million (ppm) and 0.1 ppm and less than 0.1 ppm ozone; and
d) controlling said microbes.
2. The method of microbial control of claim 1 , wherein said PHPG is maintained between 0.02 ppm and 0.05 ppm.
3. The method of microbial control of claim 2 , wherein said PHPG comprises less than 0.015 ppm ozone.
4. The method of microbial control of claim 3 , wherein said microbe is a bacterium.
5. The method of microbial control of claim 3 , wherein said microbe is Staphylococcus aureus, Enterococcus faecalis, Clostridium difficile , or Geobacillus stearothermophilus.
6. The method of microbial control of claim 3 , wherein said microbe is a fungus.
7. The method of microbial control of claim 6 , wherein said fungus is Aspergillus niger.
8. The method of microbial control of claim 3 , wherein said microbe is a virus.
9. The method of microbial control of claim 8 , wherein said virus is a norovirus.
10. The method of microbial control of claim 3 , wherein said environment is an occupied area.
11. The method of microbial control of claim 10 , wherein said environment is a hospital.
12. The method of microbial control of claim 10 , wherein said environment is a school.
13. The method of microbial control of claim 10 , wherein said environment is an office.
14. The method of microbial control of claim 10 , wherein said environment is a home.
15. The method of microbial control of claim 1 , wherein said controlling comprises disinfecting a surface, killing airborne pathogens, or a reduction in microbes.
16. A method to control microbes in a hospital comprising:
a) generating Purified Hydrogen Peroxide Gas (PHPG) that is free of hydration and comprises less than 0.1 ppm ozone;
b) directing said PHPG into a hospital environment to maintain a PHPG concentration between 0.005 parts-per-million (ppm) and 0.1 ppm and less than 0.1 ppm ozone; and
c) controlling said microbes.
17. The method of claim 16 , wherein said microbe is a fungus, a virus, or a bacterium.
18. The method of claim 17 , wherein said microbe is an airborne microbe.
19. The method of microbial control of claim 16 , wherein said PHPG is maintained between 0.02 ppm and 0.05 ppm.
20. The method of claim 16 , wherein said PHPG comprises less than 0.015 ppm ozone.
21. The method of claim 17 , wherein said microbe is on a surface in said hospital environment.
22. The method of microbial control of claim 2 , wherein said UV light comprises a wavelength between 188 and 249 nanometers (nm).
23. A method of continuous microbial control comprising:
a) providing Purified Hydrogen Peroxide Gas (PHPG) that is free of hydration and comprises less than 0.1 part-per-million ozone;
b) directing said PHPG into an environment to maintain a concentration of between 0.01 parts-per-million (ppm) and 0.1 ppm and less than 0.1 ppm ozone.
24. The method of claim 23 , wherein said providing comprises simultaneously oxidizing water in gas form and reducing oxygen gas.
25. The method of claim 24 , wherein said oxidizing water and said reducing is performed using a photocatalytic process.