Safe, Effective, and Cost-Efficient Air Cleaning for Populated Rooms and Entire Buildings Based on the Disinfecting Power of Vaporized Hypochlorous Acid
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 32845
Safe, Effective, and Cost-Efficient Air Cleaning for Populated Rooms and Entire Buildings Based on the Disinfecting Power of Vaporized Hypochlorous Acid

Authors: D. Boecker, R. Breves, F. Herth, Z. Zhang, C. Bulitta


Pathogen-carrying aerosol particles are recognized as important infection carriers like those in the current Corona pandemic. This infection route is often underestimated yet represents the infection route that has been least systematically countered to date. Particularly, the transmission indoors is of the highest concern but current indoor safety measures (e.g.: distancing, masks, filters) provide only limited protection. Inhalation of hypochlorous acid (HOCl) containing aerosols may become an alternate route to attack the incubating microbes in-situ and so potentially lead to a reduction of symptoms of already infected individuals. We investigated a facility-wide air-disinfection concept utilizing the potential of vaporized HOCl to become a disinfecting agent for populated indoor atmospheres. Aerosolized bacterial microbes were used as surrogates for a viral contamination, particularly the enveloped coronavirus. For the room air purification tests we aerosolized bacterial suspensions into lab chambers preloaded with vaporized HOCl solutions. Concentration of ‘free active chlorine’ in the test chamber atmosphere was determined with a special gas sensor system (Draeger AG, Lübeck, Germany) controlling the amount of vaporized HOCl via an aerosolis® device (oji Europe GmbH, Nauen, Germany). We could confirm the disinfecting power of HOCl in suspensions and determined the high efficacy of vaporized HOCl to disinfect atmospheres of populated indoor places at safe and non-irritant levels.

Keywords: Hypochlorous acid, HOCl, indoor air cleaning, infection control, microbial air burden, protective atmosphere.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 325


[1] EPA, “Disinfectant Use and Coronavirus (COVID-19) | US EPA,” 2022. (accessed Feb. 23, 2022).
[2] S. P. Ryan, “U.S. EPA. Compatibility of Material and Electronic Equipment with Hydrogen Peroxide and Chlorine Dioxide Fumigation,” Research Triangle Park, NC 27711, 2010.
[Online]. Available:
[3] E. Rasmussen, L. Robins, and J. Williams, “Inhalation of a fog of hypochlorous acid (HOCl): Biochemical, antimicrobial, and pathological assessment,” 2021, doi: 10.21203/
[4] D. Boecker, R. Breves, Z. Zhang, and C. Bulitta, “Antimicrobial Activity in the Gasphase with Hypochloric Acid,” Current Directions in Biomedical Engineering, vol. 7, no. 2, pp. 511–514, Oct. 2021, doi: 10.1515/CDBME-2021-2130.
[5] D. Boecker, R. Breves, Z. Zhang, and C. Bulitta, “Antimicrobial Activity in the Gasphase with Hypochloric Acid 4,” Biomedical Engineering / Biomedizinische Technik, vol. 66, no. s1, pp. 46–51, Sep. 2021, doi: 10.1515/BMT-2021-6009.
[6] Wang L et al., “Hypochlorous Acid as a Potential Wound Care Agent Part I. Stabilized Hypochlorous Acid: A Component of the Inorganic Armamentarium of Innate Immunity,” J Burns Wounds, vol. 6, no. e5, pp. 65–79, 2007.
[7] M. S. Yu, B. H. Kim, S. H. Kang, and D. J. Lim, “Low-concentration hypochlorous acid nasal irrigation for chronic sinonasal symptoms: a prospective randomized placebo-controlled study,” European Archives of Oto-Rhino-Laryngology, vol. 274, no. 3, pp. 1527–1533, Mar. 2017, doi: 10.1007/S00405-016-4387-5.
[8] J. F. Burd, “Ten Day Exposure to Hypochlorous Acid (Wonder Spray) Fog Results in no Detectable Effect on Blood Metabolic Panel and Minimal Lung Pathology | SciTechnol,” J Pulm Med Vol: 4 Issue: 5, 2020. (accessed Feb. 22, 2022).
[9] J. F. Burd, “Data Calculation Wonder Spray (HOCL) Kills the Bacteria that Cause Strep Throat and Pneumonia,” 2019, doi: 10.33552/OJOR.2019.02.000527.
[10] R. Gutiérrez-García, J. C. de LA CERDA-ÁNGELES, A. Cabrera-Licona, I. Delgado-Enciso, N. Mervitch-Sigal, and B. A. Paz-Michel, “Nasopharyngeal and oropharyngeal rinses with neutral electrolyzed water prevents COVID-19 in front-line health professionals: A randomized, open-label, controlled trial in a general hospital in Mexico City,” Biomed Rep, vol. 16, no. 2, pp. 1–8, Feb. 2022, doi: 10.3892/BR.2021.1494/HTML.
[11] I. Delgado Enciso et al., “Safety and efficacy of a COVID 19 treatment with nebulized and/or intravenous neutral electrolyzed saline combined with usual medical care vs. usual medical care alone: A randomized, open label, controlled trial,” Exp Ther Med, vol. 22, no. 3, pp. 1–16, Sep. 2021, doi: 10.3892/ETM.2021.10347.
[12] N. Giarratana, B. Rajan, K. Kamala, M. Mendenhall, and G. Reiner, “A sprayable Acid-Oxidizing solution containing hypochlorous acid (AOS2020) efficiently and safely inactivates SARS-Cov-2: a new potential solution for upper respiratory tract hygiene,” European Archives of Oto-Rhino-Laryngology, vol. 278, no. 8, pp. 3099–3103, Aug. 2021, doi: 10.1007/S00405-021-06644-5.
[13] H. J. Kim et al., “Effects of a Low Concentration Hypochlorous Acid Nasal Irrigation Solution on Bacteria, Fungi, and Virus,” Laryngoscope, vol. 118, no. 10, pp. 1862–1867, Oct. 2008, doi: 10.1097/MLG.0B013E31817F4D34.
[14] S.-H. Wu, J.-F. Lin, and R.-S. Jiang, “Antibacterial Effect of Hypochlorous Acid Solution on Nasal Discharge from Patients with Chronic Rhinosinusitis,” 2018, doi: 10.1155/2018/8568694.
[15] M. Sang Yu, B.-H. Kim, S.-H. Kang, and D. Jun Lim, “Low-concentration hypochlorous acid nasal irrigation for chronic sinonasal symptoms: a prospective randomized placebo-controlled study”, doi: 10.1007/s00405-016-4387-5.
[16] H. J. Cho et al., “Improved outcomes after low-concentration hypochlorous acid nasal irrigation in pediatric chronic sinusitis,” Laryngoscope, vol. 126, no. 4, pp. 791–795, Apr. 2016, doi: 10.1002/LARY.25605.
[17] B. Bale, A. Lynn, T. D.-I. Res, and undefined 2020, “Enhancement of Innate Immunity to COVID-19 with Natural Measures,”, 2020, doi: 10.35248/1745-7580.19.16.6736.
[18] J. YJ. Yu MS, Park HW, Kwon HJ, “The effect of a low concentration of hypochlorous acid on rhinovirus infection of nasal epithelial cells,” Am J Rhinol Allergy, vol. 25, no. 1, pp. 40–44, Jan. 2011, doi: 10.2500/ajra.2011.25.3545.
[19] C. Stathis et al., “Review of the use of nasal and oral antiseptics during a global pandemic,” Future Microbiology, vol. 16, no. 2. Future Medicine Ltd., pp. 119–130, Jan. 01, 2021. doi: 10.2217/fmb-2020-0286.
[20] “Esteriflu® Nasal Antiseptic.” (accessed Mar. 02, 2022).
[21] G. Zheng, G. M. Filippelli, and A. Salamova, “Increased Indoor Exposure to Commonly Used Disinfectants during the COVID-19 Pandemic,” Cite This: Environ. Sci. Technol. Lett, vol. 7, pp. 760–765, 2020, doi: 10.1021/acs.estlett.0c00587.
[22] K. Dindarloo et al., “Pattern of disinfectants use and their adverse effects on the consumers after COVID-19 outbreak,” 2020, doi: 10.1007/s40201-020-00548-y/Published.
[23] H. M. Dewey, J. M. Jones, M. R. Keating, and J. Budhathoki-Uprety, “Increased Use of Disinfectants During the COVID-19 Pandemic and Its Potential Impacts on Health and Safety,” ACS Chemical Health & Safety, vol. 29, no. 1, pp. 27–38, Jan. 2021, doi: 10.1021/ACS.CHAS.1C00026.
[24] M. Benedusi et al., “The Lesson Learned from the COVID-19 Pandemic: Can an Active Chemical Be Effective, Safe, Harmless-for-Humans and Low-Cost at a Time? Evidence on Aerosolized Hypochlorous Acid,” Int J Environ Res Public Health, vol. 19, no. 20, 2022, doi: 10.3390/ijerph192013163.
[25] N. K. Rai, A. Ashok, and B. R. Akondi, “Consequences of chemical impact of disinfectants: safe preventive measures against COVID-19,” Critical Reviews in Toxicology, vol. 50, no. 6. Taylor and Francis Ltd., pp. 513–520, Jul. 02, 2020. doi: 10.1080/10408444.2020.1790499.
[26] M. L. Casey, B. Hawley, N. Edwards, J. M. Cox-Ganser, and K. J. Cummings, “Health problems and disinfectant product exposure among staff at a large multispecialty hospital,” Am J Infect Control, vol. 45, no. 10, pp. 1133–1138, Oct. 2017, doi: 10.1016/J.AJIC.2017.04.003.
[27] O. Dumas et al., “Association of Occupational Exposure to Disinfectants with Incidence of Chronic Obstructive Pulmonary Disease Among US Female Nurses,” JAMA Netw Open, vol. 2, no. 10, pp. e1913563–e1913563, Oct. 2019, doi: 10.1001/JAMANETWORKOPEN.2019.13563.
[28] T. Weinmann et al., “Association between Occupational Exposure to Disinfectants and Asthma in Young Adults Working in Cleaning or Health Services: Results from a Cross-Sectional Analysis in Germany,” J Occup Environ Med, vol. 61, no. 9, pp. 754–759, Sep. 2019, doi: 10.1097/JOM.0000000000001655.
[29] D. Bracco, M. Dubois, R. B.-C. J. of Anesthesia, and U. 2005, “Intoxication by bleach ingestion,” Canadian Journal of Anesthesia, vol. 10, pp. 118–119, 2005, Accessed: Aug. 19, 2021.
[Online]. Available:
[30] D. Boecker, B. Breves, Z. Zhang, and B. Bulitta, “Antimicrobial Activity in the Gasphase with Hypochloric Acid 1,” Current Directions in Biomedical Engineering, vol. 7, no. 2, pp. 511–514, 2021.
[31] C. M. Spickett et al., “The reactions of hypochlorous acid, the reactive oxygen species produced by myeloperoxidase, with lipids *,” 2000.
[32] K. Nguyen et al., “The potential use of hypochlorous acid and a smart prefabricated sanitising chamber to reduce occupation-related COVID-19 exposure,” Risk Manag Healthc Policy, vol. 14, pp. 247–252, 2021, doi: 10.2147/RMHP.S284897.
[33] E. D. Rasmussen, “Stabilized Hypochlorous Acid Disinfection for Highly Vulnerable Populations Brio HOCL TM wound disinfection and area decontamination,” in IEEE Global Humanitarian Technology Conference (GHTC), 2017, pp. 1–8. doi: 10.1109/GHTC.2017.8239259.
[34] R. M. S. Thorn, G. M. Robinson, and D. M. Reynolds, “Comparative antimicrobial activities of aerosolized sodium hypochlorite, chlorine dioxide, and electrochemically activated solutions evaluated using a novel standardized assay,” Antimicrob Agents Chemother, vol. 57, no. 5, pp. 2216–2225, May 2013, doi: 10.1128/AAC.02589-12.
[35] A. T. Masterman, “Air Purification by Hypochlorous Acid Gas,” J Hyg (Lond), vol. 41, no. 1, pp. 44–64, 1941, doi: 10.1017/s0022172400012286.
[36] D. G. ff Edward and O. M. Lidwell, “Studies on air-borne virus infections: III. The killing of aerial suspensions of influenza virus by hypochlorous acid,” Epidemiol Infect, vol. 43, no. 3, pp. 196–200, 1943, doi: 10.1017/S002217240001281X.
[37] H. Hakim et al., “Evaluation of sprayed hypochlorous acid solutions for their virucidal activity against avian influenza virus through in vitro experiments,” Journal of Veterinary Medical Science, vol. 77, no. 2, pp. 211–215, Oct. 2015, doi: 10.1292/jvms.14-0413.
[38] D. Lapenna and F. Cuccurullo, “Hypochlorous Acid and its Pharmacological Antagonism: An Update Picture,” Elsevier Science Inc, 1996.
[39] A. Mohapatra and P. Wexler, “Web-Based Databases,” in Information Resources in Toxicology, 4th ed., A. M. Philip Wexler, Steve G. Gilbert, Pertti J. Hakkinen, Ed. Academic Press, 2009, pp. 619–630. doi: 10.1016/B978-0-12-373593-5.00068-9.