Decontamination Chambers and Spraying of Disinfectants in Public Spaces to minimize spread of COVID-19 virus

Decontamination Chambers

Decontamination chambers

There are many offers to donate Decontamination Chambers to hospitals and other public places, including the Ministry of Health. Many places have installed these Decontamination Chambers at their entrances/exits, making it mandatory for everyone to walk through them. These Decontamination Chambers contain various agents to spray on people including alcohol, chlorine compounds, ozonated water, soapy water and Ultra Violet (UV) radiation.

We would like to draw your attention to the views of the World Health Organization on this practice.

“We strongly advise that spraying of individuals or groups is NOT recommended under any circumstances. Spraying an individual or group with chemical disinfectants or detergents is physically and psychologically harmful and does not limit the spread of COVID-19. Even if a person is infected with the COVID-19 virus, spraying the external part of the body does not kill the virus inside the body and may worsen the clinical condition of the individual.”

For alcohol or other disinfectants to be effective, they need to be present in adequate amount for a given period of time (contact time). The nature of chambers does not sufficiently provide this. According to U.S. Food and Drug Administration (FDA) for ozone to be effective in destroying harmful bacteria, it must be present at a concentration above levels considered safe for humans.

One of the modes of transmission of COVID-19 is by contaminated hands touching the face (eyes, nose, mouth ) in addition to droplet transmission. Therefore, what needs to be done is to sanitize hands rather than try to sanitize the whole body in order to prevent transmission of this virus. Action of alcohol and other chemical disinfectants in these Decontamination Chambers is unlikely to achieve this function. Further, there is a significant fire hazard and there is wastage of alcohol and other disinfectants in large quantities when used inside these Decontamination Chambers, when they can be put to much better use in preparing hand sanitizers and for environmental disinfection in healthcare and other high risk environments.

In addition, these chemical disinfectants can have various adverse effects on humans. In particular, spraying of chlorine on individuals can lead to irritation of eyes and skin, bronchospasm due to inhalation, and potential gastrointestinal effects such as nausea and vomiting. Inhaled ozone can damage the lungs, may worsen chronic respiratory diseases like asthma and compromise the ability of the body to fight respiratory infections. Excessive exposure to UV light may put a user at risk of eye injury, skin burns or even an increased risk of skin cancer. To date, the FDA has not authorized any products using ozone gas or ultraviolet (UV) light even to clean, disinfect or sanitize inanimate objects.

Spraying disinfectants to large outdoor areas

We would like to bring attention to the practice of spraying disinfectants to large outdoor areas such as streets and public areas. The SLCM is of the view that disinfectants should be sprayed or applied only on surfaces that are highly or frequently touched by public, such as hand railings, door knobs, poles on transit vehicles, elevator buttons, park/ street benches etc. It has been proven that the virus can survive from hours to days on these contaminated surfaces. However, spraying of disinfectants in large quantities into the environment can cause environmental pollution, wastage of chemicals, harmful effects on humans as described above and harmful effects on animals and fish. Further, the action of these disinfectants on these outdoor surfaces is not yet evaluated since disinfectants may disintegrate or degrade with exposure to different environmental conditions such as sunlight. Therefore, rather than spraying large quantities of disinfectants on streets and public areas, we suggest that frequently touched surfaces should be wiped down with disinfectant solutions.

Please help prevent transmission of the COVID-19 virus by:

  1. Providing universal access to public hand hygiene stations and making their use obligatory on entering and leaving any public or private commercial buildings and any public transport facility.
  2. Improving access to hand hygiene facilities and practices in health care facilities
  3. Providing alcohol-based hand sanitizers in places where hand washing is practically not possible
  4. Promoting cough etiquette and respiratory hygiene.
  5. Routine cleaning/ wiping of frequently touched hard surfaces with detergent/disinfectant solution.
  6. Promoting social distancing even after the curfew is lifted.

Decontamination chambers and widespread spraying may give a false sense of security and members of the public may pay less attention to hand hygiene, social distancing and cough etiquette /respiratory hygiene which are of paramount importance in our fight against COVID 19.

As a professional body, SLCM advises the public to be aware of the harmful effects of the above devices and practices .

The Sri Lanka College of Microbiologists is a professional body established with the goal of promoting the advancement of Medical Microbiology in Sri Lanka and has no conflict of interest either financial or otherwise regarding content presented in this document.


Potential Risks Associated with The Use of Ozone and Ultraviolet (UV) Light Products for Cleaning CPAP Machines and Accessories: FDA Safety Communication. FDA Communication dated 27/02/2020 available at :

External Resources

Cleaning and disinfection of environmental surfaces

Author: admin

12 thoughts on “Decontamination Chambers and Spraying of Disinfectants in Public Spaces to minimize spread of COVID-19 virus

  1. up to some extent This article true but Should have told earlier .most of the local sanitizer chamber manufacturers started their production and now they are in a trouble cuz their orders getting cancelled .no one care abou it. Are the slmicrobilogy introduce equivalent or suggestion for this ???, tipical sri lanka, this artical contains politics , soon one our politician will import this chambers (from china)and all senarious will change

    1. As Medical Professionals who have experience in control of infectious diseases , we have an obligation to educate the public of the evidence based approach to the control of this pandemic .
      Political or commercial interests does not play a part in our recommendations .
      We are guided only by evidence based practices in infection control .

  2. Please check WHO, FDA websites on these topics.
    Do you see any scientific evidence for recommending this practice?
    New Zealand controlled COVID 19 without using any of these measures.
    Basic principles like social distancing, good hand hygiene, identifying infected and isolating them are the key points

    1. Please check WHO, FDA websites on these topics.
      Do you see any scientific evidence for recommending this practice?
      New Zealand controlled COVID 19 without using any of these measures.
      Basic principles like social distancing, good hand hygiene, identifying infected and isolating them are the key points

  3. Please circulate this article for the benefit of the general public and you should make the medical authorities in-charge of COVID-19 control take serious note of this.

  4. Some authority should bring these to the immediate attention of the stakeholders concerned and the general public for quick remedial action.

  5. Actually this informations are very important and useful for general public. Other thing is as mentioned in the article the people may think proper hand washing is not necessary when they expose to chamber treatment. Thank you.

  6. This is a very timely essential message . Still most of the groups of the society has not gained mode of transmission and preventive strategies of covid, including healthcare workers. Other wrong behavoiur is use of glouves by wenders , and normal socity.

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