Ozone is an unstable molecule found in nature and it is made of three oxygen atoms. Its reaction is reversible: ozone spontaneously decomposes, and therefore it cannot be stored, but it has to be generated on site.
Ozone is produced artificially from oxygen, by using suitable Corona generators, or, alternatively, through UV radiations.
As the Ministry of Health has recognised ozone’s ability to inactivate pathogenic agents, it is strongly implied that properly carried-out ozone sanitation procedures might be able to eliminate Coronavirus.
However, ozone generated from surfaces and spaces’ sanitation procedures causes significant risks and side effects, which need to be taken into careful consideration. In fact, effective ozonisation treatments require at least between 1 and 2 ppm of ozone; such levels appear to exceed the acceptable threshold for human health.
The Italian Institute of Health has issued the following statements as part of its “Temporary Recommendations on sanitation procedures during the COVID-19 pandemic: surfaces, indoor spaces and clothing” (ISS COVID-19 number 25/2020 Report):
- “Ozone needs to be used in emptied-out and properly confined spaces
- Sanitation needs to be carried out during night hours, so that ozone levels remain within the established threshold when work resumes
- Exposure-related risks need to be carefully assessed both by sanitation operators and staff members who have access to the sanitised spaces
- Operators need to be trained and well equipped with personal protective equipment (PPE).
- Given all the above-stated, ozone cannot be destined to domestic use".
Following the sanitation procedures, excessive ozone may be rapidly eliminated by properly flowing air into the sanitised spaces and by making sure concentration levels remain below the threshold set to ensure operators’ safety.
The natural decay process, which is important to allow operators to access the sanitised spaces after treatment, varies depending on factors such as ozone’s concentration levels, environmental temperature, air humidity and the spaces’ size. At times, it might require several hours to take place.
Especially designed ozone aspirators equipped with “destroyer or catalyst systems” are used to rapidly eliminate ozone residues.
Ferrarini & Benelli has developed an effective solution, the Ozo-no! Destruction system.
Over the course of 55 years, Ferrarini & Benelli has implemented Corona treatment, a surface treatment releasing ozone into the atmosphere. In order to keep ozone concentration levels below the threshold set by law, Ferrarini & Benelli has been using the Ozo-no! Destruction system for years. Such system is currently being adopted in spaces-sanitation procedures, in order to reduce ozone’s residues as rapidly and as safely as possible.
Following the Covid-19 pandemic, many devices are not only being promoted as “disinfectant” or “sanitiser”, but also as being capable of eliminating Coronavirus. Such tools are not health-care devices and therefore, should be simply referred to as “hygienizers”.
Ozone generators need to comply with the Low Voltage Directive (Directive 2014/35/EC), the Electro Magnetic Compatibility Directive (Directive 2014/30/EC) and the RoHS – Restriction of Hazardous Substances Directive (Directive 2011/65/EC).
Sanitation guidelines (Italian Health Institute)
- Sanitating means carrying out a set of procedures and cleaning and/or disinfection operations
- Disinfecting means carrying out a treatment process to eliminate the microbial load on spaces, surfaces and materials
- Sanitisers are those products (biocides or healthcare products) officially recognised by the Ministry of Health
- Products not officially recognised by the Ministry of Health are considered as simple cleaning product (detergents)
- Treatments carried out by employing devices generating active chemical substances on the spot, like ozone and chlorine, are sanitisers, while vaporised hydrogen peroxide is an authorised sanitiser.