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Speaking with Bob Long on the Benefits of Ozone

Bob Long interview on ozone generation

Bob long is our technical expert, and he recently had a conversation on the benefits and power of ozone and how best to use it.

Dispelling some of the myths surrounding ozone and explaining how and why it could be the answer to helping pubs, clubs, bars and restaurants keep their staff and customers safe.

SCROLL DOWN TO SEE VIDEO –

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Can COVID19 Be Spread When Flushing A Toilet?

An article in the National Geographic talks about the coronavirus being spread from faeces and that flushing the toilet could in fact spread the virus faster and further.

The recent study, used computer models to demonstrate that small droplets known as aerosols are made when flushing the toilet and can be sent up to 3 feet (0.91 m) into the air.

The issue is that studies regarding MERS a relative coronavirus and COVID-19, can survive in the digestive tract due to their thin membrane that protect them, unlike the noroviruses.

These droplets can remain in the air for some time allowing other people to breath in the droplets and contract the disease.

You can read the full report from the link below

https://www.nationalgeographic.com/science/article/could-flushing-public-toilet-plume-spread-coronavirus-cvd

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What type of business can benefit from an Ozone clean?

ozone sports therapy

Any business that can benefit from using ozone as part of their cleaning regime. It is fast, powerful and very effective at disinfecting and sanitising the air and surfaces.

As a gas, it gets into all the nooks and cranny’s and any residual ozone that is not used in the cleaning process reverts to oxygen and leaves no toxic residue. This makes it safe for food processing and storage areas and can be used to sanitise groceries like fresh fruit, meat and vegetables.

Due to CV19, one of the few business sectors that witnessed a surge in sales was chemical and disinfectant producers. As we know many of these products work against everything that we believe in, regarding climate change. but what really is the alternative?

A small business spending just an extra £8-£10 per week on disinfectant and other cleaning products in the next two years will spend over ONE THOUSAND POUNDS and have nothing to show for it apart of a few nice smells

Investing in a Mountain Fresh Ozone generator will ensure you maintain sterile sanitised areas which will pay for itself in as little as 3 months, and be environmentally friendly, not only will you save hundreds of £££s, but after a hard day’s work, do you really want to a deep clean or pay for a cleaner?

Why not simply flick a switch and be assured that when you arrive back at your salon/clinic shop the next morning you will  enter a Mountain Fresh  Environment.

The type of businesses already saving time and money

A few of the business that we have supplied to help them reopen safely and with  an Ozone Clean 
Airbnb apartments, Cars drivers, Barbers, Bistros, Maintenance companies, Carpet cleaners Classrooms, Coffee Shops, Cruise Ships, Day Care Centers, Dog Shelters, Dormitories, Flats Homes, Fitness centres, Gymnasiums, Golf clubs, Houses, 100s of Hairdressing Salons,  Infection Control, Kindergartens, Kitchens, Laundry Rooms, Locker Rooms remember it removes Mildew and Mould smells, Pubs, Physiotherapy clinics,  Real Estate offices, Rental Cars, Restaurants, Cleaning RV’sSchools Student Accommodation, Short term Rentals, Tobacco Odours, Taxi companies. To name but a few.

REVIEW. 24 June 2020

Thank you so much to EnVIRUSafe, by using the Mountain Fresh Ozone machine, we have been able to reopen our clinics considerably faster and provide an ongoing solution for our clients. we was a little stressed before but this has been an amazing solution for our clinics .

It honestly saves at least an hour per day of otherwise further manual cleaning.

Thanks so much, Isobel Fergusson. Elite Performance Therapy

ELITE PERFORMANCE SPECIALISTS IN THERAPEUTIC MASSAGE THERAPY AND CHIROPRACTIC CARE

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Ozone Santisation Helping to Protect Staff and Residents in Care Homes

Envirusafe helping care homes stay safeCare

Low Level Ozone Now Being Used to Help Protect Care Home Residents and Staff.

PRESS RELEASE

15-02-21

Ozone is the most powerful disinfectant known to man and is now being used in Residential Care Homes in their fight against coronavirus.

Many Care homes have been devastated by the coronavirus with many of the elderly residents and staff becoming infected.

Complex and thorough cleaning regimes have been put in place with regular deep cleans and chemical fogging being implemented to try and keep their home virus free.

While ozone has been widely used as an effective and efficient disinfectant and sanitising agent commercially to treat sewage water and prolong the life of food, for over 100 years unfortunately, very few people outside of these industries have heard of the power that ozone provides.

Ozone is one of the friendliest and cleanest ways of deactivating viruses and killing most any

pathogen and is safe to use in food processing and dining areas.

A prominent care home in Lytham St Anne’s has, like many others, been affected by COVID19 and recently discovered the benefits of ozone. In an effort to further protect their residents and staff, have installed EnVirusafe ozone sanitisers throughout the home. They have been so impressed with the Envirusafe units that they have now installed them at another home in Wales with more soon to follow in other properties in Scotland.

Bob Long, technical expert for EnVirusafe said “Companies across the UK are installing our smaller units in bathrooms, toilets, kitchens and other communal areas. It is like the silent virus assassin working in the background to destroy the virus that may be lurking in the air and on surfaces that may have been missed with regular cleaning. It provides an added layer of protection”

Bob went on to say “Most people think of the ozone layer protecting our planet but had no idea of the power it has as a disinfectant. Ozone is 50 times more potent than the strongest disinfectants used today. It is highly effective against viruses, bacteria and airborne pathogens.”

Many businesses are now discovering the power of ozone and adopting the EnVirusafe ozone sanitisation units to provide an extra layer of protection for their staff and clients.

More About Ozone

Ozone has been used commercially for many years to sanitise, sterilise and disinfect hospital operating theatres, dentist equipment, breweries, food processing plants and sewage water. It has also been used successfully for certain medical ailments like hard to treat fungal and bacterial infections as well as medially to treat Covid patients, (although without the approval of the FDA).

Ozone is a gas molecule made up of 3 oxygen atoms with amazing disinfectant properties. It destroys the coronavirus by oxidisation, breaking down the outer protein shell of the virus, preventing it from replicating or attaching itself to host cells.

Unlike some chemicals there is no toxic residue after using ozone. Ozone that is not used in the sanitisation process reverts back to oxygen over time or if speed is required carbon can be used neutralise any remaining ozone.

Ozone treatment has also shown to be effective in sanitising PPE including N95 masks, goggles and shields without damaging the integrity of the equipment. (ref 1)

Ozone has been proven to destroy many viruses including the SARS (ref 2)

Like all strong disinfectants, liquids and gases, ozone needs to be treated with care and safety procedures should always be followed. While low dose units produce ozone that does not exceed recommended safety levels, prolonged exposure to high levels of ozone can be detrimental to health, but it is generally considered safer than chlorine and other chemicals and easier to use than chemical fogging.

Ozone treatment is not a replacement for a good cleaning regime but used as an added layer of protection.

As a gas, it not only is affective in sanitising the air, but it can also sanitise inaccessible and hard to reach surfaces and anything else it touches.

For more information contact
Bob Long (Head of Technical) – 07793 274 189 bob@envirusafe.co.uk
Lloyd Hester ( Operations Manager) 07557 552 484 lloyd@envirusafe.co.uk

EnVirusafeenvirusafe.com
info@envirusafe.co.uk
General phone 01925 321 888

Download a printed PDF copy

Reference material –

(1) Ozone used to disinfect PPE https://news.gatech.edu/2020/07/09/ozone-disinfection-could-safely-allow-reuse- personal-protective-equipment

(2) Ozone and Covid-19 https://www.researchgate.net/publication/347563669_COVID-19_and_Ozone

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Safe and Effective Use of Ozone as Air and Surface Disinfectant in the Conjuncture of Covid-19

Technical Note

Elena Grignani 1, Antonella Mansi 2, Renato Cabella 2, Paola Castellano 2, Angelo Tirabasso 2, Renata Sisto 2, Mariangela Spagnoli 2, Giovanni Fabrizi 2, Francesco Frigerio 1
and Giovanna Tranfo 2,*

ICS Maugeri Spa SB, Environmental Research Centre, Via Atene, 9, 35010 Perarolo di Vigonza (PD), Italy; elena.grignani@icsmaugeri.it (E.G.); francesco.frigerio@icsmaugeri.it (F.F.)
INAIL (Italian Workers’ Compensation Authority), Department of Occupational and Environmental Medicine, Epidemiology and Hygiene, Via di Fontana Candida, 1, 00078 Monte Porzio Catone (RM), Italy; a.mansi@inail.it (A.M.); r.cabella@inail.it (R.C.); p.castellano@inail.it (P.C.); a.tirabasso@inail.it (A.T.); r.sisto@inail.it (R.S.); m.spagnoli@inail.it (M.S.); g.fabrizi@inail.it (G.F.)

Abstract: The present paper extrapolates quantitative data for ozone virucidal activity on the basis of the available scientific literature data for a safe and effective use of ozone in the appropriate cases and to explore the safety measures developed under the stimulus of the current emergency situation. Ozone is a powerful oxidant reacting with organic molecules, and therefore has bactericidal, virucidal, and fungicidal actions. At the same time, it is a toxic substance, having adverse effects on health and safety. Its use is being proposed for the disinfection of workplaces’ and public places’ atmosphere, and for disposable masks and personal protective equipment disinfection for reuse, with particular reference to the COVID-19 pandemic outbreak. Ozone can be generated in situ by means of small, compact ozone generators, using dried ambient air as a precursor. It should be injected into the room that is to be disinfected until the desired ozone concentration is reached; after the time needed for the disinfection, its concentrations must be reduced to the levels required for the workers’ safety. The optimal use of ozone is for air and surface disinfection without human presence, using a concentration that is effective for the destruction of viruses, but not high enough to deteriorate materials.

Keywords: SARS-CoV-2; ozone generators; sanification; disinfection; virucidal efficacy; occupational exposure; personal protective equipment

1. Introduction

The Report ISS Covid-19 n. 25/2020 [1] issued on May 2020 by the Italian Institute of Health (ISS), reports recommendations on the sanification of non-healthcare settings during the COVID-19 emergency. In this document, the term “sanification” is intended as the process of cleaning and/or disinfecting and maintaining good air quality, taking into account scientific evidence of COVID-19 virus persistence on different surfaces, and the efficacy of cleaning and disinfection products for indoor environments. Ozone is evaluated, among other disinfectants, on the basis of the available literature and of the statements of internationally recognized organizations. European Chemical Agency (ECHA), Centers for Disease Control and Prevention (CDC), Food and Drug Administration (FDA), United States—Environmental Protection Agency (US-EPA) and the International Ozone Association (www.iao-pag.org) confirm the effectiveness of ozone for the inactivation of many viruses, although without being aware of specific research on SARS-CoV-2.

Ozone, an allotropic form of oxygen, is an inorganic gas (CAS n. 10028-15-6) constituted by three oxygen atoms (O3) arranged in a bent structure, where the distance among oxygen atoms is 1.26 Å. It easily decomposes into oxygen (O2) and one single, very reactive oxygen atom. Ozone is present in nature and its concentration in the atmosphere is approximately 0.04 parts per million (ppm: 1 ppm

~ 2 mg/m3). It is also produced by ultraviolet irradiation of oxygen or other precursors such as volatile organic compounds and nitrogen oxides present in the atmosphere. About 90% of the atmospheric ozone is located in the stratosphere, and therefore called stratospheric ozone. The solubility of ozone in water is 49.0 mL/100 mL (at 0 ◦C), tenfold than oxygen, thus causing an immediate reaction with any biomolecule in biological fluids. Its density (2.14 kg/m3) is higher than that of air, letting it concentrate close to the ground in indoor environments.

Ozone is well known for its protective role in the earth’s ecological environment. Being a powerful oxidant, it is able to react with organic molecules containing double or triple bonds. This is the origin of its bactericidal, virucidal, and fungicidal actions, which are used in water treatment, odor control and medicinal applications [2].

The inhibitory and lethal effects of ozone on pathogenic microorganisms have been observed since the 19th century, and the most cited explanation of these effects is based on the disruption of their envelopes through peroxidation of phospholipids and interaction with proteins [3]

The ozone virucidal effect has been also studied by Roy et al. in 1981 [4], showing that after 30 s of exposure, 99% of the viruses were inactivated: their envelope proteins had been damaged, causing possible failure of attachment to normal cells, and their single-stranded RNA was broken.

Viruses are small particles built of macromolecules; unlike bacteria, they need a host cell to multiply, and being unable to repair oxidative damage, they are more susceptible to oxidative action than prokaryotic or eukaryotic organisms [5].

Ozone interacts with viruses in which a lipoprotein envelope is present, by spreading through the protein coat into the nucleic acid core, damaging their DNA or RNA [6–8]. Most studies on ozone’s virucidal effects have focused on ozone’s ability to break apart lipid molecules with multiple bonds. In fact, if the envelope of the virus is fragmented, its DNA or RNA core cannot survive. The enveloped viruses are usually more sensitive to physical–chemical challenges than naked ones.

Naked viruses only have a nucleocapsid, which is a protein capsid that covers the nucleic acid core (DNA or RNA). Even if ozone’s effect on unsaturated lipids is one of its best-documented biochemical actions, it can interact with proteins, carbohydrates, and nucleic acids [7]. Due to its high reactivity, the toxic effects of ozone reaction products should also be considered.

Manufacturers and sellers of ozone devices use a variety of terms that suggest that ozone is a “healthy” kind of oxygen, but ozone is a toxic gas with very different properties from oxygen, and concentrations that are safe to breathe are unlikely to be effective in controlling indoor air pollution [8].

A comprehensive evaluation of ozone human health effects was recently performed by the US EPA, as part of the “Integrated Science Assessment for Ozone and Related Photochemical Oxidants” [9]. According to this report, recent studies support and expand upon the strong body of evidence that short-term ozone exposure causes respiratory effects. The strongest evidence comes from controlled human exposure studies demonstrating ozone-induced decreases in lung function and inflammation in healthy, exercising adults at concentrations as low as 60 ppb after 6.6 h of exposure. In addition, epidemiologic studies continue to provide strong evidence that ozone is associated with respiratory effects, including asthma and chronic obstructive pulmonary disease exacerbations. The available evidence was inadequate to determine whether there was a causal relationship between exposure to ambient ozone and cancer.

Currently, in Italy, ozone can be used exclusively as a sanitizer. It is presently being reviewed by the European Environmental Agency and/or Switzerland for use as a biocide, in disinfection, food and animal’s feeds, drinking water, and as a preservative for liquid systems, under the Biocidal Products Regulation (BPR) of ECHA.

Gases 2021, 1 21

The objective of this study was to conduct a literature review on the ozone virucidal efficacy in order to individuate the optimal conditions (concentration, contact time, microclimate) for its possible use as disinfectant for indoor environments and Personal Protective Equipment (PPE), with particular reference to SARS-CoV-2. In addition to this, some critical aspects that currently prevent the use of this gas as a disinfectant, including safety risks and the lack of Indicative Occupational Exposure Limit Values (IOELVs) at European Union level, were further explored.

2. Methods

2.1. Literature Search

A literature review, started on June and ended November 2020, was carried out using PubMed, Scopus and Google Scholar databases. A first search was conducted to identify publications dealing with the ozone virucidal activity under different experimental conditions, as gas concentration, contact time and microclimatic parameters. Articles were identified using the following keyword combinations: (“ozone” OR “ozone generator” OR “gaseous ozone”) AND (“disinfectant” OR “disinfection” OR

“sanitation” OR “efficacy” OR “treatment” OR “activity”) AND (“coronavirus” OR “COVID-19” OR “SARS-CoV-2” OR “SARS-CoV-1” OR “viruses”).

In the same databases, another search was performed in order to find articles regarding the use of ozone as a disinfectant for the safe reuse of PPE and the possible damage caused to materials. For this purpose, the following search string was used: (“PPE” OR “Personal Protective Equipment” OR “N95 Mask” OR “KN95 Mask” OR “Filtering Face Piece” OR “FFP” OR “gowns” OR “gloves” OR “glasses” OR “shields” OR “goggles”) OR (“rubber” OR “polyethylene” OR “polypropylene” OR

“cotton fabric”).
Publications titles and abstracts were reviewed and only those that met the criteria described

above were eligible for the inclusion. Documents on the use of ozone in aqueous solution or those about ozone therapy for patients were not taken in consideration. Only articles written in English were included.

2.2. Metrics for Airborne Microorganisms Inactivation

By examining the scientific literature about ozone virucidal efficiency, the ozone concentration values that were able to inactivate viral microorganisms at normal ambient temperature and relative humidity, in a certain exposure time, were extracted.

Normalized infectious ratios (NIRs) were calculated by dividing the mean sample plaque-forming unit (PFU)/mL by the mean control PFU/ml and the mean control genomes/ml by mean sample genomes/ml. Results were multiplied together. NIRs were calculated both for ozone and for the reference (air) conditions.

Lastly, relative infectious ratios (RIRs) were obtained by dividing each ozone-NIR with the corresponding median air-NIR.

RIR = NIR O3/median [NIR air] (1) The RIRs represent the effect of ozone only, since data were corrected for the effect of relative

humidity (RH) and aerosol aging without ozone [10].

3. Results

3.1. Ozone Virucidal Efficacy

A total of 109 documents were retrieved in databases using all the above-mentioned keywords and search strings, but only 17 papers were eligible for inclusion. The review of the existing scientific literature demonstrates that ozone is an extremely rapid and potent virucidal; however, exact gaseous

Gases 2021, 1 22

ozone dosages are limited to only a few studies, as virucidal action of ozone happens in seconds or fractions of seconds and this makes the measurement of viral inactivation technically challenging [3]. The data available in the literature do not cover all virus types. In some studies, the virucidal activity of ozone was tested on pathogenic viruses of particular clinical interest such as Poliovirus,

Norovirus, Herpes Simplex Virus and Influenza virus [4–6,10]; in others, instead, the bacteriophages were used in place of airborne human pathogenic viruses [8].

Hudson [5] developed a prototype ozone generator (Viroforce 1000) that contains eight corona discharge units, and that subsequently removes ozone by a built-in catalytic converter. In this study, the maximum anti-viral efficacy was obtained at a concentration of 25 ppm of ozone for 15 min, followed by a short period of >90% relative humidity. All the 12 viruses tested were inactivated by at least three orders of magnitude, both in laboratory and in simulated field trials, on different hard and porous surfaces, and in the presence of biological fluids. Viral activity was tested through cellular culture.

Inactivation of herpes simplex virus (HSV) by ozone was studied by Petry et al. [7], generating ozone by a commercial air purifier (Brizzamar, Ronda Alta, RS, Brazil). The ozone concentration in the environment was monitored through the EcoSensor Model OS-4 (Ozone Switch TM, Newark, CA, USA). With an ozone exposure of 1–3 h at concentrations between 0.02 and 0.05 ppm, a 68–90% reduction in viral activity tested through cellular culture was obtained.

Dennis [11] tested five commercial ozone generators used to reach the target ozone concentration in a box for DPI regeneration. The antiviral efficacy was guaranteed at 10–20 ppm for 10 min, based on the results of other papers.

Tseng and Chihshan [12] studied the inactivation of four different viruses, representative of ssDNA, ssRNA, dsDNA, and enveloped dsRNA categories, using an ozone generator with pure oxygen at 3 L/min (OZ1PCS-V/SW, Ozotech Inc., Yreka, CA, USA). Airborne Ozone concentrations were measured by an ozone analyzer (model 401, Advanced Pollution Instruments, San Diego, CA, USA), with a detection limit of 1.0 ppb. Ozone levels of 0.6–1.2 ppm for 20–112 min time guaranteed 90% and 99% of inactivation, respectively. For all the tested viruses, the ozone concentration required for the same inactivation level was lower at 85% RH than at 55%.

Zhang et al. [13] demonstrated that ozone in aqueous solution is able to inactivate SARS-CoV-1, the etiologic agent responsible for the Severe Acute Respiratory Syndrome (SARS) spread in 2003, which has a very similar structure to the SARS-CoV-2 virus, causing the current COVID-19 pandemic. Afterwards, Hudson et al. [5] tested the virucidal action of ozone on murine coronavirus (MCV), a species of coronavirus which infects mice, commonly used as a surrogate for SARS-CoV-1.

As SARS-CoV-2 is an enveloped virus, particularly sensitive to oxidant action, the scientific evidence suggested that ozone would effectively inactivate this new coronavirus too.

Moreover, some studies [8,12,14] showed that the important factor for inactivation of viruses and other microorganisms is the total ozone dose, which can be calculated as the product of exposure time and concentration. In fact, low concentrations of ozone for longer exposure times produce the same results as shorter exposures at high concentrations.

Dubuis ME et al. [10] tested the efficacy of ozone and RH combinations for the inactivation of different airborne viruses. Four phages (φX174, PR772, MS2 and φ6) and one eukaryotic virus (murine norovirus MNV-1) were exposed to low ozone concentrations (1.23 ppm for phages and 0.23 ppm for MNV-1) at different levels of RH, for time intervals ranging from 10 to 70 min. A two orders of magnitude inactivation was achieved for φX174, MS2 and MNV-1 with an ozone exposure of 40 min at 85% RH. For PR772 and φ6, exposure to the reference condition at 20% RH for 10 min gave the same results. In according to previous studies [15], these results suggest that ozone, even when used at a low concentration, is a powerful disinfectant for airborne viruses and other microorganisms if combined with a high RH level. It is well known that ozone is an oxidizing agent in aqueous solutions, and when in the gas phase, reacting with water, it generates free radicals that increase its disinfection power.

Gases 2021, 1 23

Tseng and Li [8] also observed that the phages inactivation increased when high 85%RH was used and further studies demonstrated that ozone under high RH conditions leads to the formation of more free radicals than in dry air [14,16].

In another study, Blanchard et al. [17] showed that a concentration of 20 ppm of ozone is able to inactivate some enveloped respiratory viruses (influenza A virus and respiratory syncytial virus) that are very similar in form and function to SARS-CoV-2. The authors performed a series of experiments under different relative humidity conditions, demonstrating that, at 50–70% RH, the ozone treatment was highly effective (99.99% reduction in viral infectivity) because of a greater production of highly reactive hydroxyl radicals. Therefore, they conclude that the humidity is an important parameter to evaluate, because, under rather dry environmental conditions, the disinfection procedure could require considerably longer exposure times.

More recently, Yano et al. [18] reported the first results about the inactivation of SARS-CoV-2 using ozone. In this study, the viral load of SARS-CoV-2 (JPN/TY/WK-521 strain) was determined by using the plaque assay on confluent layers of VeroE6/TMPRSS2 cells in culture plates. Cell monolayers were allowed to dry before exposure to ozone at concentrations of 1.0 and 6.0 ppm, for 60 and 55 min, respectively. Viral infection assays were performed at room temperature (25 ◦C) and 60–80% RH and the results expressed in PFU/mL. At 6.0 ppm of ozone for 55 min, results showed a significant reduction in the number of plaques (1.0 × 103 PFU/mL) compared to control (2.0 × 106 PFU/mL). Therefore, authors suggest that it is plausible to believe that at slightly higher concentrations and for shorter periods, this gas can be used in particularly critical environments (healthcare setting, hospices, etc.) where a rapid and effective disinfection is required. Table 1 shows the results of ozone virucidal efficacy on some pathogenic viruses including SARS-CoV-2.

3.2. Total Ozone Dose

From the results of these studies, we can extrapolate a relationship between the ozone concentration used and the contact time needed for a viral inactivation >90% (Figure 1).

Gases 2021, 1
Gases 2020, 1, FOR PEER REVIEW

y = − 24.18 ln (x) + 77.10

(2)

y = − 24.18 ln (x) + 77.10
where x is the ozone concentration expressed in ppm, with a good correlation (R2 = 0.73, p = 0.0015).

(2) where is the ozone concentration expressed in ppm, with a good correlation (R =0.73,p=0.0015).

The last point of the curve (25 ppm) derives from the experiment of Hudson [52], where contact time was not determined by inactivation but set a priori, and therefore it does not fit into the curve.

However, contact times below 1 min are not technically advisable.

time was not determined by inactivation but set a priori, and therefore it does not fit into the curve.

The choice of a higher concentration and a shorter time or vice versa should be based on the application and specific issues of the location to be disinfected..

However, contact times below 1 min are not technically advisable.

The measurement of the ozone concentration is based on the spectrophotometric technique of

the absorption, by the ozone molecules, of ultraviolet radiation with a wavelength equal to 254 nm.

There are also ozone meters with electrochemical detection principle, both fixed and portable, with extremely affordable costs.

3.3. Ozone Production


Due to its high reactivity, ozone cannot be stored, but it is usually generated in situ.

3.3. Ozone Production

oxygen or water by means of different energy sources. The methods normally used to produce ozone are:

Due to its high reactivity, ozone cannot be stored, but it is usually generated in situ.

– Photochemical method (air, oxygen);

The methods normally used to produce ozone are:

– Dielectric barrier discharge (air, oxygen).

– Electrolysis of water (water);

Electrolysis of water is the preferred technology for ozone water production and, as such, it is

– Photochemical method (air, oxygen);

not useful for air disinfection.

– Dielectric barrier discharge (air, oxygen).

Ultraviolet irradiation of oxygen and nitrogen oxides is the main source of natural ozone, but it is not very practical when high quantities are needed. The ozone production efficiency increases,

Electrolysis of water is the preferred technology for ozone water production and, as such, it is not decreasing the wavelength, with a peak efficiency at 185 nm [19], well below the 254 nm wavelength useful for air disinfection.

used by germicidal lamps.

Ultraviolet irradiation of oxygen and nitrogen oxides is the main source of natural ozone, but it is not very practical when high quantities are needed. The ozone production efficiency increases, decreasing the wavelength, with a peak efficiency at 185 nm [19], well below the 254 nm wavelength used by germicidal lamps.

Inactivation time (min)

Gases 2021, 1 25

Therefore, consumer-oriented UV-ozone “air purifiers” produce, if any, an amount of ozone just above the 0.04 ppm olfactory threshold. However, for applications not requiring high concentrations, as for laboratory standards, UV lamps are an option.

When high yields are required, ozone is generated via the dielectric barrier discharge (DBD), also known as the corona effect. The name derives from the shape of the region of glowing gas formed around an electrode when the electric field strength is high enough for gas ionization, without forming an arc. The feeding gas can be pure oxygen or air, and since the ozone yield is reduced by air humidity, a compressor with the purpose of drying air shall be installed at the inlet. This is one of the most effective technologies for ozone production, and therefore most of the commercial generators are based on DBD.

Ozone production is generally affected by several parameters like the nature of the electrode, the reactor geometry and configuration, the power source used, the gas source and flow rate in reactor, and physical variables like pressure, humidity and temperature. Only DBD generators fed with environmental air will be addressed here. The air that feeds the generator must be purified from possible contaminants like particulate matter, VOC, etc., in order to avoid the generation of reaction by-products that are harmful to human health.

Ozone generators specifications usually provide a production of ozone amount expressed in mg/hour.

The volume of the space to be disinfected should be measured and expressed in cubic meters (m3).

The amount of ozone produced in 1 h, divided by the volume of the room, will provide the concentration of ozone that can be reached in 1 h, or in 1 min if it is divided by 60.

For example, a small commercial ozone generator can produce 2000 mg/hour. For a room of 10 × 10 × 3 m (300 m3) the ozone concentration of 6.6 mg/m3 can be reached after 1 h, which can be converted to 3.36 parts per million (ppm) as follows

ppm = mg/m3 × 24.45/48 (3)

where 24.45 is the volume of 1 mole of an ideal gas at 1 atm and 25◦ C and 48 g/mol the molecular weight of ozone.

Some papers use the product of ozone concentrations for the exposure time in order to compare the efficacy of different conditions, so the unit becomes min.ppm or min.mg/m3.

The actual ozone yield strongly depends on environmental parameters such as humidity [20], with decreased efficiency at a higher humidity. When the generator is stopped, the interaction of the ozone molecules with the environment, and even among one another, leads to the recombination of ozone into oxygen [21] within a time depending on air flow, temperature and humidity.

Low-cost generators, designed to be manually started and stopped, do not allow for achieving a reliable concentration and holding it for a definite time, if other technical measures are not set up.

3.4. Disposable Masks and Personal Protective Equipment Disinfection for Reuse

A total of 55 documents were retrieved using the mentioned keywords in bibliographic databases, but only 20 were selected for this study.

In times of emergency, disinfection and sterilization protocols, even for disposable PPE (gloves, glasses, face shields, gowns, filtering facepieces respirators), may be needed. A summary of the possible issues for each piece of equipment is reported here.

It is important to keep in mind that reuse should be regulated by a good practice procedure in order to guarantee:

  • –  That disinfection for reuse should not be applied to PPE that are exhausted for another specific use (for example protection from dusts or fibers);
  • –  That an individual PPE would be reused only by the same individual;
  • –  That the acceptable number of reuses has been determined and has not been reached.

Gases 2021, 1 26

Most non-reusable PPEs are made of polymeric materials, which are, by nature, among the cheapest and easiest to work. Ozone contributes strongly to the aging of rubber through the splitting of alkenic double bonds, according to the ozonolysis mechanism described for the first time by Criegge [22]. Ozone, therefore, has a high affinity with unsaturated polymers. To test the resistance of rubber to ozone exposure there are several technical standards, in which the applied ozone concentrations are in the order of a few ppm [23–26].

Jaffe reports that the rate of oxidation at ordinary temperatures is very low, but, depending on the type of rubber compound, the rate increases significantly with each rise of about 10 ◦C [27]. The same author also states that the main factors influencing the action of ozone on rubber are the stress degree, the nature of the rubber compound, the ozone concentration, the exposure period, the speed of contact with the surface and the temperature. The simultaneous action of stress and ozone is a necessary condition for the manifestation of visible cracks [28]. It is also known as the combined effect between ozone and other agents, such as UV [29,30] or chemicals [31], causes a greater and faster oxidation than that obtained from ozone alone.

In conclusion, materials such as natural rubber (latex) and nitrile are the least resistant to ozone. Natural rubber or some synthetic rubbers show cracks if they are just 2–3% stretched and simultaneously exposed to an atmosphere containing 0.01–0.02 ppm of ozone [32]. Instead, butyl rubbers, neopreneandpolyurethane, exposed to the same ozone concentrations, withstand almost triple the amount of stress compared to natural rubbers. Finally, rubbers such as silicone, polyacrylic, chlorosulfonated polyethylene, and ethylene–propylene copolymer, characterized by saturated chemical structures, are the most resistant [27].

Gloves are among the most common and cheapest protective devices. The disposable gloves used in healthcare settings are normally made of nitrile or latex. Considering that the reuse of disposable gloves is rather difficult, it is not considered particularly useful to further investigate any sterilization procedure, even with agents different from ozone.

Potentially infected droplets of liquid and splashes directed towards the eyes can be stopped by goggles or safety glasses or by a shield covering the face down to the chin. Because of its excellent optical and mechanical properties, these PPE are normally composed of polycarbonate, which offers excellent resistance to ozone. Therefore, the use of ozone sterilization procedures could adapt very well to this type of PPE.

Disposable filtering facepieces respirators (FFR) are designed to reduce the inhalation of particulate contaminants (such as droplets or aerosols). The filtering action is carried out by the non-woven fabric, usually polyethylene and/or polypropylene, of which the FFR is made. These materials are normally resistant to the chemical action of ozone. Regarding the sterilization of FFR, Zhang et al. [13] studied the inactivation of SARS-CoV-1 by using different concentrations of ozone and discovered that this virus can be inactivated using a concentration of ozone equal to 27.73 mg/L for 4 min. A recent study [33] showed that exposure to ozone concentrations of 400 ppm for up to 10 cycles of two hours (at room temperature and RH 75–90%) did not degrade the filtration and fit capabilities of the FFR but caused an unclear residual odor that needs further, more detailed, investigation. In another study [11], authors exposed the non-woven polypropylene material used for the N95 FFR at ozone concentrations of 10 and 20 ppm, for a duration of 10, 20 and 60 min. They observed the absence of microscopically visible damage to the fibers; in addition, they performed tests according to the NIOSH standard and also demonstrated the absence of loss of filtration efficiency.

A critical aspect could relate to the retention straps and therefore to the fitting: in fact, in some FFR models, straps can be made of latex and they could lose tensile strength or even break.

In any case, the fact that ozone is a gaseous virucidal makes it a particularly effective method for reaching shadows and crevices and sterilize porous and fibrous materials better than other methods (for example, UV).

Medical gowns can be made of different materials, on which their reusability depends. The reusable gowns are made of cellulose fabrics (like cotton) while the disposable gowns are generally made

Gases 2021, 1 27

of artificial rubber (propylene or polypropylene). The elective disinfection treatment for cotton gowns includes hot water, soap and disinfectants like chlorine [34]. On the other hand, the use of low ozone concentrations (0.02–0.06 ppm) on cotton fibers can increase fluidity and decrease breaking strength [35] as well as a progressive whitening of dyed fabrics [36,37]. The reactions between ozone and dirty, used clothes can lead to the production of harmful volatile organic compounds like aldehydes and acetone [38].

Ozone does not seem to have particular contraindications for sterilizing propylene or polypropylene gowns (like Tyvek©), and it is able to easily reach the internal parts of the folds of the fabric.

3.5. Ozone Negative Impact on Consumer Goods and Other Materials

Ozone, being a strong oxidizing agent, can damage materials such as rubber, plastics, fabrics, paint and metals. Exposure to airborne ozone can progressively damage both the functional and aesthetic qualities of materials and products, shortening their life. This inconvenience can cause significant economic losses for industries and other activities, because of the increased costs of maintenance or of the replacement of the damaged goods [39].

Limited data are available, but they indicate significant damage to rubber products and surface coatings, while textiles and other polymeric materials seem not to be affected in the range of atmospheric concentrations [40]. Ozone is also able to fade dyes on nylon and acetate, and most of the natural dyes and dye-based pigments used by artists. It also plays a role in the process of the corrosion of metals like copper and aluminum [31].

3.6. Occupational Exposure Limits

The U.S.A. Occupational Safety and Health Administration (OSHA) has set Public Health Air Standards of 0.1 ppm for 8 h or 0.3 ppm for 15 min as the limit of the amount of ozone to which people can be safely exposed.

The Directive 2008/50/EC of the European Parliament and of the Council of 21 May 2008, on ambient air quality and cleaner air for Europe, transposed in Italy as Legislative Decree 155/2010, sets two ozone concentration thresholds: an information threshold of 180 μg/m3 per hour, and a long-term objective for the protection of human health of 120 μg/m3 (0.24 ppm), calculated as the daily maximum of the moving average of 8 h.

The olfactory perception threshold of ozone is 0.04 mg/m3, equal to ~ 0.02 ppm, concentrations that have no effect on human health.

A guidance on the safe use of ozone provided by manufacturers and importers of ozone generators is available on the ECHA website [41].

For ozone, no Indicative Occupational Exposure Limit Values (IOELVS) have been set at European Union level, but some Member States have established national occupational exposure limit values, both for long- and for short-term exposures.

In the Italian legislation (attachment XXXVIII of Legislative Decree 81/08) there are no limit values for the occupational exposure to ozone.

Limit values in use in several countries can be found on the German IFA-GESTIS database [42]. Alternatively, the values indicated by the American Conference of Governmental Industrial Hygienist (ACGIH) [43] can be taken into account, which also are related to the physical activity carried out by the workers. Two European countries, Ireland and Spain, have adopted the same ACGIH limit values.

Occupational Exposure Limit Values in different European and extra European countries are reported in Table 2 [44]. Values are very consistent and go from a minimum of 0.05 ppm for long-term to a maximum of 0.3 ppm for short-term exposures.

3.7. Safety Issues

Ozone generators are currently being promoted as effective tools for removing pollution and odours from indoor air, but it must be remembered that ozone is associated not only with adverse health effects but also with safety issues.

Ozone generators are high voltage electric machines, with all the safety implications involved.

Moreover, the corona effect, whichever the frequency of the applied current, produce a broad spectrum of radio frequencies depending on many different parameters [45].

The ECHA safety guidance forbids the entire room where the ozone generator is deployed to pacemaker bearers. The actual extension of the area where the electromagnetic field exceeds the reference levels set for the protection of general public and workers should be addressed in the risk assessment. Depending on the configuration of the generator, this area could range from centimeters to meters; however, a too high radio frequency emission could impair the correct functioning of other devices, including medical equipment.

4. Discussion

Ozone, being a gas, is very effective in reaching all the points in the space and on the surfaces, performing a rapid and extensive disinfection of the environment simply by exploiting its natural air dispersion. The UV-C radiation has effective antimicrobial properties but is well known that there are shady areas where the disinfection could not occur. Liquid disinfectants can be sprinkled as natural air diffusion is limited.

Nevertheless, to date, few studies are available on ozone virucidal activity and these were carried out using very different experimental conditions on some pathogenic viruses or their surrogates. Since standardised methods for the assessment of ozone virucidal efficacy are not available, the heterogeneity of experimental procedures performed makes it difficult to compare the results. In the studies examined, the experiments were carried out using various ozone generators, under different conditions of temperature and relative humidity, on different viruses. By extrapolating data on ozone virucidal activity at room temperature and medium relative humidity between 35 and 55%, we found that an opportune combination of ozone concentration, in the range 1–25 ppm, and contact times between 10 min and 3 h are able to efficiently inactivate (>90%) some pathogenic viruses or their surrogates. A mathematical relationship between ozone concentration and the needed contact time is reported.

In these studies, some authors showed that a parameter that plays an important role is the relative humidity that increases ozone virucidal activity. Among these, very recently, Yano et al. [22] reported the first in vitro inactivation study on SARS-CoV-2 virus by 6.0 ppm ozone at room temperature and 60–80% RH, obtaining, in only 55 min, a 99.9% reduction (which equates to about 3-Log) in the number of the PFU/mL

Overall, findings suggest that ozone used at a low concentration is a powerful disinfectant (up to 99% reduction) when combined with a high RH because, when air humidity is higher, more free radicals will be formed, which are able to kill airborne viruses.

There is no harmonized classification of ozone. According to the classification provided by companies to ECHA, ozone should be classified for acute inhalation toxicity (Acute Tox. 1), skin corrosion (Skin Corr. 1B), serious eye damage (Eye Damage 1) and specific target organ (airways) repeated toxicity (STOT Rep. Exp. 1). As reported by the ECHA Registry of classification and labelling (CLH) Intentions, a proposal to classify ozone also for mutagenicity (Muta. 2) and carcinogenicity (Carc. 2) was submitted by Germany in 2016.

Due to its toxicological properties and its capability to degrade several materials, the optimal use of ozone for the disinfection of air and surfaces is in the absence of humans, using a dose and time of usage sufficient to destroy viruses, but having minimal degradation effects on materials.

Gases 2021, 1 30

If it is not possible to demonstrate that, after the disinfection of a workplace, airborne ozone concentrations guaranteeing the safety of the workers have been reached, it is necessary to determine said concentrations with an appropriate method.

The use of ozone as a disinfectant for the re-use of PPE has been further investigated in the light of COVID-19 pandemic as possible solution to the shortage of personal protective equipment. On the basis of the available information, the use of ozone disinfection procedures could adapt very well to goggles, safety glasses and face shields, propylene or polypropylene gowns, while for disposable filtering facepieces’ respirators, further detailed investigations are needed.

The Italian Institute for Public Health (ISS) [44] concludes that this gas must be used in unoccupied and confined environments, and that it is necessary to evaluate the risk of exposure of both operators (who must be trained and equipped with suitable personal protective equipment) and of the staff who will use the disinfected premises.

5. Conclusions

The examination of the literature on ozone virucidal activity showed that ozone, used at a low concentration, is a powerful agent (up to 99% reduction) when combined with a high RH, for the disinfection of air, surfaces and some personal protection devices. The optimal minimal dose and the needed contact time can be calculated in order to sufficiently to destroy viruses, but this combination should be tested for possible degradation effects on materials and goods.

The major drawbacks for the use of ozone as a disinfectant are the risks that it poses to human health and safety: it is able to induce decreases in lung function and inflammation, and is associated with respiratory effects, including asthma and chronic obstructive pulmonary disease exacerbations. Moreover, ozone generators are high-voltage electric machines, with all the safety implications involved. If other, less harmful, disinfectants are not applicable, ozone is a valid option, provided that people/workers are never present during the treatment.

Author Contributions: Conceptualization, E.G., G.T., R.S. and F.F.; investigation, E.G., G.T., A.M., R.C., P.C., A.T., R.S., M.S., G.F., F.F. and G.T.; data curation, G.T. and R.S.; writing—original draft preparation, E.G., G.T., A.M., R.C., P.C., A.T., R.S., M.S., G.F., F.F. and G.T.; writing—review and editing, E.G. and G.T. All authors have read and agreed to the published version of the manuscript.

Funding: This research received no external funding.
Conflicts of Interest: The authors declare no conflict of interest.

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How are you most likely to catch Covid?

New research says the risk of surface transmission is low

Luke MintzFri, 12 February 2021, 10:46 am·7-min read

Covid droplets
Covid droplets

What is the most likely way you will catch coronavirus? Is it through cough droplets, transferred at close range; or tiny particles, known as aerosols, that linger in the air for hours; or is it through touching an infected object?

It seems a simple enough question, and perhaps one that should already have been answered 11 months into a pandemic that at the time of writing has killed 2.4 million people (including 115,000 in the UK). But virology – the study of viruses and how they spread – is a famously tricky science.

The problem, says Paul Hunter, a professor of medicine at the university of East Anglia, and occasional advisor to the World Health Organisation (WHO), is that it is very difficult for scientists to isolate how exactly a patient has picked up a virus – especially once it is as widespread as Sars-Cov-2 (the virus that causes Covid-19), which has now infected 107 million people across the world.

An infected person might indeed have touched the same supermarket checkout screen as another who recently tested positive – but they also went shopping, spoke to a delivery courier, and their children mingled with classmates in school. How can we be sure the checkout screen was to blame?

A year of intense scientific research has given us some valuable clues about how the coronavirus spreads.

Surfaces (fomites)

There’s little doubt that coronavirus can theoretically spread through commonly-handled physical objects or surfaces that become ‘infected’ with the virus – known by epidemiologists as ‘fomites’. Yet recently some scientists have said too much emphasis has been placed on fomites. In a review of research published in The Lancet in July, Emanuel Goldman, a microbiologist at Rutgers New Jersey Medical School, said some government advice about deep-cleaning surfaces was “thin and probably flawed”. Most of the research at that point was carried out in controlled laboratory settings, using huge amounts of the virus, he said – not necessarily a realistic environment. He thinks the trend of people using harsh chemicals to deep-clean their post was probably unjustified – although he added that hand-washing and sanitiser is still a good idea.

And an editorial by the journal Nature earlier this month advised: “Catching the coronavirus from surfaces is rare. The WHO and national public health agencies need to clarify their advice.”

Hunter says: “It’s an entirely plausible route of infection, but it’s been difficult to prove it beyond any shadow of doubt.” Photographs of health officials in hazmat suits disinfecting streets and bridges, as seen in Spain, Italy, China, and various other countries, “fills me and most of my colleagues with more than a little amusement,” he adds.

Many of the best studies on transmission were carried out at the beginning of the pandemic, because later on the virus became so widespread it became difficult to isolate specific routes of transmission. In a small study carried out last February, for example, researchers took swabs from various surfaces in a Wuhan hospital that was treating a high number of Covid-positive patients. They found virus particles on computer mice, bins, bed handrails, doorknobs and even on the soles of medical employees’ shoes.

Another study published in the New England Journal of Medicine found the virus can survive for up to 72 hours on plastic and stainless steel, eight hours on copper, and four hours on porous surfaces like cardboard.

But a year into the pandemic, epidemiologists are still to find concrete cases in which fomite transmission was clearly to blame. As long ago as July, a WHO report said fomites are a “likely” route of transmission, but found “no specific reports” of somebody catching the virus this way – although the scientists noted it was “difficult to discern” the difference between fomite transmission and other forms of transmission. Since then, no slam-dunk evidence has emerged, says Hunter.

Close contact droplets

Scientists generally agree that respiratory droplets, transferred via close contact between people, are the most likely route of transmission.

When you cough or sneeze, you emit thousands of droplets, like rain. They are essentially tiny drops of saliva (scientists only call them droplets because they are invisible to the naked eye). They can fly about three feet before dropping to the ground, or six feet if the cough is particularly forceful.

These droplets contain particles. The largest and heaviest of the particles will fall straight to the ground, while the smallest, known as aerosols, will continue to float about in the air for some time (see below). It is those larger, heavier particles that cause the bulk of Covid transmission, scientists say. If they land on a wet part of your face, you risk becoming infected.

Singing or speaking loudly is thought to be particularly risky, because it extends your ‘breath range’ – the distance you expel droplets in your breath. In March, US authorities reported an outbreak at a choir in Skagit, Washington; of the 121 members who attended two rehearsals (on March 3 and 10), 53 became ill with Covid and two died (this at a time when Covid was relatively rare in the West Coast state).

Hunter says the main risk from droplet transmission comes from “indoor, crowded environments, where people don’t socially distance. And if they’re singing, then that increases the risk as well.”

Airborne transmission

Whilst scientists agree that you can easily catch coronavirus from larger cough droplets exchanged at close range with an infected person, a far more controversial question is whether you can catch the virus from tiny, airborne particles, known as aerosols.

The key point about aerosols is that they float about in the air for hours, meaning you could theoretically catch the virus despite having no contact with an infected person – if you walk into a train carriage where an infected person was standing several hours ago, for example. The bacterium that causes tuberculosis and the viruses that cause measles and chickenpox are all commonly spread through aerosols.

Last spring, most of the scientific community was sceptical that airborne transmission played any meaningful role in the spread of Covid. But the pandemic has seen a gradual shift in thinking; last summer, 239 scientists in 32 countries wrote an open letter to the WHO, urging the body to take airborne transmission more seriously.

Now, scientists in the WHO and the Centers for Disease Control, the influential American equivalent of Public Health England, say aerosol transmission is possible – but much less likely.

In study on Covid published in May in the journal Nature Research, researchers set up ‘aerosol traps’ around two hospitals in Wuhan, and found bits of the virus’s genetic material floating around indoor toilets, as well as a room in the hospital where medical staff removed their masks, gowns, and gloves. Researchers said their findings support the idea that Sars-Cov-2 particles might be able to hang around in the air for hours, highlighting the importance of good indoor ventilation. The study did not try to answer whether those virus particles were actually causing infection (they might have been dead or degraded particles).

Another investigation, of a restaurant in Guangzhou, China, found traces of Sars-Cov-2 in the air conditioning system – suggesting that particles of the virus were being blown about the restaurant. The restaurant became the target of investigation after one diner was found to have infected nine others while eating there.

But as with fomite transmission, scientists have found very few concrete cases in which it was clear that aerosols played a role in transmission.

WHO advice published in October said: “Aerosol transmission can occur in specific settings, particularly in indoor, crowded and inadequately ventilated spaces, where infected person(s) spend long periods of time with others, such as restaurants, choir practices, fitness classes, nightclubs, offices and/or places of worship.”

Last year Germany added regular ventilation of rooms to its formula for tackling coronavirus, with opening windows hailed by Angela Merkel as one of the “cheapest and effective ways” of fighting the virus.

Other forms

Scientists say it may be possible to catch Covid from urine or faeces – but this is much less likely than other forms of transmission, and again there have been no reported cases.

Source http://www.telegraph.co.uk/

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Are you ready for the end of lockdown?

Finding the time to read this article could save a life. 

The Use of Ozone to Protect Care Home Residents and Staff  

The fight to keep the coronavirus out of our residential care homes and managing a virus breakout is a tough and ongoing battle. For those that have already had infections within the home it is imperative that. 

With the elderly residents being some of the most vulnerable in our society, it is extremely hard work to keep on top of all the extra measures put in place to help protect them and keep them and the staff safe from being infected with COVID.  

While restrictions may have been put on families from visiting care homes, regular deliveries from suppliers are still needed. Food, PPE, cleaning & medical supplies are being delivered, on a daily basis, in some cases.

All inbound deliveries have to be wiped down, disinfected and sanitised before being taken into the main building. Wiping down the items can take some time and leaving the deliveries in a room for at least 24 hours can also be problematic. 

A more efficient option that can save considerable time, effort and money is an Envirosafe Ozone Generating machine. 

Deliveries are put into a closed room, the Envirusafe unit is then turned on and begins to produce ozone gas that will then begin its work by permeating, sanitising and sterilising the air and everything it touches, 

Ozone is the strongest disinfectant available, more than 50 times stronger than other disinfectants, including chlorine, and it works up to 3,000 times faster!

Ozone cannot be stored and is produced at the point of use, on-site, using an ozone generator, and they cost less than a light bulb to run making them very cost effective. 

Virtually anything can be sanitised and disinfected using ozone and, unlike chemicals, there are no toxic residues that need to be monitored, making the Envirusafe range of units ideal for the sanitisation of pharmaceutical equipment, PPE, staff uniforms, medical supplies and fresh food deliveries.  

Not only will ozone disinfect surfaces, food, water, clothing and other items is also very effective at destroying airborne viruses, pathogens and microorganisms and can be used as a way to provide an added layer of protection in areas that are prone to high traffic. Entrance halls, waiting rooms, communal areas, treatment rooms, washrooms and toilets can all be treated with ozone.  

Another benefit of ozone is that, until now, there has been no evidence that any microorganism, virus or bacteria has been able to build resistance to ozone unlike other chemical disinfectants that are used.

There are 3 basic types of ozone generators that we produce. 

Low level units – The low level ozone generators produce low levels of ozone. These units are installed permanently into bathrooms, meeting rooms, kitchens, wash rooms and toilets and are operated on a timer to continually keep the areas santised. These are especially useful for items like door handles, for example, where cleaning after every time the handle is touched is impractical. 

Fan assisted units – The larger ozone generators are used to shock treat rooms and larger spaces and as a fast way to disinfect deliveries, food, clothes, furniture, equipment and uniforms, PPE and other objects and equipment. Items are placed in the room and the ozone generates higher levels of ozone that sanitises, disinfects and sterilises everything it touches. 

Piped Systems – The piped units produce high levels of ozone that can be piped into confined spaces like buses, coaches, cars, cupboards and storerooms. You can ozonate water which can then be used as a liquid disinfectant to wipe down surfaces and to sterilise fruit and vegetable 

Envirosafe Ozone Sanitiser Uses in a Care Home Environment 

  • Disinfect inbound supplies and deliveries
  • Disinfect and sterlise staff uniforms and PPE including N95 masks at the end of the shift.
  • Shock treat rooms that have been occupied by those infected with COVID19
  • Treat day rooms, communal rooms and thoroughfares at the end of the day  
  • Ongoing disinfection of bathrooms, toilets, washrooms, kitchens and meeting rooms 

Ozone has been used commercially for many years to sanitise sewage water and food processing plants, breweries and even fishing trawlers. 

Ozone is also an excellent deodoriser removing stubborn smells like urine, vomit, sour milk and faeces as well as tobacco smoke, mould and damp smells. 

For more information contact

Bob Long – Head of Technical 

Posted on

Press Release – Envirusafe Helping Businesses In Their Fight Against COVID19

FOR IMMEDIATE RELEASE: 27th January 2021  

Contact: Bob Long
Company: Envirusafe
Telephone: 01925 321 888
info@envirusafe.co.uk
www.envirusafe.co.uk

Envirusafe Helping Businesses With Their Fight Against Covid-19

Envirusafe, Thornton, Lancashire: Recently launched its latest range of wall mounted sanitisers designed to provide an extra layer of protection to businesses against the coronavirus.

The Mountain Fresh Ozone Sanitisers have been used for many years, predominantly as effective deodorizers but, due to their use of ozone, which is a very powerful disinfectant, the units are now being used to aid in the fight against the COVID-19 virus.

The units produce low levels of ozone gas which has been scientifically proven to destroy the coronavirus on contact, sanitising the air and disinfecting the surfaces it touches.

Ozone works by oxidising and destroying the outer protein shell of the virus on contact.

Bob Long, head of technical said “ozone is the most powerful disinfectant known to man and yet virtually no one knows about it” It is 50 times more powerful than the strongest disinfectant, only extreme heat beats it” He added. “By installing and running these small units in communal areas in care homes, shops, offices, meeting and conference rooms, public toilets and kitchen areas they help to keep the air and surfaces free from viruses and bacteria, slowing the spread of infections down”.

Bob was also quick to say, “This is not a magic wand, it does not replace a good cleaning regime. This is another tool in your arsenal to combat the virus and protect yourself, your staff and your customers”.

Residential care homes have been very badly hit by COVID and a prominent care home in Lytham St Anne’s which had an outbreak, recently installed our units throughout the home and were so impressed they have now installed them at another of their homes in Wales with further units soon going into their places in Scotland. A spokesperson for the homes said the first thing they noticed was how fresh the areas that were being treated smelt.

Benefits of the EnVirusafe Ozone Sanitisers include.

  • Easy to install
  • Virtually no running costs
  • No chemicals needed
  • Leaves no toxic residue
  • Unused ozone reverts to oxygen
  • Powerful, Fast and effective
  • Safe to be used in food processing areas
  • Built in timer
  • Works 24/7 automatically sanitising the air and the surfaces the ozone touches
  • As a gas, it gets into all the hard to reach or inaccessible places.

Further information on our product range can be found on our website

www.enVirusafe.co.uk
147 – 149 Victoria Road East
Thornton, Lancashire
FY5 5HH  
info@envirusafe.co.uk  
+44 (0) 1925 321 888

Posted on

Ozone, is it the Best Kept Secret Killer of the Coronavirus?

Ozone, is it the Best Kept Secret Killer of the Coronavirus? 

The speed that the COVID-19 virus spread took the world by surprise and there is no doubt it is here to stay for the foreseeable future. It has changed the way we live, probably forever.  

Every corner of the world has been affected with many millions of people infected. It is imperative that we do all that we can to try to help slow the spread of this disease down.  

The pandemic has had people scrambling for effective ways to protect their staff and customers  and keep them safe. Primarily this is being achieved through new processes and cleaning  regimes which is obviously different for each type of business. One very important thing is to  find an efficient way to disinfect and sanitise their business.  

Ozone is fast becoming the go-to option and could very well be the best kept secret killer of  Coronavirus. There have been numerous scientific studies that have proven that ozone not only kills the coronavirus but over 99% of bacteria, other viruses and pathogens in the air and on surfaces and objects. It was highly effective against the SARS outbreak at the beginning of the2000s, and it can do the same for COVID.  

The thing is, apart from food processing companies, brewers, fishing trawlers and water  treatment plants very few people have actually heard of or understand just how good ozone  sanitisation is.  

However, this is changing as more and more people discover just how easy and effective using  ozone as part of their cleaning regime is.  

What is Ozone?  

Ozone is basically gaseous oxygen with one extra oxygen atom. Ozone can quickly oxidise and  destroy organic materials. It begins work instantly destroying the airborne pathogens, bacteria,  viruses and mould in seconds.  

Ozone is heavier than air and it continues its work as it lands on surfaces and objects in the  room including all of those hard to reach and inaccessible places. This is why it can be used very  effectively to disinfect and sanitise all sorts of surfaces.  

All you need is a machine that generates ozone, and we have you covered there. There are basically 2 different types of ozone generators you can use.  

Low Concentration Sanitisers

These produce low levels of ozone and can be used 24/7 continuously sanitising the area that  they are installed. These units are ideal for wash rooms, toilets, shower blocks, changing rooms  hallways and stairwells for example. 

High Level Ozone Sanitisers  

These ozone generators are designed to shock a room and can be used in almost any home or  work environment. They are used to sanitise and disinfect offices, hotel rooms, reception areas,  shops, kitchens, pubs, bars and restaurants, nursing homes, hospitals, schools, nurseries and  any other area where you need to keep clean and sanitised.  

Once the area has been cleaned down, the ozone sanitising unit is switched on, and the room is  vacated. Leaving the ozone to do its job. Once it is finished, between 20 minutes and an hour,  (depending on the size of the room) the room is then aired and ready to use.  

The Difference Between Cleaning, Disinfecting & Sanitising 

Methods such as pressure washing are going to be very effective in being able to deep clean  your business and soap, water and good old elbow grease are also proven methods of cleaning,  though, is not exactly the same thing as sanitising. In this case, the benefits that you can get  from using an ozone generator are far better than you are going to be able to achieve with  conventional cleaning methods.  

When you clean, you have one goal in mind; turn something that looks dirty into something  that is sparkling clean. If you are disinfecting or sanitising, you are trying to kill germs and  bacteria that live within every surface and object as well as in the air that we breathe. While  sanitising an area may not provide results that are easy to see and feel, this process is essential  as part of your efforts against Coronavirus.  

Is Ozone Safe To Use? 

Ozone has a very distinct smell when a generator produces it; you are most likely going to be  able to smell it in the air and know that the ozone generator is doing its job of sanitisation.  

As with any powerful disinfectant, you need to take precautions when using the larger ozone  generators. Unlike chlorine or sodium hypochlorite, which can leave toxic residue on your  surface’s ozone reverts to oxygen and, once dissipated, leaves no residue making it  entirely safe to use in every area and every type of business. 

Should I Be Looking At Ozone As A Viable Way To Combat COVID-19? 


Disinfecting your business or home with ozone generators can undoubtedly go a long way in  keeping the airspace free of COVID-19. That means you can relax with some other measures that you might take to prevent it. Keeping all the different objects in and around  your house clean can also help.  

Using an ozone generator in the right dosage is not going to harm you, your staff or your  customers. At the end of the day, we are talking about a low-risk, high reward method that can  allow you to sleep better at night.  

It is powerful, effective and fast, so using ozone can be a win-win and help you in the fight  against coronavirus.

Posted on

Envirusafe Helping Businesses In Their Fight Against Covid-19

FOR IMMEDIATE RELEASE: 27th January 2021  

Contact: Bob Long
Company: Envirusafe
Telephone: 01925 321 888
info@envirusafe.co.uk

www.envirusafe.co.uk

Envirusafe Helping Businesses in Their Fight Against Covid-19

Envirusafe, Thornton, Lancashire: Recently launched its latest range of wall mounted sanitisers designed to provide an extra layer of protection to businesses against the coronavirus.

The Mountain Fresh Ozone Sanitisers have been used for many years, predominantly as effective deodorizers but, due to their use of ozone, which is a very powerful disinfectant, the units are now being used to aid in the fight against the COVID-19 virus.

The units produce low levels of ozone gas which has been scientifically proven to destroy the coronavirus on contact, sanitising the air and disinfecting the surfaces it touches.

Ozone works by oxidising and destroying the outer protein shell of the virus on contact.

Bob Long, head of technical said “ozone is the most powerful disinfectant known to man and yet virtually no one knows about it” It is 50 times more powerful than the strongest disinfectant, only extreme heat beats it” He added. “By installing and running these small units in communal areas in care homes, shops, offices, meeting and conference rooms, public toilets and kitchen areas they help to keep the air and surfaces free from viruses and bacteria, slowing the spread of infections down”.

Bob was also quick to say, “This is not a magic wand, it does not replace a good cleaning regime. This is another tool in your arsenal to combat the virus and protect yourself, your staff and your customers”.

Residential care homes have been very badly hit by COVID and a prominent care home in Lytham St Anne’s which had an outbreak, recently installed our units throughout the home and were so impressed they have now installed them at another of their homes in Wales with further units soon going into their places in Scotland. A spokesperson for the homes said the first thing they noticed was how fresh the areas that were being treated smelt.

Benefits of the EnVirusafe Ozone Sanitisers include.

  • ·  Easy to install
  • ·  Virtually no running costs
  • ·  No chemicals needed
  • ·  Leaves no toxic residue
  • ·  Unused ozone reverts to oxygen
  • ·  Powerful, Fast and effective
  • ·  Safe to be used in food processing areas.
  • ·  Built in timer
  • ·  Works 24/7 automatically sanitising the air and the surfaces the ozone touches
  • ·  As a gas, it gets into all the hard to reach or inaccessible places.  

Further information on our product range can be found on our website

www.enVirusafe.co.uk

147–149 Victoria Road East
Thornton, Lancashire
FY5 5HH  
info@envirusafe.co.uk  
+44 (0) 1925 321 888