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COVID-19, in the Air & on the Surface


Critical new research by the National Institutes of Health (NIS) indicates that COVID-19, a strain of the Coronavirus, can survive in the air and on surfaces for extended periods of time.


The research found that the virus can survive for up to 4 hours on copper, up to 24 hours on cardboard, and 2 to 3 days on plastic and stainless steel.


In addition to contact, the transmission of this virus is also plausible through the air as it was identified that the virus can live in the air for 3 hours in an aerosolized form.


Recently, the use of face masks has become not only recommended but mandatory, such as the state of Vitoria in Australia, who is now facing the second wave of the virus, which is sweeping through the state like wildfire. Ensuring you have an approved and laboratory tested face mask will ensure the best protection. It’s also important to note that if you are not using disposable masks, where you regularly dispose of the used one and replace with a fresh hygienic new one, then it is relevant to know if the mask was manufactured to the correct certification specifications as well as how to correctly sanitise your reusable masks.


Vapor containing the virus can be introduced into the air by a simple sneeze, cough or simply speaking. Its for this reason that the use of a mask is a smart one! However, simply wearing a mask alone is not the key to eliminating the virus. Regular hand washing is also required to ensure that when you put the mask on and off, that there is no transfer of the virus from your hands to either your nose, mouth or the mask itself.


Relying on social distancing alone can be a concern when you take into account a person sneezing can transmit vapor from their mouth containing the virus and propel it up to 27 feet (8.2 meters) away at up to an astonishing one hundred miles an hour (160.9km/hr).


What other options do we have when dealing with the virus in the air?

Research shows that Ozone gas has been successful in treating the SARS-COV-1, a virus of the same family as COVID-19, the Coronavirus family, which led to the epidemic in 2003.


Ozone is also widely used in sterilizing equipment in hospitals against bacteria as well as purifying the bottled drinking water provided to their patients.


As discussed in a previous article, Viruses-deactivated & destroyed by secondary sanitation technology, COVID-19 is an enveloped virus containing RNA. Ozone can oxidise (destroy) the virus by breaking through its outer layer and damaging the RNA core, rendering it harmless to a potential host (us).


So, what do we know about Ozone gas and COVID-19? Research would suggest that exposure in to a sufficient dose over a given period of time, COVID-19 would be eliminated from open spaces as well as shadows and crevices in the air and surfaces in the treated environment.


Written by: John Morrison BSc




Viruses- deactivated & destroyed by Secondary Sanitation Technology


“Viruses are the smallest of all the microbes. They are said to be so small that 500 million rhinoviruses (which cause the common cold) could fit on to the head of a pin. They are unique because they are only alive and able to multiply inside the cells of other living things. The cell they multiply in is called the host cell.

A virus is made up of a core of genetic material, either DNA or RNA, surrounded by a protective coat called a capsid which is made up of protein. Sometimes the capsid is surrounded by an additional spikey coat called the envelope.”

When it comes into contact with a host cell, a virus can insert its genetic material into its host, literally taking over the host’s functions.

An infected cell produces more viral protein and genetic material instead of its usual products. Some viruses may remain dormant inside host cells for long periods, causing no obvious change in their host cells (a stage known as the lysogenic phase). But when a dormant virus is stimulated, it enters the lytic phase: new viruses are formed, self-assemble, and burst out of the host cell, killing the cell and going on to infect other cells. Viruses attack bacteria, known as the lambda bacteriophage, which measures roughly 200 nanometers.


So, with all that being said, how are viruses treated in our local swimming pools?

If the local pool water is treated with only chlorine (1ppm Free chlorine, pH 7.5 and Temp 26 degrees Celsius), according to the CDC, it takes approximately 16 minutes for viruses to be killed. Viruses are chlorine resistant, meaning they are not easily destroyed by chlorine alone.

Whilst most Australian commercial pools operate at levels higher than 1ppm of chlorine, they also often have water at temperatures higher than 26 degrees Celsius and have the most important variable, pH, to consistently maintain to ensure there is more active chlorine (Hypochlorous Acid) than there is inactive chlorine (Hypochlorite Ion) in the water.

However, if your local pool has a form of ‘secondary sanitation’ equipment fitted to its plant room, which is not reliant on maintaining constant pH levels to be effective, then the risk of a swimmer contracting a virus is significantly decreased.


What is secondary sanitation?

Secondary sanitation is the second line of defense for chlorine (primary sanitiser) and is highly recommended for use on every public pool by the health departments in every state and territory of Australia as it provides the most effective treatment when it comes to the smallest pathogens such as viruses.


What types are there?

There are three main types of secondary sanitisers used, which are listed below from least oxidation potential through to the greatest oxidation potential;

1) Ultraviolet Light (UV)

2) Ozone gas (O3)

3) Advanced Oxidation Process (AOP), which combines UV and Ozone technology to produce Hydroxyl Radicals.


How does Ultraviolet Light (UV) work?

Anne Rammelsberg, a chemistry professor at Millikin University, offers this explanation:

Ultraviolet (UV) light kills cells by damaging their DNA. The light initiates a reaction between two molecules of thymine, one of the bases that make up DNA. The resulting thymine dimer is very stable, but repair of this kind of DNA damage – usually by excising or removing the two bases and filling in the gaps with new nucleotides is fairly efficient. Even so, it breaks down when the damage is extensive.

The longer the exposure to UV light, the more thymine dimers are formed in the DNA and the greater the risk of an incorrect repair or a “missed” dimer. If cellular processes are disrupted because of an incorrect repair or remaining damage, the cell cannot carry out its normal functions. At this point, there are two possibilities, depending on the extent and location of the damage. If the damage is not too extensive, cancerous or precancerous cells are created from healthy cells. If it is widespread, the cell will die.

How does Ozone gas (O3) work?

Ozone (O3) is formed when a high-voltage arc passes through the air between two electrodes. It is also formed photochemically in the atmosphere, and it is one of the constituents of smog. Ozone is a bluish and toxic gas with a pungent odor. Ozone is unstable because it breaks down to give molecular oxygen. Its low solubility and instability require that it is to be generated on site and introduced into the water as fine bubbles.

How does Advanced Oxidation Process (AOP) work?

Conventional oxidation processes are used in water treatment to disinfect water, to reduce toxins, odour and colour or to reduce manganese and iron levels in potable water. These processes may not destroy all toxins and have the potential to create dangerous disinfection by-products (DBPs). Advanced oxidation process (AOP) utilises the strong oxidising power of hydroxyl radicals that can reduce organic compounds to harmless end products such as oxygen.

Oxidation is defined as the transfer of one or more electrons from an electron donor(reductant) to an electron acceptor (oxidant) which has a higher affinity for electrons. These electron transfers result in the chemical transformation of both the oxidant and the reductant.

In advanced oxidation processes AOPs the hydroxide radical, OH not the OH¯ hydroxyl ion as in bases, is produced in a first step. This molecule has a very strong oxidizing and disrupting ability that may, depending on conditions, turn a complex (recalcitrant or refractory), organic molecule into CO2 and H2O.

The first reaction of OH with many volatile organic compounds (VOCs) is the removal of a hydrogen atom, forming water and an alkyl radical (R). OH + RH  H2O + R Oxidation reactions that produce radicals tend to be followed by additional oxidation reactions between the radical oxidants and other reactants, (both organic and inorganic), until stable oxidation products are formed.

AOPs are reactions where first, hydroxyl radicals are produced, secondly, these radicals react with and destroy degradable organic and inorganic compounds. Typically, methods such as Ultraviolet light (UV), Ozone gas (O3), Hydrogen peroxide H2O2, Fenton’s and titanium dioxide TiO2 are combined (synergistic effect) to increase OH formation. Combining methods increases reaction rates 100 – 1000 times compared to using either ozone, H2O2 or UV alone.

Written by: John Morrison BSc



Emiliana, C. Extinction and Viruses. BioSystems 31: 155-159. 1993.

Microbiology Society. Viruses. 2020.

Centre for Disease Control and Prevention (CDC), May 4, 2016.

Scientific American. How does ultraviolet light kill cells? 2018.

Washington University. Why is ozone such a good oxidizing agent? General chemistry lab tutorial. 2001.

Dr Bill Grote. Application of Advanced Oxidation Process (AOP) in water treatment. June 2012.

Department of Health and Human Services, State of Victoria. 2019

Department of Health, New South Wales Government. 2013.

Department of Health, Government of Western Australia. 2020.

Department of Health, Queensland Government. 2019.

Department of Health, Northern Territory Government. 2006.

Department of Health, Australian Capital Territory Government. 1999.

Department of Health, South Australia Government. 2013.


Swimming with Asthma


Is swimming a good activity for young Asthmatics?

It’s well documented that regular swimming activity can be great for those suffering with the medical condition known as Asthma.

“Asthma is a medical condition that affects the airways (the breathing tubes that carry air into our lungs). From time to time, people with asthma find it hard to breath in and out, because the airways to the lungs become narrower – like trying to breathe through a thin straw”.

This is a condition that I in fact suffered at a young age. I would randomly and uncontrollably cough and splutter, which left me gasping and struggling for air at times. This was especially so when my heart rate increased from participating in various types of exercise. And being an active kid who loved sports, this was an ongoing problem and a real handicap. I remember what an amazing feeling and relief it was to breath normally again, thanks to multiple puffs on my Ventolin inhaler.

Compared to other sports, swimming has been found to less likely trigger Asthma. The recumbent exercise of swimming can also produce a greater central blood flow than upright forms of exercise.

Some studies have shown that young asthmatics participating in regular swimming activities resulted in a decrease in the frequency of wheezing days, a decrease in the days needing medication, a decrease in emergency room visits, and an increase in school attendance.

Interestingly, in each of the Olympic Games between 1956 and 1972 there were gold medalists who had Asthma, which just shows not only can you enjoy the benefits of swimming with Asthma, but you can even excel in the sport.

But what if the water quality is poor?

Whether you suffer from Asthma or not, poor water quality can significantly affect your health but especially so for Asthmatics. Some studies suggest that healthy children can have their lung epithelium damaged and promote the development of Asthma as a result of swimming in poor water quality of both indoor and outdoor swimming pools.

What issues with poor water quality should you be concerned about?

Nitrogen trichloride (Trichloramine) is a disinfection byproduct (DBP) produced when chlorine, commonly used as a sanitiser in pools, reacts with urea (ammonia product), which comes from sweat and urine constantly released by swimmers. This chlorine byproduct can cause irritation of a swimmer’s airway, especially if already suffering with Asthma, as well as irritate the eyes.

Haloacetic acids (HAA’s), another DBP formed when chlorine reacts with organic products released by swimmers. Some HAA’s are considered ‘possibly carcinogenic to humans’, according to the World Health Organisation (WHO). 

Are the benefits of the swimming activity outweighed by other risks to one’s health?

It’s no doubt that swimming is a good physical activity for Asthmatics, but only if the water quality is healthy via the correct methods of water treatment that remove not only dissolved chlorine disinfectant byproducts (DBP) but also the gasses too. Such treatment methods include Ozone and Advanced Oxidation Process (AOP).

Written by: John Morrison BSc


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