Surface sanitation in emergency by Coronavirus
In recent days we have focused on the self-production of hand sanitizing gel. However, the need to disinfect cannot and should not be limited to the hands, the environment in which we live must also be kept under control.
Many people ask me how and what to do to sanitize the environment in which we live or work. Here are some simple guidelines for tackling and solving the problem.
The first consideration to make is to understand why it is necessary to disinfect the surfaces of the living environment. A well-known magazine, New England Journal Of Medicine, has recently published a study with an unequivocal title: Air, Surface Environmental, and Personal Protective Equipment Contamination by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) From a Symptomatic Patient. For those who wish, the article is available at this address: https://jamanetwork.com/journals/jama/fullarticle/2762692
From studies like this and collecting the opinions of the experts, the Istituto Superiore di Sanità has issued very precise guidelines. I repeat that these official indications have been absolutely respected and followed with regard to the alcoholic gel. For hard surfaces, the ISS defines some very important aspects:
Quaternary ammonium salts based products are not recommended because these products, the various "forms" need time, at least 30 minutes, to act. I also add that microorganisms can get used to these molecules, that is, exactly as with antibiotics used for humans, resistant strains can be selected.
The ISS recommends only one disinfection system and this system is based on sodium hypochlorite. This substance is very polluting and creates very stable chlororganic compounds that is practically non-biodegradable. But we are in a situation of serious danger and we cannot give up a substance that is easily available, cheap, extremely effective and that has an action mechanism to which germs, bacteria and viruses CANNOT BE USED. Therefore sodium hypochlorite formulations should be used.
It is necessary to distinguish between large surfaces (floors, stairs, entrances, balconies and window sills, etc.) and small surfaces (door handles, handrails, toys, PC mouse, mobile phones and computers…) need a sanitizer and a system of application, with different characteristics.
The large surfaces can be left to dry without rinsing while the small ones must at least be dried with paper or rinsed. Just think of a children's toy, children who often put toys in their mouths.
Formulation for Large Surfaces: You must buy a normal bleach at the supermarket, do not take the first price or the most expensive, stay on an average product. At this point, take a bucket, absolutely plastic, not metal, and put about 3 liters of tap water in it. To this water add a kitchen glass, filled with bleach (the final solution will be about 0.1% of active chlorine). You can also add two tablespoons of floor detergent in order to increase the penetration of the sanitizing solution even in the most hidden interstices. Avoid contact with any metal, metals and iron in particular, do not like sodium hypochlorite which, in the presence of iron ions, decomposes quickly.
Do not rinse because the longer the disinfectant solution remains active, on the hard surface, the better!
This preparation is unstable and therefore must be prepared from time to time as needed.
Formulation for Small Surfaces and Objects: The same bleach is always used but the dilution is lower. That is, a glass of bleach should be used in half a liter of tap water (the final solution will contain about 0.5% active chlorine). Also in this case a teaspoon of dish detergent helps the distribution of the product.
This formulation, more concentrated than the previous one, must be used using absolutely gloves and goggles. The windows must be open.
For objects certainly resistant to hypochlorite, such as a plastic object, you can spray the liquid directly on the object, let it act for at least a minute and dry / rinse. For electrical objects, such as elevator pushbuttons, personal computers, cell phones, etc., instead, it is preferable to wet the disposable paper and go with that on the surfaces. This will prevent short circuits.
This solution remains active for two / three days, besides it must be redone from scratch.
Hydrogen peroxide and peracetic acid are excellent disinfectants but very dangerous in their handling. I don't want to contribute in any way to any domestic accidents, so I won't talk about it. I hope you understand it.