28/09/2020
People try to fight the Coronavirus pandemic in their locations, using the available prevention measures, with varied results. I have seen many institutions spending large sums with very little results, with the sad consequence of infections and deaths. There are published metrics about air renewal, in relation to building size, temperature, humidity and occupancy. Cleaning and disinfection are important, and social distance measures are in order.
I created a Building Health Calculator, located at http://netic.com.ar/coronavirus/ , with the mean factors affecting building safety regarding Coronavirus COVID19 .
First, you need to enter the building measures. These are important because they will limit the number of people inside at any given moment. They also influence the volume of air that must circulate thru the building to ensure clean air. Width and length define the surface, and we usually allow 3 square meters per person. The height is less important but it is used for the air volume calculations. In some places there is vertical air circulation, making the high places part of the important volume to be considered in calculations. In others, the room near the ceiling is isolated, particularly in high temperatures when the hot air stays in the top.
Humidity influences the virus transmission. Dry places let micro droplets stay in the air longer, while moisture favors heavy drops that tend to fall to the floor and lose infective power.
High temperatures shorten the virus survival, while cold weather allows virus to survive hours or days.
Air renewal is the easiest form to make a building secure. It decreases virus concentration, which is the main factor that contributes to human infection with COVID19 and similar respiratory viruses. Air recirculation inside a building is useful, but fresh air income and external drain are better.
Cleaning is another factor that influences the infection rate inside a building. Hand cleaning is more common, but a method called High Volume Fogging is better, because it creates a very fine fog with some chemical disinfectant that reaches every spot in minutes, without the human effort of brushing or sweeping. I try to convince building owners to improve ventilation, because the spend money once and then let the fans do the job, instead of spending money many times per week with cleaning people and equipment. Cleaning has been overvalued. It is very unlikely that someone gets the virus from walls and floor. Nobody licks the walls. Even if someone touches an object and then takes the hand to the mouth or eyes, the contagion chances are not so high.
The calculator gives an index for the main building factors that influence coronavirus transmission. 5 means the building is safe. Higher values mean that there are factors that need to be modified to improve viral safety.
I am providing advice to institutions everywhere on Coronavirus control. I have worked with dangerous viruses in the laboratory, covering ways of virus transmission and animal infection and disease.
Ask me about your situation.
epidemiology consultant, virology consultant, immunology consultant, covid19 control, coronavirus control
