Velly intellesting…….
Is air conditioning as a genre , safe ?
A mechanical engineer explains why cruise lines are so prone to spreading the coronavirus and why hospital ships are safer :
Luxury cruise ships like Carnival Corporation’s Diamond Princess have proven fertile ground for the spread of COVID-19. In contrast, two naval hospital ships -if operated with certain precautions – should safely halt transmission, says Qinyang Chen, a professor of mechanical engineering at...
www.businessinsider.com.au
Sorry I missed this before. The article is wrong.
Is air conditioning as a genre , safe ? = YES
Properly designed and constructed AC does not spread coronaviruses.
Yes hospitals have better AC than ships or average buildings. But hospitals are concerned about many things, and many diseases. The AC is hospitals will also vary depending on what part of the hospital it is. ie for diseases that have true aerosol transmission like measles or CV 19 IF there are invasive procedures occurring with the patient. ie Intubation.
Now diseases can be a problem with AC. But it is mainly bacteria driven ones that can occur on some types of AC (particularly large evaporatitive) when bacteria driven diseases like Legionnaires can occur. There are various ways to control this. Some are chemical and there are other ways. As I am involved in training those that maintain large buildings (this is all types including hospitals, aged care, offices aquatic centres) including all building services including AC I spoke at length here in Melbourne with a Singaporean based company last November who had developed a new system to prevent Legionarres in large AC systems. Monitoring how Building Services should be operated and maintained is something that I have been with involved with for over a decade.
As I have reported earlier with SARS there was one well researched building where air transmission did occur of SARS in a cluster. This however had faulty sewer risers and fans that were fans and that were improperly installed by the occupants in their bathrooms/toilets which in essence blew that contaminated air short distances fro the contaminated sewer risers with the apartment.
So if you live or work in a building with a properly designed and maintained AC please do not panic or fear it with respect to Covid 19.
With Covid 19 what you need to watch, as is now well known, is to take care with transmission from hard surfaces such as doorknobs etc in public areas. Wash your hands regularly. Avoid being cough on, and maintain minimum of 1.5m spacing.
Cruise ships:
- Will have had on the ships infected persons wandering around spreading CV 19 (ie as with Diamond Princess where the source had been on the ship for an extended period before lockdown. Most likely too then further newly infected persons wandering around).
- Fomite transmission from infected crew and re-use of trays, trolleys etc (Those in quarantine now normally will be given food in a way where things are disposed of and not re-used)
Now many things can be possible. But what is probable is a much smaller list.
PS: Corana viruses are not new. The flu kills 250-500,000 people every year. AC is built with the flu in mind. While there are differences between the flu and CV-19 it is currently thought that CV-19 is not normally spread as a true aerosol (ie can float) but is like the flu attached to a droplet (moisture or mucus) which causes it to sink and land on surfaces. Hence the 1.5m separation rule and also why it is not spread through ducted building AC as the total length of the ducts to draw the air in and then return it is quite lengthy.