On Saturday morning, the astronauts aboard the ISS spend a few hours cleaning the station to prevent bacterial and fungal growth. But how does a cleaning day go over the Earth, in concrete terms?
The weekend aboard the resort is relatively quiet. To facilitate the astronauts’ rest during these two days, the on-board cameras are not configured to broadcast a live feed, while calls from the control center are rare, and usually contain only brief communications. This allows residents to relax as they see fit. Well, not quite.
In fact, the crew devotes three to four hours of their Saturday morning to cleaning their environment to avoid the proliferation of fungi, molds and other bacteria.
Wipes and cleaning of ventilation grilles
The control of microorganisms is naturally essential on board the ISS. According to some studies, some are doing even better in this microgravity environment than on Earth. Also, everything is done to avoid unnecessary risks.
“We must disinfect all the surfaces we touch every week“, Recently explained Frenchman Thomas Pesquet, who arrived on site on April 24 for his second mission in orbit. Some measures, he added, “are similar to those you might find in hospitals or airports to prevent the spread of bacteria“.
Handrails, microphones, computers… To clean all surfaces regularly touched, astronauts use disinfectant wipes. As a rule, it is the current Station Commander who assigns each area to be cleaned.
“The most difficult modules to clean are certainly Node 3, where we have the toilets and exercise equipment, and Node 1, inside which we eat.“, Italian astronaut Samantha Cristoforetti once clarified in a item blog. Usually, astronauts take turns cleaning the dirtiest modules.
Residents should also regularly vacuum the ventilation grilles, inside which any small debris floating in the cabin ends up being washed away. Again, this is essential. A blocked ventilation grid could indeed interfere with the station’s carbon dioxide purification mechanisms, rendering the air inside unsuitable for breathing.
As the growth of harmful microorganisms in an environment as closed as the ISS can threaten the physical integrity of astronauts, experiments are regularly carried out to test various antibacterial and antiviral approaches.
Boeing, for example, is currently testing a new type of anti-microbial surface coating that can prevent the spread of microorganisms. This work could then be used in everyday life, here on Earth, especially in airports.
The experience, in concrete terms, requires residents to regularly touch several sets of objects, including an airplane seat buckle, a piece of seat belt fabric, and a meal tray. Some are treated with the anti-microbial coating, and some are not. As soon as these samples return to Earth, Boeing will analyze the efficiency with which the coating has been able to limit or even stop the spread of microorganisms.
The European Space Agency (ESA) had already carried out similar work recently. The experiment, called Matiss (Microbial Aerosol Tethering on Innovative Surfaces in the International Space Station), returned to Earth earlier this year after more than twelve months in space.