Making PUBLIC Transport safeR in times of covid-19

INTRODUCTION

Since the COVID pandemic is not over, alternative and innovative methods of Virus management have been implemented in public transport. In this article, we will focus on the following techniques:

• Copper
• High Efficiency Particulate Air (HEPA) filters

THE COPPER

Copper alloy ions are both antiviral and antibacterial, capable of killing more than 99.9% of bacteria within two hours. Copper is even more effective than silver, which requires moisture to activate its antimicrobial properties.

MILAN LINATE airport

In an attempt to combat Covid, S.E.A. (Società Esercizi Aeroportuali) is carrying out a pilot project to use a line of antiviral copper coatings known for their antiviral and antibacterial properties.

All the surfaces that are most in contact with passengers – handrails, luggage trolley handles and supports in the Cobus – will therefore be coated with copper.

The Institute of Virology of the University of Pisa has demonstrated that in 60 minutes the viral load of the Sars Cov-2 virus is 100% neutralized and that in just 10 minutes it is already reduced by 90%. (F1)

THREE LESSONS FROM CHILE

Copper is a “super material’ with antimicrobial traits.

Chile is one of the world’s largest producers of copper and is using this material to help its country prosper and the world tackle COVID.

The country’s use of the material could change the way countries use their natural resources to drive innovation and progress. (F2)

HEPA FILTER

The term HEPA stands for High Efficiency Particulate Air. It is physically a mechanical filter capable of screening out small particles at a much higher rate than any other conventional filter.

The Most Penetrating Particle Size (MPPS) for each filter is in the range of 0.12 to 0.25 microns. Coronaviruses are larger viruses. Their size is estimated to be between 0.12 and 0.16 microns. Fortunately, viruses do not move independently and usually bind to other types of particles (especially aqueous ones), including respiratory droplets, which are the main mechanism of human-to-human transmission as described in the World Health Organisation (WHO) document.

These respiratory particles are larger than 5 microns. So you can see that in this case the size is well above the minimum size filtered by a HEPA filter (0.12 to 0.25 microns) and this is where HEPA filters really do their job: they trap the respiratory infection droplets (or other particles) to which the viruses have attached themselves and prevent them from remaining in the cabin, whether in an aircraft, a bedroom, a house or a public toilet (F3).

The actual use of HEPA filter can be summarized by these list

CONCLUSIONS

Finally, we need to know what percentage of particles the HEPA filter is able to block and what percentage of particles pass through it. Keep in mind that 100% filtration is impossible, but these types of filters are quite close to MPPS. Using HEPA filter together with copper ion enables high efficiency disinfection.

BIBLIOGRAPHY

(s.d.). https://www.milanomalpensa-airport.com/en/passenger-guide/news/linate-touchless

(s.d.). https://www.weforum.org/agenda/2020/08/could-copper-beat-covid-19-three-lessons-from-chile/

(s.d.). https://www.mediclinics.com/en/blog/23_are-HEPA-filters-a-safe-solution-for-covid-19.html