Many train passengers are still reluctant to return to public transport with the fear that other passengers may be carrying COVID.

However, Knorr-Bremse subsidiary Merak’s active air purification system has proven to eliminate a range of viruses, including the virus which causes COVID, throughout the train interior using test methods approved by Australia’s Therapeutic Goods Administration (TGA).

Merak has developed and validated an active purification system named Merak Dielectric Barrier Discharge (MDBD) which demonstrates greater than 99.9 per cent effectiveness against airborne viruses throughout the whole passenger area.

In addition, MDBD can eliminate greater than 90 per cent of SARS-CoV-2 and other viruses on surfaces within the train through its ionisation technology. Implementation of this technology will help give reluctant passengers the confidence to come back to public transport and additionally reduce the cost of deep cleaning by operators.

The application can be easily installed within existing air conditioning systems and produces a steady flow of charged particles which are distributed throughout the train interior with the airflow.

These particles attack viruses, bacteria and other contaminants and break them down into harmless by-products. They do this by interrupting the chemical bonds within the pathogen itself, turning these long-chain molecules into mostly water and carbon dioxide.

MDBD’s effectiveness extends to the passenger area, targeting both airborne and surface-borne pathogens, thus significantly minimising the risk of person-to-person transmission during journeys.

The modelling below shows the effect of the MDBD system in preventing pathogen spread from an infected passenger:

In the first picture, the propagation of virus load is shown in an unprotected railcar. Virus loads greater than 500 particles per cubic metre (mid-blue) can lead to infection.

In the second picture, the significant reduction of virus concentration is clear as the MDBD neutralises the virus before it can spread to other passengers.

The performance of the unit has been repeatedly proven in lab testing around the world, including tests in USA, Australia, China, and France, with operators trialling and already using Knorr Bremse’s clean [air] climate control technology. Effectiveness has also been demonstrated in independent testing conducted by the US EPA.

Australia has one of the strictest regulatory environments in the world with the TGA setting guidelines for effectiveness claims.

In line with these guidelines, Knorr Bremse Australia has undertaken the toughest evaluation yet of MDBD technology by testing against the European standard EN17272, which is newly released to specifically validate the effectiveness of purification technologies. This testing confirmed the efficacy of MDBD against the virus that causes COVID.

Merak has a wide range of clean [air] ventilation, filtration and purification technologies that offer comprehensive, adaptable, and scalable protection against the proliferation of airborne pathogens in rail vehicles, and thereby provide health and comfort for passengers all-round.