Travel is one of the main ways that any form of the disease is transported between people, across regions and borders but it is also, an effective transport network is fundamental to the economic well-being of a nation. It must continue to function safely, with the minimum of disruption. In order to resume this key role, transport settings must adapt to become not just more Covid-secure but become Pandemic Resilient, ready for the long-term and whatever pathogens may come in years ahead. The main threats are airborne respiratory illnesses.
Specific risks in the transport industry
Even before the COVID-19 pandemic, public transport was conducive for microbial transmission due to a range of factors:
Many people from a wide range of geographical areas being in close contact with one another for sometimes prolonged periods of time.
Many transport services do not have reliable ventilation to clean the air from any hazardous pathogens.
Certain types of transport have been identified as a particularly high-risk setting for the transmission of airborne pathogens, such as shipping or cruise ships, some types of older trains and buses with no windows. In contrast, modern trains and planes are very good in bio-protection with adequate ventilation rates and excellent filter systems suchas HEPA Filters. Some aircraft and trains also have UV devices fitted in the ventilation systems with the former. (This is the ideal specification)
However, when people enter the buildings to queue or wait within interior settings at either end of the journey, these are the spaces most likely to pose a greater risk than the mode of transport itself.
Transport often necessitates handling surfaces such as doors, grab bars and handles, seats, buttons and more.
Due to having been designed prior to the COVID-19 pandemic, some types of interior spaces in public transport may actually accelerate infection because of their ventilation arrangements. Features which may exacerbate this include the use of recirculated air/ceiling cassette systems or floor heating grill systems.
How to achieve better internal air quality
We must focus on improving internal air quality to protect our transport networks for the long-term and do so whilst protecting against any respiratory threat, whether that be airborne viruses, bacteria, spores or pollutant particulate matter.
Interior environments now will need to reassess potential:
· Ventilation airflow rate rates
· Ventilation methodology (avoiding recirculated air systems, fan coil units, e.t.c.)
· Ventilation system filters
· Directional air flows
· Supply of clean, uncontaminated air
· Zoning of air systems in the terminal buildings and within the modes of transport
· Staff and passenger exposure to bio-aerosols pathways and interventions.
· Small rooms, awkward space configurations and dead air zones.
· Queue times and spaces with long dwell times.
· Periods and spaces of overcrowding and queuing
· Local Air Pollution Index and nature of local pollutant matter.
By coupling decent filters with UV-C technology and retrofitting them in-duct in HVAC systems, these systems would be able to provide fast and efficient air disinfection, allowing people to breath cleaner, disinfected air which will help to significantly reduce the risk of transmission. Retrofitting HEPA Filters into HVAC systems is mostly a non-starter because of the pressure drop and significant drop in air change rates.
Engineering improvements to air ventilation systems, especially with UV-C interventions, may be a vital step to restoring safer, more pandemic resilient transport and terminal buildings, increasing passenger confidence whilst also hitting low carbon targets.
As professional engineers, scientists and medics, we intimately know how to target the infection risks by designing targeted solutions, combining established engineering excellence with validated, proven health technologies to take your biosafety across your asset base to a new level and for the long term.
Our solutions have been proven over decades in high-risk applications against other microbial hazards. Our products have 80 years of infection intervention deployment and uniquely helped reduce coronavirus infections in Singapore and Hong Kong hospitals and other essential buildings during the first SARS (Covid) pandemic in 2003.