The other technique is denser air filters installed and implemented into the air ventilation system. Air filters are an important aspect of an air filtration system since they clean and purify the air. Efficiency Reporting Value, known as MERVs, is a rating used to determine a filter’s capabilities of capturing and filtering particles of certain microns. The higher the rating, the more efficient the filters are at trapping certain particles. According to the EPA, they indicate that a filter of a rating of 13 or higher on the MERV scale can filter out virus airborne pathogens like COVID-19.
Many public transportations, around the world, have implemented either denser filters or that not only filter airborne contaminants but also destroy them. Train stations like BART upgrade their filters to a MERV-14 and Metrolink to a filter like PuraShield by Purafil. Our team has decided to use a High Energy Particulate Air filter, also known as a HEPA filter, which filters particles in the 0.1-1 microns size range. The reason being these filters surpass many MERV filters in terms of reducing airborne contaminants. The EPA website claims these air filters can remove at least 99.97% or better for all particle sizes. PeruRail is a perfect example of the HEPA filter being implemented and the use of UVC technology. Since the pandemic, PeruRail has introduced HEPA filters into its HVAC system. In an article by PeruRail, PeruRail has claimed to have the most effective air sterilization system. Components of their air sterilization system include a HEPA Filter with Activated Carbon, a Far VC lamp, an Ionizer, and a UVC lamp that guarantees complete sterilization. Figure 3 shows how the PeruRail air sterilization system works, ensuring that the system is 99.9% efficient.
Figure 3: The different phases of PeruRail air sterilization system