When sealing a mining truck cabin with the intent of pressurization, CO2 levels can increase to dangerous levels in less than an hour, putting drivers, cabin occupants and mine workers at risk of causing fatigue, which has the potential of causing collision and workplace accidents.
Common practice in mines can be to place OEM air conditioning systems into recirculation mode to minimize dust ingress but this can result in sharp CO2 rises to unsafe levels. Likewise, alternate aftermarket pressurizer systems can do very little in terms of fresh air exchange; some manufacturers require cabs be totally sealed to allow for positive pressure increase. By sealing the cabin completely and adding an occupant exhaling CO2, the CO2 build-up can quickly reach dangerous levels that has an adverse effect on the occupant.
A good comparison in everyday life of over exposure to CO2 is when you’re driving long distances with your family. Have you ever noticed on a long journey that you begin to feel tired while driving? That is because your air conditioning could be on recirculation, preventing fresh air from entering the vehicle. You don’t notice it when it’s just you in the car, but the more occupants in the vehicle, the faster CO2 level rises.
Freudenberg Filtration Technologies has been protecting the health of miners with their S.A.F.E.air cabin protection (filtration and pressurization) systems in mining environments for many years.
S.A.F.E.air positively pressurizes mining vehicle cabins to prevent dust particles from entering. These dust particles could contain mineral fibers like silica and asbestos naturally found in the mining process. The integrated HEPA filters in the S.A.F.E.air unit eliminate these harmful mineral fibers by way of HEPA filtration, filtering out 99.995% of 0.3 micron.
By providing a very high rate of fresh air exchange, Freudenberg S.A.F.E.air systems keep CO2 levels down to ambient/safe levels. It purges old air and replaces it with HEPA clean, fresh air for the cabin occupants.