Shelter fan works on 2 different sides.
Normally, fresh air is sent from G-4 panel filter to shelter. In Other exceptional circumstances and on times, fresh air is passed through nuclear, biological, chemical gases, activated carbon filter, hepa filter and lead aliminator.
Fans used in devices are choosen for backward curved blade.
Dampers that are on the device are important for according to usage.
There is an explanation:
Shelter Fan’s emergency dampers and normal time dampers, related blades are opened for which position of device is required to work and other dampers’ blades pass turn off position. In this way, special filters are not used on their normal time. Fans are selected and designed by considering with maximum efficiency and optimisation.
It should not be forgetten, filters that into the device and have shelf life should be changed from time to time. We can list these filters: G4 panel filter, Activated Carbon Filter, radioactive nuclear fall-trap filter and lead separator. Fresh air is first filtered through the G-4 container, then filtered through activated carbon so that the hepa filter of Nuclear Type H-13 can last for a long time. The fresh air is finally supplied to the shelter site after being passed through the lead eliminator to remove the Nuclear type Hepa filter and harmful X-rays.