The aim of this project is to provide healthcare workers with a reliable method of protection against aerosols which can contain the new coronavirus particles.
We based our project on existing devices, and tried to find a parts which are widely available. For this we used a online store with shipping in a wide part of the EU, with parts that can also be easily ordered from China in bulk at even cheaper prices.
The case can be 3d printed on most standard size printers with a maximum dimension of 200 x 140 mm print area.
The filtering material used is either custom made, medical grade ULPA class U15 filter (with filtration level of 99,9995 of particles of particles over 0,10 µm) or HEPA class H14 (with filtration level of 99,995 of particles of particles over 0,15 µm). For pre-filter we use G4 filtering class material.
The ventilator used is a more powerful 12V blower fan which at a idle voltage of 6V provides enough flow and pressure for a accelerated breathing rhythm.
The PAPR uses a 2 battery Li-ion system which provides a tested autonomy of over 8 hours on a 6V consumption.
The general list of components is: • 3d printed PLA case • 12V 42W blower fan • 2 x 3.7 11Ah Li-ion batteries • 1 step-up converter from 3.7V to 5.5 – 7 V (power to the fan) • 1 battery indicator • 1 On/Off switch • 1 potentiometer for voltage adjustment (to increase/decrease flow/pressure of device) • 1 C14 charging port with 500a fuse • 1 Schottky diode • 1 AC to DC converter • 1 step-down converter (for charging of batteries) • Custom made ULPA/HEPA filter
Total price of the parts for RON 700 (aprox. 140 $) for the device. This can be printed with a outlet for existing hoods or one can be made from scratch for around 30 $.
Production time of this device is of aprox. 48 hours (for printing the case). Assembly time is 2 hours.