This is a model to allow people to make their wearable HEPA that blows filtered air to their faces, in situations when wearing a respirator is impossible. It's not meant to be a substitute to respirators, but an added safety to the wearer, whether or not a respirator is worn.
This version is the most reliable, in terms of durability and safety. However, if I could find a lightweight power source, this model will be much more compact in both size and weight, which will make the version 5 (the next one) more suitable for kids.
I include both Bambu Labs and Blender files in the archive file.
Additional parts:
The author marked this model as their own original creation.