Homemade Gas Mask/Respirator attempt

DIY attempt to make a homemade gas mask that is capable of taking 40mm filters, to do this I used a plastic shopping bag, cut a hole in it to take a 40mm Soviet hose, then taped the hose into place on both the inside and outside of the bag, I then cut an eye slit and used clear sellotape on both sides to make it air-tight and transparent, lastly the bag must be tied around the neck.

If you attempt to make your own homemade gas mask be very careful, it would be easy to suffocate yourself with a plastic bag and without a working exhale valve, carbon dioxide can build up inside the bag.

Obviously this is a very simple design and you could make something far better with more time and resources, but it is a proof of concept you can make a gas mask from a plastic shopping bag.
However you can buy 3M disposable ABEK masks or surplus gas masks very cheaply, something like this is quite redundant.