There is another issue relating to the behind-screen vortex.

We had to go through the San Gotthard tunnel two years ago when the northbound side was closed and all traffic was in the one tunnel with a lane in either direction. After that experience I vowed never to do it again without a medical mask. The whole inside of the car was covered in a fine dust that was full of fine carbon, metal powder, and who knows what else. I can only imagine what finished up in our lungs.

Peter

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