Network Rail in the UK has many rather scary safety videos.<p>Here's one that's relevant to the SF bay area.[1] It's about the dangers of aluminum Mylar helium balloons near overhead wire. Those balloons are conductors, and so are their shiny metallized ribbons. If one of those things gets close to high voltage overhead wire, the holder will be electrocuted. In wet weather, ordinary non-metallic strings become conductive. Network Rail has deaths this way regularly.<p>The SF bay area now needs that warning. CALTRAIN electrification is close to power-up. That's expected in Q4 2023.[2] This is the first time the SF Bay Area has had 25KV overhead wire close to ground level. (SF Muni is 600VDC. BART is 1000VDC. Most power transmission lines at higher voltages are much higher up than railroad power. Caltrain wire is at roughly 5 meters.)<p>Balloons on long strings are now deadly near the tracks. Tell people this.<p>[1] <a href="https://www.youtube.com/watch?v=udaS3NDCkk0">https://www.youtube.com/watch?v=udaS3NDCkk0</a><p>[2] <a href="https://www.caltrain.com/projects/electrification/construction" rel="nofollow noreferrer">https://www.caltrain.com/projects/electrification/constructi...</a>