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There are umbrellas available which have a non-conducting handle and bar, e.g. made from graphite (example product, german website). If I'm walking around with this umbrella in a thunderstorm (not on purpose, of course):

  • Will my chances of getting hit by lightning be lower compared to using a regular umbrella?
  • Will my chances of getting hit by lightning be lower compared to not using an umbrella at all?
  • If the umbrella is hit by lightning, will I be hurt?
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  • $\begingroup$ graphite can be a good conductor in some directions. If I recall correctly, the resistivity of bulk graphite is anisotropic. $\endgroup$ – G. Bergeron Dec 9 '16 at 10:30
  • $\begingroup$ On the website, they state that the material being used is graphite. You're right about the anisotropy. Probably they build the umbrella in a way that the non-conducting direction is the direction of the pole. $\endgroup$ – Timitry Dec 9 '16 at 11:06
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First, graphite is a conductor. It is used in the umbrella because it is a strong material that resists bending. Second, a lightning strike makes everything a conductor, including people and trees.

In order:

  • No. The primary target of lightning is the tallest object in the vicinity. Trees are very commonly struck, despite being non-conductive.
  • There is possibly a slightly greater chance of being hit with an umbrella versus not having one due to the height difference. The greater danger is the umbrella slowing down you running for shelter.
  • If you are holding it, yes, no matter what the umbrella is made of. Millions of volts make everything a conductor.

To stay safe in a thunderstorm consult here: http://www.lightningsafety.noaa.gov/tips.shtml

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  • $\begingroup$ As discussed in the question's comments, graphite only conducts (good) in one plane. However, the material is not so important, let's just say it's any insulator. Guess you're right about everything being a conductor regarding really high voltages, though :) $\endgroup$ – Timitry Dec 9 '16 at 11:08

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