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I am a member of an amateur high-powered rocketry club at my university, and as a result, I work with motors for these Rockets on a semi-regular basis.
I'm concerned, however, that at some point I'll have to travel following working with these, get pulled over for a random security check, and test positively for explosive residue.
I carry a card identifying me as a member of the national association of rocketry, and would likely have timestamped pictures on my phone of any recent work or launches. Would this be enough to prove that I have been working with explosives for legitimate reasons?