Cynic wrote

I was given an iv dose of technecium prior to a bone scan
then sent out for a couple of hours before returning for the
actual scan. I was told not to sit next to babies or small
children for more than a couple of minutes until 24 hours had
elapsed. Maybe I could have tripped a radiation detector?

Yeah, there was one of those on one of those reality TV
series, tripped the meter going thru customs in the US.