Static electricity is a plague we try to avid in the darkroom. As an old-time photofinisher, I did all manner of things to alleviate. As you know, film is taped to a plastic spool and or taped to paper backing. When loading film on reels or automated film processor, you are required to detach. Old-timers, like me, will tell you, if you rip when you detach, a static discharge occurs.
If the darkroom has a rug, shuffling your feet will induce a static charge. So will combing your hair. You can experiment, rubbing dissimilar materials together like a glass rod rubbed on a balloon.
Be aware that many things like the above will induce a static charge. To see the discharge, you need to in total darkness and you need to be dark-adapted. Dark adaption typically requires that you remain in total darkness for 15 minutes or more. Also, low humidity enhances the generation of static electricity.
I spent a lot of time trying to prevent, seem weird it’s an art form.