A topic has already been made about this subject, & as “revealed” by it the signals were supposedly a combination of Wheelock MTs & LSMs (or other-candela clear-lens vertical-strobe models), the panel was an ESL 1500-series, & the pull stations might have been ESL-rebranded RSG RMS-1Ts (no one knows about the detectors however aside from them all being heat detectors according to a report). As for how it was activated, that’s something else that supposedly no one knows: it could have been automatically or manually.