Storage of TVS outside..Good or Bad...or Dangerous???

WTH was that white ''light'' type flash? jeebus

That was the phosphor.

Phosphorescent materials are known for their use in radar screens and glow-in-the-dark toys, whereas fluorescent materials are common in CRT and plasma video display screens, sensors, and white LEDs.
Phosphors are often transition metal compounds or rare earth compounds of various types.

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