99 ms·

> Glass completely blocks UV-C light. Erm, then why do they come in glass tubes like florescent lights?

• augustt 7y ago
  Not all glass is the same. Pure silica glass will pass UV, the soda-lime glass your windows are made of won't.
• jennyyang 7y ago
  I specifically said UV-C light. Do a bit of research and you'll find the answer.