The Filter Nobody Replaced Sverdlovsk, USSR. April 2, 1979. A technician at Compound 19 pulled a clogged anthrax filter. He left a note for the next shift. The note was never seen. The drying machine ran with no filter. At least 68 people downwind died of inhalation anthrax — the Soviets blamed tainted meat for 13 years.
Source
https://en.wikipedia.org/wiki/Sverdlovsk_anthrax_leakSpot an error? Email hello@thefact5.com with a source — we correct visibly.

