Cooling fan blade snapped off

[blink_willie]

I run a cooling fan 24/7 and yesterday night I discovered that it was very noisy and vibrating a lot.Switched it off to discover that part of the blade had snapped off.

Anyone encountered this before?I am curious as to what caused it...

[Fuzzy]

I work in the IT line and deal with many many fans of this type.

Sometimes its wear and tear, but very unlikely, even in 5+ year old fans. even if its in direct sunlight and becomes brittle.

The only way I've broken fans is by sticking my finger into it accidentally..ouch.

Aside from that maybe a gecko dropping into it, or a large moth flying in might have done it. Higher RPM fans can snap blades much more easily.