On Sunday, June 12, 2016 at 11:57:55 AM UTC-4, net cop wrote:
Pat Dixon writes:

How long can kitchen garbage disposals things run dry?
Are they ALWAYS supposed to have water every second they're running?

They are neither cooled nor lubricated by water.
Running dry only wastes electricity.

--
Dan Espen

I agree, probably true indefinitely, but certainly true for any
occasional running for 30 secs or whatever. Unless of course
you're feeding it stuff at the same time, in which case you'll
clog the pipes. THAT is probably the reason for the caution
about always having the water running.