"joe" wrote in message
.. .
blueman wrote:
Is it allowed to run both 110v wire (either THHN or Romex) and low
voltage alarm wire (e.g., 4 conductor 22 gauge) in the same 1/2" rigid
metal conduit?

I probably will have one 2-conductor #14 Romex wire for overhead
garage light plus a couple of alarm cables for the window, door, and
heat sensors.

Thanks
I think the insulation on the low voltage has to be rated to insulate
the highest voltage in order to do what you want to do.

Right on.

You will pay dearly for that stuff rated at 300 volts. Available, even at
600 volt insulation

By the way romex typically is not rated to be in conduit.