it's not conduit in that case, it's a sleeve.

I believe the issue is 'future identification'.
Imagine your surprise if you were working at an
unfamiliar site and opened up a wall with a piece
of plumbing PVC in it and you had to remove that
'pipe'. So you get out your saw and start cutting
away, unaware there are power cables inside. I
would hope you weren't well grounded.

ibpod does have a point, but look at my thread about tr recs. they are way more dangerous than standard recs, in my point of view, but they are REQUIRED. the code writers are idiots, at best. i beleive 15a circuts should be illegal.

An interesting suggestion, but I have any issue with people who cut through parts of ANY mechanical system (plumbing included) without knowing what it is beforehand.

15A circuits are fine for permanently-installed lighting and certain dedicated circuits.

I have two 15A circuits running all of the lights in my current project - one for the basement and one for the main house. There are 3-ways and fan/light combos with seperate switching, and a 4-way. Interconnected hardwired smoke detectors are on this circuit as well. A diagram looks more like a schematic for an amplifier or something. Just the same, everything is neat and not overcrowded. If I had to implement it all with 12awg I'd kill myself.

At the same time, there is not a single duplex receptacle in the entire house that isn't on a 20A circuit.

I'd be really hesitant to use PVC pipe in place of conduit, even in a situation like this. It just about screams "this work was done by a non-professional," and you never know who might hear that message in the future.

That in fact is exactly what I thought several years ago when I dug up some buried NM (not UF!) on my property. I knew it was a hack job even before I saw the NM, because it had been run in a length of flexible polyethylene water pipe.

k27k's neighbor has some romex running in a garden hose. it feed a dusk to dawn lamp.

i rewired my boiler with 12awg mc. the #$$%% plumbers wired it with romex that had a 60c/140f jacket on 190f pipes! they also too the ground and wrapped it around the jacket, i could see on the fused disconnect box that there had been arching due to the loose locknut.

An interesting suggestion, but I have any issue with people who cut through parts of ANY mechanical system (plumbing included) without knowing what it is beforehand.

I understand what you're saying, why not add a little extra physical protection, even if it's not required, in case someone gets overzealous setting their tulip bulbs. I think though that if someone comes across a length of DWV pipe they should reasonably expect to find air or sewage.

Imagine a few years go by and there's a new owner. He's digging and comes across this piece of PVC. Maybe his first thought is that the previous owner roughed in for a slop sink in his garage workshop. Right, wrong, or indifferent he doesn't investigate further and has at the pipe with a Sawzall.

To some degree the code protects people from themselves. Who in their right mind would use a hair dyer in the tub but they do and now we have GFIs on the end of hair dryer cords. I think professional have some obligation to do a little forward thinking in that regard. I've never been a big fan of MWBCs in residential construction because people don't understand them. Now I understand that the breakers are supposed to be tied but I've see enough that aren't and that can be a little dangerous.

... the handles need to be tied if the two circuits end on the same yoke. afaik, it isn't YET required that they be tied otherwise.

I've got one MWBC in my project that doesn't have tied handles. Two circuits ran by "the last guy" magically got shorter when the wires were re-routed, I needed to extend them both about 3 feet, had a long enough scrap of 12/3 (actually 10/3) on the floor in front of me, and extended both circuits with the one cable. They're joined for a 3-foot run and seperate as soon as they hit a junction box on the ceiling above the panel (which is in its own little closet that will never receive a finished ceiling). Otherwise I would have done something about tying the handles.

Pipe... well the cable to the garage finally got buried today, it is not in pipe, but does have some heavy plastic grating laid down about 6" above it. No idea what this stuff is meant for but it should definitely deter anyone digging there.

Of course, since it's literally less than a 5-foot span, and one can see the LBs on both ends simultaneously, and the wire runs in a straight line otherwise... anyone digging in that spot, without being able to figure out that there's a high likelihood of a wire there, is a moron anyway.

There are phone, data, and coax next to it, Those ARE in a pipe, it's some sort of semi-flexible black stuff originally affiliated with the now-nonexistant swimming pool.

"... the handles need to be tied if the two circuits end on the same yoke. afaik, it isn't YET required that they be tied otherwise. "

The newest NEC requires them to be tied period.

It may not have been adopted yet in many places, so ask the AHJ what code revision they are using.