is there a standard depth for house slabs

Another thing to consider is if building in an area with soil subsidence issues like they have in parts of N.O. East and Kenner is to run hanging straps around the plumbing drain lines and allow the ends to be incorporated into the slab.

After pilings are driven, pipes are laid and the slab poured, after a while there could be subsidence that allows unstrapped pipes to sag and break.

He asked about pilings the other day. More than likely if there are pilings, I'd bet the pipes under the slab should have stainless steel hangers.

I'm using pipes as a general term for plumbing, electrical, and anything else.

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That said, I don't want to go drilling concrete anchors in the slab and bust a pipe.

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This may be asking a lot of your slab guys, but if you have the safe and can get a pattern for the bolts needed to secure it to the slab, have them place them in the wet concrete when the slab is poured. That way they will be well incorporated in the concrete and offer the best hold, especially if the bolt heads are in the slab with just the threaded part above it.

If that is not an option and you have to do it yourself, drill about 3 inches into the slab and secure the threaded rods with epoxy to secure them or use some type heavy duty anchoring system. But definitely find out where your plumbing is before drilling just to be safe---pardon the pun.

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I don't want to go drilling concrete anchors in the slab and bust a pipe

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Typically no plumbing should be in the slab, should be underground. Electrical conduit is probably run just under the slab if any. You should be fine, just dont drill through the entire slab.

you should be fine. plumbing waste drain lines are not supposed to be in the general run of the slab (top 3.5" - 4").
to be extra careful, make sure you don't drill next to a known plumbing wall. a plumbing wall will either be 6" thick or have some type water service sticking out of it.

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I have no idea if its post tensioned.

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Does your slab edge have little round pockets that have been grouted in like the pic below?



If so, it’s post tension and I would be cautious drilling into the slab.

If not you should be OK drilling in some expansion anchors with 3” of embedment into the slab.

The tendons snap and will likely blow out the concrete.

ETA:

They make rebar scanners similar to stud finders. They usually start at a few hundred but it might be something a rental place carries.

Makes sense.

I've only dealt with it in commercial applications and it can be pretty catastrophic.

Ya, we worked in a building where one snapped. From what I was told this cable broke a bunch of concrete and flew out of the side of the building. Luckily, no one was hurt.