Is this double-trapped?

My washer drains into the common 2-inch PVC standpipe that's about 36 inches tall. It bottoms out in a P-trap, then runs about 18 inches horizontally before it enters the main waste stack.
The laundry sink (beside the washer) also has the standard P-trap, but the drain pipe runs three feet horizontally and joins with a waste-T to the washer standpipe about 6 inches above the standpipe P-trap.
Is the laundry sink double-trapped? If so, given that the washer standpipe is its own vent, is this a problem?
--
RDKirk

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RDKirk wrote:

It is double trapping. And the washer standpipe is not it's own vent. The vent must be *downstream* of the trap. (There may well be a proper vent in this situation for the washer trap; we can't tell from here.) Will it all matter? Probably not...
Jim
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Jim is right that it *might* not matter. If it drains smoothly at various volumes of water, then it's not a problem. Often a double trap stops the drainage immediately and you know it.

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