The issue is that water is dripping onto ceiling tiles.
The photograph shows a concrete ceiling embedded with a 3 inch PVC pipe. It would seem that the leak is above the concrete ceiling as the concrete ceiling is wet. Once the leak has been plugged the ceiling tiles will be restored. Approximately 4 ounces of water drips in a 48 hour period.
The blue pan is placed underneath the leak to collect the water.
There are 2 other very similar pipes that pass through the concrete ceiling, which are not leaking. There are two bathrooms in the apartment above and it would not surprise me if these three pipes are drains for either sinks or toilets.
Is there a clever technique that can identify exactly the exact leak of the pipe? Preferably without breaking any concrete.