Hi there,
This is Bogdan from Romania.
I'm a mechanical engineer - specialized in the industrial robotic field, 3D designer and modeler (from time to time and some projects I could make the functional prototype too).
I'm doing product design, industrial design, reverse engineering, ideation, etc.
I have over 15 years experience working on various systems/devices across multiple industries, from concept to launch.
1 - the basin needs to be dried or emptied?... is a huge difference... (in any basin, when getting out the fluid inside, will remain some on the bottom and also on walls...)
2 - it is important the upper level of the basin, or this issue is covered with other installation?...
3 - in my vision, in order to have the proper signal when the basin gets empty, due to the specific nature of the environment (explosive vapors) the best solution would be a floating body, which to slide inside a hollow tube and to trigger a hall relay (no sparks) which to send the signal/command to a lighting alarm, or in a more elaborated configuration to another mean of signaling
4 - the said solution, could be easily implemented onto any existing basin, without any special preparation - the only "sensitive" matters being the way to attach the device to the inner wall of the basin, and the proper protection of the cable
Regards
Bogdan