The use of level sensing has allowed cylinder changes to be accurately predicted and has enabled greater streamlining of production processes. Level sensors are particularly important for larger cylinders (>1L) and for liquid dopant sources. Therefore, having a level sensor can reduce the risk of depleting the source material during a growth run. As such, Akzo Nobel HPMO now offers level sensing for its liquid sources. Level Sensors can be accommodated on any cylinder that has a volume greater than or equal to 600 mL. The cylinder design must have a “fill port” which is used for mounting the sensor. The most common Akzo Nobel Level Sensors in use are on our 600 mL, 1L, 3L, and 8L bubblers.