In this work we show that, the combination of (i) high mechanical stability (provided by a PS matrix), (ii) high sensitivity and selectivity (provided by a two-dye system of Tris (1,10-phenanthroline)ruthenium(II) chloride hydrate (Ru(phen)(3)) and 7-Methoxy-4-methylcoumarin) and (iii) high reproducibility in the output signal/response, results in a membrane able for monitoring O-2 and temperature in membrane processes at laboratory and industrial scales. Due to the matched sensitivity of the developed ratiometric probe to oxygen and temperature a simple correction algorithm was implemented, which allows at overcoming the vulnerability of the ratiometric signal to the temperature, leading to a robust evaluation of the oxygen concentration. The impact of introducing this photochemical activity in membranes opens a new perspective for non-invasive monitoring of membrane processes (e.g. measurement of temperature in membrane distillation processes, oxygen measurement for monitoring of biofilm onset and development in reverse osmosis). (C) 2016 Elsevier B.V. All rights reserved.