During my time with my previous employer I was contacted by a company called Samotics who use MCSA to offer a condition monitoring solution called SAM4 Health. If you check out the resources section of their website you may find some information useful. It's an interesting concept, but my initial gut instinct feeling is that it would only be beneficial as part of a system containing a broader spectrum of methodologies rather than a stand alone solution in itself. The biggest advantage for it however, is that it reduces the need for adding sensors in hazardous and hard to reach areas, making the implementation process a lot easier and potentially cheaper, never mind the HSE benefits. Unfortunately, my previous employer had, by the time Samotics had contacted me, already decided on another more traditional approach (vibration sensors and Senseye). 

Good luck with your research. I look forward to you sharing with us what you find out.

Richard.