There’re plenty of applications for using fiber optics sensors in the industry.
In the DWDM world, installing fiber sense system on a working optical cable may give you the needed information when there’s civil works on-going near your cable, maintenance in a shaft/volt, and tell you where exactly this is happening.
The three most advanced solutions (in my short research) are:
1. https://fibersense.com/
2. https://www.apsensing.com/
3. https://senstar.com/
These companies cover utilities monitoring, submarine applications, oil & gas, railways, seismic monitoring, etc.