Osisense XU_Reliability data of the XUK9TAH2MM12 laser transmission sensors MTTF?

The reliability data of the XUK9TAH2MM12 laser transmission sensors, used for the anti-collision mode and tandem mode in cranes, are the following :
- MTTF = 213.6 years (mean time to failure),
- MTTFd = 427 years (mean time to dangerous failure),
- DC = 0 (diagnostic coverage) of the sensor alone,
- mission time = 20 years.
They are used for the functional safety of the anticollision function, according to the ISO 13849-1 standard (Performance Level).
The MTTF calculation is made according to the EN/IEC 61709 standard (SN 29500).