FSoE CRC: Which polynomial does it use?

Failsafe over EtherCAT (FSoE) uses a CRC-16 polynomial for error detection. The specific polynomial used in FSoE is:

0x139B7

which is called the Safety polynomial.

Source: ETG.5100 S (D) V1.2.0, section 8.1.3.2: CRC polynomial selection, available on request from the EtherCAT Technology Group (ETG)