Mil-std-6040b
If you are under a DoD contract, your Program Office HSI lead must approve your compliance strategy. For non-DoD applications, the standard remains best practice for high-reliability human-machine systems (e.g., nuclear, aerospace, medical).
MIL-STD-6040B integrates HFE earlier into the acquisition lifecycle (pre-Systems Requirements Review) and adds greater emphasis on human-system integration (HSI). mil-std-6040b