For traceability you would need to look at Do-178C. I am currently not aware that ISO 61508 (general functional safety) and ISO 26262 (automotive functional safety) require traceability between source code and executable machine code.
All standards specify different levels of safety. Lower levels come with fewer requirements and are easier to implement, but are recognized as less reliable and therefore limited to less critical applications.
All standards specify different levels of safety. Lower levels come with fewer requirements and are easier to implement, but are recognized as less reliable and therefore limited to less critical applications.