Hi,
Well, there is no eligibility criteria nor any central certifying body for Lean Six Sigma. Speaking about course duration: there are multiple levels in LSS: White belt, Yellow, Green, Black, Master Black belt. White and Yellow have almost become obsolete now and you can directly start from Green Belt and then move on to Black Belt.
However, I would suggest you make sure you need a Black belt before you opt for it. For most LSS GB and a PMP certification is more productive. If you are taking up a Green belt certification Course, it should typically be of 4 days and you might require another 15 days (being a little lenient on the days) to clear the examination. Same holds true for the Black belt. However, you might have to spend a little more time on the Black Belt. As there is no central certifying body, your training company will issue an in-house certification in maximum case.
Hope this helps.
Good luck.
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