As an employer I approve of workers that report on time, dress neatly and bathe regularly, concentrate on getting the job done, and understand that if it was all fun they would have to pay me.
Seriously, "approved" is not a defined term in the sense you are using it. In the USA the ISA (Instrument Society of America) has a "certification" process. Electricians may be licensed by their union or by a local governmental unit. Engineers can be licensed by their state regulatory agencies.
As Jason hints, the best approval comes when you prove you can get the job done. Most of the guys that contribute here have spent five to twenty years up to their arses in bits, bytes, wires, and manufacturer's, manuals. That's what it takes to get peer approval, the hardest and sweetest of all to earn!