Why the Arduino needs RoHS/CE ?

Grumpy_Mike:
No that is the wrong interpretation, RoHS applies to all equipment who's main purpose requires electricity. There are certain exemptions applying to some categories of equipment such as military, medical and building infrastructure. All other categories of equipment on sale in the EU need to be compliment, there is no official logo for this.

CE is required on all goods sold in the EU, it is just a self declaration that the product conforms to all the relevant regulations for that category of equipment. So a CE logo for electronic equipment serves as the RoHS logo as well.

I spent a few years of my life being in charge of regulation at one place I worked for so I have read all the documentation on this and attended training courses on it.

Does not some stuff needs additional (expensive) testing by a notified body, RF devices for instance ?