EMC test for PCB board without housing
ESD tests are best to perform with this housings. 

It is not a good idea to perform ESD tests or surge tests on bare board where the micro controller pins are simply brought out without any protection. Contact discharge tests will fail the boards sooner.

Concerning Arduino boards, each and every pin will fail if we do the tests. 

It depends on the use case of your product.

What is the use case? Is it a medical device? Is it a house hold device, a device just used as rapid prototype only, device meant to be used in lab alone or a device meant to be apart of a bigger subsystem..

If it is latter case, you do not have to be perform ESD tests directly on the board.

Also, for emissions and immunity boards Need no have real RF sections or AC power.. Every trace is there an antenna.  



Concerning Arduino Boards:
I do not expect and also i do not see the industry standards compliance for Arduino (IEC).
Here is the standards they meet. 
https://www.arduino.cc/en/Main/Warranty