What is the industry standard for galvanic isolation? How to provide galvanic isolation?

 

I'm not sure there is a standard. Most of the standards I've ever encountered were nearly useless from a practical point of view.
The following article may provide some insight and references for you.
http://en.wikipedia.org/wiki/Galvanic_isolation

 

I imagine it will vary to some extend as to the voltage level and the environment you are working in?
Max.

 

A standard component to achieve galvanic isolation is of course the good ole dual winding transformer.

 

And the ever popular optoisolator, where information travels on small beams of light.

 

There is no standard. It's however much isolation the particular application requires.
Common methods for galvanic isolation are transformers and capacitors for AC signals.
Electromagnetic waves can also be used for isolation such a opto isolators or other RF transmitters and receivers.