I am installing a King Brand PAW model 240 volt forced air heater in my bathroom. King manual only requires 6inch from adjacent wall. See attached link-
http://www.king-electric.com/prodtemp.asp?prodID=HEAT_PAW_DEC_SL_INFO
I am installing on dedicated 20amp 240 volt dedicated circuit with switch on other side of shower.
Does NEC say anything regarding heater distance from shower door?
Thanks.

No, just follow manufacturers instructions and common sense.

Location of the switch is paramount. You do not want someone who is in the shower to be able to reach and operate the switch while in the shower.

This could lead to a fatal shock to the person in the shower.

I know what is safe- but want to know if NEC comments anywhere regarding appliance distance from shower, heater locations in bathroom?

I answered this question, No, there is no NEC requirements just follow manufacturers instructions.

Location of the switch is paramount. You do not want someone who is in the shower to be able to reach and operate the switch while in the shower.

This could lead to a fatal shock to the person in the shower.According to the NEC the switch can still be directly adjacent to the shower. Do you think this would have stayed in the code if there were any safety issues?

Can you explain how this fatal shock will occur if the switch is wires and installed properly?

Thanks! I will have my rough-in inspection from local government- let you know the results later.

Got my rough-in inspection! No questions at all regarding the heater! Thanks for your help.