Re: need code referance
Jeff that is not an NEC rule, other than the one required at the furnace.
Here in MA it is a fire regulation and it requires a switch located outside the door of the space the oil fired equipment is located in.
Many times that is outside the door to the basement stairs.
It also has to be clearly identified as the oil burner switch.
If you do not live in MA you will need to ask someone local.