A320 :APU start during refuelling
In my airline APU start during refueling is not allowed . The reason : a very vague explanation is given in OMB , regarding the fuel track being too close to the APU , alluding to possible fuel vapor from the track being ignited during APU start .
AIRBUS itself does not have such restriction . The only concern for Airbus on this matter , is a potential electrical transient of the APU gen (APU gen taking over from the external power ) which could stop the automatic refuel process .
I'd like to know how other operators handle such issue and what restrictions if any you may have .
Thank you