I have a good grounding, but I would still consider myself to be a novice!!!! I am in the process of adding an Extractor Fan to the lighting circuit in the bathroom. The lighting wiring is modern and consits of a brown, blue and naked earth. Can I add the extracter fan to this by adding in the corrosponding brown and blue from the lighting to the fan? There is a permanant live which needs to be added as it is a timer fan. The fan has a Live, Neutral, Permanant Live. Is there anything else I would need to consider?