Can I be tax exempt if I work in Africa and stay abroad during home leave?

If I am a UK citizen (or an Irish citizen for that matter) and work 4 weeks offshore in Nigeria and spend my 4 weeks home leave in Spain am I tax exempt? Or what countries can I live during my home leave in order to be tax exempt? This has caused a multitude of answers and much debate during group pub banter lately. The net is far too ambiguous to give a straight answer. Anyone with knowledge on this subject or who has previous experience please comment.