Current Shielding Effectiveness (SE) measurements using the nested chamber method require an electrically large enclosure to ensure predicable field statistics. The main limitation on the enclosure-under-test for this type of measurement is its lowest useable frequency, especially as real world equipment enclosures are reducing in physical size. In this paper, the idea of electrical scalability is investigated, i.e. using a larger enclosure to mimic a smaller one. Results from three electrically scaled aperture dominated enclosures are presented and the relationship between them discussed. The use of Q-factor suggested in earlier work is applied to the three enclosures-under-test and the relationship is examined.