There's no direct equivalent between a BA degree and an NVQ level. The frameworks are structured differently and assess different things. NVQs (National Vocational Qualifications, now largely replaced by RQF qualifications in England, Wales and Northern Ireland) focus on occupational skills and competencies demonstrated in a workplace setting. A BA (Bachelor of Arts) degree focuses on academic learning and theoretical knowledge within a specific subject area.
While a BA degree holder might *possess* skills that could be assessed at a high NVQ level (perhaps equivalent to Level 6 or 7 in the RQF, depending on the specific BA and the NVQ in question), there isn't a formal, nationally recognized conversion or equivalence.