The Impurity Study Experiment (ISX-B) data base from which the energy confinement time scaling was derived for neutral-beam-heated discharges has been enlarged. Results obtained by using a non-gettered vacuum vessel and different minor and major radii are now included. Energy confinement times improve and a density dependence is introduced, if gettering is not employed. There is an associated increase in impurity radiation. A comparison of confinement properties obtained by using two minor radii (∼ 19 cm and the usual ∼ 26 cm) has been made. The correlation between radiation level and confinement is always found. No dependence of energy confinement on the minor radius is found. The confinement changes associated with wall conditions and radiation levels can be reproduced by using a gettered vessel and small plasma position displacements. In particular, outward radial displacements toward a limiter at the outer equator improve confinement. In this case, any radiation increase is small.