Quantised vortices are created when Hell is expanded from a point close to, but slightly (about 3mK) below, the lambda transition. It is believed that these probably arise through conventional flow processes, caused by non-idealities in the design of the expansion system. Their density is smaller than that of vortices created via the Kibble mechanism in expansions passing through the transition; nonetheless, their presence inevitably reduces the accuracy of the latter experiments for modeling cosmic string creation. An investigation of the phenomenon with improved bolometry, is described and discussed.