Implicit in the flowline concept is the standardisation of product design. In a volume manufacture situation, a small reactor vendor will not be able to cope with customisation demands without destroying the economic model for the sector. The design will therefore be fed through a sealed manufacturing route. In itself this is no different from many other high-quality, assured manufacturing operations but it raises questions such as the regulator’s approach to manufacture of components that could be fitted into any one of a number of reactors going through the flowline at that point. Although this issue could be seen as implicit in the NRC’s Part 52 licensing regime, it is not obvious that implications such as this have actually been considered in the detail required.