Figure 6. Units reuse .

Units (triangles) are defined at the lowest level and imported into the models (circles) housing low‐level components so that those components can be reused in other models along with consistent and expected unit information (continuous arrows show unit import directions). Units for higher level modules (‘Calcium_Handling’, in this case) may be (dotted arrows) imported from lower levels or from other ‘child’ models. Additionally, following Principle (8), we include a ‘Units_’ model that houses standard units providing a library of such units for many models to use promoting inter‐model consistency. Higher level constructs can import all units directly from that common source, reducing coupling that the former strategy would incur.