Matt,
First, CTs feeding the meters must be in series, not parallel. Then, there's the overall burden on your meters. You need to sum up the overall burdens and cable lead resistances and make sure your CT burden (VA) is sufficient to drive the devices.
Why not just consider installing current limiting fuses?(UL has specified good standards clearing the fault current before half cycle and melting the fuse before even reaching the first peak), then you can do away with the calorie calculations and the hazard labels.