A2L with multiple systems

EN 378 has maximum refrigerant charges for A2L refrigerants per room area but is this per system or can two split systems be installed in the same room? It seems to make sense that only one system is likely to lose its refrigerant at any one time. I can't find anywhere that states this can't be done.
Anyone else know?

The safe calculation refers to how much refrigerant will be discharged into the room in the event of a leak so as to displace the oxygen. If you have 2 systems in the room then you have to add both gas charges together as they could potentially leak at the same time