In-Rack Sprinkler Control Valve for Pre-Action?

​In-Rack Sprinkler System Control Valve Arrangement:

Concerning the valve arrangement shown in Figure 7.8.2.8.4 (NFPA 13 - 2016): (One preaction valve is used for both ceiling and in-rack sprinklers protecting the same area)

In-Rack Sprinkler System Control Valves section in NFPA 13 requires that separate indicating control valves and drains shall be provided and arranged so that ceiling and in-rack sprinkler systems can be controlled independently.

Assuming separate detection systems for ceiling sprinkler systems and in-rack sprinkler systems:
Is the separate check valve in the Figure 7.8.2.8.4 for ceiling & in-rack required for a single interlock preaction system? Could it be removed?

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