this is a tough one, what about smaller pieces and have the performers do glow tape practice. anything for marking seen in the dark can illuminate and be seen.
If anything applied to the floor with depth will create a trip hazard.
Possibly cardboard box(like a Christmas shirt box, cut a side bottom very low profile to hide from the audience) with glow tape on the stage facing L , that way if stepped on would not trip.
Creative set design to use the back of scenery/set pieces with glow tape on them.
Night vision to get to place then take off and hide
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Jerry Onik
V.P. Theatrical Supplies and Equipment
Heartland Scenic Studio
NE
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