Index: firmware/App/Controllers/SyringePump.c
===================================================================
diff -u -rec4abf209e338090e861defd54e38b692d85e2b1 -reb8477e165e028478922b8c7dd9bdd2564b90525
--- firmware/App/Controllers/SyringePump.c	(.../SyringePump.c)	(revision ec4abf209e338090e861defd54e38b692d85e2b1)
+++ firmware/App/Controllers/SyringePump.c	(.../SyringePump.c)	(revision eb8477e165e028478922b8c7dd9bdd2564b90525)
@@ -1113,6 +1113,7 @@
     syringePumpPosition.data = encPosition - syringePumpHomePositionOffset;
     // Calculate volume delivered from position
     syringePumpVolumeDelivered.data = (F32)( syringePumpPosition.data - syringePumpVolumeStartPosition ) / SYRINGE_ENCODER_COUNTS_PER_ML;
+    syringePumpVolumeDelivered.data = MAX( syringePumpVolumeDelivered.data, 0.0F );
     calcSafetyVolumeDelivered();
     // Calculate measured rate (mL/hr)
     calcMeasRate();