diff --git a/src/newgrf_roadstop.cpp b/src/newgrf_roadstop.cpp
--- a/src/newgrf_roadstop.cpp
+++ b/src/newgrf_roadstop.cpp
@@ -346,7 +346,7 @@ void TriggerRoadStopAnimation(BaseStatio
 		const RoadStopSpec *ss = GetRoadStopSpec(cur_tile);
 		if (ss != nullptr && HasBit(ss->animation.triggers, trigger)) {
 			CargoID cargo;
-			if (cargo_type == CT_INVALID) {
+			if (!IsValidCargoID(cargo_type)) {
 				cargo = CT_INVALID;
 			} else {
 				cargo = ss->grf_prop.grffile->cargo_map[cargo_type];
@@ -379,7 +379,7 @@ void TriggerRoadStopRandomisation(Statio
 	/* Check the cached cargo trigger bitmask to see if we need
 	 * to bother with any further processing. */
 	if (st->cached_roadstop_cargo_triggers == 0) return;
-	if (cargo_type != CT_INVALID && !HasBit(st->cached_roadstop_cargo_triggers, cargo_type)) return;
+	if (IsValidCargoID(cargo_type) && !HasBit(st->cached_roadstop_cargo_triggers, cargo_type)) return;
 
 	SetBit(st->waiting_triggers, trigger);
 
@@ -406,7 +406,7 @@ void TriggerRoadStopRandomisation(Statio
 			if ((ss->cargo_triggers & ~empty_mask) != 0) return;
 		}
 
-		if (cargo_type == CT_INVALID || HasBit(ss->cargo_triggers, cargo_type)) {
+		if (!IsValidCargoID(cargo_type) || HasBit(ss->cargo_triggers, cargo_type)) {
 			RoadStopResolverObject object(ss, st, cur_tile, INVALID_ROADTYPE, GetStationType(cur_tile), GetStationGfx(cur_tile));
 			object.waiting_triggers = st->waiting_triggers;