diff --git a/src/mol-model-props/computed/accessible-surface-area/shrake-rupley.ts b/src/mol-model-props/computed/accessible-surface-area/shrake-rupley.ts
index d88fb6bccbe0cd2d8f96887677465d9e1c31be5d..80d9c9d22bb62e78d0727f57467a6a0f6dc7702b 100644
--- a/src/mol-model-props/computed/accessible-surface-area/shrake-rupley.ts
+++ b/src/mol-model-props/computed/accessible-surface-area/shrake-rupley.ts
@@ -101,9 +101,8 @@ namespace AccessibleSurfaceArea {
     }
 
     export function getValue(location: StructureElement.Location, accessibleSurfaceArea: AccessibleSurfaceArea) {
-        const { getSerialIndex } = location.structure.root.serialMapping;
         const { area, serialResidueIndex } = accessibleSurfaceArea;
-        const rSI = serialResidueIndex[getSerialIndex(location.unit, location.element)];
+        const rSI = serialResidueIndex[location.element];
         if (rSI === -1) return -1;
         return area[rSI];
     }