diff --git a/frontend/app/(main)/COMPANY_10/equipment/info/page.tsx b/frontend/app/(main)/COMPANY_10/equipment/info/page.tsx
index cd53e9b1..f32273ae 100644
--- a/frontend/app/(main)/COMPANY_10/equipment/info/page.tsx
+++ b/frontend/app/(main)/COMPANY_10/equipment/info/page.tsx
@@ -624,8 +624,17 @@ export default function EquipmentInfoPage() {
                       <TableBody>
                         {inspections.map((item) => (
                           <TableRow key={item.id} className="cursor-pointer hover:bg-primary/5" onDoubleClick={() => {
-                            const std = item.standard_value || "";
-                            const tol = item.tolerance || "";
+                            // lower/upper → standard/tolerance 역산
+                            const lower = item.lower_limit !== "" && item.lower_limit != null ? Number(item.lower_limit) : null;
+                            const upper = item.upper_limit !== "" && item.upper_limit != null ? Number(item.upper_limit) : null;
+                            let std = item.standard_value || "";
+                            let tol = item.tolerance || "";
+                            if (lower !== null && upper !== null && !isNaN(lower) && !isNaN(upper)) {
+                              const stdCalc = (lower + upper) / 2;
+                              const tolCalc = (upper - lower) / 2;
+                              std = String(stdCalc);
+                              tol = String(tolCalc);
+                            }
                             setInspectionForm({ ...item, standard_value: std, tolerance: tol });
                             setInspectionEditMode(true);
                             setInspectionModalOpen(true);
diff --git a/frontend/app/(main)/COMPANY_16/equipment/info/page.tsx b/frontend/app/(main)/COMPANY_16/equipment/info/page.tsx
index cd53e9b1..f32273ae 100644
--- a/frontend/app/(main)/COMPANY_16/equipment/info/page.tsx
+++ b/frontend/app/(main)/COMPANY_16/equipment/info/page.tsx
@@ -624,8 +624,17 @@ export default function EquipmentInfoPage() {
                       <TableBody>
                         {inspections.map((item) => (
                           <TableRow key={item.id} className="cursor-pointer hover:bg-primary/5" onDoubleClick={() => {
-                            const std = item.standard_value || "";
-                            const tol = item.tolerance || "";
+                            // lower/upper → standard/tolerance 역산
+                            const lower = item.lower_limit !== "" && item.lower_limit != null ? Number(item.lower_limit) : null;
+                            const upper = item.upper_limit !== "" && item.upper_limit != null ? Number(item.upper_limit) : null;
+                            let std = item.standard_value || "";
+                            let tol = item.tolerance || "";
+                            if (lower !== null && upper !== null && !isNaN(lower) && !isNaN(upper)) {
+                              const stdCalc = (lower + upper) / 2;
+                              const tolCalc = (upper - lower) / 2;
+                              std = String(stdCalc);
+                              tol = String(tolCalc);
+                            }
                             setInspectionForm({ ...item, standard_value: std, tolerance: tol });
                             setInspectionEditMode(true);
                             setInspectionModalOpen(true);
diff --git a/frontend/app/(main)/COMPANY_29/equipment/info/page.tsx b/frontend/app/(main)/COMPANY_29/equipment/info/page.tsx
index cd53e9b1..f32273ae 100644
--- a/frontend/app/(main)/COMPANY_29/equipment/info/page.tsx
+++ b/frontend/app/(main)/COMPANY_29/equipment/info/page.tsx
@@ -624,8 +624,17 @@ export default function EquipmentInfoPage() {
                       <TableBody>
                         {inspections.map((item) => (
                           <TableRow key={item.id} className="cursor-pointer hover:bg-primary/5" onDoubleClick={() => {
-                            const std = item.standard_value || "";
-                            const tol = item.tolerance || "";
+                            // lower/upper → standard/tolerance 역산
+                            const lower = item.lower_limit !== "" && item.lower_limit != null ? Number(item.lower_limit) : null;
+                            const upper = item.upper_limit !== "" && item.upper_limit != null ? Number(item.upper_limit) : null;
+                            let std = item.standard_value || "";
+                            let tol = item.tolerance || "";
+                            if (lower !== null && upper !== null && !isNaN(lower) && !isNaN(upper)) {
+                              const stdCalc = (lower + upper) / 2;
+                              const tolCalc = (upper - lower) / 2;
+                              std = String(stdCalc);
+                              tol = String(tolCalc);
+                            }
                             setInspectionForm({ ...item, standard_value: std, tolerance: tol });
                             setInspectionEditMode(true);
                             setInspectionModalOpen(true);
diff --git a/frontend/app/(main)/COMPANY_30/equipment/info/page.tsx b/frontend/app/(main)/COMPANY_30/equipment/info/page.tsx
index cd53e9b1..f32273ae 100644
--- a/frontend/app/(main)/COMPANY_30/equipment/info/page.tsx
+++ b/frontend/app/(main)/COMPANY_30/equipment/info/page.tsx
@@ -624,8 +624,17 @@ export default function EquipmentInfoPage() {
                       <TableBody>
                         {inspections.map((item) => (
                           <TableRow key={item.id} className="cursor-pointer hover:bg-primary/5" onDoubleClick={() => {
-                            const std = item.standard_value || "";
-                            const tol = item.tolerance || "";
+                            // lower/upper → standard/tolerance 역산
+                            const lower = item.lower_limit !== "" && item.lower_limit != null ? Number(item.lower_limit) : null;
+                            const upper = item.upper_limit !== "" && item.upper_limit != null ? Number(item.upper_limit) : null;
+                            let std = item.standard_value || "";
+                            let tol = item.tolerance || "";
+                            if (lower !== null && upper !== null && !isNaN(lower) && !isNaN(upper)) {
+                              const stdCalc = (lower + upper) / 2;
+                              const tolCalc = (upper - lower) / 2;
+                              std = String(stdCalc);
+                              tol = String(tolCalc);
+                            }
                             setInspectionForm({ ...item, standard_value: std, tolerance: tol });
                             setInspectionEditMode(true);
                             setInspectionModalOpen(true);
diff --git a/frontend/app/(main)/COMPANY_7/equipment/info/page.tsx b/frontend/app/(main)/COMPANY_7/equipment/info/page.tsx
index cd53e9b1..f32273ae 100644
--- a/frontend/app/(main)/COMPANY_7/equipment/info/page.tsx
+++ b/frontend/app/(main)/COMPANY_7/equipment/info/page.tsx
@@ -624,8 +624,17 @@ export default function EquipmentInfoPage() {
                       <TableBody>
                         {inspections.map((item) => (
                           <TableRow key={item.id} className="cursor-pointer hover:bg-primary/5" onDoubleClick={() => {
-                            const std = item.standard_value || "";
-                            const tol = item.tolerance || "";
+                            // lower/upper → standard/tolerance 역산
+                            const lower = item.lower_limit !== "" && item.lower_limit != null ? Number(item.lower_limit) : null;
+                            const upper = item.upper_limit !== "" && item.upper_limit != null ? Number(item.upper_limit) : null;
+                            let std = item.standard_value || "";
+                            let tol = item.tolerance || "";
+                            if (lower !== null && upper !== null && !isNaN(lower) && !isNaN(upper)) {
+                              const stdCalc = (lower + upper) / 2;
+                              const tolCalc = (upper - lower) / 2;
+                              std = String(stdCalc);
+                              tol = String(tolCalc);
+                            }
                             setInspectionForm({ ...item, standard_value: std, tolerance: tol });
                             setInspectionEditMode(true);
                             setInspectionModalOpen(true);
diff --git a/frontend/app/(main)/COMPANY_8/equipment/info/page.tsx b/frontend/app/(main)/COMPANY_8/equipment/info/page.tsx
index cd53e9b1..f32273ae 100644
--- a/frontend/app/(main)/COMPANY_8/equipment/info/page.tsx
+++ b/frontend/app/(main)/COMPANY_8/equipment/info/page.tsx
@@ -624,8 +624,17 @@ export default function EquipmentInfoPage() {
                       <TableBody>
                         {inspections.map((item) => (
                           <TableRow key={item.id} className="cursor-pointer hover:bg-primary/5" onDoubleClick={() => {
-                            const std = item.standard_value || "";
-                            const tol = item.tolerance || "";
+                            // lower/upper → standard/tolerance 역산
+                            const lower = item.lower_limit !== "" && item.lower_limit != null ? Number(item.lower_limit) : null;
+                            const upper = item.upper_limit !== "" && item.upper_limit != null ? Number(item.upper_limit) : null;
+                            let std = item.standard_value || "";
+                            let tol = item.tolerance || "";
+                            if (lower !== null && upper !== null && !isNaN(lower) && !isNaN(upper)) {
+                              const stdCalc = (lower + upper) / 2;
+                              const tolCalc = (upper - lower) / 2;
+                              std = String(stdCalc);
+                              tol = String(tolCalc);
+                            }
                             setInspectionForm({ ...item, standard_value: std, tolerance: tol });
                             setInspectionEditMode(true);
                             setInspectionModalOpen(true);
diff --git a/frontend/app/(main)/COMPANY_9/equipment/info/page.tsx b/frontend/app/(main)/COMPANY_9/equipment/info/page.tsx
index cd53e9b1..f32273ae 100644
--- a/frontend/app/(main)/COMPANY_9/equipment/info/page.tsx
+++ b/frontend/app/(main)/COMPANY_9/equipment/info/page.tsx
@@ -624,8 +624,17 @@ export default function EquipmentInfoPage() {
                       <TableBody>
                         {inspections.map((item) => (
                           <TableRow key={item.id} className="cursor-pointer hover:bg-primary/5" onDoubleClick={() => {
-                            const std = item.standard_value || "";
-                            const tol = item.tolerance || "";
+                            // lower/upper → standard/tolerance 역산
+                            const lower = item.lower_limit !== "" && item.lower_limit != null ? Number(item.lower_limit) : null;
+                            const upper = item.upper_limit !== "" && item.upper_limit != null ? Number(item.upper_limit) : null;
+                            let std = item.standard_value || "";
+                            let tol = item.tolerance || "";
+                            if (lower !== null && upper !== null && !isNaN(lower) && !isNaN(upper)) {
+                              const stdCalc = (lower + upper) / 2;
+                              const tolCalc = (upper - lower) / 2;
+                              std = String(stdCalc);
+                              tol = String(tolCalc);
+                            }
                             setInspectionForm({ ...item, standard_value: std, tolerance: tol });
                             setInspectionEditMode(true);
                             setInspectionModalOpen(true);