diff --git a/docs/DriverLifecycle.md b/docs/DriverLifecycle.md
index ce77f088..60320bc8 100644
--- a/docs/DriverLifecycle.md
+++ b/docs/DriverLifecycle.md
@@ -476,7 +476,7 @@ forces a fresh `PollGroupEngine` subscription whose initial poll runs `forceRais
 the initial push added by 05/STAB-18. What the host does instead is **audit** it — `CommsRecoveryAudit`
 fires `DefaultCommsRecoveryAuditDelay` (30 s) after the driver reconnects and reports any ref still
 latched Bad, as a Warning naming the driver plus the `otopcua.driver.comms_latched_refs` counter (tagged
-`driver`, `driver_type`). That counter going non-zero means a driver reconnected without re-publishing —
+`driver_instance`, `driver_type`). That counter going non-zero means a driver reconnected without re-publishing —
 a push driver missing its initial push, or a value-only dedup swallowing an unchanged value. It is a
 tripwire, not a repair: nothing downstream depends on it.
 
diff --git a/src/Server/ZB.MOM.WW.OtOpcUa.Runtime/Drivers/DriverHostActor.cs b/src/Server/ZB.MOM.WW.OtOpcUa.Runtime/Drivers/DriverHostActor.cs
index dd56ab17..d27c437b 100644
--- a/src/Server/ZB.MOM.WW.OtOpcUa.Runtime/Drivers/DriverHostActor.cs
+++ b/src/Server/ZB.MOM.WW.OtOpcUa.Runtime/Drivers/DriverHostActor.cs
@@ -1540,7 +1540,7 @@ public sealed class DriverHostActor : ReceiveActor, IWithTimers, IWithUnboundedS
         var driverType = _children.TryGetValue(msg.DriverInstanceId, out var child) ? child.DriverType : "unknown";
         OtOpcUaTelemetry.DriverCommsLatchedRefs.Add(
             latched.Count,
-            new KeyValuePair<string, object?>("driver", msg.DriverInstanceId),
+            new KeyValuePair<string, object?>("driver_instance", msg.DriverInstanceId),
             new KeyValuePair<string, object?>("driver_type", driverType));
 
         _log.Warning(
diff --git a/tests/Server/ZB.MOM.WW.OtOpcUa.Runtime.Tests/Drivers/DriverHostActorCommsLossValueNodesTests.cs b/tests/Server/ZB.MOM.WW.OtOpcUa.Runtime.Tests/Drivers/DriverHostActorCommsLossValueNodesTests.cs
index 1454c1ea..ed1d5f0e 100644
--- a/tests/Server/ZB.MOM.WW.OtOpcUa.Runtime.Tests/Drivers/DriverHostActorCommsLossValueNodesTests.cs
+++ b/tests/Server/ZB.MOM.WW.OtOpcUa.Runtime.Tests/Drivers/DriverHostActorCommsLossValueNodesTests.cs
@@ -149,8 +149,8 @@ public sealed class DriverHostActorCommsLossValueNodesTests : RuntimeActorTestBa
         // Two REFS, not three nodes: the latch is keyed by RawPath, and the UNS mirror shares its
         // backing tag's ref — the operator is being told how many tags did not come back, not how many
         // address-space nodes they project onto.
-        AwaitCondition(() => meter.WithTag("driver", SilentDriver) > 0, TimeSpan.FromSeconds(5));
-        meter.SumWithTag("driver", SilentDriver).ShouldBe(2);
+        AwaitCondition(() => meter.WithTag("driver_instance", SilentDriver) > 0, TimeSpan.FromSeconds(5));
+        meter.SumWithTag("driver_instance", SilentDriver).ShouldBe(2);
     }
 
     /// <summary>
@@ -190,7 +190,7 @@ public sealed class DriverHostActorCommsLossValueNodesTests : RuntimeActorTestBa
             publish.ExpectMsg<OpcUaPublishActor.AttributeValueBatchUpdate>(PresenceBudget);
         });
 
-        meter.WithTag("driver", RepublishingDriver).ShouldBe(0);
+        meter.WithTag("driver_instance", RepublishingDriver).ShouldBe(0);
     }
 
     /// <summary>
@@ -227,8 +227,8 @@ public sealed class DriverHostActorCommsLossValueNodesTests : RuntimeActorTestBa
             publish.ExpectMsg<OpcUaPublishActor.AttributeValueBatchUpdate>(PresenceBudget);
         });
 
-        AwaitCondition(() => meter.WithTag("driver", PartialDriver) > 0, TimeSpan.FromSeconds(5));
-        meter.SumWithTag("driver", PartialDriver).ShouldBe(1, "only the ref that never came back is reported");
+        AwaitCondition(() => meter.WithTag("driver_instance", PartialDriver) > 0, TimeSpan.FromSeconds(5));
+        meter.SumWithTag("driver_instance", PartialDriver).ShouldBe(1, "only the ref that never came back is reported");
     }
 
     /// <summary>
diff --git a/tests/Server/ZB.MOM.WW.OtOpcUa.Runtime.Tests/Drivers/DriverHostCommsLossRecoveryTests.cs b/tests/Server/ZB.MOM.WW.OtOpcUa.Runtime.Tests/Drivers/DriverHostCommsLossRecoveryTests.cs
index 4f67cc1b..a2d0b711 100644
--- a/tests/Server/ZB.MOM.WW.OtOpcUa.Runtime.Tests/Drivers/DriverHostCommsLossRecoveryTests.cs
+++ b/tests/Server/ZB.MOM.WW.OtOpcUa.Runtime.Tests/Drivers/DriverHostCommsLossRecoveryTests.cs
@@ -80,7 +80,7 @@ public sealed class DriverHostCommsLossRecoveryTests : RuntimeActorTestBase
         // …and the audit finds nothing outstanding.
         EventFilter.Warning(contains: "still BadNoCommunication")
             .Expect(0, AuditDelay + TimeSpan.FromSeconds(3), () => { });
-        meter.SumWithTag("driver", "drv-recover").ShouldBe(0);
+        meter.SumWithTag("driver_instance", "drv-recover").ShouldBe(0);
     }
 
     /// <summary>
@@ -109,7 +109,7 @@ public sealed class DriverHostCommsLossRecoveryTests : RuntimeActorTestBase
         });
 
         // One ref (the raw tag); its UNS mirror shares it.
-        AwaitCondition(() => meter.SumWithTag("driver", "drv-silent") == 1, TimeSpan.FromSeconds(5));
+        AwaitCondition(() => meter.SumWithTag("driver_instance", "drv-silent") == 1, TimeSpan.FromSeconds(5));
         driver.SubscribeCount.ShouldBeGreaterThanOrEqualTo(2,
             "the child must actually have re-subscribed — otherwise this proves nothing about the push");
     }