diff --git a/.changeset/dirty-eggs-deliver.md b/.changeset/dirty-eggs-deliver.md
new file mode 100644
index 00000000000..bbd338d1a76
--- /dev/null
+++ b/.changeset/dirty-eggs-deliver.md
@@ -0,0 +1,5 @@
+---
+'@firebase/performance': patch
+---
+
+Expand check in `getServiceWorkerStatus` to account for a `navigator` that has a key of `serviceWorker` with a falsy value
diff --git a/packages/performance/src/utils/attribute_utils.test.ts b/packages/performance/src/utils/attribute_utils.test.ts
index ba258ddf37c..fa7a43d901b 100644
--- a/packages/performance/src/utils/attribute_utils.test.ts
+++ b/packages/performance/src/utils/attribute_utils.test.ts
@@ -32,12 +32,20 @@ import '../../test/setup';
 
 describe('Firebase Performance > attribute_utils', () => {
   describe('#getServiceWorkerStatus', () => {
+    it('returns unsupported when service workers is in navigator but has a falsy value', () => {
+      stub(Api, 'getInstance').returns({
+        navigator: { serviceWorker: undefined }
+      } as unknown as Api);
+
+      expect(getServiceWorkerStatus()).to.be.eql(1 /** UNSUPPORTED */);
+    });
+
     it('returns unsupported when service workers unsupported', () => {
       stub(Api, 'getInstance').returns({
         navigator: {}
       } as unknown as Api);
 
-      expect(getServiceWorkerStatus()).to.be.eql(1);
+      expect(getServiceWorkerStatus()).to.be.eql(1 /** UNSUPPORTED */);
     });
 
     it('returns controlled when service workers controlled', () => {
@@ -49,7 +57,7 @@ describe('Firebase Performance > attribute_utils', () => {
         }
       } as unknown as Api);
 
-      expect(getServiceWorkerStatus()).to.be.eql(2);
+      expect(getServiceWorkerStatus()).to.be.eql(2 /** CONTROLLED */);
     });
 
     it('returns uncontrolled when service workers uncontrolled', () => {
@@ -59,7 +67,7 @@ describe('Firebase Performance > attribute_utils', () => {
         }
       } as unknown as Api);
 
-      expect(getServiceWorkerStatus()).to.be.eql(3);
+      expect(getServiceWorkerStatus()).to.be.eql(3 /** UNCONTROLLED */);
     });
   });
 
diff --git a/packages/performance/src/utils/attributes_utils.ts b/packages/performance/src/utils/attributes_utils.ts
index ef3f499e23b..074a4deb66a 100644
--- a/packages/performance/src/utils/attributes_utils.ts
+++ b/packages/performance/src/utils/attributes_utils.ts
@@ -59,7 +59,7 @@ const MAX_ATTRIBUTE_VALUE_LENGTH = 100;
 
 export function getServiceWorkerStatus(): ServiceWorkerStatus {
   const navigator = Api.getInstance().navigator;
-  if ('serviceWorker' in navigator) {
+  if (navigator?.serviceWorker) {
     if (navigator.serviceWorker.controller) {
       return ServiceWorkerStatus.CONTROLLED;
     } else {