diff --git a/src/index.js b/src/index.js
index 9e8a4df..7abd952 100644
--- a/src/index.js
+++ b/src/index.js
@@ -137,9 +137,10 @@ window.addEventListener('pagehide', ((event) => sampleRUM.leave(event)));
 
 const observer = new PerformanceObserver((list) => {
   list.getEntries()
-    .filter((entry) => (entry.responseStatus < 400) && new URL(entry.name).pathname.match('.*(\\.plain\\.html|\\.json)$'))
+    .filter((entry) => !entry.responseStatus || entry.responseStatus < 400)
+    .filter((entry) => new URL(entry.name).pathname.match('.*(\\.plain\\.html|\\.json)$'))
     .forEach((entry) => {
-      sampleRUM('resource', { source: entry.name, target: Math.round(entry.duration) });
+      sampleRUM('loadresource', { source: entry.name, target: Math.round(entry.duration) });
     });
 });
 observer.observe({ type: 'resource', buffered: true });