diff --git a/lib/helpers/HttpStatusCode.js b/lib/helpers/HttpStatusCode.js
index b3e7adca..b68d08e1 100644
--- a/lib/helpers/HttpStatusCode.js
+++ b/lib/helpers/HttpStatusCode.js
@@ -62,6 +62,12 @@ const HttpStatusCode = {
   LoopDetected: 508,
   NotExtended: 510,
   NetworkAuthenticationRequired: 511,
+  WebServerIsDown: 521,
+  ConnectionTimedOut: 522,
+  OriginIsUnreachable: 523,
+  TimeoutOccurred: 524,
+  SslHandshakeFailed: 525,
+  InvalidSslCertificate: 526,
 };
 
 Object.entries(HttpStatusCode).forEach(([key, value]) => {