diff --git a/websocket-sharp/WebSocket.cs b/websocket-sharp/WebSocket.cs
index 242f8ecf..d06ef020 100644
--- a/websocket-sharp/WebSocket.cs
+++ b/websocket-sharp/WebSocket.cs
@@ -2552,12 +2552,37 @@ namespace WebSocketSharp
     /// </param>
     public void Close (ushort code, string reason)
     {
-      string msg;
-      if (!CheckParametersForClose (code, reason, _client, out msg)) {
-        _logger.Error (msg);
-        error ("An error has occurred in closing the connection.", null);
+      if (!code.IsCloseStatusCode ()) {
+        var msg = "Less than 1000 or greater than 4999.";
+        throw new ArgumentOutOfRangeException ("code", msg);
+      }
 
-        return;
+      if (_client && code == 1011) {
+        var msg = "1011 cannot be used.";
+        throw new ArgumentException (msg, "code");
+      }
+
+      if (!_client && code == 1010) {
+        var msg = "1010 cannot be used.";
+        throw new ArgumentException (msg, "code");
+      }
+
+      if (!reason.IsNullOrEmpty ()) {
+        if (code == 1005) {
+          var msg = "1005 cannot be used.";
+          throw new ArgumentException (msg, "code");
+        }
+
+        byte[] bytes;
+        if (!reason.TryGetUTF8EncodedBytes (out bytes)) {
+          var msg = "It could not be UTF-8-encoded.";
+          throw new ArgumentException (msg, "reason");
+        }
+
+        if (bytes.Length > 123) {
+          var msg = "Its size is greater than 123 bytes.";
+          throw new ArgumentOutOfRangeException ("reason", msg);
+        }
       }
 
       close (code, reason);