diff --git a/lib/tablelib.php b/lib/tablelib.php
index 1d5455aa852..b3276f21a57 100644
--- a/lib/tablelib.php
+++ b/lib/tablelib.php
@@ -519,13 +519,13 @@ class flexible_table {
             }
 
             if($this->headers[$index] === NULL) {
-                echo '<th class="header c'.$index.$this->column_class[$column].'">&nbsp;</th>';
+                echo '<th class="header c'.$index.$this->column_class[$column].'" scope="col">&nbsp;</th>';
             }
             else if(!empty($this->sess->collapse[$column])) {
-                echo '<th class="header c'.$index.$this->column_class[$column].'">'.$icon_hide.'</th>';
+                echo '<th class="header c'.$index.$this->column_class[$column].'" scope="col">'.$icon_hide.'</th>';
             }
             else {
-                echo '<th class="header c'.$index.$this->column_class[$column].'" nowrap="nowrap"'.$this->make_styles_string($this->column_style[$column]).'>'.$this->headers[$index].$icon_sort.'<div class="commands">'.$icon_hide.'</div></th>';
+                echo '<th class="header c'.$index.$this->column_class[$column].'" nowrap="nowrap"'.$this->make_styles_string($this->column_style[$column]).' scope="col">'.$this->headers[$index].$icon_sort.'<div class="commands">'.$icon_hide.'</div></th>';
             }
 
         }