<script type="text/javascript" >

    var PageFirstLoaded = new Date().getTime();

    jQuery(window).focus(function(){
      //----- BROWSER WINDOW HAS GOT FOCUS -----
      
      //If page is old reload it
      if(new Date().getTime() - PageFirstLoaded >= 60000)      //mS
         window.location.reload(true);
       
    });

  </script>