Section 415. Head house and trap doors

Latest version.

Every underground working over forty
  feet  deep  shall  have a proper head house and proper trap doors which,
  when installed subsequent to the effective date of this  act,  shall  be
  constructed of fire-resistant material.

                    
                        var val = document.getElementById('citecontent').innerHTML;
                        art.dialog.defaults.title = window.location.href;
                        art.dialog.data('cite', val);
                        art.dialog.data('homeDemoPath', '/Scripts/plus/artDialog/');
                        art.dialog.open('/Scripts/plus/artDialog/citeiframe.html');