The official in charge of the investigation of any structural failure, fire, explosion, or industrial or transportation accident which results in the loss of human life, except when caused by a natural disaster or war, may secure for no more than twelve hours so much of the site where it occurred as, in his opinion, may be necessary to gather evidence regarding the cause of the occurrence. No owner or lessee of the site may be denied entrance except to prevent the destruction of evidence. In cases of fire from any cause, the chief or other authorized officer of any fire department or fire company in command at the fire shall have the rights and authority granted to him and his subordinates upon his order or direction by § 27-17.1. Nothing in this section shall limit or otherwise affect the authority of, or be construed to deny access to such site by, any person charged by law with the responsibility of investigating any such accident.