This paper presents the use of human factor analysis and classification system (HFACS) for the explosion in the Texas Tech University laboratory. Human factor issues in the university laboratory were assessed according to four categories in HFACS: unsafe acts, precondition for unsafe acts, unsafe supervision, and organizational influences. The assessment showed that the student committed many errors due to precondition for unsafe acts, in particular no physical hazard evaluation required prior to conducting the experiment. Inadequate supervision in the university laboratory caused the presence of precondition for unsafe acts among students. The trajectory of human factor issues in the categories of unsafe acts, precondition for unsafe acts, and unsafe supervision pointed to the university’s organization. The human factor issues were analyzed according to three subcategories in organizational influences: resource management, organizational climate, and organizational process. The use of HFACS in the explosion in the Texas Tech University laboratory could demonstrate the sequence of failures and human factors leading to the accident.