As conceptualized and put forward by Kletz, avoiding hazard at first instance is always desirable than trying to protect or manage it. However, there could be certain hazards which may not be possible to be totally eliminated and thus shall be analyzed and assessed in order to either reduce the probability of occurrence or limit the severity of consequences. Trevor's methodologies on HAZOP and hazard analysis (HAZAN) for process hazards are quite straightforward where the hazard is considered as a point source unlike hazmat transportation which is a moving source of hazard. The authors applied the HAZAN techniques to the transportation risk assessment of three different United Nations classes of hazardous materials (hazmats) through important industrial corridors of Surat district in western India that helped local authorities not only to decide on the minimum risk routes to regulate hazmat traffic but also to prepare an effective evacuation and emergency response strategies. (C) 2012 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.