The National Transportation Safety Board (NTSB) issued two safety recommendations related the transportation of lithium batteries on cargo aircraft.
1. Physically separate lithium batteries from other flammable hazardous materials stowed on cargo aircraft
2. Establish maximum loading density requirements that restrict the quantities of lithium batteries and flammable hazardous materials
Although the Department of Transportation (DOT) was barred by Congress in 2012 from establishing lithium battery safety regulations more stringent that those established by the International Civil Aviation Organization (ICAO), the NTSB is using an allowed exception to the law if it has "credible evidence of a deficiency in the international regulations that has substantially contributed to the start or spread of an on-board fire." The NTSB is citing its investigation of the July 28, 2011, in-flight fire and crash of Asiana Airlines Flight 991.