FAA publishes SAFO urging airlines to reinforce lithium battery safety as fire risks spike
The Federal Aviation Administration (FAA) has issued SAFO 25002—Managing the Risks of Lithium Batteries Carried by Passengers and Crewmembers—which warns of a growing hazard posed by lithium batteries in the aircraft cabin.
This alert comes amid a sharp rise in onboard battery-related incidents. The FAA has already recorded 50 incidents on US flights in 2025 involving lithium-ion battery smoke, fire, or extreme heat, some causing injuries and others forcing flight diversions.
Some recent incidents led to passenger injuries and aircraft damage
The FAA’s list of verified lithium battery incidents shows that cabin crew contained many of these before they caused serious damage, but not all:
- August 8, 2025: On an American Airlines flight from Madrid (MAD) to Dallas-Ft Worth (DFW), during taxi from the gate for departure, a passenger’s cellular phone overheated and began emitting smoke. While flight attendants retrieved the cellular phone and placed it in a thermal containment bag, the passenger sustained injuries, and the aircraft’s floor was damaged.
- April 4, 2025: On a United Airlines flight from New Orleans (MSY) to Chicago (ORD), a battery pack stowed in a passenger’s backpack overheated and caught fire. A flight attendant poured water on the backpack and then placed the battery pack into a thermal containment bag. The passenger sustained an injury. The flight diverted to St Louis (STL).
- April 4, 2025: Before the boarding process for a United Airlines flight from St. Louis (STL) to Chicago (ORD), a passenger’s portable battery charger began to overheat and caught fire. Emergency personnel responded and extinguished the fire, and the portable battery charger was placed in a thermal containment bag. The passenger experienced burns and was transported to a hospital.
- December 28, 2024: During the arrival of a Delta Air Lines flight from New York City, NY (JFK) to Los Angeles, CA (LAX), a passenger’s battery pack charger malfunctioned, triggering a thermal runaway that resulted in a fire. Flight attendants contained the fire, and responding ground personnel placed the device in a thermal containment bag. The passenger suffered minor burns but refused treatment.
What SAFO 25002 recommends
SAFO 25002 mainly reinforces existing FAA policies and guidelines on lithium batteries. PackSafe guidelines already restrict spare batteries to the cabin, restrict their amount, and mandate terminal protection.
The FAA closely tracks incidents and provides safety materials, including training videos, for both crew and passengers.
Although SAFOs are advisory only and not legally enforceable, SAFO 25002 provides essential safety guidance to airlines in three areas:
- Integrate lithium battery risks into safety risk management (SRM). Airlines must review the placement of lithium-powered devices—especially in obscured areas, such as overhead bins or carry-on luggage—and assess how these positions may impact detection and response times.
- Revamp firefighting procedures and crew training. While Halon extinguishers may suppress visible flames, they do not stop battery thermal runaway events. The FAA recommends cooling devices with water to fully extinguish and prevent re-ignition. Crews must also be trained to recognise stages of overheating (e.g., smoke versus flame) and equipped with appropriate containment tools.
- Educate passengers and crew about lithium batteries through safety videos, website messaging, and onboard announcements. Guidelines should advise passengers how to safely transport devices (e.g., in accessible, visible locations), how to prevent damage or short circuits (e.g., using protective cases, taping terminals), and to notify crew immediately if a device begins to overheat or emit smoke.
Passengers fly with several lithium-battery-powered devices, increasing incident risks
As electronic devices have become pervasive, many passengers travel with at least one and often more than one device that could ignite.
In September of last year, UL Standards & Engagement shared data from its Thermal Runaway Incident Program (TRIP), showing that the average passenger brings four rechargeable devices powered by lithium-ion batteries on board.
- Top items include smartphones (82%), laptops (41%), headphones (39%), and tablets (36%). In 2023, e-cigarettes caused 35% of reported incidents on passenger flights, followed by power banks, which caused 16%.
- A majority of incidents (87%) occur on aircraft, with 13% occurring when baggage and personal items are moved. Nearly 60% of thermal runaway incidents on aircraft happen near the passenger’s seat.
- Most incidents are resolved before they reach the fire or explosion stage. Over 85% of incidents in 2023 were addressed when batteries showed warning signs such as overheating and smoking. While only 15% of incidents resulted in fire or explosion, thermal runaway can develop quickly enough that the majority of incidents might have been more serious had the issue not been addressed.
The ULSE report also showed that passengers are disregarding FAA PackSafe guidance, with rechargeable devices still being packed in checked luggage.
- Over a quarter (27%) of travellers stored portable chargers and e-cigarettes in checked luggage.
This poses a serious hazard to flight as checked baggage that enters thermal runaway can’t be accessed by the crew, and fires in the cargo hold may not be detected as quickly as in the cabin. With other flammable items stored in the hold, a thermal runaway event could soon endanger the flight.
Some airlines are banning the use of power banks (portable chargers) in flight, and are requesting passengers not only keep them in their hand luggage, but also in a seat pocket where they can be seen at all times.
The threat of lithium-ion battery thermal runaway
Thermal runaway in a lithium-ion battery can rapidly escalate to extreme temperatures. Once the runaway begins, the inside of the cell can spike to 500–700 °C (930–1,300 °F) in seconds.
In one 2024 laboratory test, the flame temperature measured just 5 centimetres from a lithium-ion cell undergoing thermal runaway reached 1,107 °C (2,024.6 °F). Such intense flames can instantly ignite nearby cabin interior materials like plastics or fabrics.
In a multi-cell battery pack (like in laptops), one cell going into runaway can trigger neighbouring cells, compounding the fire and extending burn times. Venting gases (hydrogen fluoride, carbon monoxide, hydrocarbons) are both poisonous and highly flammable, and they often expel under pressure in a “torch-like” jet.
The FAA and airline firefighting guidance stresses cooling with large amounts of water—not just Halon extinguishers. Halon will knock down flames, but it doesn’t lower the runaway temperature, so the cell can reignite once oxygen is reintroduced.
In the pressured, confined environment of an aircraft cabin, such an incident can escalate swiftly. Rapid detection, proper firefighting protocols, and educated passengers are essential to prevent catastrophe.
Airline crew use fire-containment equipment to minimise lithium battery risks
Airlines have equipped their aircraft with containment kits to help manage a lithium-battery fire and trained crew to manage these situations. Some of the devices developed to address the fire risks include:
- Aircare Firesock: Bag withstands internal heat up to 2000°F. Includes a tube to hold around 130 oz of water to douse the fire, plus gloves for handling.
- HOT-STOP ‘L’ Kits distributed by Baker Aviation: Certified as fireproof by an FAA-registered laboratory. Made up of multiple durable fabrics with a felt inner core that has a 1760ºC (3200ºF) melting point. The core is sandwiched between two outer layers that have a 1137.78°C (2080°F) melting point. A military grade zipper keeps the bags airtight, preventing the escape of toxic smoke, gases, and other dangerous emissions.
- AvSax bags: Crews can pour two litres of water into an AvSax bag and insert a device at the first sign of a thermal runaway. Polymer gel inside the bag expands when water hits it, enclosing and cooling the device to reduce fire risk. During thermal runaway, the bag will contain smoke and fire.
As the number of incidents continues to rise, SAFO 25002 is a reminder that lithium batteries remain one of the fastest-growing safety concerns in modern aviation. While crew training, specialised containment equipment, and clear passenger guidance have so far prevented most events from escalating into catastrophe, the risks are real and persistent.
With passengers carrying ever more rechargeable devices on board, airlines and regulators face the ongoing challenge of keeping pace with both technology and human behaviour to ensure the cabin remains safe.
