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Battery Event Forces Closure of LAX
A “Ho-Hum Incident” or “Something to Ponder?”
by Shirley Georgi
 An Aerial View of LAX, the Los Angeles Airport
With eight domestic terminals and one terminal, The Bradley Terminal, dedicated to international flights, 785,000 passengers were expected to arrive and depart over the Labor Day weekend.
The two incidents on September 4th caused a three hour closure for four terminals and the Central Terminal Area roadway system.
LAX was the third busiest airport in the United States in 2003 and ranked the fifth-busiest in the world. (Photo is courtesy of Media Relations at the Los Angeles Intenational Airport. Special thanks to Tom Winfrey.) +
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The Labor Day weekend provided some excitement for security at both the LAX Airport and the Ontario International Airport (a large airport in the western Greater Los Angeles Area) in California.
At Ontario on Friday - Sept. 3, 2004, a cosmetics bag inside a makeup case triggered an alarm for explosives and therefore, the airport’s Terminal 4 had to be evacuated for two hours The cosmetics were examined and were declared to be of no threat to security.
At LAX on Saturday - Sept. 4, 2004, two separate, unrelated incidents occurred and caused a shutdown of four terminals at this largest airport in Los Angeles for four hours. The incidents are reported as follows:
• At 7:30 AM, a person bypassed security at United Airlines in Terminal 8 when he ran up an exit stairway from the lower level baggage claim area and thus entered a secured area. Because Terminals 6, 7 and 8 are connected, all three terminals were evacuated and all passengers were rescreened to insure safety. The man inciting the incident was not found.
• In a separate incident at 8 o’clock AM in the Tom Bradley International Terminal, two “old” batteries exploded. (Since battery safety has been a prime interest of Batteries Digest, information gathering began as soon as the incident was broadcast on the radio.) The official press release from the LAX media center read, “...a plastic flashlight exploded as the contents of a passenger’s check luggage were being examined by a Transportation Security Authority (TSA) employee at the Tom Bradley International Terminal. Two TSA employees were slightly injured and several other people complained of ringing ears from the sound of the explosion. The Tokyo-bound passenger cooperated with authorities and was not arrested. Officials believe the flashlight’s batteries had released a gas in the sealed plastic container which led to the small explosion.”
On-the-scene reporters from the large news agencies such as Rueters and the Associated Press as well as local news media were on hand as soon as possible to catch a few extra details. As a result, here are some of the statements written and quoted about the battery incident:
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An example of a leaking Alkaline-magnesium dioxide Battery
While BD does not have proof that the LAX battery was primary Alkaline, its popularity and availability suggests that it is the most likely the type involved. Although used in millions of devices, the Alkaline battery occasionally develops a leak as shown in the cell shown here. Leaking electrolyte can lead to hydrogen gas derived from the water/potassium hydroxide electrolyte.1
The leak could be the result of a poor manufacturing process, or it could have been caused by the sharp edges of the contacts of the flashlight battery terminal connector. Observation of this particular cell shows damage to the outer plastic wrap pointed to by the arrows. Such damage could have been inflicted by scraping the sharp edges of the cheap spring type connectors of the flashlight in which this battery was found.
The possibility of the LAX battery being Zinc-carbon is not ruled out as it is also a very popular chemistry and more prone to case corrosion. The Zinc-chloride form is well-known for excessive hydrogen gas formation due to zinc dissolution.2 Safety precautions for both Zinc-carbon and Alkaline-magnesium dioxide batteries are usually identical. A prime difference is the electrolyte. The electrolyte in Zinc-carbon batteries is composed of zinc-chloride (ZnCl2) but in some cases can also contain a small amount of ammonium chloride (NH4Cl) to ensure high rate performance. Alkaline batteries use a concentrated potassium hydroxide (KOH) electrolyte (range 35 to 52%). The Alkaline-magnesium dioxide batteries have high capacity compared with Zinc-carbon and are the most popular primary battery in the industrialized nations.+
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n “The TSA worker suffered swollen hands and was taken to a hospital,” Amy von Walter, a TSA spokeswoman said.
n “Preliminarily, it looks like it was a flashlight battery over in the Bradley Terminal,” Cathy Viray, an FBI spokeswoman said. “When it was going through screening, the TSA individual touched it and at that point it exploded.”
n “The Plastic pieces broke apart sending what in effect would be plastic shrapnel, causing one employee to fall backwards, knocking another one down,” stated John Miller, commanding officer of the Los Angeles Police Department’s critical incident management bureau. He also commented on the flashlight exploding because of a buildup of gases from the batteries.
n Kerry Cavanaugh of the Los Angeles Daily News was one of the few reporters to note that the batteries were Type C.
n At a news conference, Los Angeles Mayor Jim Hahn stated, “At this time we don’t believe the explosion involved any intentional explosion or explosive device, but that remains under investigation.”
n Some reports said the battery was corroded which did not prove to be accurate after an investigation was complete.
After reading at least 10 reports on the incident, the BD staff decided to see if more information could be tracked about the battery. The media relations person for the Los Angeles Airport, Tom Winfrey, said he did not have any additional information. In asking questions about the battery, he noted that the TSA might have more information. At TSA, Amy von Walter confirmed that two C-sized batteries had caused the problem by eroding , but her agency was not worried about the battery at this point. When asked about the battery exploding, she said that a battery condition might better be described as combusting; it had a loud popping sound. She emphasized that the job of her agency was to prevent weapons and explosives from entering the secured airport areas and planes. She felt that the best source to find out more about the battery was through the Los Angles Police Department (LAPD) who actually took the batteries for analysis.
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Editor’s Comment:
Moving from highly unlikely to a reality
Had someone proposed the chain of events which led to the LAX battery incident prior to the event, his or her respect within the technical community would definitely be impaired and the image with the general public would have been in the domain of a ‘wierdo,’ or at least someone to place as far away as possible. Even today, the average antiterrorism ‘expert’ would dismiss its happening as nothing to be concerned with or to pursue. Script writers for Harry Potter would have deep-sixed it as too unbelievable.
But moving beyond six sigma and government budget limitations into the realm of scientific dedication, incidents such as the LAX battery could provide insight into increased safety design and testing of many new battery-operated products. Move the ‘weirdo’ designation aside. No longer could such a chain of events be highly unlikely; it did happen and there is nothing to preclude it happening with the same or different outcome in the future.
The first observation of the event focuses on the system. The battery by itself in a test over a few days, weeks or months would never have experienced such a result. It required enclosure in a sealed container and possibly needed help from a not-very-well designed terminal clip to expedite seal damage. A complete test would involve testing the battery within the product.
Are there things which the battery manufacturer could have done to stop the event? How about the battery connector? What could the flashlight manufacturer have done to eliminate the event? The requirements for the ‘explosion’ were hydrogen from the leaking electrolyte, oxygen from the air and heat from a spark. The battery manufacturer did not supply the air or the spark.
But the battery manufacturer probably provided a commercially acceptable cell, and the flashlight probably worked well enough to make the owner satisfied. The TSA probably moved on without concern, except for the unfortunate employee who held the ‘popping’ flashlight. All the passengers had an uneventful flight.
But the flashlight and batteries were taken out of the realm of public domain. For all we know, they were put in the dumpster. Did no one want them? Hardly! Many battery manufacturers might have liked to examine them for forensic analysis. BD’s parent engineering company would have gladly paid the LAPD the purchase price plus shipping for the assembly. Or imagine what a respectable engineering college would have paid to get the assembly as a basis for a design class which focused on failure mode and effects analysis. Whoever would have gotten the assembly and used rigorous analytical methods could have had a write up which could expand the way battery-operated devices are designed and evaluated.
If there is no other outcome than to make a few test engineers expand the scenarios for their work, the LAX battery may have served its purpose.
DKG
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Officer Lee at the LAPD’s office said that batteries had been examined by his department, but because the incident was determined to have no criminal intent, there was no formal report on the battery and that only a few internal memos had been written about it. Since the battery was not needed as evidence, it was no longer available at the LAPD. However, he said he would share the limited information he had.
Evidently, the C-sized batteries were in a waterproof flashlight. The flashlight itself was determined to be approximately 25 years old although he did not know who was the manufacturer of the flashlight or the battery. The C-sized batteries, he noted, were ordinary batteries, perhaps five or six years old. The professional judgment of the investigators was that over a period of time, the batteries had begun to leak a small amount of hydrogen. The hydrogen had no way to escape, and thus the gas remained in the compartment because it was sealed. In some manner, perhaps by a loosening spring rubbing on the battery, a spark was ignited as the flashlight was opened, and as a result, the excaping hydrogen mixed with oxygen in the air and exploded.
Although it can only be assumed that this “ordinary” battery was most likely Alkaline or Zinc-carbon, other chemistires cannot totally be ruled out. Information from the LAPD seems to be substantiated when reading Energizer’s Product Safety Data Sheets on both Alkaline and Zinc-carbon, which discuss the potting or sealing of the battery in an airtight or watertight container. In the section under Mechanical Containment, it reads: “Batteries normally evolve hydrogen which, when combined with oxygen from the air, can produce a combustible or explosive mixture unless vented. If such a mixture is present, short circuits, high temperature, or static sparks can cause an ignition.”
In further questioning about the chemistry of the battery, the LAPD officer would only say the battery was an “ordinary” C-sized battery, and he added that he had no knowledge of its chemistry.
Thus, the incident of the exploding battery which had a “full charge” of investigative interest on Saturday morning degraded to ‘fully discharged” interest and was no longer a pertinent issue by Monday of the following week.
Should this incident be of interest to the battery manufacturing and utilizing community?
Although most of the safety concerns in the literature recently has been about lithium batteries, Alkaline and Zinc-carbon, thought to have a more benign chemistry, can cause problems, too, if they are abused or used improperly. Both Duracell and Energizer, the two largest brand names, have safety specifications data sheets and spend resources on telling the public about using batteries safely.
For example, Gillette, parent of Duracell, has created excellent consumer awareness for safety of the Alkaline cell. Because the common Alkaline-manganese dioxide battery does contain hazardous decomposition products, consumers are told to handle the battery carefully (i.e. the battery should not be thrown into a purse or container where it can be abused, as in hitting other objects or other batteries.) Duracell is also careful to note that “thermal degradation may produce hazardous fumes of zinc and manganese; hydrogen gas; caustic vapors of potassium hydroxide and other toxic by- products.” However, a potential for exposure should not exist unless the battery leaks, is exposed to high temperatures and/or is somehow mechanically, physically, or electrically abused. This Alkaline-manganese dioxide chemistry contains concentrated (35%) potassium hydroxide electrolyte, which in itself is caustic. If an Alkaline cell does leak and an individual is exposed, respiratory and/or eye irritation may result and possibly an individual could suffer a burn.
Best practices for anyone handling batteries should be:
- Store at room temperature.
- Avoid mechanical or electrical abuse.
- Install correctly according to directions.
- Do not disassemble or crush batteries. They could explode or pyrolyze or vent.
- Do not ever try to recharge a primary battery.
- Never mix chemistries. For example, if two or more Alkaline battery cells are needed, all cells need to be primary Alkaline-Manganese dioxide. Do not put in another type of battery such as Carbon-zinc, even if it is the same cell size.
- Replace all batteries in the flashlight or other apparatus at the same time.
- Remove discharged batteries from the flashlight or other battery-powered device.
- Always keep batteries away from small children.
Alkaline and Carbon-zinc batteries are not regulated by the U.S. Department of Transportation (DOT) or international agencies as hazardous materials or dangerous goods when shipped.
The major battery companies with brand names have worked very ardently to make safe batteries and to make warning labels and notations concerning safety standards for consumers’ usage. However, with numerous branded and unbranded named companies in China, alone, manufacturing 20 billion units of primary batteries in 2003, primary batteries are becoming a commodity. Public awareness of using such electrochemical devices properly is not a “ho hum” issue. If the TSA agent had not been so careful in examining the flashlight, what could have happened if the passenger decided to examine the batteries in his or her flashlight during the flight on the plane? It may not be a terrorism attack, but it could have potentially caused a significant event.
Reference
1. Handbook of Batteries, Third Edition. p.10.3
2, Handbook of Batteries, Third Edition. p.8.13
BD