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Photo Information

A Royal Thai Marine, simulating a chemical attack victim, lies still while Thai Reconnaissance Marines cordon off the area during a chemical, biological, radiological, chemical exercise here, Feb. 14. The training was conducted by Thai forces and Marines with the 31st Marine Expeditionary Unit, jointly executing casualty decontamination in a bilateral environment. The training is part of exercise Cobra Gold 2012, now in its 31st iteration. The exercise is a multi-lateral event focused on strengthening the interoperability of all participating military forces. The 31st MEU is the only continuously forward-deployed MEU and remains the nation’s force in readiness in the Asia-Pacific region.

Photo by Cpl. Jonathan G. Wright

U.S., Thai Marines rehearse chemical attack, decontamination situation

14 Feb 2012 | Cpl. Jonathan G. Wright

U.S. and Thai Marines donned hazardous material suits under the hot Thailand sun during a chemical attack exercise here, Feb. 14.

Chemical, biological, radiological, nuclear defense specialists with the 31st Marine Expeditionary Unit participated in a multi-lateral scenario in which they, along with their Royal Thai Marine and Air Force counterparts, responded to a chemical attack on a troop transport truck.

“The target was attacked with possible chemical weapons, requiring us to respond accordingly with whatever it might be,” said Lance Cpl. Anthony Donahoe, CBRN defense specialist with the 31st MEU. “From there, it’s a three-step process to be able to clean all personnel and equipment in a field environment.”

As the assaulted truck’s occupants either collapsed to simulate injuries or took cover on the side of the road, Royal Thai Reconnaissance Marines cautiously swept up to the area, testing the immediate area for possible chemical or radioactive signs. Once it was determined that the area was contaminated with hazardous residue, it was cordoned off and U.S. Marine CBRN response teams acted.

The injured victims were loaded onto personnel sleds and stretchers where they were transported to a field cleansing station made up of two two-man teams with the purpose of quickly removing any initial traces of contamination.

“As part of the emergency decontamination station, we take non-ambulatory casualties and conduct contamination removal and cut them out of their suits,” said Donahoe. “If they’re not properly decontaminated or stripped, contamination on their clothing or gear would degrade from the chemical agent and their bodies would eventually succumb. After that, there’s always the possibility of cross-contamination and the chemical spreading.”

Those victims that were able to function were taken to a separate station which formed a line with various checkpoints. Decontaminators in gas masks and encased in rubber suits instructed the personnel to methodically clean and remove their clothing and gear, washing everything in a bleach water solution.

After the personnel were cleansed and simulated transport for further testing, the truck that was attacked then underwent a decontamination process, where water hoses and sponges finished off the chemical cleaning for the day.

“We have our own techniques in dealing with chemical attacks, but the U.S. Marines also have their own tips and tricks when it comes to CBRN,” said Lt. Cmdr. Pisit Kronthong, a Royal Thai Marine and commander of the Thai Marines who participated in the exercise. “What we learn here we’ll be able to teach everyone else that was not present today.”

Although the U.S. and Thai Marines were occasionally more familiar with certain points throughout the training than the other, the day’s event benefited both forces by allowing them to interact with one other and learn how to operate if a joint CBRN situation took place.

“We both have a very robust capability in responding to this type of incident, so this exercise allows us to come together and share our techniques and procedures,” said Chief Warrant Officer 3 Jonathan Davis, officer in charge of the CBRN element of the 31st MEU. “If an incident were to occur and it became necessary for us to form a combined response force, it helps us to ensure that everyone is rehearsed and that we can respond in a very expedient manner.”

Cobra Gold 2012 demonstrates the resolve of the U.S. and participating nations to increase interoperability and promote security and peace throughout the Asia-Pacific region.

The 31st MEU is the only continuously forward-deployed MEU and remains the nation’s force in readiness in the Asia-Pacific region.


31st Marine Expeditionary Unit