HONOLULU (KHON2) — Honolulu Emergency Medical Services is putting some ambulances out of service, after an ambulance went up in flames last week, killing a patient. Other safety measures are also in the works.

The ambulance was transporting a 91-year-old patient to Adventist Health Castle Hospital went it caught on fire. The paramedic who was with the patient who died was critically injured and remains in the hospital.

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EMS has sent a memo to staff saying it has “Removed from service the vehicles of the same series.” An EMS spokeswoman said there are three such vehicles and EMS has enough in its fleet to cover all units.

“I’m pleased that they’re doing that, it is the responsible thing for EMS leadership to do,” said Bobby Lee, president of the Hawaii Fire Fighters Association.

The firefighters’ union had asked its members not to ride in ambulances shortly after the incident. But has since backed off on that. Lee said firefighters will feel better about this latest move.

The memo also said that EMS has contracted an outside investigator in addition to the Honolulu Fire Department, Bureau of Alcohol, Tobacco, Firearms and Explosives, and the Honolulu Fire Department. And hired a consultant to assist with reviewing protocols.

“I think it’s always better the more people you get involved in an accident situation like this. So that is the right thing for them to do,” said Lee.

He said it could take several months to determine the cause of the fire. So any precautions that can be taken now should be done, and protocols should be evaluated.

“When you do get something like this, you have to go above and beyond to look at everything. Not just the equipment but policy procedures and make sure people are following the procedures too,” said Lee.

The memo adds that EMS has also initiated a review of safety procedures.

Lee said investigators will likely put a lot of attention on evaluating the oxygen system in the ambulances. Each one is usually equipped with a large tank of oxygen that is fixed to the vehicle and there are also smaller portable tanks.

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“When they get to the hospital, they will usually transfer from the fixed system to a portable unit when they have to take the patient out of the ambulance,” said Lee.