FORT POLK, La. -- For the first time in 13 years, the Army is testing a chemically and biologically protected deployable hospital. The test involving the 115th Combat Support Hospital, took place in the parking lot of Alligator Lake north of Fort Polk April 19.

The system uses plastic tent liners and positive pressurization to keep out dangerous airborne contaminants

Col. Kathleen Ryan, 115th evaluated how well hospital staff could function around the new equipment.

"Right now, we've got an 84-bed package set up," said Ryan. "It's the first time we're going to test moving in patients (patient scenarios) since 1997. We have a locked down, isolated, pressurized unit to keep out these so-called chemical contaminants from coming in."

The last time the system was tested was at Fort Carson, Colo. Since then, many aspects of the deployable hospital have improved.

The hospital includes an emergency medical treatment area, two intensive care units, intermediate care ward, operating room, X-ray lab, blood lab and pharmacy. The hospital, containing these different facilities, must stay sealed off from the outside during the test.

Anyone entering the hospital must spend three minutes in decontamination, either standing in a velcroed canvas chamber or in on a litter in a small plastic tube.

"As a casualty, when you come into the system and as you get decontaminated, I'm looking at what's happening to you as an injured patient, how that system works, are you breathing or bleeding - because you have to spend three minutes in that decontamination process, and those are three critical minutes," said Ryan.

For the test itself, Soldiers of the 115th simulated injuries. Some had bandages dyed red, others had glue on their faces to mimic vomit. Whether on litters or able to walk, patients were ushered through an outdoor decontamination simulation, wiped down with sponges and sent in. If they could walk, they waited in the canvas chamber. If they could not, they were put into plastic tubes for a few minutes so contaminated air could be exchanged for hospital air.

Lt. Col. Michael McCoy of the Army Medical Department out of Fort Sam Houston in San Antonio, Texas, was there to see how the new equipment held up under use.

"This test is to combine the liners, look at the improvements and combine it with the different shelters," said McCoy. "In 1997, you didn't have the same medical equipment. Combine all that, and we hook up the power, water, liners and capabilities and we ask the users how does it work, does it interfere with what they do and how much'"

Usually, a deployable hospital is not going to be in a chemical/biological mode. The tent liners, when not pressurized by the air system, is more likely to sag and take up tent volume, potentially interfering with the number of beds the hospital can accommodate.

"When we bring in casualties, we have to look at the way the technology works behind it. That allows the clinicians to do their work," said McCoy. "If it interferes, then we need to go back to blend the technology with the business process so we're not causing harm."

The test is also in place to determine whether the clinical process can harm the new, thicker plastic liners.

"We just want to get a response, to validate that it works fine, but also we want to look at anything that could cause problems, whether that be safety issues, rips, tears, that sort of thing, because it is plastic," said McCoy.

"It's a pretty hardy plastic, but you always take that risk that you cause a tear doing something and you get a safety issue, a risk from the outside."

Besides being a test of updated technology, setting up the hospital is valuable practice for Soldiers new to the 115th CSH.

"This is a first time for many of these Soldiers," said Ryan. "We have pretty much a 90 percent turnover in personnel. New folks have arrived, and it's their first time, and we start them on a cycle for our rotation or next mission."

"This is the first time in a long time that we've set up an 84-bed," said Master Sgt. Dolores Hernandez of the 115th CSH. "The Soldiers have done an awesome job. They all worked together as a team. This is their product and it is great."