SO you like to go to extremes. The Natick Soldier Systems Center has just the place for you: the Doriot Climatic Chambers.What climate in the world would you prefer to experience? Doriot can give you temperatures from minus 70 to 165 degrees, winds up to 40 mph, humidity from 10 to 90 percent or--grab your umbrella--as much as 4 inches of rain per hour. Varying amounts of sunshine can be simulated by six rows of 250-watt light bulbs.It's all done to help improve the performances of people and equipment with the goal of making life better for Soldiers in the field."This building is designed to mimic every environment on the face of the planet and some places a little bit further," said Col. Keith L. Hiatt, until recently the medical director of the U.S. Army Research Institute of Environmental Medicine at Natick. "There's a lot of places that have chambers, but I think these are the only man-rated chambers, rated to be safe enough to put human beings in."While USARIEM uses Doriot to study Soldier physiology, the Army Materiel Command directs its efforts toward testing everything the Soldier wears and uses. As Hiatt pointed out, however, crossover does occur during research in the chambers."This is a nice marriage between Army Materiel Command and Medical Research and Materiel Command, because we're both on the same post," Hiatt said. "We're working together on a lot of things. They do the 'skin out.' We do the 'skin in.' It's a nice marriage, because that's the total Soldier."Doriot has been a one-of-a-kind facility since its doors first opened in 1954 during the height of the Cold War. Back then, the next conflict seemed likely to take place in Europe. Now Americans are fighting in Southwest Asia, under entirely different climatic conditions.For nearly six decades, Doriot has allowed scientists to observe how people and equipment perform in nearly any environment imaginable without the need of costly field testing. The folks at Doriot can simulate pretty much anything."To do even a weeklong study somewhere, the cost is astronomical," said Josh Bulotsky of Natick Soldier Research, Development and Engineering Center, the chambers manager. "You come here, and everything's here for you. It's all set up. It's ready."It's not like you're in the field and you have no support. It's just a better way to do it. You do your testing. You have your data. There (are) no outside variables at all. You have such a consistent temperature and humidity range."This doesn't mean it will be comfortable inside the chambers during studies and testing. "If you go in there and it's minus 50 or minus 60, and there's no wind, it's really not that cold," Bulotsky said. "But the minute that you even turn the wind up to 10 miles an hour, you immediately give them a risk of having some serious frostbite."Through studies and tests at Doriot, however, researchers have learned how to protect servicemembers from such brutal conditions. "We actually did a study with some SEALs about two and a half years ago, where we put them in there with some (clothing)," Hiatt recalled. "And they were at minus 70 with about a 30 mile-an-hour wind, and they were warm."The two 60-by-10-by-15-foot chambers make this research possible. One chamber can produce arctic conditions. The other can transport you to the tropics, even in the middle of a harsh New England winter. The ample size of the chambers allows for the testing of larger pieces of equipment, such as parachutes or windmills."It's a unique facility," Hiatt said. "It's basically a wind tunnel."In physiological studies conducted at Doriot, human research volunteers--Soldiers temporarily assigned to Natick after Advanced Individual Training--are subjected to heat and cold extremes, and their adaptability is measured. New clothing items are also tested for their warming or cooling properties."If it wasn't for the HRV program, we wouldn't be here," said Bulotsky, "none of us."Hiatt agreed, noting, "The HRVs are integral. You could do a lot of stuff here without them, but there'd be an awful lot of stuff you could not do without them."Soldiers simulate work rates in extreme conditions at Doriot by walking or running on treadmills, often with a full equipment load. Each chamber features two five-person treadmills that can be set as high as 15 mph with a 12-percent grade."We've done…tests where the Soldiers have walked on the treadmills for…2 1/2 hours at a time, with their full gear, trying to figure out how much water…they need to consume," Bulotsky said. "Those tests are pretty rigorous."Those five Soldiers are all marching at the same elevation, the same speed. They're all the same. They all are basically baselined the same."The effects of nutrition on performance can be studied through the use of an in-house kitchen to prepare meals at Doriot, and an on-site dormitory accommodates sleep studies. Dressing rooms with shower and laundry facilities support longer studies."You can basically keep folks here for prolonged periods of time," Hiatt said. "We've done studies that were up to two weeks."Hiatt pointed out that researchers closely monitor volunteers at Doriot. "We make sure that we mitigate all risks and that everybody stays safe," he said. "They're wired up like you can't imagine."Hiatt, Bulotsky and others who work with them never lose sight of the human factor. "All the Soldiers I see come in here, the volunteers, they all give it, for the most part, their hundred percent and more," Bulotsky said. "They're in here so much, you get friendly with them. And they go off, and they get put in harm's way. It's tough sometimes."Soldiers often return from deployments to provide comments on products they helped test at Natick that they later used in the field. "They get a lot of feedback from the Soldiers who are deployed, which is a great thing," Bulotsky said. "It's the only way, I guess, to improve your product."Much as he would like to deploy with them, Bulotsky understands that he can accomplish more for Soldiers at Doriot. "Whatever we can do to make their lives better and safer, when we can't be over there, that's the most important thing," he said. "We're probably more (helpful) here as a whole trying to develop things for them."I enjoy working here. You get to definitely see results. Every day is different."The chambers were named for Brig. Gen. Georges F. Doriot. During World War II, Doriot and the staff at the Quartermaster Corps developed clothing and equipment for Soldiers, tested them under harsh conditions and fielded the improved items as quickly as possible. After that experience, Doriot wanted a facility built to better test Soldiers and equipment."So after the war, it was (Doriot's) idea to come up with a facility, the 'Institute of Man,' I think it was called way back then," Hiatt said. "He wanted a place where he could simulate the worst environments on the planet, so basically from Antarctica to the Sahara Desert and everything in between."The chambers bearing his name have more than realized Doriot's vision. They have been upgraded often over the years to ensure that they remain state-of-the-art facilities. More modernization will likely occur in advance of a future that can't be accurately predicted."The problem is," said Hiatt, "where we fight today may not be where we fight tomorrow."