A flag that has survived actual "bombs bursting in air" can surely survive anything, right? You’d be surprised. Maintaining the Star-Spangled Banner is a monumental task. Jennifer Jones, Curator in the Division of Armed Forces History, and Suzanne Thomassen-Krauss, textile conservator in charge of the preservation of the Star-Spangled Banner, went into the Banner's chamber to perform an examination of the flag. Intern Peter Olson interviewed Suzanne to learn more about how to conserve a priceless symbol of America.

The Star-Spangled in its protective chamber. The flag is on display in Flag Hall of the National Museum of American History.

The Star-Spangled Banner is one of the core symbols of America. Seldom a week goes by that Americans aren't reminded of the flag or the anthem it inspired, especially in 2014 as we celebrate the anthem's 200th anniversary. The Banner has survived thanks to a combination of a family taking care of their treasured relic, luck, and diligent conservation.

Suzanne Thomassen-Krauss (left) and Jennifer Jones (right) checking areas that will act as a "canary in a mine," providing early warning of changes.

"What happens with long-term exhibitions like the Star-Spangled Banner is you want to do periodic examination, look at it every once in a while. We target areas we want to monitor," says Suzanne. This is a smart approach to conservation of such a large object. "You forget how big it is until you're standing next to it," she continues. "Flags of this size have a very hard life."

A microscopic look at individual fibers from the Star-Spangled Banner. "Conservators look for scales and surface proteins that show the condition of the flag. When we bring samples back we use a digital microscope that can do a 3000x magnification. That’s when we’re really looking for those fine little microfractures that can occur on the fibers."

Even though the flag is huge, at present approximately 33 feet by 30 feet, conservators look at the tiniest sample to get some of their largest insights into the condition of the flag. "What we're looking for in particular with the wool … wools are supposed to have scales showing. It's very characteristic of it. So if we start noticing that the scales are disappearing on the surface, if we can't see them anymore, then that tells us that the actual proteins are breaking down. It's having a lot of issues of abrasion probably also. So we're looking for that, and we're also looking for things like…If you start looking at the ends of these fibers you can see where they’ve broken off and they look like a glass rod that's just shattered, that tells us the protein is also getting very fragile. So that's why I pulled a few fibers, just to see how they were."

The flag hung vertically for almost 40 years. Now it’s at a 10 degree angle in an hypoxic environment which protects the flag by reducing oxygen damage and suppressing fires.

What did these fibers tell the conservators? "This is the way they looked when we saw them in 1998, so the good news is that we're not seeing a lot of other fractures along these fibers," says Suzanne. "In the years that it's been in the chamber, it hasn't had a significant change in the proteins or the mechanical properties of the wool. That's very good news."

As wonderful as the flag is, its home is almost as amazing. The flag is housed in a low-oxygen environment that prevents oxidative damage to the wool, cotton, and dyes. Suzanne adds: "Low oxygen should be a benefit to all the materials because all of the materials are organic and oxygen is required to break them down." The gentle angle allows the fibers to relax, reducing stress and the threat of gravity causing fibers to break.

Suzanne Thomassen-Krauss and Jennifer Jones examine a section of the flag. The cotton stars were created in 1813 by reverse appliqué method. Each star was stitched into place on one side of the flag and the cloth on the other side was then cut away to reveal it.

The chamber also protects against light. Light is the bane of any textile—and flags are exposed to a lot of it. The Star-Spangled Banner flew over Maryland's Ft. McHenry during the War of 1812. Before that, Mary Pickersgill assembled it in a hops drying room of Claggett's brewery. After that, the flag was stored in less than ideal conditions.

When it eventually came to the museum, it was hung vertically in natural light for almost four decades. Suzanne revealed a cool fact that most wouldn't think to consider: "The wool chemists tell me [degradation] starts on the back of the sheep before we even work it into a wool."

The same chamber that provides a safe environment for the flag isn't as kind to humans. "It's extremely exhausting to work in extremely low oxygen levels," says Suzanne. "At about 14-15% it's the equivalent of working at about 10,000 foot elevation. The table and the gantry are mechanically cranked. So it's a lot of physical exertion just bringing the table down and putting it back up and moving the gantry across the table to see the flag."

Jennifer Jones turns a crank to re-position the gantry

When staff enters the chamber, they even have to protect the flag from themselves. "As human beings, we constantly shed skin cells and hair and leave traces of our DNA everywhere, otherwise CSI would be out of business," says Suzanne. "So what we want to do is not leave that behind in the chamber. When we look at how insect infestations start in museums, a lot of times they start when a new food source is introduced to an area. We don't want to leave skin cells and hair cells which could provide nutrients to insects. When they run out of that, they'll start eating the flag."

"We also don't want to bring in mold spores, so we always cover the garments we've worn outside because there are so many molds in in the D.C. area, being such a humid and swampy environment," says Suzanne. "We're also not bringing wools and things into the room because the likelihood of bringing in a pest. We cover our shoes because you bring in an enormous amount of dirt and unknown materials when you use the shoes you've worn outside."

Inspecting the flag in detail

As we were nearing the end of our interview, I was curious whether Suzanne had ever planned on working with such an important artifact. Did she ever think her career would go in the direction it has? "I always loved textiles, so that's not a surprise to me. Flags? That wasn't the first thing on my agenda," she admits. "I started out with furniture and costumes, and ended up with flags."

"I have to say that, having spent 20 years doing flags, I find them very fascinating artifacts," she says. "I also find them to be so intimately involved with stories of people. Every flag seems to have a story behind it. The people that cared for it, the people that fought for it, what happened to it after the battles: not every textile has that kind of story. Samplers might have the name of the little girl that made it, where she studied; but you don't know much else about her life. The battle flags all have this history that continues up to the present day."

This video on the flag's conservation from the Smithsonian Channel is also available for viewing on YouTube.

This post is one of a series celebrating the Star-Spangled Banner's 200th anniversary. This summer, the museum will be hosing Anthem for America, a global event celebrating the flag, the song, and their shared history. If you wish to register for the festivities, or just want more information, visit the site. Peter Olson is an intern in the New Media department.