Category Archives: cleaning

Polk Kitchen Fire

This weekend the James K. Polk State Historic Site will celebrate the reopening of its visitor center as well as the 11th President’s birthday. The building’s exterior and interior have been fixed up, along with updated exhibits about Polk, who was born on November 2nd 1795 in Pineville, an NC backcounty town not far from Charlotte.

Further renovations will be necessary to the Site’s kitchen building as a result of a disaster at the site last month. On October 9th fire broke out in the roof. According to Site Manager, Scott Warren, the building dates to circa 1800, but had been moved to the site in the 1960s. Staff had outfitted the interior with period artifacts to use in kitchen demonstrations. Unfortunately, after putting out the hearth fire once the demonstration ended, a sparking ember got caught within the chimney and the old wood continued to burn inside, until a fire broke out at the attic level after staff had left the site. Firefighters responded quickly and were able to salvage the building’s lower floor. This fire, however, presented a new artifact recovery challenge–fire fighters put out the fire with suppression foam. Foam is a relatively new product/ technique in firefighting and may require an altered process for artifact recovey. In the Polk instance, however, firefighters removed all artifacts from the kitchen and attic before applying foam.

PolkFireIn this screen shot from the local news coverage, the fire suppression foam is visible coating the floor of the kitchen, after firefighters had evacuated the artifacts from the building.

But what if the foam had contact with artifacts? In addition to soot and ash damage, those involved in recovery would have to consider the effects of foam residue. It turns out that conservator-recommended recovery procedures are similar, with vacuuming first and then wet cleaning with water and a mild detergent. Soot sponging is the recommended 2nd step after vacuuming, but may not be as applicable with foam residues. When foam is involved, rinsing may be a necessary step for most artifacts, rather than a last resort, as conservators recommend in other cases.

Experts from the Bureau of Land Management offer the following advice:

Foams may hasten rusting on metal surfaces by removing protective coatings and may cause wood to flake due to swelling and contracting…[the] retardant should be washed off important structures as soon as possible. Pre-soaking, then hand-brushing with water and a mild detergent may work for sandstone or painted wood. Metals and glass may be wiped with water and a mild detergent.

Fire suppression foams are proprietary and their chemical compositions may differ. Historic Sites Curator Martha Battle Jackson was concerned about chemical residues the foam may have left behind and ways it could react with cleaning solutions staff would use in the building after the fire. Firefighters provided her with the manufacturers’ safety data sheet (MSDS) for the product they used, ThunderStorm® FC-601A 1% or 3% AR-AFFF concentrate. (download available here)

Suppression foams work by creating a film or membrane to act as a barrier, preventing the release of fuel vapor. Regardless of the fuel type, the foam cover excludes oxygen and drains the liquid composition of the membrane. Additionally, the water content of the foam produces a cooling effect. The ThunderStorm® product promises to be biodegradable and low in toxicity–reassuring information for the Polk recovery efforts.

Our hats are off to Pineville firefighters and Historic Sites’ staff for their quick and effective artifact salvage, as well as introducing us to innovations in firefighting technology. Have you encountered fire suppression foams before? Do you have any advice to share about artifact recovery after its use?


Fire Recovery: Simple Triage and Rapid Treatment

For disaster recovery workshops, we’re following the lead of emergency responders by promoting START: simple triage and rapid treatment. However, while those professionals are focusing on human victims, our participants deal only with the much less urgent and less significant needs of artifacts.

Triagetag2Upon relocating the artifacts to a safe work area (using as limited and safe handling procedures as possible), the next step in recovering artifacts from a fire is triage. For our last workshop, we modified emergency responders’ START tags for artifacts.

  • Green: Undamaged artifacts have usually been housed securely enough to protect them from soot. After careful inspection, these can be rehoused in clean containers for a return to storage with no treatment necessary.
  • Yellow: these objects require simple treatment techniques before they can be packed up for long-term storage.

Conservators recommend a strict progressive cleaning procedure that begins with vacuuming and moves to soot sponging and then to wet-cleaning, if necessary and safe for the material. These techniques enacted quickly after the fire will guarantee the highest degree of soot removal for most objects.

  1. Air dry if necessary. Find a shady place if outside or use electric fans to promote air flow inside.
  2. Vacuum: conservators recommend vacuuming in place before relocating the object, but after a fire it is more likely that the contents of a burned structure will be removed before artifact recovery can begin. Brushes should not be used in the soot vacuuming process. If a nylon screen or old panty hose is available, it can be used to cover the nozzle only and should not be pressed against the object. If not, place a thumb on the edge of the nozzle as a bumper to space it a short distance from the object.
  3. Soot sponge: remember to use a dabbing motion, rather than rubbing, which will may grind the tiny soot particles into the object.
  4. Wet cleaning:
  • Ethanol wipe/ dab for metals, also useful on glass and high-fired ceramics
  • Squirt bottle rinse with weak detergent solution (select one with low levels of dyes and perfumes such as Palmolive free and clear.)
  • Blot with damp cotton swabs or rags
  • Avoid immersion but this may be necessary as a last resort

In addition to Heritage Preservation’s brief video, click here for the best professional guidelines we’ve found so far that are specific to soot and ash.

  • Red: objects may be packed for relocation to a conservation studio right away, or they may go through the simple treatment techniques outlined above before going into this category.
  • Black: objects that seem too damaged to recover or not enough of an institutional priority to warrant conservation costs go into the “morgue”—a holding area to await the formal deaccession process before disposal.

We’re working though this START system for artifacts in workshops and so far it’s been a useful approach. We plan to train our Cultural Resources Emergency Response Team (CREST) in its use for future actual disaster recoveries and will practice it again at our next fire recovery workshop in Greensboro.


Leaving a Mark

In honor of May as Preservation Month, this post is about a preservation issue inside a building that is iconic for all of North Carolina as well as its capital city.  Since its completion in 1840 many visitors to the Old State Capitol Building in Raleigh have left their marks. The large hand-cut stone blocks bear the chisel indentations of various stone cutters; the worn stone steps attest to many footfalls and heavy loads dragged upwards; and wooden banisters in the house and senate chambers boast carvings of names/ initials and dates. Is it a sense of the structure’s significance that has compelled some of those passing through to carve their names into the wood? These marks of creation, use, and commemoration (however subversive) are visible to all who visit the Old Sate Capitol for one of its free tours.


stairway to storage

stairway to storage

Recently I took advantage of an opportunity for NC Department of Cultural Resources staff to take a behind-the-scenes tour of the building. We snuck peeks at staff offices, attic storage areas, and views near the rotunda. The marks individuals had left behind continued, and perhaps became even more pronounced, as we climbed and pressed our way into non-public areas. This wall (left) near a roof access door exhibits over a hundred years’ worth of visitors proclaiming “I was here!” Earlier marks from the 1900s or so have been carved into the wood, whereas modern graffiti artists chose markers to commemorate their visits.

fingerprintselectricianGraffitiAdditionally, several of the more hidden corridors bear the marks of hands which have accomplished the difficult and often dangerous work of building maintenance duties. These marks on the right are from electricians who have squeezed into tight spaces and balanced themselves on ledges to change light bulbs around the senate chamber rotunda.

When do preservationists view marks like fingerprints and graffiti as defacement in need of correction and when do we view them as interesting testaments to a building’s (or object’s) use and significance? This is a question object conservators must ask themselves before each treatment, and sometimes the answer is different. Cleaning is irreversible and permanently strips away evidence of human interaction with the material. The Old State Capital staff has taken two different approaches to this quandary. For some of the wooden railings bearing carved letters and numbers from visitors (dating from the building’s period of use, 1840-1963), the marks remain. For others, staff has in-filled the carvings and painted over the rails.

Which approach (or combination) has your site taken?

–Adrienne Berney, C2C Collections Care Trainer

Fire Recovery Practice

EricRogersOur Fire Recovery Workshop last week at the Buncombe County Public Safety Training Center is now behind us. We enjoyed beautiful, crisp fall weather in the mountains and a wonderful new facility. A shout out to the facility’s Director and fire fighter, Eric Rogers, for accommodating our unusual needs so well! This was our team’s 3rd and largest fire recovery workshop so far and we are planning at least 3 more of this type of training.

burnScene2One lesson we learned this time from our participants is that we need to provided clearer guidelines on how to recover artifacts before sending our group out to “just do it!”. Heritage Preservation offers a good start with this video, which our group was able to review beforehand, but its recommendations are limited to vacuuming and soot sponging. A couple of points to remember about these materials:

  • Vacuum objects in place before moving, if possible.
  • Do not unroll textiles or open books before vacuuming.
  • The vacuum should not be in direct contact with the artifact. Hold the nozzle with a thumb on its edge to prevent touching the artifact.
  • If possible, cover the nozzle with a flexible nylon screen, or even an old piece of pantyhose, to prevent sucking any loose bits of the artifact up, while vacuuming soot particles.
  • Variable suction is a helpful feature in recovery. On our windy day, the shop vac we used tended to pull textile items too much.
  • DavidGoist&SootSpongeOur consulting conservator, David Goist, cautioned our group to examine surface materials carefully before deciding to soot sponge. The pressure of applying a soot sponge might grind soot particles into some matte surfaces.
  • The name “sponge” is somewhat misleading for this material. Although it looks like a sponge, it should not be used to rub. A light dab will trap the soot particles on one face of the rubber cube. Cutting the dirty face off with scissors exposes a clean surface for more trapping.

The soot sponging process can also help identify patterns in soot damage. On Rogers’ suggestion, we placed one object, a carousel horse, in a room on its own, separated from the controlled burn areas. The recovery team found by sponging that soot only collected on top surfaces of the piece.

Although Heritage Preservation’s guidelines urge caution against rinsing anything sooty, Goist instructed the group that objects like glass and high-fired ceramics can usually be rinsed. Silver flatware may also be rinsed and then wiped with a cotton rag dampened with ethanol. Participants had success with these recovery techniques for the “artifacts” they recovered from the dining table setting in the mock museum.

Next week’s post will address the fate of the plastic storage materials we used in the controlled burn exercise.

Clarification: CREST – not just a toothpaste & *ACREN – not just a city in Ohio


While in Western North Carolina a few years ago, I heard an old Mountain idiom that went: “Yep – those directions was just about as clear as mud.”  I think that is what is happening with the new disaster recovery organization structure here at C2C.  So I am going to try to clear up the mud hole in regards to the structure and purpose of CREST and the related sub groups for emergency salvage of artifacts in the event of a natural or man-made disaster.

CRESTCultural Resources Emergency Support Team

Breaking down the letters of CREST, acknowledges that the group originates here at the NCDCR.  The purpose of forming a statewide team is to be able to respond to any library, museum or historic site in North Carolina that has a disaster or crisis.  CREST participants would provide the manpower and the supplies to begin immediate salvage and recovery of artifacts and collections at the site.  It is an “all hands on deck” for the people who are signed up as part of the CREST team to respond as quickly as possible.  Here in Raleigh, we will maintain a cache of recovery supplies that might be needed. Supplies are stored here in large tubs ready and waiting for a call to respond. Examples of the supplies are soot sponges, wax and parchment paper, tarps, Tyvek tags and pens, drying racks for small and medium sized textiles, rope, close pins, clean water, fans, extension cords and numerous other items we can stockpile.  Should a call come to Raleigh of a crisis, we will deploy CREST persons with the tubs of supplies to that facility.  All CREST team members receive an individual “Go-Pack” of personal safety equipment and immediate triage supplies to get started.  Items in the go-pack include a safety helmet and vest, masks, gloves, flashlight, simple tools, and other items.  (See photo)

On the local level, there are regional groups that support the CREST team. The letters of the regional groups stand for Area Cultural Resource Emergency Network.  So far, there are three groups. They are in the Triangle, Mountain and Piedmont sections of North Carolina. Add the first letter of the region to *ACREN and you have TACREN, MACREN, and PACREN.  These regional groups are the first responders to their regional area that is experiencing the disaster. The CREST team will arrive as quickly as possible with trained personal and specialized supplies as backup.

Both CREST and *ACREN members have been trained in personal safety, recovery of artifacts and organizational procedures in a disaster.  Workshops and classes emphasize an immediate triage and joint effort to stabilize the condition of the collection.  The goal of quick response to a disaster is to prevent further long-term damages until the items are evaluated for future conservation and restoration by professionals.

Anyone who is trained in artifact recovery can be on either the regional *ACREN group or the statewide CREST team.  Actually, a participant can be on both because the training is the same.  The differences lie in the ability to respond.  A CREST member must be willing to respond anywhere in North Carolina.  (And of course in their region as well.) However, a member of one of the *ACREN groups only responds to help their colleagues in their geographic area.

We are striving, through workshops and training to empower library, museum and historic site staff in all regions of the state.  There are dreams of a CACREN, (Costal) WACREN (Wilmington) and OBX-AREN. (Outer Banks)

If your area is interested, we will be more than happy to provide training, workshops and burn recovery to collections.  We would love to have a long list of *ACREN groups ready and prepared to assist each other.  Hopefully, this clears up the muddy mess to at least a watery mess.  Stay safe and continue updating the inventory list.

Lyn Triplett

Disaster Preparedness Coordinator


Raleigh, N.C.

Polishing Silver

Kathy Ruse of the Joel Lane House polishes a spoon during a C2C workshop in 2010.

Kathy Ruse of the Joel Lane House polishes a spoon during a 2010 C2C workshop.

Our first rule on polishing silver is to avoid it. Not because collection managers are lazy, but because each time we polish to remove tarnish, we rub away a microscopic layer of the material. Over time polishing can diminish and even deface the historical material. Most of us have seen incidences of this where the engraving on silver artifacts has become barely visible after many years of polishing. Silver plated objects can loose their shiny metal casings readily with polishing and reveal patches of copper or another base metal beneath.

Several storage materials can prevent tarnish by blocking sulfuric pollutants from coming in contact with the silver. 4 products are especially effective:

Still, even with methods to prevent tarnish, there are times when silver artifacts must be out on exhibit, outside of protective cases. Perhaps this is most common within historic house museums, where silver often gleams from table settings and sideboards. When polishing becomes necessary, collection stewards should use the gentlest methods and materials possible. In the past, our “Collection Care Basics” workshops have included practicing with silver plate utensils, and this activity has been one of the hands-on components participants have enjoyed. We have followed the directions outlined in the National Park Service’s Conserve O Gram on silver polishing. First wiping pieces down with cotton rags dampened with ethanol and then stirring a polish made from precipitated calcium carbonate mixed with distilled water to form a cream consistency. (Click here and scroll to page 3 for more complete instructions.) Other great online resources are two videos that the Nebraska State Historical Society’s GeraldR. Ford Conservation Center produced—one on polishing (solution varies slightly from the NPS recommendations) and another on applying microcrystalline wax as a protective coating.

Now, as our C2C project focuses more on disaster preparedness and recovery, our Basics workshop will concentrate more on storage methods as disaster damage mitigation. We will use the hands-on time previously spent on silver polishing to practice creating storage cradle mounts from ethafoam instead. We hope the online resources we have suggested, along with whatever personal guidance we can offer, will help you through the polishing process. NC metals conservator, Jane Bynon, is another local resource and is one of the few experts in the region who has the capability to lacquer objects–another tarnish-preventing option for silver on long-term display.

What methods for preventing and/or removing tarnish have been most successful for the collections under your care?

Cemetery Preservation

Thanks to Michele Patterson-McCabe, Grants Coordinator in the State Historic Preservation Office, for her contributions to this post.

The national holiday, Memorial Day, standardized an Appalachian tradition of honoring the dead with annual cemetery maintenance, floral headstone decoration, and often “dinner on the grounds.” Decoration Day varies slightly from community to community but is always in late spring through early summer. Folklorist Alan Jabbour and photographer Karen Singer Jabbour have traced this tradition to the early part of the nineteenth century and mapped its spread, as Appalachian families migrated further south and west. Click here for a summary of their recent book, Decoration Day in the Mountains.

One of the gravestones in Murfreesboro's Southall Cemetery

One of the gravestones in Murfreesboro’s Southall Cemetery

It is common for cultural heritage institutions to have stewardship responsibilities for cemeteries, either as a regular community service project or by virtue of property ownership. Two examples are the Murfreesboro Historical Association, which maintains Southall Cemetery, and the St. Paul Museum in Randleman, which operates in a former church with a cemetery behind.

St. Paul's in Randleman

St. Paul’s in Randleman

Is a regular “Decoration Day” part of your community’s traditions? If so, there are several helpful online resources to guide your maintenance efforts and warn against overly aggressive (and ultimately destructive) cleaning measures, such as pressure washing. Here are some top tips for gravestone cleaning.

  • A garden hose with a gentle soaking spray is appropriate for most cleaning.
  • A good cleaning brush (natural or nylon, not metal wire) will loosen dirt and clean crevices.
  • Do not use bleach. Although it may have an instant brightening effect, its chemicals will dissolve parts of the stone.
  • Do not yank plants out that may be growing out of the stones. Cut them near the stone and wait several days until they wither before pulling them out.
  • Scrape lichen off with a wooden or plastic scraper.
  • Avoid household soaps and acidic cleaners. Preservation experts recommend non-ionic cleaners available from janitorial supply companies and suggest a solution of one ounce non-ionic detergent to 5 gallons water. (Triton X is one possibility.)

For more practical advice on gravestone cleaning, click here and here. For a comprehensive guidebook on overall cemetery preservation, click here.

Several staff members in North Carolina’s State Historic Preservation Office have gained a great deal of expertise in cemetery preservation and are available to answer questions and give advice. Contact John Wood, Restoration Specialist in the SPHO’s Greenville office, or 252-830-6580 x 225.



Silver Care

silver epergne on a dining table at Historic Edenton's Cupola House

silver epergne on a dining table at Historic Edenton’s Cupola House

Silver should be polished as infrequently as possible. Of course, historic house managers want to avoid silver turning black, gold, or purple. Although frequent polishing may do more harm, significant tarnish will suggest a lack of collections stewardship. If silver objects must be exhibited, then staff should practice the gentlest possible polishing methods. Several materials are available to help block tarnish-inducing sulfides from silver artifacts in storage.

1. Rub gently with lint-free, white cotton knit rag dampened with ethanol (denatured alcohol). This will remove any old wax or oily build-up that may be on the piece and clean off some, if not most, of the tarnish. (It may then be possible to skip steps 2-3.)

2. Mix a thin paste of precipitated calcium carbonate and distilled water. The paste should be a cream consistency. Dip a rag in the solution and rub silver as gently as possible. A pointed tool may be necessary to work with incised borders and decoration. Gently rub crevices with a toothpick.

3. Wipe with a clean rag, moistened with distilled water. A moistened, rag-covered point may be necessary to wipe crevices free of polishing paste. It may be necessary to dip pieces in distilled water to rinse and then blot with dry rags.

4. If piece will be exhibited, use a natural hair brush or a dry cotton rag to apply a small amount of micro-crystalline paste wax onto the surface of the piece.

5. Quickly buff with a clean, dry rag. (Do not allow much time to elapse between steps 4 & 5.)

6. Consider lacquering as a conservation treatment for silver objects on permanent exhibition. Waxing should last about a year before tarnish re-appears; lacquering should last about 10 years. Remember, even the gentlest polishing materials and methods remove trace amounts of the artifact, which may add up to a noticeable loss over time. (For a list of metals conservators, click here.)

7. Make corrosion intercept film covers for silver on exhibit. Try wrapping hollowware and flatware with intercept during times the exhibit is closed to the public. This material will absorb tarnish-producing gases and need to be replaced when color turns black. This method should reduce the need for polishing. If silver is exhibited inside a case, 3M anti-tarnish strips contain activated charcoal pollutant traps that will adsorb sulfides and help protect the silver.

8. Store silver in boxes or drawers lined with Pacific silver cloth. Or create individual wraps or pouches. Intercept films and bags are also silver storage options.

If you are interested in practicing some of these silver care methods, join us for a collections care basics workshop in Greenville, NC on February 25th.

IPM Tools and Trials

As we’ve discussed here previously, monitoring for pests with sticky traps is an important routine for integrated pest management (IPM) in museums. Unfortunately, a great deal of damage may have already occurred by the time sticky traps show evidence of a heritage-eating pest population. Especially for moths, but in other pest species too, the larvae are the voracious heritage eaters. By the time you see an adult, there are probably numerous eggs lurking and larvae feeding somewhere nearby in the dark.

If adult moths are visible, as they have been in our team’s office cluster, try to pinpoint the area with the highest concentration. That can help you narrow down the source of the infestation. In our case, the preponderance of moths was on the ceiling of one office, so staff members began cleaning out everything in that space. Larvae were all over old NCECHO files in one particular file cabinet. NCSU’s Entomology Extension Service  identified our problem (via this photograph) as an Indian meal moth infestation. Despite the available descriptions of this species as eating grains and other food stuffs, the larvae in our office area thrived on old paper products, with no apparent food around.

Wanting to avoid pesticide sprays, we began a trapping/ killing campaign. This had already begun with our “splat!” swatter, and once we had a definite ID on the species, those in charge of our building could order the appropriate pheromone traps. Because our infestation was in file cabinets, rather than artifact storage, we used Allure traps that attract adult males. If you find an infestation in artifact storage, your problem requires urgent treatment and you should probably consider a newer kind of “moth suppression” trap that includes a female attractant. These are significantly more expensive, but killing female insects is a much more efficient way of treating a pest problem.

After one month of trapping, we replaced the pheromone trap and our need to swat has declined drastically. Though our pest problem persists, there’s hope for a moth-free future.

What IPM tools and methods have been most helpful in your institutions? Have you tried one or both kinds of pheromone traps?

Beware Carpet Beetles

One of the most common and damaging heritage eaters in your building is likely the varied carpet beetle. Close regular inspections of your storage and exhibit areas will often yield these insects. Adult beetles often emerge from the darkness that the larvae prefer and move into lit areas. At a glance they are about the size and shape of a small mouse dropping. A closer look reveals a brown spotted pattern and a flattened underside. Although it may be a relief to find that the particle is an insect rather than rodent feces, carpet beetle lavae can destroy a variety of materials in your collection. Wool, leather, horn, and feathers are all attractive as larval feeding sites.

There are two primary techniques to protect your vulnerable collection items.

  1. Vacuum! This process dislodges all stages of beetles and their leavings.
  2. Block! It may be helpful to seal up your building’s cracks and crevices, but it is unrealistic to believe that you’ll be able to block tiny pests in this way. Storage containers are a much more reliable preventative measure. If insect damage has been a problem at your institution, consider polypropylene boxes to store proteinaceous materials. Of course, vacuum before sealing in a storage container.

Luckily, there is an expanding set of free resources on the internet to help you identify heritage eaters and strategize solutions to protect your collection. Several years ago Alaskan Conservator Ellen Carrlee posted an illustrated discussion of heritage eaters and helpful Integrated Pest Management guidelines for small museums. Additionally,  contains an image library that can be a great resource to help you identify the heritage eaters at your site. The site also includes fact sheets to give you specific information about each type of pest. Click here for more about the varied carpet beetle.  NC State University also has an especially strong arthropod identification program and entomology extension service.

In contrast to the collection dangers they present, carpet beetles have a helpful role to play within institutions that collect bone specimens. Natural history museums, medical museums, and some anthropology museums can use these critters to their benefit in preparing bones for storage. See page 3 of the National Park Service’s Conserve O Gram on vertebrate collections. By efficiently eating away all tissue remnants, the beetles leave bone specimens clean and ready for perpetual preservation.

What other heritage eaters plague your collection? Which integrated pest management techniques have proven the most effective for your site?

Carpet beetle image from