Earlier this month, C2C partnered with Iredell Museums to host a Mold Recovery Service Learning event at the institution’s Gregory Creek Homestead site in Statesville. Months ago, Director Debbie Newby discovered mold growing in a building used to store overflow accessions. Remember that mold grows when the relative humidity is above 65% for more than 36 hours. The flood-prone masonry building traps moisture and Iredell staff recognized the need to relocate collections objects. They reorganized areas in a climate-controlled collections storage building to accommodate salvaged objects. However, they needed help learning how to assess whether mold is active or inactive and what steps to take to clean inactive mold from artifacts. C2C organized a staff training event and then invited others from NC’s cultural heritage institutions to join in to share knowledge on mold prevention and practice recovery techniques, such as vacuuming and wiping with rubbing alcohol.
We did not expect many folks to take advantage of the service learning opportunity, since mold poses a health risk, especially to those with previous respiratory problems. But we had seriously underestimated the generosity of our NC cultural resources community, and an additional 14 people came from 7 regional institutions to work with C2C and Iredell Museums’ staff. A special shout out to Davidson College Library for donating 6 staff members to the cause!
Personal protective equipment is critical when working with mold and working outside is safer, when possible. C2C provided N95 particle masks, nitrile gloves, and aprons for all participants. In more extreme situations, safety goggles and tyvek suits may be necessary.
Our treatment consisted of both dry cleaning and wet cleaning for most objects. See a previous guest post on our blog for further instruction about cleaning moldy books. For dry cleaning, brush the object in the direction of the vacuum nozzle. A nylon screen cover prevents sucking tiny pieces and parts into the vacuum. Plastic baggies are useful to have on hand to collect any loose pieces that dry cleaning dislodges. Necessary supplies include:
- natural bristle brushes
- vacuum (HEPA filter needed for indoor work)
- soot sponges
- groom/ stick paper cleaner or absorbene
- microfiber cloth
- rubbing alcohol
- paper towels
There are several useful mold recovery resources available online:
- The national Connecting to Collections organization produced a free webinar on mold recovery. View the archived version here.
- The Conservation Center for Art and Historic Artifacts has posted guidelines for managing a mold invasion. Upload available here.
- Information from the Canadian Conservation Institute offers more information here.
- It’s a useful reminder that not all white growth on artifacts is mold. Metal corrosion can be white. Anything with fat content, esp. dressed leather, is prone to fatty bloom as it ages. A good resource with more information and identification help is the “What’s That White Stuff?” website from Alaska State Museum conservators.
For most finished wood and metal there’s an additional mold recovery and prevention step you can take after the dry cleaning and wet cleaning steps. Microcrystalline wax—we use Renaissance wax— contains mineral spirits, which is another spore-killing and tarnish-reducing solvent, and works to even out finishes that mold or corrosion has left spotty. It’s also a thin coating on the object to deter mold spores from settling.
Several of our participants had previous experience working with various mold recovery products. Here are two they recommend:
- Davidson College Library uses Betco BTB Instant Mildrew Remover & Cleaner to clean areas up before painting.
- One of our participants is a building engineer and consultant who also works with the Burke County Museum. He suggests an affordable mold test kit. For $169 you can test an area, submit the results, and receive professional lab reports.
What strategies can you share for preventing and/or recovering from a collections mold attack?
Posted on November 18, 2014, in Uncategorized and tagged Davidson College Library, Gregory Creek Homestead, hepa filter vacuum, Iredell Museums, Renaissance wax. Bookmark the permalink. Leave a comment.