It has been a very wet summer season in New England, and we have felt its effects here at The Gables. The basement of the Nathaniel Hawthorne Birthplace flooded last month, which led to mold formation both in the basement and the first floor. Mold forms in wet, warm, humid conditions, particularly where there is little light and air flow. Mold spores spread via the air, making them very difficult to fully eradicate. It will grow on walls, textiles, wood, paper, leather – any organic material. In museums, relative humidity levels should always be kept below 65 percent, and temperatures at or below 68 degrees Fahrenheit to protect the collections and the structures. With all the warm, humid conditions we’ve experienced this summer, mold bloomed and spread with amazing speed.
We installed a powerful sump pump and industrial dehumidifier, and dried out the basement. The relative humidity and temperature levels are now back to recommended levels. The HVAC filter was changed to a MERV-16 rated version to remove very small particulates. Small fans were installed in some gallery spaces to increase air flow.
We found mold on many of the objects in the kitchen as well as Nathaniel Hawthorne’s sofa and Susanna Ingersoll’s chair. Mold remediation is an important process, but we are unable to use chemical mod removers on collection objects. The solution is UV rays in the form of sunlight.
On a dry, sunny day in September all of the affected objects were moved out of the birthplace and down to our seaside lawn. Staff wore M95 masks and gloves since mold can pose severe health issues for individuals. We left the objects in direct sunlight for about six hours, turning them halfway through to make sure both the front and back sides were treated. Once the UV rays had done their work, the furniture was carefully cleaned with a HEPA-filtered vacuum and staff again wore protective gear. With the right environmental conditions re-established in the building, we returned the collections pieces to their spots in the exhibit rooms. We are continuing to monitor for humidity and mold throughout the Birthplace and on the entire campus. Once mold is in your space, it is very hard to get rid of completely. We will manage this situation long-term.Tags: historic house museum, historic preservation, Salem, salem ma, support preservation, the house of the seven gables
This post was written by Holly Watson