We currently have two research projects on mould at Knole. The first is being carried out by students at The Courtauld Institute of Art. Below they provide us with an outline of their research:
Our project considers an 18 months environmental survey monitoring the daily and seasonal changes in temperature, humidity, light levels and airflow across a representational sample of the show rooms at Knole. The historic and listed building suffers from active mould damage which may be exacerbated by the uncontrolled environment with huge variations in temperature, humidity and light throughout the year. Mould damage is an on-going problem that has caused damage to paintings, textiles and furniture throughout the many rooms in Knole.
On-going to our environmental survey will be the sampling, culturing and identifying the of extant mould from the property. We aim to identify the currently active mould strains & their ideal living and growing conditions throughout the rooms being tested.
Petri dishes where mould has been cultured from the show rooms in agar jelly. Three petri dishes were placed at different locations in the Spangled Dressing Room, three in the Leicester Gallery and Billiard Room, two in the Venetian Ambassadors Bedroom, and one in the Brown Gallery.
A close up of some of the cultured mould!
Our intent is to use our data and environmental model to predict the efficacy of environmental controls and how these controls may inhibit or prevent the future growth of mould on the artworks in Knole. Our model will also facilitate making new recommendations to establish safer environmental control for the historically important and diverse collections. It is an exciting project that we are looking forward to completing.
Students here are using a cotton wool swab to take a sample of mould from the surface of a painting in the Billiard Room.
The students also took a sample of mould from the Billiard Table baize.
Here an impactor air sampling machine is being used to take air samples from each of the show rooms the students are researching.
Impactor air samplers use a solid or adhesive medium, such as agar, for particle collection. In a typical impactor sampler air is drawn into a sampling head by a pump or fan and accelerated, usually through a perforated plate (sieve samplers), or through a narrow slit (slit samplers). This produces laminar air flow onto the collection surface, often a standard agar plate or contact plate filled with a suitable agar medium.
The velocity of the air is determined by the diameter of the holes in sieve samplers and the width of the slit in slit samplers. When the air hits the collection surface it makes a tangential change of direction and any suspended particles are thrown out by inertia, impacting onto the collection surface. When the correct volume of air has been passed through the sampling head, the agar plate can be removed and incubated directly without further treatment. After incubation, counting the number of visible colonies gives a direct quantitative estimate of the number of colony forming units in the sampled air.
This information was taken from the following website: http://www.rapidmicrobiology.com/test-methods/Air-Samplers.php
Our second research project is being undertaken by Tess Evans as part of her Masters in Museum Studies with Leicester University. Her research project is investigating the use of a new biocide to remove mould from heritage objects and sites. Tess currently has a trial
underway on a mould affected wall in a servant’s corridor off the Leicester Gallery.
Here is the wall before treatment.17.4.13
A frame has been placed against the wall and Tess has cleaned each square with a different concentration and method of application of the biocide. The idea is to monitor its effectiveness and how quick the mould returns and Tess will return at regular intervals to assess this and take photographic records.
Area 3 being cleaned with an impregnated wipe.
The sectioned area after cleaning 17.4.13
One of spare Hanwell temperature and relative humidity monitors has been placed in the corridor next to the trial area so that Tess can use the data to assist her research. The monitor record an hourly average of the temperature and relative humidity 24 hours a day.
The same section on 3.6.13 with no mould growth evident! (sorry for the awful colour, my flash didn’t go off)
Area of wall with the frame removed to clearly show the cleaned area where no mould has regrown. 3.6.13
Thanks to Tess and the students from The Courtauld Institute of Art for the information on their projects.
Sarah, Lucy, Melinda, Zena and Emily