Stopping Mould Growth

Mould is one of the most difficult agents of decay to eliminate once it has a hold of textiles. Because it is so destructive, fairly drastic measures are sometimes used to deal with it. Careful use of ultraviolet light from sunlight is one such method that can be effectively employed to kill mould spores and prevent ongoing problems.

High relative humidity (RH) and poor air circulation are two of the main causes of mould on textiles. If the occurrence of mould on an object (i.e. musty smell) is suspected then simply airing it out and increasing the airflow around the object should help. If the object is clearly stained by mould, it is important to first stop the mould process to prevent further damage. For white ware this can be most easily done by either of the two techniques listed below.  For coloured materials, it is important to consult the conservation department at the state museum as there are specific issues relating to the colours in the fabric.

White wares can have mould growth significantly curtailed by simply airing out on a sunny day. By placing the item out in the sun (for about 1/2 hour each side in summer, 1 hour each side in winter) the combined effects of ultraviolet light, heat and dryness can very effectively kill the mould spores. It is so very important not to forget that the item is outside as there have been cases where textiles undergoing this treatment have been left outside overnight by accident! It may also be necessary to secure the textile to stop a gust of wind from moving it. While ultraviolet light is damaging to organic materials, this small exposure to light is considered less damaging than the continued exposure of the object to active mould spores.

Supposing that it is a wet and rainy winter, or that it is not possible or sensible to take the item outside, then lightly spraying the affected area with pure ethanol from a hand spray pack will kill mould. As before, this treatment is really only appropriate for white ware as the ethanol may cause dyes to bleed.

References and further reading:

Australian Institute for the Conservation of Cultural Material, ReCollections

Museums and Galleries NSW, Online Resources: Combatting mould, by Museum & Art Gallery of the Northern Territory