The presence of mould is something that many archive collections have in common. Composed of organic materials, including paper, parchment, leather and some adhesives, they are vulnerable to outbreaks of mould growth when stored in unsuitable environmental conditions.
It is important to be aware that mould-affected collections present two significant risks: Firstly, to the condition of objects – mould can weaken the surface it grows on, making it fragile and vulnerable to further damage; text can be obscured; areas can become detached and lost; and handling can range from difficult to impossible. Secondly, to the health of those accessing it – mould can cause acute allergic reactions and the effects of exposure are cumulative. As such, ensuring that preservation and safe access are balanced is essential.
An outbreak can be resource-intensive to remediate, so the first step to managing mould is by employing a strategy of prevention. Exploring the following measures will help to identify risks and plan for a response.
Understand your environment
Is the environment monitored?
Employing a full environmental monitoring system or using standalone data loggers to collect information on temperature and relative humidity can build a picture of how the space performs, identify locations and periods of elevated risk, and can evidence the need for change.
Where is the collection stored?
Adapted or repurposed spaces can suffer from unforeseen problems with environment. Basements, areas with exterior walls, or spaces with high air infiltration rates can experience the elevated humidity which promotes mould growth.
What condition is the storage space in?
Is it well-maintained, or does it require improvements? If so, is there an active programme of building improvements which will mitigate the risk of damage to the collection?
Is there an HVAC (Heating, Ventilation and Air Conditioning) system?
Does the space have functioning heating, ventilation or air conditioning equipment that can help to ensure good environmental conditions can be achieved (i.e., through the use of an HVAC system, or dehumidifiers)?
Is the collection housed?
The use of good-quality primary housings, such as archival boxes, can provide a buffer against environmental conditions and can also reduce the risk of cross-contamination between affected items.
Be prepared
Know your collection
Where possible, survey the collection. Record information on condition, materiality and evidence of previous mould damage. Maintain accessible records of the same.
Monitor
To pre-empt outbreaks, make regular inspections of material susceptible to, or known to have experienced mould growth in the past. Prioritise locations and times of the year when risk is increased (such as shelving against external walls, and mid-summer). Be aware that inactive mould may re-grow or become food for other mould.
Employ mitigation strategies
Personal Protective Equipment (PPE)
Whether active or inactive, when handling mould-affected material PPE should be used. This should include disposable nitrile gloves and FFP3 particle masks. Disposable clothing protection, such as aprons and sleeve protectors can also be employed.
Good hand hygiene
Before changing tasks or taking a break from handling mould-affected material, remove gloves and wash hands with hot water and soap to reduce personal risk and avoid cross-contamination.
Training
Ensure staff are trained in the correct use and maintenance of PPE, as well as in the safe handling of mould-affected material.
Control measures
Prevent cross-contamination to other areas of the collection by restricting movement of mould-affected material. Where possible, set up dedicated areas for viewing and remediation; use separate materials and equipment for use with mould-affected material; dispose of contaminated PPE and other materials in separate waste streams.