Photographic Collections: Salvaging Water Damage
Collections can suffer water damage for many reasons, from leaking pipes to flooding rivers, with the quantity of water and its cleanliness differing greatly from one case to another. Water damage has a major impact on photographic collections, which are highly sensitive to humidity.
During the first few hours after water infiltration, the relative humidity rate will be high, possibly even reaching 100%. This will cause photographs printed on paper to warp and image layers to swell and adhere to adjacent materials. Mold may form within 48 hours. These microscopic fungi will feed on organic material found in photographs, especially gelatin. As a result, collections affected by water damage are at high risk of suffering losses or even total destruction — as image layers dissolve, mold develops, and photographs are separated from their mounts.
The goal of a salvage operation is to save a collection while preventing any further damage that could be caused by inappropriate action. The process involves several steps: assessing the situation, planning and organizing the operation, salvaging the damaged photographs, and reviewing the results.
Assessing the Situation
In the case of a large-scale disaster, for the safety of those carrying out the salvage operation, it’s essential to wait until security personnel give permission to enter the building. Following a major flood, the building structure and/or electrical system could be damaged. In some cases, the floodwaters may also be contaminated with bacteria or chemicals.
Once access to the site is allowed, the first step is to document the situation carefully with notes and photographs. This will help to inform decision-making about what measures should be taken. It is also useful for insurance claims.
It is necessary to identify the type and quantity of damaged photographs in order to define your salvage priorities. Some photographic materials are extremely sensitive to humidity and immersion in water, which means they should be dealt with first. In general, photographs which are no longer in their original condition are more vulnerable than those still in good condition. Examples include prints previously affected by mold and nitrate, or cellulose acetate film that has already begun degrading.
It’s vital to call a conservator as soon as damage has been identified, to prevent it becoming worse. However, while speedy intervention is important, it should not be at the expense of preparing an appropriate plan or taking adequate precautions. The choice of salvage plan depends on the nature of the collection, including the photographic processes involved, the quantity of photos affected, and their value to the collection. It also depends on what resources — space, personnel, materials — are available. It’s essential to establish a viable plan based on the means at your disposal in order to avoid potential further losses or damages due to disorganized, delayed, or overly aggressive salvage activities.
Organizing the Salvage Operation
The person in charge of the operation must be experienced and understand how environmental conditions impact waterlogged items. He or she must work with other personnel who possess complementary skills, including collections managers (who know the material best), conservators (who can train staff in handling and restoring waterlogged items), security personnel, civil engineers, electricians, and plumbers. To avoid confusion, it’s important to define the role of each person involved and appoint someone to supervise each aspect of the salvage operation.
First, establish a dedicated team to set up space and access routes for clearing out the affected areas, while also ensuring the security of collections, whether damaged or not. In conjunction with this activity, the environmental conditions need to be managed. To avoid the formation of mold, it is important to decrease temperature and relative humidity quickly in flooded areas and to ventilate the space properly to prevent the air from stagnating. However, it is also critical to contain the air circulation to contaminated areas to avoid the spread of spores.
At the same time, a second group should organize the teams, establish spaces for salvage in a non-humid area, and gather the necessary materials.
Once the spaces have been secured, photographs may be sorted into different groups according to the salvage process that will be used. They should be divided into three categories: those which will be air-dried, those which need to be dismounted and then air-dried, and those which will be frozen.
The team in charge of this activity must also document the operation and location of each item. Since the collection’s classification system will be disrupted by the salvage operation, it is crucial to identify the location of each article so that the collection can be reorganized once the process is complete.
Finally, the teams responsible for dealing with the collection should take care of transporting items from flooded areas to salvage areas and then carry out the salvage procedure itself. The goal is to save as much of the collection as possible in conditions which will minimize any subsequent restoration costs.
The Salvage Process
Air-drying is the most common salvage method for photographs. However, this requires a lot of time, space, and resources. Depending on the number of damaged photographs and the resources available, it may not be possible to dry everything within 48 hours, which is the cut-off point for avoiding the formation of mold. In this case, freezing photographs is recommended to buy time for organizing the salvage process. Note that some types of photographs cannot be frozen due to the risk of irreparable damage; these should be given priority when it comes to air-drying (see table next page).
Water-logged photographs are extremely fragile, so it’s essential to handle them with the utmost care, using containers or rigid supports, to prevent tears. Under no circumstances should the image layer be touched.
Photographs should be removed from their protective covers before cleaning, drying, or freezing. Make sure that the item and the information indicated on its container do not become separated.
Cleaning: When a collection is contaminated by dirty water, it’s preferable that you clean the photographs in cold, clean water before drying or freezing them; otherwise, mud or debris may permeate the material. Cleaning is a complex and delicate process that cannot be used for all types of photographs. It should be performed by personnel with appropriate training.
Air-drying: This involves placing photographs, image layer facing up, on a rack or absorbent material, such as blotting paper, paper napkins, or blank newsprint, which should be replaced after sufficient moisture has been absorbed. Frame-mounted works must be removed from their frames. If a photograph is stuck to the glass of the frame, do not try to peel it off and instead leave it to dry while still adhered to the glass. Separate piles of photographs if possible.
Freezing: Photographs should be placed inside Ziploc®-type polyethylene bags with a non-adhesive divider (wax or parchment paper) between each one. The bags may be collected in containers and then transported in a refrigerated truck to the location where they will be frozen.
Freezing water-damaged collections will give you more time to prepare for air-drying, allowing you to wait until the necessary material and human resources are available. Frozen photographs should be thawed in small batches to ensure that they dry out completely within 48 hours.
Once the salvage operation is complete, it will be possible to determine what percentage of the collection has been affected and to estimate your restoration needs, in order to file an insurance claim. This step also allows you to review the operation and identify areas where the process could be improved in the event of future water damage. The findings should be summarized in a written report so that there will be a record of the event in the collection’s history.
Every salvage operation is unique. There is no universal approach that fits all situations — organizing the salvage process depends on the cause and extent of the damage, the nature of the collections affected by it, and the resources at your disposal.
The initial assessment of the situation is crucial, since it makes it possible to develop an action plan suited to the circumstances. Timely, careful intervention will enable you to prevent the formation of mold and limit damage to the collection. A final review should not be overlooked, as it provides the opportunity to learn and be better prepared in the future.
Prevention remains the best way to limit damage. Reduce the risk of water damage as much as possible by preparing an emergency plan along with an organizational chart, acquiring materials that you will need in the event of a salvage operation, labelling photos according to the type of photographic process used, and selecting packaging materials that will protect the collection from humidity.
This museological report has been made possible through funding from the Government of Canada. This report was also published in Muse Magazine, March/April issue, 2018.