Preservation Guidelines
Preservation techniques by which to look after your collections
How to Preserve your Collections
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Inspect collections and remove any rapidly decaying nitrates, plastics, rubber, and urethanes that may contaminate neighbouring materials. Isolate newsprint and other highly acidic materials by storing them separately.
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House stamp collections in PET mounts on conservation quality album pages. If this process is not economically feasible, then just replace all PVC and deteriorated stamp mounts and pages with alkaline buffered and chemically inert archival-grade stock-cards and albums which you can buy from archival suppliers.
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Store philatelic covers in PET pockets/sheaths/sleeves. These will not only support structurally weakend covers, but will facilitate handling, prevent contamination and protect covers from their external environment.
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Store documents in good condition in group folders. Translucent acid-free tissue or other sorbents like dye-safe cotton fabrics, can be used to wrap and interleaving larger items and objects. This will prevent acid migration from neighbouring materials and facilitate safe handling and transportation.
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Place inert and safely housed covers and stamps into conservation quality boxes, or at least air-tight and waterproof boxes to buffer collections against environmental conditions, whilst facilitating storage and safe transportation.
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Choose the location for your collection carefully, Bear in mind the need for a stable environment. Avoid uninsulated attics, damp basements, over-drying central heating systems, outside walls and draughty windows.
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Store boxes levelly and securely on shelves and in plan cabinets. Line off-gassing wooden shelves with alkaline buffered paper or card.
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Oversized objects should be stored flat whenever possible, not rolled or folded. They are best kept in the drawers of flat files (map cases), made of anodized aluminum or powder-coated steel.
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Monitor the condition of philatelic collections after providing effective storage. Regular inspections should be carried out to check for signs of damage, or developing problems such as the possible formation of condensation within mylar sheaths.
See below for further information about how best to preserve your collections
Safe Plastics
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PET or polyester (trade names Mylar© & Melinex©). The most inert, stable and clear plastic on the market. It Lasts hundreds of years, but is the most expensive. The PET Hagner© stamp stock sheet system, for example, are excellent, they block UV light and they repel moisture.
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PP or polypropylene. Chemically inert, lasts quite well and is much cheaper than PET. It is not as clear. Copy-safe sleeves are usually made from PP.
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PE or polyethylene terephthalate. The cheapest option. It is still inert, quite long lasting, but discolours and shows reduced mechanical properties in the presence of UV light. Zip-lock bags are usually made of polyethylene.
Correct storage is paramount to longevity of any philatelic collection, and the easiest way to prevent active deterioration. The choice of materials for storage and exhibition is critical. It is vital that collectors replace their commercial acidic album pages and stock books with pH neutral enclosures.
Safe Paper & Boards
Album pages should be 'lignin free' to comply to ISO 9706 standard for permanent paper. The term 'acid-free' is often misimplied, and does not guarantee that a paper will be inert or long-lasting.
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Wash hands before handling.
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Handle items as little and as carefully as possible, preferably using flat-headed tweezers.
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Keep all drinks and other potentially destructuve items well away.
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Store covers and stamps in archival enclosures. Transparent enclosures will facilitate object viewing and handling.
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Ensure the material is sufficiently supported and protected when being handled. Archival card placed within an enclosure will provide support for weakened materials.
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Ensure sufficient support when transporting materials, by using secure storage containers and transportation mechanisms (trolleys etc.).
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Surrogate copies of fragile or frequently used documents can sometimes be substituted for the originals for display.
When handling philatelic materials you should:
Relative Humidity
An optimal RH of 45-55% is maintained in museums, however in a domestic setting this may not be possible. These simple and inexpensive household measures can be used to keep the RH below 60%:
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Select a dry and well insulated storage environment.
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Use humidistatic controlled heating and dehumidifiers
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Ensure passive microenvirments by checking display cases and storage cabinets are air tight. Store buffers such as packets of silica gel in with collections if required.
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Interspersedly check RH with a datalogger. These are commercially available and relatively inexpensive.
Temperature
Philatelic Collections should be stored at a temperature under 18°C. To achieve this at home:
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Select a storage environment with reliable walls, roof, windows, and doors, have good insulation, and preferably high mass walls.
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Ensure that direct sunlight, and other sources of temperature do not directly strike collections.
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Control temperatures can be monitored using a datalogger.
Ventilation
Continual ventilation using 99.97% efficiency filters at 0.6 microns is advised for archives, to impede potential disfigurements from abrasive particulates or gaseous pollutant contaminants.
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Select a storage location that is well insulated and not surrounded by sources of airborne pollutants (kitchens, workshop, parking lot, smoking & windy areas etc.)
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Do not carry out dust generating activities close to the collection.
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Block the infiltration of pollutants into collections by using air-tight, or air-filtered enclosures.
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Prevent the deposition of particulates using good storage.
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Use sorbents such as gas sorbents, or sorbent tissue wrapping when storing collections
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If possible insert an HVAC system, with efficient gas and particle filters to recycle and filter air-flow.
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Never heat a damp room without adequate ventilation as this may promote the growth of fungus.
The best lighting conditions to keep your collection in is complete darkness. However clearly this prevent viewing. As such an optimum light level of 50-55 Lux and standard limit of 75 micrrowatts/lumen (µW/l) is advised, to reduce possibility of fading and embrittlement. This is perfectly acheivable following the steps below:
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Illuminate the object using only incandescent bulbs or UV filtered light sources. Self-adhesive UV filter films, which can be used on windows, fluorescent tubes and cases, are commercially available and can be cut and stuck with little to no optical change. Blinds and curtains can act as a UV buffer.
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Items should not be exposed to light sources unnecessarily, or for indefinite periods of time.
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Framed items should not be placed opposite windows to avoid direct sunlight, and UV filtering glass should be used for framing.
Ideal pest control systems are passive, preventive and non-toxic. The initial step to take to achieve this is preventing infestation in the first place. This can be achieved simply by:
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Mitigating the environment that is supporting them. Infestation is unlikely to occur if bookshelves and books are kept clean, surrounding floors and carpets vacuumed regularly, and food and drink are not allowed in the area. This is safer and often far more effective than using poisons.
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Denying pests entry and impede mobility: This can be achieved by finding potential pest entry locations and then blocking them up (sealing cracks and cavity areas etc.)
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Having quick response times: Extended idleness will just allow the pest infestation to continue, encouraging deterioration.
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Prevent contamination by carefully checking for insects or eggs before bringing newly acquired items into the storage space.
If clear evidence of infestation is discovered, the following action should be taken:
Insects
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Isolate infested material from non-infested material.
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Brush book gutters carefully, page by page, to remove hidden eggs. Remove and brush book jackets and plastic covers.
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Move or dismantle shelves and carefully dust and vacuum the site, including under rugs and carpets.
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Freezing infested material set at or below -20°C (-3° F) can kill insects after ~3-4 days. All items must be in plastic bags to prevent water damage. This is not a routine treatment.
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Lay down pest traps at sites of entrance and damage. Monitor, inspect and replace.
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If the infestation persists a professional pest control company should be contacted.
Rodents
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Disturb rodent habitats by tidying and cleaning the infested area. If conditions no longer suit them, rats and mice will simply leave in search of a more appealing environment. If this does not happen, then traps and poisons can be used to kill them.
