Archives, Documents and Paper Storage
If your organisation stores paper documents, it’s vital to consider how seasonal humidity and temperature fluctuations can affect document preservation. Without proper climate control, ambient temperature can negatively affect and damage documents.
Damaging Effects of Humidity in Paper Storage
Many materials are more susceptible to moisture than they are to temperature. There is a direct correlation between high relative humidity (RH) and moisture damage to stored products, products like fiborous paper.
A large portion of Australia experiences high humidity in summer. When we measure humidity, we are talking about relative humidity (RH). In a nutshell RH refers to the amount of moisture in the air. The hotter the air, the more water it can contain.
Book and Archive Storage
Books, documents, and other archival material are hygroscopic, meaning they absorb and release moisture. The materials expand and contract depending on the temperature and relative humidity. The more environmental changes the documents experience, the more vulnerable they are to accelerated deterioration.
Paper Storage
Paper is a fibrous and naturally hygroscopic, therefore vulnerable to temperature and humidity changes. In an attempt to reach a balance with its surroundings, paper collects and releases moisture, which can affect its shape, dimensions, strength, and performance.
If the paper neither absorbs nor loses moisture, then it remains in its optimal state.
Controlling Humidity when Storing Paper and Other Moisture Sensitive Material
Sometimes indoor humidity is higher than it is outside. This increased indoor humidity can be caused by a variety of, or culmination of several factors. Poor ventilation, overworking AC with an inadequate outlet, walls or windows not properly sealed allowing moisture to invade.
Specialised climate conditions are required when storing organic materials. Humidity, temperature, and pollutants are important factors to consider when archiving.
When it comes to paper storage, maintaining a constant temperature and relative humidity level is important. However not having the ideal level is better than allowing the environmental conditions to vary and fluctuate.
Temperature and Humidity
The lower the temperature the longer your items will last, because cooler temperatures slow the rate of chemical decay and reduce insect activity. Keep the temperature below 22° C.
Keep the RH below 55% to prevent mould growth and reduce insect activity.
Avoid very low relative humidity because RH below 15% can cause brittleness.
It is commonly acknowledged by preservation experts, that inappropriate water vapour in the air is a real threat to the preservation of documents, artefacts, and relics. Once damaged, the items will never return to their former condition.
The ideal temperature for paper storage varies between 18° and 22° C and relative humidity (RH) should sit between 40 and 55%.
If we consider that relative humidity (RH) is generally quite high throughout Australia, in some cases reaching 65 to 80%RH, then relative humidity is an important consideration when storing hygroscopic and moisture sensitive material.
Other Storage Considerations
Dust free area
Good air circulation
Weightbearing floors
Tall ceilings
Air filtration system
Smoke detectors
Moisture detectors
Fire extinguisher
An area that is not under water pies
Shelves that are deep enough to lie documents flat
Shelves that are deep enough for the storage boxes
The area is carpet free
Storage Location
When choosing a storage location for archives, cardboard boxes and paper storage, avoid basements as these areas are more susceptible to water related damage and generally the temperature in these areas can be either higher or lower than the temperature within the rest of the location. Basements can also have poor ventilation.
The ideal storage space will be easy to clean and maintain, have sufficient space, and make retrieving documents easy.
The floors should be able to withstand shelves full of documents without causing structural damage. If the area has overhead water pipes, position the shelves so the pipes are over the aisles and not the shelves
Storage Handling
The best storage materials do not omit volatile organic compounds (VOC) and are acid free. Boxes are great for keeping documents dust free and out of the lights.
When labelling files use a pencil instead of a pen. Pens tend to fade and the ink can also bleed onto paper
Pollutants
Air quality is also an important factor for paper storage. It’s crucial to ensure proper ventilation with the storage area to prevent harmful compounds from building up. Harmful compounds such as dust, nitrogen oxide, ozone, formaldehyde, sulphur dioxide, volatile organic compounds and carbon monoxide.
A Well-Rounded Solution for Paper Storage
There is an easy solution that once set up, frees you from constantly monitoring your indoor climate. Many use heaters, however, this is costly and increases your energy consumption considerably. N.B. While heaters may reduce the relative humidity of a room, it does nothing to remove the moisture from the air.
Depending on the room's natural climate and the product being stored, either a desiccant or refrigerant (mechanical) dehumidifier will create and maintain the ideal climate for your products.
Refrigerant dehumidifiers work best in spaces where the temperature is at 20° C and above and humidity levels of 50% and above. They work on the humidity of the room and run when the humidity is above its set point.
Desiccant Dehumidifiers are ideal for controlling humidity and work well below 20° C.
If indoor temperature is not your concern but you require low humidity, then a desiccant dehumidifier can create and maintain below 50% relative humidity regardless of the time of year.
The Best Humidity Controlled Storage
To find out more about humidity controlled storage solutions and the variety of preservation and storage applications Humiscope has helped. Please visit our Storage and Preservation page or contact us for an obligation free chat about the HVAC technology we specialise in.