The majority of artworks and artifacts housed in museums and libraries are made of natural materials that are susceptible to temperature and humidity. The moisture content of canvas, wood, parchment, and paper appears to balance with the humidity of the ambient air. External climatic conditions such as visitors, ventilation, and other factors can cause changes in the structure and physical characteristics of these objects. Which can cause permanent damage to paintings and other valuable works of art.
Museums and libraries must thus ensure that unique environmental conditions are precisely observed over extended periods. To ensure the protection and maintain the integrity of ancient artifacts.
Cooler temperatures extend the life of materials. If the relative humidity (RH) remains constant, a rapid temperature change will harm stressed metals, stone, films, plastics, or wax. High temperatures speed up the rate of oxidation and melt heat-sensitive materials. Inherently brittle materials, such as plastics and rubber, should be stored at cool temperatures with low RH levels. To slow down the natural deterioration process.
The temperature seldom has an impact on the objects themselves. Indirectly, but, fluctuating heat can harm or compromise objects.
Temperatures that are out of control can cause:
- Variations in humidity, which can damage sensitive objects. This is the primary explanation for temperature regulation.
- Speed up chemical and biological processes.
- Those materials to expand and contract. This is especially harmful to composite materials. Such as mud bricks, fiberglass, woods; which have parts that expand at different rates.
- People who are working or visiting collection objects may feel uneasy.
What is a Recommended Temperature Level?
The recommended temperature level for Museum objects should be at 16 to 20°C. These objects are unlikely to be harmed by moderately fluctuating temperatures between 10 and 20°C. Visitors would be uncomfortable in rooms below 16°C. Anything below 10°C will cause condensation and impact RH. Temperatures above 20°C are uncomfortable for visitors. And can hasten the deterioration of museum items.
Since museum stores are not populated by visitors, they can be cooler than 16°C. Keep in mind that objects must progressively acclimate between storage and display.
Relative Humidity Control
The relative humidity level should not fall below 40% or rise above 70%.
Sensitive objects can become dry and brittle when relative humidity falls below 40%. The most level is determined by the RH level at which fungal growth starts, which is at least 70%. It’s also crucial to keep RH levels stable.
Consequences of the Frequent Change of Humidity Level
Hygroscopic materials can swell and shrink regularly if the temperature of the air varies frequently. Internal stress and damage occur as a result of this. This is especially problematic in composite products. Where different materials deform at different rates. The expansion of one material can cause changes in the proportions of another, resulting in significant tension and, in the worst-case scenario, damage. Keep an eye out for such harm in objects like drum sleeves and paintings on wooden frames.
Moisture can also trigger or speed up the deterioration of many museum objects due to air pollution and other hazardous substances.
Mitigating the Factors that Affects Temperature and Humidity of the Museum
Many factors can influence the temperature and humidity within a house, space, or display case. It is divided into two factors.
First, are the external factors:
- If the building is in poor condition or poorly managed, excess water or rising damp may result in high humidity levels.
- If the building is not protected, sudden climatic conditions may trigger drastic fluctuations.
- Direct sunlight can cause significant heat gain and day-night changes on metal roofs and glass skylights.
Second, are the internal factors:
- Environmental conditions that vary from ambient conditions may be created by poor air circulation or ventilation.
- Heating systems that are used for warmth during the day can cause day-night variations.
- Moisture is produced by people, especially on rainy days.
- Localized pockets of high temperature and low RH can be created by in-case and spotlighting.
- Placed beneath objects, radiators, or heating units may cause significant drops in RH.
- Display cases may be made to create ideal microclimates for a particular piece. To avoid the reverse from happening, carefully choose your case.
Pay Attention to Frequent Fluctuations
Pay special attention to frequent fluctuations when monitoring your museum. As these can cause serious damage to museum objects.
The adjustments happen slowly enough for the objects to adapt. But quickly enough for the material to experience constant movement, tension, and exhaustion. Items would be less damaged if there are a few very fast variations every one or two hours. The objects would be able to acclimate slowly due to the gradual variations.
Some products are more vulnerable to variability than others. Keep products well packaged and covered in acid-free tissue. And a package or blanket when transporting to a location with varying environmental conditions. As a result, gradual acclimatization to the new conditions would be possible.
Essential Steps of Controlling Environmental Conditions
- Museums should do the following to mitigate the negative impact of external environments on the internal environment by:
- Conducting thorough construction and energy efficiency inspections. To ensure that the structure is in good working order and well protected.
- Maintaining the structure such that it acts as a shield against the elements.
- Keeping the windows shut at all times.
- Building double doors, rotating doors, or a foyer to keep entrance doors closed as much as possible.
- Reducing the impact of direct sunlight. Through using thermal insulation film on windows and skylights.
- Building and maintaining a stable atmosphere, use heaters, humidifiers, and dehumidifiers as required.
Since the main goal of temperature and humidity regulation is to maintain a constant relative humidity, the temperature may be expected to fluctuate moderately in favor of relative humidity stability. Instead of using a thermostat, a humidistat may be used to adjust the temperature. Humidifiers or dehumidifiers can be more cost-effective in conditions where humidity fluctuates a lot.
While maintaining stability is critical to museum care, some measures can be taken to improve energy efficiency. Consider taking a more versatile approach to environmental management. And reducing the use of artificial means to change temperature and humidity. This may imply a wider range of desired RH and temperature. But it may help you reduce your environmental footprint.
First of all, you should carefully determine the optimal level of relative humidity for your items. Sudden changes are undesirable. So it’s always best to keep an eye on things and figure out what you can do to better things in general. Such as shutting doors and windows and adding more ventilation or heating.
In almost every industrial or commercial use, AKCP has an EMS solution. A device that meets the demands of the industry can be found by combining a variety of intelligent base units (sensorProbe, securityProbe, and the sensorProbe+ series) and sensors with central management software (AKCPro Server).
Second, you need to maintain the required environmental conditions. Log and graph data over time, and get real-time notifications when user-defined sensor thresholds are exceeded. When in range, use it as a data logger with data buffered and synchronized to the gateway. IP66 rated enclosure provides waterproofing for use in outdoor environments. Mounting with DIN rail, wall hang, or cable-tie / pipe clamp. Pair with any AKCP Wireless Tunnel™ gateway.
Third, use SNMP Temperature Sensor. It is designed to record accurate temperature sensor data. It is ideal for giving advanced warnings of temperature fluctuations that can potentially damage sensitive equipment.
The importance of temperature and relative humidity in collection treatment cannot be overstated. If the conditions aren’t right, your things will be destroyed. Mold, rodents, decay, and warping are some of the issues that can arise if these elements are not kept safe and under control.
For your temperature and humidity control assistance, seek professional help at AKCP now!