Preserving art: Exploring indoor environment quality's impact on museum exhibits and paintings

According to UNESCO, there are over 100,000 museums across the globe. They are home to priceless artefacts, allowing individuals to be immersed in different times and places. However, indoor environmental quality (IEQ) is crucial in determining their integrity and longevity.

What is Indoor Environmental Quality (IEQ) and why is it important?
IEQ is described as the conditions within an indoor environment; these include acoustic comfort, air quality, thermal comfort, ventilation, and visual comfort. There are many reports on the influence of IEQ on human health and productivity. However, very few have reported on the effect of IEQ on museum exhibits and the paintings they contain.

What is the impact of IEQ on the preservation of museum exhibits and paintings?
Organic and inorganic pollutants
The display cases used to store artwork can create unique microclimates to trace compounds accumulating in indoor spaces and can reach much higher concentrations of pollutants than those found in the outdoor air. Elevated concentrations of organic and inorganic pollutants have been found within enclosed frames, for example, and can significantly contribute to the degradation of exhibits and paintings. Introducing dirt, dust, and microorganisms into the environment can also gradually form a film on the surface of the painting that proves difficult to remove without causing damage.

Thermal comfort and humidity
Extreme temperatures can impact the stability of paintings, and the process of thermal contraction and expansion has the potential to cause structural damage. Humidity fluctuations can lead to the expansion and contraction of a painting’s support structure, causing stress on the paint layers resulting in cracks or flaking. Additionally, high humidity can promote mould growth, which poses a serious threat to paintings, especially those created on organic materials like canvas.

Cundall's Air Quality team monitors museums and libraries in line with the Purafil Technical Bulletin-600A, Environmental Control for Museums, Libraries, and Archival Storage Areas, _20­04. This involves sampling ambient pollutants outside the gallery and measuring parameters (including atmospheric corrosivity) within the galleries to assess the IEQ, followed by laboratory analysis of the samples to provide data on air pollutant concentrations. Typical problems the survey may highlight are the presence of acidic contaminants (e.g hydrogen fluoride, hydrogen chloride, hydrogen bromide, phosphoric acid, and sulphuric acid); atmospheric corrosivity; poor control of temperature and relative humidity; as well as suspended particulate concentrations.

Cundall produces interpretive reports and can advise on the delivery of tighter environmental controls (i.e., temperature and relative humidity) and suitable integration methods (e.g climate control systems, lighting considerations, regular cleaning, sealing and insulation and storage conditions) in accordance with the requirements of best practice guidance.

We work closely alongside the building services team to adjust the building ventilation strategy - consideration should be given to fine-tuning air filtration rates, and the addition of particulate filters and activated carbon filters. Further testing is also recommended to quantify any improvements the refurbishment programme delivers and ensure any indoor environmental quality issues have been resolved.

Summary
In the intricate relationship between art and the environment, the importance of IEQ cannot be overstated. By understanding and advising on suitable environmental controls and integration methods to control contaminants, humidity, and temperature, we can continue the preservation of the treasures within these environments, so they can continue to educate and inspire future generations.