Eco-sustainable methods of cleaning up cultural heritage

The cleaning of heritage assets consists of the removal or thinning of strata deposited on a work throughout its existence. This treatment is usually motivated by the dysfunctionality of a stratum, whether due to intrinsic or extrinsic factors, and which alters or disturbs the integrity of the property. It has thus become one of the most controversial and complex treatments in a restoration process, which tends to be highly invasive and irreversible for the cultural property. In this sense, cleaning must not endanger or modify the physicomechanical properties of the surface, and therefore requires the utmost caution and responsibility from the restorer.

In recent decades, cleaning methods have been developed that allow for the regulation of removal by strata, increasing the safety and control of interventions. However, there are still some drawbacks related to the safety for the operator, the management of waste derived from the treatment and its environmental impact or the washing of non-volatile residues deposited on the surface, the solution to which is being formulated through nanotechnology, biotechnology and cryogenics.

The incorporation of cryogenic methods or green technologies as alternatives to other systems for cleaning, disinsectisation and elimination of microorganisms represents a scientific-technical advance in the methodologies applied to cultural assets. These eco-sustainable solutions are a commitment to ecological transition in the field of heritage, helping to reduce toxicity, waste and risks derived from the retention of solvents. In this way, we fulfil the commitment of Spanish universities and public bodies to the 2030 Agenda and the COP26 agreements.