Assessing the value of Green Conservation for Cultural Heritage: positive and critical aspects of already available methodologies

In recent years, the use and the necessity of green materials and methodologies have been promoted in the field of Cultural Heritage, aiming to a low impact on the operator health and the environment [1, 2]. Strictly connected to the green conservation is also the concept of sustainability: a complex topic that involves three main pillars (environment, society and economy) and that often leads the direction of the intervention and research in the Cultural Heritage field [1, 3]. For a long time, in restoration and conservation science, the main goal was searching for the most compatible solutions with the materials of the artifacts not thinking sometimes about the possible issues for the operator and/or for the environment. Recently, thanks also to an increasing attention to a respectful consumption of environmental resources and waste management, new scientific methodologies has been proposed for more sustainable and green interventions, promoting furthermore the concept of preventive conservation [3, 4, 5]. The aim of this work is to present an overview about some of the most interesting technologies and methodologies already available as alternative to traditional and more invasive/dangerous restoration treatments towards artefact, operators and environment. In particular, the methods described in this paper have been critically analysed focusing on which might be the positive and negative points considering the convenience of use by the restorers and the reasons why these methods are still not well known and diffused. Up to now, still most of the green methodologies and products are proposed by Universities and research centres and do not reach the industrial scale production as often not economically attractive or supported by private or public institutions.