From concept to validation of a wireless environmental sensor for the integral application of preventive conservation methodologies in low-budget museums

The effective implementation of preventive conservation strategies requires tools to continuously measure the environmental conditions to which the cultural objects are exposed. In this sense, the European Horizon 2020 project CollectionCare aims to provide an affordable preventive conservation service for individual objects focused to small museums with limited budgets. Although the use of data loggers has been a must in the past, new deployments tend to use wired and wireless sensors that provide real-time information and the ability to instantly analyse the data, allowing immediate action to be taken in the event of a threat towards a cultural object. For already constructed buildings, wireless systems have the advantage that, a priori, deployments are simpler, faster and cheaper, but have to deal with complex heritage environments with long distances to be covered and very thick walls to cross. In many cases, commercial systems of this type are not economically viable for small museums with limited budgets. Moreover, conservators who try to approach such solutions are often overwhelmed by unclear technical specifications that do not allow them to determine whether the solution fits their environment or not, giving rise to great frustration. Among others, the CollectionCare includes the design of a specific low-cost wireless sensor, being the aim of this article to present to both technical and non-technical readers, the design choices made regarding the housing, attachment method, power source, wireless transmission technique and selection of the environmental sensors following European standards. Also, the effective implementation of the device in three stages to prove the concep until to get a near-production version is presented. The developed device has been deployed in museums in Belgium, Italy, Greece, Latvia, Denmark and Spain, and the validation results are presented, showing that it is feasible to have a cost-effective proposal that it is easy to install and configure and can operate for 10 years without the need for maintenance or battery replacement except if it is needed to comply with annual recalibration if standards such as ISO 11799:2015 are required.