Installation of an environmental monitoring system in the Chapel of Our Lady of Guia,Macau

Built in the early seventeenth century, the Chapel of Our Lady of Guia is one of the most important heritage sites in the historic centre of Macau. Its architectural features and wall paintings with Chinese and Western characteristics reflect the historical status of Macau as a hub for cultural exchange between China and the West. Since signs of deterioration have been observed on the wall paintings in recent years, it is very urgent and necessary to conserve them. In this paper, we will introduce the modern diagnostic techniques applied in the course of their conservation, including 3D laser scanning, high-definition digital photography, environmental monitoring, thermal infrared imaging, microwave scanning and penetration resistance tests. Comprehensive information on the current state of the wall paintings is collected, providing a solid foundation for their scientific preservation.