Long-Term Monitoring of Fresco Paintings in the Cathedral of Valencia (Spain) Through Humidity and Temperature Sensors in Various Locations for Preventive Conservation

Abstract

We describe the performance of a microclimate monitoring system that was implemented for the preventive conservation of the Renaissance frescoes in the apse vault of the Cathedral of Valencia, that were restored in 2006. This system comprises 29 relative humidity (RH) and temperature sensors: 10 of them inserted into the plaster layer supporting the fresco paintings, 10 sensors in the walls close to the frescoes and nine sensors measuring the indoor microclimate at different points of the vault. Principal component analysis was applied to RH data recorded in 2007. The analysis was repeated with data collected in 2008 and 2010. The resulting loading plots revealed that the similarities and dissimilarities among sensors were approximately maintained along the three years. A physical interpretation was provided for the first and second principal components. Interestingly, sensors recording the highest RH values correspond to zones where humidity problems are causing formation of efflorescence. Recorded data of RH and temperature are discussed according to Italian Standard UNI 10829 (1999).

Pinturas murales de la casa de Ariadna (Pompeya, Italia): Un estudio multidisciplinar de su estado actual enfocado a una futura restauración y conservación preventiva

“…Los datos de HR fueron registrados por un DS1923 con una exactitud de ±5% de humedad relativa y los de temperatura por un DS1922L con una precisión de ±0,5 °C. Los sensores de HR fueron calibrados antes de su instalación como se describe en (27). Por otro lado, los estudios microclimáticos fueron combinados con la termografía infrarroja con el fin de completar los resultados obtenidos.…”

“…RH were recorded by a DS1923 with an accuracy of ±5%RH, and temperature by a DS1922L with an accuracy of ±0.5 ºC. RH sensors were calibrated prior to their installation as described in (27).…”

Diferenciating Reproductions From Original Paintings: An Interesting Case Study

“…38,39 É curioso que no caso da catedral de Valência a obra original não tenha se perdido porque a nova pintura não foi feita sobre ela, mas sobre uma superfície adicional -uma nova cúpula -que se sobrepôs à original separada por mais de um metro. Os executores da segunda cúpula cobriram com a argamassa usada na montagem da segunda cúpula as bocas de quase todos os anjos góticos que cantavam e tocavam instrumentos, como que para calá-los, mas não tiveram a coragem de destruí-los, provavelmente reconhecendo e respeitando a beleza daquela criação.…”

Data acquisition and remote monitoring system for indoor environmental parameters

“…Taking these aspects in consideration a WSN can be easily deployed in structures where no prior plans were available or construction changes are not acceptable [8]. Successful integration examples of WSN indoor monitoring systems include museums [1], libraries [6], old buildings [7], transportation systems [9], etc. WSN are widely used in outdoor environment monitoring as well.…”

“…In the same time light is also one of the primary damaging factors and can produce different negative effects for indoor equipment and documentation [7].…”