In Situ Damage Assessment of Microclimates for Cultural Heritage Preservation Marianne Odlyha Thermal Methods & Conservation Science Birkbeck College, University of London Indoor Air Quality in Museums and Historic Properties 6th INTERNATIONAL CONFERENCE November 2004 CNR-Padova

Topic : Innovative and existing tools to monitor the environment in museums (or microclimate of art objects) and the damage on art objects. Microclimate Indoor Monitoring in Cultural Heritage Preservation MIMIC

EC 5th framework : Subsection Improved damage assessment of cultural heritage Microclimate Indoor Monitoring in Cultural Heritage Preservation MIMIC (EVK ) Alcázar Segovia Cord roomNational Museum Denmark Room 134 EC Scientific Officer responsible: Dr.Johanna Leissner EC Scientific Officer responsible: Dr.Johanna Leissner

 Innovative tool based on piezoelectric quartz crystal technology exposed in Charlottenborg Castle, Copenhagen

22cmx14cm 7cm x 5cm QTS-3

Design of QTS-3 system Incorporates reference crystal (uncoated) so that the output signal is a frequency difference and gives the actual coating frequency or loading on the crystal. This will be referred to as F (kHz) Measured damage is then calculated from the change in the value of F (kHz) referred to as f (Hz) and expressed as a ratio (f/F) ie change in Hz per kHz of coating.

1. Example of data 2. Example of processed data: calculate f (change in frequency) / F (frequency at time =0secs). F is the loading on the crystal Uncoated crystal Coated crystals Petrie Museum, London Day s

End-users English Heritage Rangers after E1 ( ) 61 days f/F(RM) =16 c.f Chiswick RM(f/F) =25 

Crystal posn Days f/F Exposure in British Library to

Processing of Climate data Climate data from selected sites (Southern Europe), & (Northern Europe) have been compiled in one large climate data file: Grand Unified MIMIC Data Base “GUMD”. GUMD, and related data, are all available on the MIMIC website. For data reduction we record the number of times T & RH values exceed certain limits as a preparation for calculating risk factors. Light dosage (luxh) is calculated for each exposure period. Pollution dosage is also calculated (  g/m 3 h).

Processing of climate data (National Museum of Denmark) & pollutant levels NMD Room 134 PQC array Start dateEnd dateNo. Days 24/07/200202/09/ T_avT_maxT_min T variations 0,0-2,0C2,1-4,0C4,1-6,0C6,1-8,0C>8,0C RH_avRH_maxRH_min RH variations 0,0-5,0%5,1-10,0%10,1-15,0%15,1-20,0%20,1-25,0%>25,0% TWPILightdose (kluxhrs) Dose SO 2 Dose O 3 Dose NO 2 Dose NOxDose HNO 2 Dose HNO

NMD after 2 exposures in Rm 134 (July - Sept 2002) E1= 30 days E2= 40 days Ecum=70 days Response (f/F) resin mastic coated crystals in positions 2, 4and 7 RM response NMD134 NMD134 Vestibule Passive sampler dosimeters interrogated at monthly intervals Includes one exposure in Vestibule Response PQC (f/F) vs no. of exposures

Processing of climate data (National Museum of Denmark) & pollutant levels NMD Vestibule PQC array Start dateEnd dateNo. Days 2/07/200212/08/ T_avT_maxT_min T variations 0,0-2,0C2,1-4,0C4,1-6,0C6,1-8,0C>8,0C RH_avRH_maxRH_min RH variations 0,0-5,0%5,1-10,0%10,1-15,0%15,1-20,0%20,1-25,0%>25,0% TWPILightdose (kluxhrs) Dose SO 2 Dose O 3 Dose NO 2 Dose NOxDose HNO 2 Dose HNO

Thermokinetics (Advanced kinetic calculations) Effect of temperature modulations of sample maintained at 40  (+/- 40  C) for 1 year

Compare light and pollutant dosages received in NMD (134) and NMD Vestibule much higher light dosage higher ozone dosage lower NO2 higher HNO3 and much higher f/F

Calibration: Effect of long exposure (14hrs at 10ppm) NO 2 on resin mastic coated crystals positions 2,3 and 4 exposed   Gas on Gas off  (f/F) vs hrs of exposure Exposure 10ppm 12 hrs gives same response as 20ppm for 6 hrs

Calibration (f/F) vs Dosage (ppm hrs) Petrie 29.7 ppm hrs (1month) NMD V ppm hrs(1month) NO 2 ppm hrs

Calibration : Modulated RH ( 50%  70%  50%  30%  50% ) imposed on resin mastic coated crystal exposed to NO 2

Site information from FTIR data: example of strip frame data for egg tempera strips exposed at Osterley Manor Similar table with exposures for the same period but giving f/F values for the sites

Multiple external reflectance with the Dura AmplirIR FTIR

FTIR Mastic Blue=Isle of Wight(direct sunlight 12 hrs) Red=Chiswick (70 days, f/F= 25) Purple= Control, Black=British Library (after 189 days, f/F = 8.8)

Climate data reduction expressed in terms of TWPI values for the duration of dosimeter exposure. 14  C, 40%RH = 124 Years 20  C, 50%RH = 44 Years (heat for human comfort lowers TWPI) 28  C, 70%RH = 10 Years In MIMIC British Library most controlled site and for periods of dosimeter exposure Damage values are registered by coatings are low. Indoor pollutant levels are also lowest of the sites. TWPI values are low (c.30-40) MIMIC dosimeters together with TWPI values describe more realistically the quality of the environment. Conclusions

Summer NMD 134 June 2002 TWPI 27 ALC MM 45 ALC Cord 54 NMD 134 July 2002 TWPI 19 ALC MM 36 ALC Cord 34 TWPI decreases, dosimeter damage values increase (pollutants ALC MM increase in O 3, NMD increase in NOx) Winter SAC Oct-Nov 2002 TWPI 50 SAC Jan-Feb 2003 TWPI 91 TWPI increases, dosimeter damage increases, and pollutant dosage NOx increases Charlottenborg Castle (TWPI 97) has lower level of pollutant dosage NOx and lower level of dosimeter damage. Conclusions

Benefits MIMIC project Small portable system which can be exposed for 1-3months either as passive sampler or continuously recording. It will incorporate RH,T sensor. Option of telemetry link will be possible. Optional small palette with similar coating (egg tempera, varnish). Readily analysed by FTIR. Possible use for screening damage during transport of works of art (Meeting organised by SIT,Madrid,Nov 2003) Database of damage values obtained at monitored sites (delta f/F) and chemical data (FTIR). Database of damage values obtained from accelerated ageing..

Acknowledgements EC 5th Framework DGXII “Protection & Conservation of European Cultural Heritage” ”. for funding the MIMIC project Nancy Wade, paintings conservator University of London, Birkbeck College, Dr.J.Slater Dr. M.Appleton (QuartzTec) Dr.Q.Wang, R.Campana, Dr. A.Beard, and C.F.Wilson University College, Dr.K.Pratt (UCL Chem) CNR- Istituto Inquinamento Atmosferico & IROE-CNR, Dr.F. de Santis, Dr.M.Bacci, Dr.M.Picollo, CNR-Rome and Florence,Italy El Alcázar,Segovia,Spain, Victoria Smith. National Trust, U.K., Linda Bullock, National Museum of Denmark, Copenhagen, Morten Ryhl-Svendsen, Dr.Tim Padfield, and Lars Aasbjerg Jensen FOM Institute (Netherlands) Prof. J.J.Boon & Dr. E.Ferraira Tate Britain Conservation Dept.,Dr.B.Ormsby,Stephen Hackney & Dr.J.H.Townsend Winnats Scientific Services Dr.R.West, XPS analysis English Heritage David Thickett British Library K.Matsuoka

Compare light and pollutant dosages received in NMD (134) and NMD Vestibule much higher light dosage Higher ozone dosage Lower NO2 Higher HNO3 And much higher f/F