The effect of temperature on emissions of carboxylic acids in passive climate controlled repositories with cultural heritage collections

This study investigates the effect of reducing temperature on the emission of carboxylic acids and other volatile organic compounds (VOCs) released from museum objects. Volatile car-boxylic acids cause deterioration of cultural heritage collections, e.g. tarnishing of metals, salt efflorescence on calcareous structures, and acid hydrolysis of organic materials. The concen-trations of VOCs and carboxylic acids in air were determined in a test chamber set-up. Active sampling of VOCs was performed on Tenax TA® with subsequent thermal desorption and coupled gas chromatography/mass spectrometry (TDS-GC/MS) analysis. Carboxylic acids were trapped on silica gel tubes and analyzed by ion chromatography (IC). The results show that reducing the temperature from 23°C to 10°C will reduce the emission of carboxylic acids from selected cultural heritage materials to 27-68%.It has to be clarified if reducing tempera-ture can have a beneficial effect on air filtration requirements in repositories with passive cli-mate control in Northern Europe.