As a result of reaction of calcareous materials with volatile organic compounds (VOCs) degradation occurs. This process can be slowed down by keeping VOC concentrations as low as possible. Several sorbents were tested on their ability to protect eggshells against attack by acetic acid vapours. In the laboratory eggshells were exposed to 100 ppm acetic acid at 70-80%RH in the absence of and in the presence of copying paper, KOH-impregnated filter paper, Vokes charcoal/KOH filter mat, zeolite and MicroChamber zeolite containing paper. Unprotected eggshells showed a weight increase of 5%/month due to the formation of calcium acetate monohydrate. Sorbents containing a strong base (KOH), that have a preference for reacting with acid, perform better than calcium-carbonate containing material that reacts with acid in competition with the eggshells. In the presence of self-made KOH filter paper and commercially available Vokes mates the rate of degradation was reduced to 0.5%/month, on regular changing. When the sorbent was not replaced in time, saturation occurred and the rate of degradation increased to the level of the unprotected eggshells. Charcoal and zeolite containing sorbents can even release some of the adsorbed acid, becoming and emissive source. The effect of the sorbents is based on the actual reduction of the acid concentration in the enclosed space. The influence of the sorbents on the relative humidity is negligible. From the point of view of practicality and economy, KOH-impregnated filter paper is the best option for the protection of objects against acids. Vokes charcoal/KOH filter material proves to be a suitable acid sorbent with the additional advantage of containing a general sorbent to scavenge other VOCs as well. -- SCMRE