Historical museums and depositories contain collections with a number of lead objects or historical documents with lead seals. Lead is a metal which has good corrosion resistance under atmospheric conditions. On the other hand, lead corrodes in an activity in an environment which contains volatile organic compounds (mainly acetic acid and formic acid). In a depository environment, sources of volatile compounds can be the historical documents themselves, wood, plastics (those made from cellulose acetate), polyvinyl acetate adhesives, varnishes, oil or emulsion paints, etc. The aim of this work was to compare the efficiency of commercial adsorbents (activated carbon, activated alumina, zeolite, and bentonite) in the acetic acid vapours. The lead corrosion rates were determined by using lead resistometric probes. Activated alumina and activated carbon were found to be the most effective adsorbents of acetic acid vapours. On the other hand, the available zeolite had the worst sorption ability compared with the other tested substances.

A variety of techniques are available for monitoring metal corrosion in electrolytes. However, only some of them can be applied in the atmosphere, in which case a thin discontinuous electrolyte film forms on a surface. In this review, we describe, evaluate and compare both traditional and state-of-the-art real-time corrosion monitoring techniques to identify those suitable for atmospheric conditions. For atmospheric corrosion monitoring (ACM), electrochemical impedance spectroscopy (EIS), electrochemical noise (EN), electrical resistance (ER) probes, quartz crystal microbalance (QCM), radio-frequency identification sensors (RFID), fibre optic corrosion sensors (FOCS) and respirometry, the underlying principles, characteristics and application examples are described, and their advantages and drawbacks outlined. Finally, the techniques are compared in terms of their sensitivity, ease of setup, data processing, ability to identify underlying corrosion mechanisms and applicability in different fields of atmospheric corrosion protection and research.

Lead used to be a common material for setting seal to historical documents. Lead seals formed parts of historical documents as a guarantee of their legal validity. Disinfectants are commonly used during the restoration of historical documents. They successfully remove mould, bacteria and microscopic fungi from the surface of parchment documents. However, some disinfectants could also be a source of corrosion damage to lead seals. This work was carried out to examine possible corrosion damage to lead seals caused by disinfectants [a solution of carbethopendecinium bromide, a solution of glutaraldehyde, butanol (vapours), a solution of 1-propanol, 2-propanol + ethanol called Bacillol AF], which are commonly used during restoration of historical documents. The lead corrosion rates were determined by using lead resistometric probes. The solutions of carbethopendecinium bromide and glutaraldehyde increase the lead corrosion rate and corrosion products based on carbonates, nitrates and organic lead salts are formed on the lead surface. The most appropriate disinfectants for the restoration of historical documents with lead seals are alcoholbased solutions, such as butanol (vapours) and a solution of 1-propanol, 2-propanol and ethanol called Bacillol AF.

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