CORDIS - EU research results

An innovative technology, based on UV radiation, to strongly reduce the microbial activity of the air inside the store rooms of cultural heritage conservation institutes

Final Report Summary - ABIOS (An innovative technology ... to strongly reduce the microbial activity of the air inside the store rooms of cultural heritage conservation institutes)

The A-BIOS project concept was related to the European Community's target to decrease any activity concerning cultural heritage that would lead to air pollution. The project developed an innovative technology, based on ultra-violet (UV) radiation, to reduce the microbial activity of the air inside the store rooms of museums, archives and libraries. The biologic activity of the suspended air particles was decreased and the spread of fungal infections was minimised without the need of traditional fumigation with toxic gases, such as ethylene oxide. This conventional technology application posed risks to human health, polluted the environment and reacted with the materials causing further damage on cultural heritage objects. Thus, the adoption of the proposed alternative would be beneficial for air quality, for the objects' maintenance and for the health of the institutes' employees and visitors.

The developed technology incorporated proper shielding and catalysts of manganese oxides, supported by honeycomb graphite structures which reduced direct irradiation of objects and formation of ozone by the UV light. Two prototypes were constructed, to allow for the product testing at laboratory and commercial scale. The innovative equipment was assessed and its performance was evaluated. The potential integration of the device within an air-conditioning system was also investigated. The overall target, after achieving successful results, was to supply the device to the market as a complete solution for air disinfection shortly after the project completion.

The prototypes utilised stainless steel to totally reflect UV radiation and had three catalysts mounted at the outlet so as to avoid ozone emissions inside the deposits. Moreover, they were equipped with an air biological sampler to allow for extraction of fixed amounts of air from the final exit air stream. Parametric evaluations were carried out for both biological activity reduction of and potential ozone residual. After monitoring of their initial performance the devices were improved and refined, so as to be successfully implemented. All results of the optimised equipment tests were assessed using valid statistical analyses.

The A-BIOS ability to efficiently disinfect the air was verified with laboratory and field experiments. It occurred that sterilisation efficacy was higher than 90 % during in vitro tests. Moreover, A-BIOS could control the presence of airborne fungi. The highest performance was achieved towards xerophilic fungal species which were very dangerous for the preservation of paper material. Mould spores germination was also deactivated in case they were dispersed in the air. The device efficiency was reduced when tested within institutions; however, an almost complete sterilisation could be achieved in case the equipment operated for six consecutive hours. The decrease of fungi remained significant even during human presence in libraries' rooms.

In addition, the effect of the device on volatile organic compounds (VOC), ozone and nitrogen oxides' composition of the treated air was evaluated. During laboratory testing, A-BIOS decreased the substances' concentration. A similar experiment was performed in the field showing no significant alteration of the pollutants' presence occurred. Nevertheless, the performance of equipment was satisfactory and no additional ozone concentrations were observed in the treated air. As such the solution was promising and the acquired knowledge was disseminated and patented prior to its commercial development.