RESEARCH: Pollution Policy & Cultural Heritage:
Air pollution policy promotes cultural heritage preservation
Bringing together 13 partners in nine European countries and supported by the EU’s Sixth Framework Programme, the three-year CULT-STRAT project runs until 2007 and has an ambitious set of sequential objectives.
The first is to identify material indicators and threshold levels of pollutants – models, in other words – for developing sustainable maintenance and preventive conservation strategies regarding cultural heritage. Such modelling will lead to a ranking of pollutants for their corrosive and soiling impact on façades, outdoor statues and other monuments exposed to the open air. The second objective is to develop methods to estimate which of the cultural sites’ sensitive materials are most at risk across Europe.
The third, which builds on the first two, is to collect samples of how and where pollution is distributed across the continent and correlate this to Europe’s cultural stock, with the idea of eventually developing a strategic comprehensive map of the cultural sites most at risk. Based on the relevant pollution levels, such a map could project a spatial picture for 2010 and 2020 of the damage to cultural heritage sites and associated costs throughout Europe.
Building on recent research
CULT-STRAT will use the research completed by another EU-funded project, MULTI-ASSESS, which completed its work in April 2005. The latter created new models for predicting the rate of multi-pollutant deterioration of materials and the soiling of cultural objects. It also developed new tools, such as passive samplers, to collect and measure atmospheric concentrations of nitric acid and particles at specific sites, and an easy-to-use prototype test kit for heritage managers to assess pollution conditions at their site.
Much of the data generated by MULTI-ASSESS will be folded into CULT-STRAT’s wider-ranging objectives.
Dr Vladimir Kucera of the Swedish Corrosion Institute (SCI), coordinator of both projects, said CULT-STRAT “will evaluate the other project’s test kit, particularly for soiling trends. Pollution research has traditionally focused on the source, level and rate of corrosion on cultural buildings but we also have to investigate soiling rates. In fact, corrosion rates have decreased in Europe but the rate of soiling from particulate matter is still high.”
Just as with corrosion rates, the soiling of cultural heritage sites – i.e. how fast they get dirty – has implications for cost and maintenance. “We take a kind of holistic approach to the challenge of cultural preservation: soiling has to be included in economic calculations as well,” said Johan Tidblad, Kucera’s colleague at SCI, who also participates in the project. “Once you know how fast a building gets soiled, then you can do cost-benefit analysis. If a preservationist can prolong the period between cleanings, he saves not only money but the historic material itself. In many cases, cleaning methods can damage a façade. The fewer times you have to clean it, the better,” explained Tidblad.
|UNESCO World Heritage sites in Europe – Location and comparison of SO2 levels in 1980 and 2000|
Taking risksProducing a risk-map of the threats posed by pollution to Europe’s cultural sites is not as straightforward as it sounds. An essential first step for the CULT-STRAT team is to develop a methodology for assessing the stock of cultural materials at risk.
Taking the example of old churches, which are found everywhere in Europe, Kucera said that to accurately assess the pollution risk and cost of damage “you need to know how many square metres of a church’s façade are exposed to which pollutants, what the exposure levels are and the rates of corrosion. These can vary from one side of the church to another, depending on prevailing wind and rain, or where street traffic flows. It gets very complicated, so we’re only tackling a few sites in order to come up with a methodology. Besides, there are different notions across our continent about what constitutes cultural heritage so one methodology can’t address everyone’s needs. But we hope ours will offer a broadly applicable solution.”
Kucera said his team has already assessed cultural stock-at-risk in a selected area of Paris and, on a wider scale, mapped the approximately 350 UN-designated world heritage sites across Europe. “Our map has identified which of the sites are located in the most heavily polluted areas,” he explained, adding that the next task is to carry out detailed site assessment. “That is a vast task: full analysis of all the sites will take several decades, but at least the ball is starting to roll.”
Setting the standard
If CULT-STRAT participants have one overarching goal in mind, it is to influence how national and EU authorities frame air quality control standards.
“We aim to see the results of our work used by decision-makers to calculate the costs of corrosion and of prevention,” said Kucera. “Politicians always ask these kind of concrete questions. They want a cost-benefit analysis and it is very important that scientists enable them to do this. Ultimately we would like to see cultural preservation as a factor incorporated into EU legislation on air quality. Along with the other traditional factors taken into consideration, this would set limit values for pollutants regarding cultural objects.”
To help reach that goal, Kucera said his team will produce a clearly worded reference document that offers the main research results of both the CULT-STRAT and MULTI-ASSESS projects.
“It will be a tool for making strategic decisions, not only at the higher national and EU levels, but also for heritage managers working at regional, city and local levels. But it’s got to be readable for non-scientists. We don’t want to write it in a way that requires a PhD in chemistry to understand it,” he concluded.