Indexes to qualify air quality in closed locations

The OQAI has been working on the production of an air quality index since 2006, to determine the state of air pollution in closed living areas.  It is difficult to produce such an index due to the thousands of chemical, physical and microbiological pollutants that may be present in air inside buildings, heterogeneously in space and in time.  Another objective is to find one or several “tracers” of this pollution.  However, the lack of management values for determining the relation between measured pollution levels and reality makes the test more complicated.  Another difficulty is to find action levers to be applied in situations identified as being problematic.

There are already about ten indoor air quality indexes (produced in France, the United States and Taiwan) in different types of locations, and particularly homes and offices.  These indexes are all different in their composition, in weighting of the pollutants considered, and in the reference values used.  But particularly, the very small amount of operating experience with the use of indexes, their understanding by users and the cost of use demonstrate that these indexes are no longer used, although the authors do not explain why, demonstrating the difficulty with their acceptance.

Social and environmental psychology approach
A qualitative exploratory investigation was carried out with building managers (homes, tertiary buildings and schools), the people ordering the index, etc., in order to analyse motivations and perceived risks related to the production of a simple index useful across the country and to enable a better match between methods by which it is implemented and its potential users.  Perceived difficulties are not only technical.  Thus, the time approach appears in the concerns of different players.  When questioned about the most appropriate time for making air quality measurements, interviewed persons consider that the index should reflect the air quality in buildings during the different stages of its life:  construction, delivery, one week or one month after delivery, during renovation and a few weeks later as a function of changes to materials or the use of buildings.

Many other psychosocial and psycho-environmental criteria need to be taken into account before this tool will satisfy the expectations formulated by the government authorities and the OQAI that is developing it.  "The index is presented like a threat and there are many perceived risks:  health, social, psychological, economic and legal risks.  The behavioural aspect is overriding in risk management and the index must be accompanied by a study on conditions for its acceptance".  The challenge is not financial, it is in practical every day use.

Information provided by the indexes must relate to improvement actions.  Apart from the role of buildings and the fittings considered (it is known that they can emit more or less volatile organic compounds depending on their age), there is a consensus about the importance of the behaviour of building users on indoor air quality.  The intimate part is difficult to observe.  There is no point in delivering a building in which indoor air quality is good when the building is empty if behaviours are inappropriate because of various polluting activities, for example cooking with no ventilation/ aeration, overcrowding, bad thermostat settings, use of many deodorising products, aerosols and care products, emissive or waxed furniture, tobacco smoke, do-it-yourself activities, etc…

Inform, explain, know

The conclusions of the study show that the index could act as an element contributing to triggering popular awareness about indoor air quality.  This subject is still not well known and it is accompanied by many preconceived ideas that have to be corrected.  These include the conviction that indoor air pollution can be "smelled" or that indoor deodorants make the air healthier.  Quite the contrary, pollution is not necessarily accompanied by bad smells, while indoor deodorants may contain VOCs and can add chemical pollutants to air, which is undoubtedly already "polluted".

Séverine Kirchner, scientific manager of the OQAI, says "these indexes will be intended to awaken and increase awareness of different types of public, including Building Managers, Government authorities and inhabitants about indoor air quality, so that they can modify their behaviours and prevent risks such as respiratory diseases or caulking situations that can be harmful to health."

An indoor air quality culture still needs to be created, by assisting the population through awareness and information tools to encourage well-informed use of these indexes.

Obviously, the possibility of measuring the indoor air quality gives better knowledge of the indoor environment and pollutants characterising it.  The index is awaited as a means of measuring the magnitude of the problem in environmental and also sanitary terms.  Therefore the challenge is based on development of regulatory, technical and behavioural action levers.

A dedicated work group

CSTB carried out the study on motivations and perceived risks related to the production of indexes within the OQAI’s “indoor air quality indexes” working group in which CSTB, the LHVP (City of Paris Health Laboratory), the AFSSET (French Agency for Safety and Health in the Environment and at Work), Aéroports de Paris, APPA (Association for the Prevention of Atmospheric Pollution), Fractal, INERIS and the Paris OPAC.  It was financed by the Ministries for Housing, Ecology and Health, and CSTB.

Operational mould contamination index

The OQAI has already determined a specific index to identify contamination due to moulds.  It is applicable everywhere we live, alone or in combination with other pollution tracers.  This index is based on experimental or laboratory work and by interpreting data obtained from the national campaign in homes carried out by the OQAI, and it was developed using an innovative technique based on the identification of specific volatile organic compounds (VOCs) that were used as tracers to detect the development of fungi in indoor environments.  It was applied on data in the national “housing” campaign in parallel with descriptive data on the presence of moulds.  Out of 496 homes that were included in the study, nearly 40% are apparently contaminated by moulds, while about 70% of these show no visible signs of mould.  Hence the advantage of developing such a "tracer" method.