New developments constructed in accordance with the Breeam scheme require a creation of a robust air quality plan referred to as IAQ plan. The purpose of the air quality plan is to limit the amounts of air contaminants on site during the construction phase and post construction or the benefits of the future occupants.
Briefly the IAQ plan is intended for use in preparation of a project specification covering indoor air quality requirements. The specification includes the requirements of BREEAM and includes specifications for construction products, construction site management, construction sequencing, HVAC operation during construction, product installation, building flush-out and IAQ testing. The Indoor Air Quality Plan describes the steps that will be taken during the design, construction, commissioning and handover of the development to ensure that the indoor air quality is acceptable.
In preparation of an indoor air quality plan a consideration must b taken of the existing situation on the development site. The most important factors to be considered in this area are the presence of significant sources of industrial pollution. This is especially important in the development is located in the areas designated as air quality managements zone by the Government.
In this particular development I have been preparing air quality plan for a three industrial units located on the industrial outskirts of London. The particular area has been designated air management zone of exceeding the national air quality objectives for nitrogen dioxide. The development site is situated in close proximity to railway lines to the east and north and to a major road to the West. Large industrial complexes are located to the west and to the north of the site. The larger area contains numerous important transport links. As well as being home to a major airport, the borough is crossed by the two motorways and several major A roads, attracting traffic into the borough and encouraging traffic to pass through it. All of these sources, therefore, generate a significant air pollution burden for residents. The major causes of poor air quality arise from the major roads that traverse the borough and from the operation of the airport.
Nitrogen dioxide is formed by a number of processes, however, in London the main cause is from the combustion of fossil fuels. Excess air that is required for complete combustion of fuels introduces nitrogen into the reaction; this forms nitrogen dioxide and nitric oxide, which are collectively referred to as oxides of nitrogen. Emissions are primarily nitric oxide (NO) but this is converted into nitrogen dioxide NO2 in the atmosphere through chemical reactions with ozone (O3).
Other major pollutants often considered for the purposes of indoor air quality plans are particulates P10 and occasionally oxides of sulphur. In special circumstances where a particular pollutant is generated from a nearby source specifies approach needs to be taken to limit and/ or eliminate the pollutants from the indoor areas. An example a special situation would be presence of a refinery, sugar processing plant, rubber manufacture and others. In these unique circumstances consideration needs to be taken in regards air managements and filtration in the new development.
By Tomas Gabor
