At West Gorton Community hub we were called to help draw up an indoor air, BREEAM air quality plan. As part of our plan we need to describe the steps that would be taken during design construction, commissioning and handover of the community hub to ensure that the indoor air quality was acceptable. The community Hub was located into an area designated as an Air Quality Management Area (AQMA) which was exceeding the objectives set in the national air quality strategy for nitrogen dioxide. In the surrounding area there were a small number of garages and light industrial units but there was no significant industrial sources of pollution. The primary source of pollutants in the surrounding area comes from traffic on the A57 Hyde road.
The building itself consisted of two stories, comprised of a medical centre, a pharmacy and a convenience shop. The medical center consisted of a patient waiting area an 13 consultancy rooms. At this property our main concern was Nitrogen Dioxide. Nitrogen dioxide is formed by a number of processes but primarily fro the combustion of fossil fuels. Excess air required for complex combustion of fuels introduces nitrogen into the reaction this forms nitrogen dioxide and nitric oxide, which are collectively referred to as oxides of nitrogen.
IAQ Plan and Removal of Contaminant Sources
The first step of our HEA-02 air quality plan was to have a well defined method of addressing the removal of contaminant sources. In order to ensure a high standard of indoor air quality, it was vital that all construction workers use practices that reduce the generation and distribution of indoor air pollutants. Waste paints and sealants will be sent off site once the relevant work is completed. We requested any construction waste or debris to be removed from site daily. In addition, electric equipment would replace gasoline-powered equipment wherever possible. This part of the strategy would be supplemented with the dilution and control of contaminant sources.
IAQ Plan and General ventilation
The next part of our BREEAM strategy was to ensure general ventilation of the building. In order for air quality to be maintained it was vital that all rooms be ventilated. We identified that outdoor air must be distributed throughout the building, meaning it was essential to ensure each space received the adequate amount of outdoor air. Workers would be instructed to ensure that ventilation systems were not obstructed by material or equipment place in front of the ventilation air intakes or discharge points. The next step was to store building materials in a dry location and remove moisture damage materials from the site. Where outdoor air supply was insufficient, local temporary exhaust ventilation was to be accomplished using fans, duct extensions and filters. The control of odours would be achieved through the use of Potassium Permanganate and activated charcoal.
IAQ Plan and Procedures for pre-occupancy flush out
Lastly, to ensure that any residual sources of pollution that may have accumulated in the building during construction and installation of internal finishes, a thorough building flush out would be carried out. This flush out would be carried out following completion of interior finishes and installation of new furnishings. At this stage the building should be flushed out with 100% outdoor air for a period of two to four weeks prior to occupancy. The minimum required flush out period prior to testing and occupancy would be 24 hours.