Recently we were commissioned to write up an indoor air quality plan for a business in London to ensure compliance with the BREEAM indoor air quality assessment scheme. The plan detailed the steps to be taken during the design, construction, commissioning and handover of a new office block to ensure that the indoor air quality was acceptable for work. The surrounding area of the office block is currently designated as an Air Quality Management Area exceeding the limits set in the national air quality strategy for particulates PM10 and Nitrogen Dioxide. The primary source of air pollution within the vicinity of the development is traffic sources. Nitrogen dioxide is primarily formed from the combustion of fossil fuels. In order to maintain indoor air quality and to minimize the impact of construction materials on the air quality, all products used would need to ensure that volatile organic compound emissions and formaldehyde stayed low.
General Ventilation
The key to maintaining indoor air quality is to provide a supply of outdoor air to the building. We recommended that all rooms be ventilated in accordance with the minimum it changes and fresh air requirements specified in the Chartered Institution of Building Services Engineers Guide. It’s important that outdoor air is circulated throughout the building, and the ventilation system must be balanced to ensure that each space within the building receives an adequate amount of outdoor air to accommodate the occupants.
Local temporary exhaust ventilation
In addition to a supply of outdoor air to the building, we recommended that operable vents and windows be opened to enable ventilation of the building during application of interior finishes. In spaces where no windows were present, we recommended ventilation in the form of localized temporary exhaust and building mechanical systems. To accomplish local temporary exhaust, site workers needed to use fans, duct extensions, and filters. In addition, local temporary exhausts would not be permitted to discharge near air intakes or other openings that lead into the building. Where special or distinct odours are present, special filtration media such as Potassium Permanganate or activated charcoal will be used.
HEA-02 Air Quality Plan Cleaning Schedule
To complement these efforts, we recommended that a program of regular cleaning be instigated so as to avoid the accumulation of waste materials, debris and odour producing waste. Likewise, waste bins and other waste collection containers should be emptied daily and cleaned regularly. Works needed to ensure that construction materials be kept dry and humidity levels controlled.
Overall Indoor Air Quality Plan
Overall, our BREEAM air quality plan aimed to ensure that the office block was safe by handover. With General ventilation, Local temporary exhaust ventilation and regular cleaning, the building would have minimal volatile organic compound emissions and levels of formaldehyde. By ventilating the rooms adequately we ensured that dampness and mould were unlikely to take root, and where natural ventilation failed we made use of local exhaust ventilation to ventilate during application of interior finishes.
