SAV’s David Bradbury said: “The key changes in BB101 2018 will have a very positive impact on creating a healthy and comfortable learning environment. For example, there is now clearer guidance on controlling draughts. To tackle the issue of poor outdoor air quality, better air filtration is now recognised as a necessary solution. At the same time, IAQ and noise levels need to be kept under control.”
In relation to thermal comfort, BB101 now defines acceptable temperature differentials between air delivered to the occupied zone and air already in it, for both natural and mechanical ventilation and different types of spaces.
To minimise the effect of polluted air, recommended filter grades are now derived from standards set by the World Health Organisation (WHO-2005). For polluted areas, filters to at least ePM1 55 per cent (= F7) are required. This means that for more or less any schools within the London area and other city centres, mechanical ventilation with filtration will be the only acceptable solution.
For IAQ the focus is now on outcomes, with greater emphasis on average carbon dioxide levels as a measure of actual IAQ, with personal requirement criteria for air flow rates (e.g., 8 l/sec/person) providing guidance only.
Other important areas addressed and summarised in an advisory document published by SAV include noise levels, filtration of supply air and the criteria used to identify and rectify overheating.
SAV’s BB101 overview can be downloaded here.