The thrust of airtightness specification and testing is derived from energy considerations. The application to healthcare buildings and specialist laboratory facilities embodies the same principles but derives the appropriateness of the criteria with reference to [a] producing controlled and controllable cascading pressure zones and [b] specifying or quantifying the potential exposure in the event of failure of mechanical ventilation.
The paper discusses the application of airtightness testing to two full scale physical models of isolation rooms. It will be shown that important information can be readily obtained to allow the commissioning of such facilities by determining component flows through closed doors, pressure stabilisers and the like. The modifications in approach necessary for application to Category 3 and above facilities are presented with discussion of the findings from field measurement data.