Wind effects on mechanically ventilated asbestos containment zone

Asbestos abatement from buildings is performed under controlled conditions, maintaining a depressurization within the containment volume, to prevent the suspended particles from escaping into the outdoor environment. Although different government authorities have established the requirement for this depressurization, external wind effects can cause momentary breaching of this containment achieved by means of mechanical ventilation system. This paper aims at analyzing and quantifying these wind effects by performing wind-tunnel tests on a reduced-scale model of an idealized building installed with a mechanical ventilation system. Tests are performed for two wind directions (i.e. α = 0° and α = 45°). The results show that negative internal pressure is maintained for the tested cases in all instances. However, further detailed analyses of internal-external pressure differences reveal that a breach in containment may occur at localized regions where high external suction pressure occurs due to the separation of flow at building edges.