A safe haven is a new concept in line with robust resilience where building occupants faced with an external or internal threat move to areas described as a "Safe haven". The identification of a safe haven will depend on many environmental conditions and these must usually be controllable. The criteria for a Safe havens for explosion are almost diametrically opposite to those required to protect building occupants from bio terrorism or CBRN events. The safe haven can be constructed from plastic and tape although suffocation in this primitive type of defence must be considered. The use of currently installed engineering controls such as air pressure, laminar air flow, temperature will provide far greater protection although the actions of other tenants within a building may compromise any safe haven unless controls are put in place.