Design and implementation of a nonthreatening barrier for deployment in special usage holding areas

This paper describes a barrier topping designed to be less visually aggressive, but equally effective, to orthodox security barriers. These generally employ one or more components which have the potential to physically injure a person contained within the compound, should they attempt to breach the barrier. The concept on which the barrier is based is one of passive resistance rather than visual deterrence, with particular focus on the defeat of an outside rescue attempt or the use of ropes and bringing aids from within. The design is based on a 120/spl deg/ sector of a 1000 mm diameter section fitted to the top of an existing wall structure. The free edge of our 120/spl deg/ sector is fitted with a series of stiff, steel pickets, approximately 900 mm long, 72 mm wide and spaced at 154 mm centres. These pickets project downwards from the 120/spl deg/ sector at approximately 45/spl deg/. The effect, when standing at the base of a wall fitted with our shroud, is similar to standing under a small verandah or roof. The steel pickets, in combination with the 120/spl deg/ sector, make it effectively impossible to climb unaided over the barrier. The design removes the threats of height and sharp deterrent barriers, which are often unsuitable for use, particularly in juvenile institutions and psychiatric hospitals.