| 摘要 |
The present invention provides an apparatus and method for ensuring that a pass-by detector system is placed in "ready-to-alarm" mode when a subject carries a ferromagnetic threat, or an inanimate ferromagnetic object independent of a human subject passes within the physical zone designated for alarming to such a threat. A fail-safe alarm system consisting of dual detection systems solves the failure of motion-detection systems when confronted with non-heat producing ferromagnetic threat objects; and the failure of photo-beam detection systems when confronted with black, non-reflective clothing. Applications for the present invention include pre-MRI safety screening, as well as certain security protocols, such as banks, schools, prisons, and courthouses. |
