Security and access control represent a major application domain for metal sensor technology, where it is used for the detection of concealed weapons, unauthorized metallic objects, and for enabling touchless access in smart buildings and vehicles. Walk-through metal detectors (WTMDs) and handheld scanners, employing balanced coil or pulse induction technologies, are standard in airports, government buildings, and public venues. Technological advancements have led to systems that can discriminate between threat and non-threat items, significantly reducing pat-down rates and improving passenger throughput; some international airports have reported a 50% decrease in false alarms after upgrading to modern multi-zone detectors. The global security metal detector market attained a size of USD 1.45 billion in 2023, and a comprehensive study by MarketsandMarkets anticipates it will grow at a CAGR of 7.2% to surpass USD 2.2 billion by 2030, a growth underpinned by persistent global security concerns and infrastructure development. A key innovation in 2024 was the commercial release of a new generation of AI-enhanced gate scanners that use advanced algorithms to automatically classify detected metal objects, improving threat identification accuracy by an estimated 30% in high-traffic environments. The future of security sensing lies in the concept of sensor fusion, where metal detection data is intelligently combined with inputs from other modalities like millimeter-wave imaging and biometric scanners to create a holistic security picture. Data from the International Association of Airport and Seaport Police suggests that 68% of major new critical infrastructure projects worldwide are specifying integrated, multi-technology screening solutions that include advanced metal detection. The post-pandemic era has also accelerated the adoption of touchless access systems, with shipments of access control readers incorporating proximity sensors for keycards and mobile credentials seeing a 25% year-on-year increase in 2023.