Turnstiles

Turnstiles are access-control barriers designed to allow only one person at a time to pass through a doorway or corridor. They are used to regulate crowd flow, enforce entry limits, and deter unauthorized access in places such as transit systems, stadiums, museums, and office buildings. Modern turnstiles integrate with ticketing and identity systems to verify credentials before permitting passage.

There are several main types. Full-height turnstiles use tall fencing and rotating arms to create a strong physical barrier, typically used where higher security is required. Waist-high turnstiles are shorter barriers that rely on the user to control passage, often paired with electronic access readers. Tripod turnstiles feature three rotating arms and are common in mid- to high-traffic settings; their design supports unidirectional or bidirectional flow and can be configured for anti-tailgating. In contemporary installations, optical or electronic gates replace mechanical arms and rely on sensors, barriers, and access-control devices such as card readers, QR codes, or biometric checks. Turnstiles may operate in unidirectional or bidirectional modes and often include anti-tailgating features to prevent multiple people from squeezing through on a single credential.

Operation and safety considerations are central to design. Authorized credentials unlock the barrier, allow a single occupant to pass, and then restore the gate to a locked state. Many systems log entries for security and analytics, and emergency egress is supported by fail-safe openings. Materials are typically stainless steel for durability and ease of cleaning. Accessibility requirements often necessitate alternative accessible routes for people with disabilities.

History and use have evolved with transportation and security needs, from early mechanical devices to integrated electronic access control in modern facilities.