The modern turnstile was invented in the early 20th century as means of access control mostly for amusement areas and transit systems. Nearly 80 years later, the turnstile remains an indispensable component of venue security, especially as companies update an old invention to fit into the post-9/11 world. From the prototypical “bum tapper” tripod to turnstiles with glass barriers, not arms, to barcode-scanning walkthrough models and more, security personnel can choose from nearly endless options when installing or retrofitting turnstiles. Ultimately, the venue’s needs and level of security it must enforce determines what is the right turnstile.

Morgan Stanley Discover Card in Chicago uses Automatic Control Systems’ PNG380 to secure its lobby

Mechanical Turnstiles: The mechanical turnstile is the basic, tripod-arm mechanism perfected in the late 1920s by John Perey and Conrad Trubenbach. Perey Turnstiles remains one of the industry’s leading manufacturers.

This type of turnstile works best in applications such as stadiums or concert halls, where attendees do not need to swipe an identification card. It also is a cheaper alternative to optical turnstiles.

Optical Turnstiles: This style uses laser sensors rather than arms and often is integrated with an existing access control system.

Also, optical turnstiles tend to have glass barriers that slide out of an authorized user’s path. If there is no glass barrier and the turnstile presents an open passageway, sensors work with the access control system to detect trespassers and will sound alarms. The optical turnstile is the device of choice for corporate lobbies and government facilities or anywhere the turnstile needs to integrate seamlessly with the surroundings and provide electronic security.

Blended Turnstiles: Blended models incorporate the top features of mechanical and optical turnstiles, working best in facilities such as stadiums or transit systems. The combination turnstile reads tickets or barcodes without requiring the more sensitive information, such as biometrics, optical turnstiles require.

Portals: Consider the portal the imposing bouncer of turnstile security. It typically stands at full height, features revolving or interlocking doors, can work with metal detectors and electronic access control systems, and can even be built with armored glass. This type of turnstile works for any facility needing a top level of security.

One Penn Plaza Automatic Control Systems PNG390 Optical Portal, All ADA Handicapped-Accessible Lanes

Turnstiles serve three main functions, says Johnathan Watson who works in international sales for the security division of Alvarado Manufacturing Company Inc. There is the obvious, access control; there also is the ability to count people entering and exiting a venue; and turnstiles provide crowd control, governing the flow and direction of movement.

Watson cautions any turnstile that is not full-height must have the direct supervision of security guards. He says anyone who really wants to can jump over or crawl under a waist-high mechanical or optical turnstile.

This is an especially important consideration for unmanned areas. If there are no guards on duty, “it’s always got to be a full-height revolving turnstile,”Watson advises.

The benefits of turnstiles extend beyond the aspects of security. When using models that count people, managers can delineate a preset capacity, so an alarm tells guards when a building is reaching its capacity limit as specified by the fire safety code or the number of available seats. A counting turnstile also can be used to predict staffing levels. If building managers know which turnstiles are going to be used most and at what time of day, they can post security guards appropriately.

The companies Public Venue Security spoke with agree on at least three main areas for end users to consider when choosing turnstiles: tailgate detection, appearance and ADA compliance. All of these companies employ tight tailgate detection – typically one quarter inch — making it difficult, if not impossible, for piggybackers or jumpers to get very far, especially when facilities have security guards on hand.

Effective tailgate detection also means the turnstile in question will not detect wheelchairs, luggage or other items as another person, thereby instigating a false alarm.

Throughput rates are another important factor in deciding on turnstiles, but Watson cautions potential buyers to be wary of companies hyping numbers. Realistically, he says, throughput will run 3-4 seconds per person. “How does a person operate?” he queries. “It depends on how fast someone pulls out their card and swipes it.”

Along those lines, Smarter Security Systems Ltd.’s Pam Fiore, director of sales, touts her company’s one person per second throughput, but the company does note response time depends on a facility’s access control system.

PathMinder President Gennady Reshetnikov advises facility operators to deploy enough turnstiles to accommodate peak traffic, never allowing a long line to form. In addition, they need to figure in the lag due to access policies, such as whether personnel need to use a card entering and existing or just upon entering.

He also adds that keeping the turnstiles up and running by not linking all of them to the same control panel can mitigate traffic jams in the event of a control panel failure.

Fiore also speaks to the importance of setting tension in mechanical or mechanical/optical turnstile arms. Being able to set tension eliminates the danger of injury, she says.

Watson, Casson, Fiore and Reshetnikov also advise venues to use turnstiles that adhere to the Americans with Disabilities Act and more universal guidelines that allow access for the disabled.

Compliant turnstiles have features such as gates or kickplates, are wide enough to accommodate wheelchairs, and, when it comes to rotating or sliding portals, swing or slide wide and slowly enough to allow wheelchairs to pass safely.