Gym Gate Features and Limitations: Understanding Tailgating Prevention Technology

When you invest in access control gates for your gym, understanding their features and limitations is essential. Although modern gates offer excellent security, they are not perfect barriers against all unauthorized users. Let’s examine how these systems work and where their challenges lie.

Two Main Types of Glass Gates

Glass gates fall into two main categories, each with its own operating mechanism and application.

Flap gates are equipped with flaps that retract inward with a guillotine-like motion. You see these commonly at subway stations around the world. The flaps retract into the housing to allow passage and slide back to close the opening once an authorized person has passed through.

Speed gates operate differently. Their flaps open in the direction of travel, like saloon doors. These are often used at airports and upscale office buildings. The flaps swing open in front of the user and close behind them after passage.

Both types serve the same basic purpose—access control—but their mechanical differences create different performance characteristics, particularly in their ability to prevent tailgating.

The Ongoing Challenge of Tailgating

Tailgating has always been a significant challenge for glass gates regardless of type. Tailgating occurs when an unauthorized person follows closely behind an authorized person and passes through the gate before it closes.

Manufacturers have traditionally differentiated their products based on sensor technology. Each manufacturer has attempted to find the optimal sensor positioning and logic to close the flaps as quickly as possible after a person passes through. However, no manufacturer has achieved perfection in this.

This is not due to poor design or lack of effort. The fundamental limitation is that sensor technology itself simply cannot perfectly detect every tailgating attempt under all conditions.

How Infrared Sensor Technology Works

Most gates use infrared sensors as their primary detection method. These sensors operate on a simple but effective principle.

A transmitter emits infrared light, and a receiver detects it. The transmitter and receiver can be located on the same side of the gate or on opposite sides (mounted to different gate frames). The infrared beam remains continuously connected until an obstruction breaks the connection.

This beam breaking and reconnection provides data that the sensor technology and its logic use to control the gate.

For a sensor to detect two separate people, there must be physical space between them. Otherwise, the sensor cannot distinguish them as two different individuals. The sensor only sees one continuous beam interruption.

Physical Limitations of Detection

A perfect example of sensor limitation is the “piggyback passage,” where one person carries another on their back. Even the world’s best sensors cannot detect that two people are passing through in this arrangement, because the beam interruption and reconnection is indifferent to this configuration.

The same issue appears when two people walk very close to each other. The difference between good and mediocre gates is the distance required between two people for tailgating prevention to work properly—the longer the required distance, the worse the performance.

Beyond Sensors: Flap Speed and Safety

The sensor logic for tailgating prevention is not the only variable to consider. Modern gate technology enables extremely fast opening and closing times. The flaps themselves are often quite heavy to ensure durability and safety.

This combination means that rapidly moving flaps have significant force. If someone becomes caught between closing flaps, the experience is often quite unpleasant and potentially harmful.

Anti-Pinch Sensor

For this reason, all gate models, both flap gates and speed gates, include anti-pinch sensors. These sensors ensure that the flaps do not close on a person or object standing between them. This is a critical safety feature for preventing injuries.

Unfortunately, this safety feature creates a significant side effect: the anti-pinch sensor weakens tailgating protection in several ways.

In flap gates, a person can intentionally stand between the flaps, keeping the anti-pinch sensor active. As long as this sensor is blocked, the gate will not close, allowing any number of other people to pass through behind the person blocking the sensor.

Speed gates have the same misuse possibility, but they also have an additional significant weakness related to their opening mechanism.

The Speed Gate Closing Delay Problem

As mentioned, a speed gate’s flaps open in the direction of travel, and the flaps close once a person has passed. But the critical question is: at what point do the flaps begin to close?

The answer is that closing can only begin once the person has passed the open flaps. If the flaps began closing earlier, they would close on the person still passing through.

Let’s work through a concrete example. Imagine a speed gate with a passage width of 900 mm. The flaps are approximately 450 mm long (rounded up). The closing sensor can be positioned only at this point or slightly beyond.

To prevent the flaps from closing on an authorized person, the sensor logic must work as follows: the flaps begin closing when the closing sensor’s beam first breaks and then reconnects. First, the person breaks the beam, then they exit its path, and when the connection returns, the closing sequence begins.

Now add a tailgating person to this scenario. In theory, the distance between two people must be at least 450 mm (from the anti-pinch sensor) to the sensor behind the flaps. In practice, even more distance is required.

This means that even the best speed gate can only prevent tailgating when there is more than half a meter of space between people. This is already a significant gap that makes supervision difficult.

Anti-Pinch Override Solution

However, this problem can be circumvented. The anti-pinch sensor can be disabled. When disabled, the gate closes immediately once the person ahead passes the sensor behind the flaps. The flaps then close on anyone following, regardless of how far away they are.

Although disabling the anti-pinch sensor is legal in Europe, several requirements must be met for this to be done legally and safely.

European Regulatory Requirements

Machinery Directive 2006/42/EC (which will be replaced by Machinery Regulation 2023/1230 starting in 2027) requires that machines and automated equipment must not pose crushing, pinching, or shearing hazards. Manufacturers must design safety measures such as:

• Obstacle detection
• Force limitation
• Emergency stop
• Safety distances

Therefore, automatic doors and access gates must also comply with standards EN 16005 and EN 17352, which define a 400 N force limit.

This “anti-crushing requirement” is based on these regulatory requirements and standards.

What Does 400 Newtons of Force Mean?

The 400 newton force limit means in practical terms that a device can push someone, but it must not cause bruising or injury. It is still an extremely unpleasant and startling amount of force, but it remains within safe limits.

400 N of force can be measured with test equipment. In gates, this force level can be adjusted through opening and closing speed settings.

Higher flaps weigh more and must therefore move slower than lower flaps in order not to exceed the 400 N force limit. This is simple physics—the relationship between mass, speed, and force.

Official test methods must be followed, after which new CE markings must be created to certify compliance.

Practical Compromises

The side effect of this approach is that you can no longer have gates that open in 0.1 seconds—that would create too much force. However, such extreme speed is rarely necessary in gym environments.

Flap Gates vs. Speed Gates in Tailgating Prevention

The same 400 N force rule applies to flap gates. In summary, flap gates generally perform better at tailgating prevention than speed gates, especially when the anti-pinch sensor is kept active.

The reason is mechanical: flap gates retract inward, which creates fewer opportunities for the closing delay problem that plagues speed gates. The sensor can be positioned more efficiently, reducing the gap that tailgaters can exploit.

However, when anti-pinch sensors are disabled on both types, speed gates can perform nearly as well as flap gates, since both close immediately after the authorized person has passed the sensor beam.

Modern Camera-Based Detection

Newer technology includes camera systems that can identify two people simultaneously in a monitored area. These systems either prevent the gate from opening or force it to close immediately when multiple people are detected.

These camera technologies are more accurate than traditional IR sensors in many situations. They use computer vision and sometimes artificial intelligence to distinguish between a person wearing a backpack and two people walking close together.

These systems also have their limitations. They can struggle with:

• Simple human behavior (complete automation can be difficult)
• Reaction times (if over 0.1 seconds, logic begins to fail)
• Camera angles
• False tailgating prevention closings

This makes camera-based detection the second-best tailgating prevention method compared to gates with disabled anti-pinch sensors that close at 400 N force immediately after passage.

Choosing the Right Configuration for Your Gym

When selecting gates for your gym, consider these factors:

• Your risk tolerance: How critical is absolute tailgating prevention compared to user comfort? High-security facilities may prioritize prevention; premium gyms may prioritize comfort.
• Your member base: Facilities with elderly members or children should carefully consider force settings. Facilities with primarily young, able-bodied adults may be able to use more aggressive closing.
• Your physical space: Flap gates typically require less space and perform better with anti-pinch sensors active. Speed gates need more space but look more valuable.
• Your regulatory environment: Ensure your chosen configuration complies with local safety standards while achieving your security goals.
• Your budget: Camera-enhanced systems cost more than sensor-only systems. Determine whether enhanced detection justifies the additional investment.

Implementation Recommendations

If you decide to implement gates with anti-pinch sensors disabled to maximize tailgating prevention:

1. Perform proper testing: Test and certify your gate according to the 400 N force limit. Keep documentation of this testing.
2. Update CE marking: Ensure new CE markings reflect the modified configuration and force test results.
3. Adjust speeds appropriately: Work with your supplier to calibrate opening and closing speeds to achieve both good user experience and the 400 N limit.
4. Provide clear signage: Warn users that gates close immediately after passage. Clear communication reduces complaints.
5. Monitor initial deployment: Observe how members interact with the new settings. Be prepared to make minor adjustments based on actual usage patterns.
6. Train your staff: Ensure your team understands how the system works and can explain it to confused members.

Combining Technologies for Best Results

The most effective approach to tailgating prevention often combines multiple technologies:

• Physical barriers (gates) as the primary prevention method, either with anti-pinch disabled and 400 N force limit, or with anti-pinch active and shorter flaps for faster closing.
• Camera systems as secondary detection, particularly effective at identifying unusual tailgating methods like piggyback passage that sensors miss entirely.
• Access control integration that logs every gate passage and flags anomalies where a single credential read results in multiple detected passages.
• Staff supervision during peak hours when tailgating attempts are most likely, with cameras providing video evidence for action.

This layered approach addresses each individual technology’s limitations, creating comprehensive protection against unauthorized access.

Understanding Limitations

No gate system is 100% perfect. Even with disabled anti-pinch sensors and camera systems, determined individuals can sometimes find ways through:

• Credential sharing, where an unauthorized person is the same size and appearance as an authorized member.
• Timing exploitation, where someone learns exact sensor locations and closing delays.
• Physical manipulation, such as holding flaps open or blocking sensors.
• Social manipulation, where someone convinces a member to let them through.

These edge cases are rare, but worth knowing about. The goal is not absolute perfection, but preventing the majority (95%+) of casual unauthorized passage attempts.

Making the Right Decision

Choosing the right gate configuration for your gym requires balancing security needs, member experience, regulatory compliance, and budget constraints.

For most gyms, the optimal configuration is:

• Flap gates or speed gates with anti-pinch disabled.
• Properly tested and certified to 400 N force limits.
• Enhanced with camera-based detection systems.
• Integrated into access control for comprehensive logging.
• Supported by clear communication with members about the system.

This combination provides excellent tailgating protection while maintaining legal compliance and reasonable user comfort.

Final Thoughts

Understanding gate technology’s capabilities and limitations helps you make informed decisions and set realistic expectations. Although modern gates are extremely effective security tools, knowing where they can be exploited enables you to implement additional measures specifically designed to address these vulnerabilities.

Investment in quality gates with the right configuration pays for itself through prevented unauthorized access, improved member satisfaction, and reduced security risks. Choose your system wisely, configure it properly, and support it with complementary technologies to achieve the best overall results.