UL 325 in Plain English: The Safety Devices Every Automatic Gate Needs

An automatic gate is a heavy piece of machinery that moves on its own. UL 325 is the U.S. safety standard for the operators that move it. A companion standard, ASTM F2200, covers how the gate itself is built. Together they exist for one reason: to keep a person from being caught by a moving gate.

Entrapment zones

An entrapment zone is any place where a person could be caught between the moving gate and something that does not move: a post, a wall, a fence, the ground. Every gate has them. The standard requires each one to be protected.

Two layers of protection

Since 2016, UL 325 has called for at least two independent means of entrapment protection for each zone. In practice that usually means the operator's own built-in ability to sense an obstruction and reverse, plus external devices:

• Photo eyes, which stop or reverse the gate when something breaks the beam.
• Edge sensors, which stop or reverse the gate when the edge touches something.

The external devices also have to be monitored. If a required photo eye or edge sensor is missing or has failed, a current operator will not run the gate normally. A gate that has suddenly stopped responding is sometimes a safety device doing exactly what it should.

Four classes of gate

• Class I: residential, serving one to four single-family homes.
• Class II: commercial or general access, such as a gated community, apartment property, hotel or retail site.
• Class III: industrial or limited access, such as a factory or loading dock not open to the public.
• Class IV: restricted access, guarded sites such as secure areas of an airport.

The class decides which operators and which protection devices are acceptable. A community entrance is not held to the same rules as a single driveway.

What an owner should check

• The keypad or intercom is set well back from the gate, so no one can reach the moving gate while using it. The standard calls for at least six feet.
• People on foot have their own entrance. A vehicle gate is not a pedestrian gate.
• Warning signs are posted on both sides of the gate.
• The safety devices are tested on a schedule, not just on the day of installation.