What safety sensors are required on automatic gates?

The standard, translated from committee language

UL 325 is the safety standard for gate operators, and ASTM F2200 is its companion covering gate construction. Together they say, in plain terms:

• Every zone where a person could be trapped, between gate and post, gate and fence, along a slide gate's travel, needs two independent protections.
• Protection one is usually Type A inherent sensing: the operator feels abnormal resistance and stops or reverses.
• Protection two must be external and monitored, meaning the operator verifies the device is present and working every cycle: photo eyes (Type B1) or contact edges (Type B2). A wired sensor that could fail silently no longer counts; since 2016, if the monitored device drops offline, the operator will not run automatically.
• ASTM F2200 adds design rules: no reach-through gaps over 2.25 inches in the travel zone, screened pickets, no protrusions that can snag clothing, and positive stops so a slide gate cannot run off its track.

What this looks like on a real driveway or facility gate

On a typical swing gate we install in the metro, that means one photo eye pair across the opening at roughly knee height, a second pair or a wraparound edge covering the swing path if a wall or fence creates a pinch zone, and edges on the leading edge of commercial slide gates. Vehicle detection loops and exit wands, worth having, are convenience devices, not safety devices; a loop cannot see a child. Warning signs on both sides of the gate are also part of the listing requirements, and yes, adjusters ask about them.

Is any of this "law"? Oklahoma does not run gate inspections the way it inspects elevators. But UL 325 is the manufacturers' listed standard, it is referenced by the International Building Code for vehicular gates, and in an injury lawsuit a gate without compliant protection is nearly indefensible. Several OKC-area insurers now require compliance documentation on commercial gates at HOAs, apartment complexes, and storage facilities before renewing coverage.

Getting an older gate compliant

The typical retrofit on a pre-2016 system: replace non-monitored photo eyes with monitored units, add a contact edge where geometry demands one, verify the operator reverses at proper force, and post signage. What the parts and labor come to depends on how many entrapment zones your gate has; if the operator itself predates monitoring support, a new UL 325 operator is the bigger investment, with class and duty rating setting the number. We evaluate compliance free during any gate repair or maintenance visit, and every new gate opener installation we do ships compliant by default. If your gate already shows symptoms like random reversing, our answer on gates stopping halfway explains how sensor faults present before they become failures.