UL 325 Standards for Safety
When installing motorized gates and barriers in commercial and residential areas, safety is always the top priority. Like any other outdoor installation of motorized equipment, electrical safety standards must be dealt with to prevent injury or death hazards, as well as the prevention of fire and electrical threats. It is vital for installers and code authorities to thoroughly understand how these systems are to be installed with safety and code compliancy in mind. To address these safety issues, US Consumer Product Safety Commission (CPSC) worked with Underwriters Laboratories, Inc. (UL) to produce a strict set of safety standards to reduce these risks, thus leading to the UL 325 Safety Standard being established to make a basic set of safety guidelines for proper installation, service and operation of motorized equipment, specifically opening and closing applications rated 600 volts or less.
UL 325 Gate Operator Safety Standards
The UL 325 Standard allows all applicable products to be tested at a nationally recognized testing laboratory. This standard also:
- Contains the criterion for the qualifying characteristics with which products must comply with to be documented (Listed) and marked (Labeled) under the requirements of the UL 325 Voluntary Listing and Labeling Program.
- Pertains to specific methods of safety testing and regulations.
- Cover installation of products under the requirements of the National Electrical Code.
- Address fire and electrical safety, as well as the overall safety of the public.
Gate operators that are intended to control vehicular entrance and/or exit are held to the highest standard when it comes to testing the requirements of the UL 325 Safety Rating. These gates may be the swinging, sliding, or barrier types. Vehicular gate operating systems are required to have provisions, or be supplied with at least one independent primary and one independent secondary means to protect against entrapment, however barrier arm operators do not require such as long as they are not intended to move closer than two feet from an object, provided they do not have pinch points between moving parts.
Certified vehicular gate openers will include a UL Listing Mark, the word “LISTED” and “Gate Operator” or other appropriate product name shown in the individual Listings. Gate operators are also marked to specify the intended Classes use, as well as the maximum rated closing force.
Following the UL 325 Safety Standard, a classification system was established for basic groupings of the various types of systems. There are four different classifications for gate operators:
Class I – Residential Vehicular Gate Operator
A vehicular gate operating system that is intended for use in homes (ranging from one to four single family dwellings, garages or parking areas).
Class II – Commercial/General Access Vehicular Gate Operator
A vehicular gate operating system that is intended for use in commercial locations such as multi-family housing units (five or more single family units, hotels, garages, retail stores or other buildings that service the public).
Class III – Industrial/Limited Access Vehicular Gate Operator
A vehicular gate operating system that is intended for use in industrial locations (factories, loading dock areas, or other locations not intended for public use).
Class IV – Restricted Access Vehicular Gate Operator
A vehicular gate operating system that is intended for use in guarded industrial locations (airport security areas or other restricted access areas that do not service the public, in which unauthorized access is prevented by security personnel).
Required Primary and Secondary Entrapment Protection:
The types of required entrapment protections vary depending on the gate classification and the intended uses and movement. This protection can include the following methods, among other protection standards:
- Essential entrapment protection system that can stop and reverse the gate within 2 seconds.
- A non-contact photoelectric sensor or the equivalent that can stop and reverse the gate within 2 seconds.
- A contact sensor (edge sensing device) that can stop and reverse the gate within 2 seconds.
- A built-in adjustable clutch or pressure relief device that will stop the gate upon sensing an obstruction from any direction and not result in a closing force of more than 10 percent higher than the initial setting required to stop the gate, which also cannot exceed 40 lbf.
- An actuating device that requires continuous pressure to maintain opening or closing motion of the gate. Once the pressure is removed, the gate must cease to move.
- An audio alarm.
Installers and code authorities must be aware that the ultimate safety of the system is reliant on proper installation. Special attention needs to be given to the following:
- Code authority consultion before installation.
- Proper verification that the Gate Operator Class is appropriate for the intended application.
- Installation should be performed by a qualified installer, strictly following the manufacturer’s instructions.
- Extra consideration and care should be exercised during installation to make sure that the recommended safety devices are properly installed.
Why Should This Concern You?
Every party involved in the operation of motorized opening and closing systems should be aware of these standards to provide the highest safety and liability prevention available. These parties include every entity involved including the manufacturers, engineers, designers, dealers, installers, technicians, and end user – all of whom are responsible for the safety of these systems. These standards affect how systems are to be specified, installed, serviced, and used. If all parties follow these standards, maximum safety will be obtained.