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American National Standard for Bored Locks and Mortise Locks with Ligature
Resistant Trim
Standard ANSI/BHMA A156.34-2019 defines requirements and test methods for ligature resistant trim on bored locks and mortise locks. These requirements apply to the exposed parts of the lockset on the face of the door in the closed position only. For further information, consult the full standard, ANSI/BHMA A156.34 for Bored Locks and Mortise Locks with Ligature Resistant Trim.
BHMA has created this series of Hardware Highlights to provide useful, accessible information about builders hardware for architects, specifiers, builders, building code officials – anyone with an interest in devices that hang, control, secure, and trim the doors. BHMA is the trade association which represents almost all of the North American manufacturers of builders hardware. One of its main activities since 1983 has been the development and maintenance of ANSI-approved standards for 35 separate product categories.
Product Performance: Purchasers of locks with ligature resistance certified to A156.34 (http://buildershardware.com/cpd) can be assured products will perform to their expectations.
Below are an explanation and some examples of the evaluations conducted for certification:
Attributes such as the force to retract the latch and force to close the door are measured to ensure ease of egress and smooth closing. The forces to open the door vary by the type of Lock – compliance to the respective standards is required.
Building products are expected to last a long time, and builders hardware is no exception. Grade 1 locks, for example, must pass a rigorous test through one million cycles of opening and closing with a 10 pound axial load applied.
Grade 2 Example:
The force gauge does not exceed 11 lbf in any direction from the attachment point within the shaded area, or no attachment at all.
Builders hardware provides several attributes that are essential to building safety and performance, including egress and fire protection. BHMA locksets are designed to comply with all applicable requirements. For example, hardware for fire doors is evaluated and listed to UL 10C by an accredited third-party testing laboratory.
There are various types of trim which meet the ADA and A117.1 requirements for operable parts to be “operable with one hand and shall not require tight grasping, pinching or twisting of the wrist.” Lever or paddle type trim meets these stipulations, while knob trim should be avoided for accessible routes. In addition, BHMA certified hardware must comply with the operational forces in their respective standards, which have been shown to be suitable for accessible applications.
Locks and latches contribute to building sustainability through their verified durability, as well as material characteristics such as recycled content and recyclability. The reliable closing and sealing of openings can also contribute to energy conservation. BHMA has developed Product Category Rules, which will further define sustainability requirements and guide life cycle assessments and environmental performance declarations.