Sargent 8255 LNL Office Function Mortise Lockset — Commercial Grade | LA Keyway

The Sargent 8255 LNL is a heavy-duty, commercial-grade mortise lockset engineered for office-function applications in institutional, government, healthcare, education, and corporate facilities. Built on the proven Sargent 8200 Series mortise platform, this lockset combines robust mechanical performance with the LNL trim designation and the LA keyway — a configuration trusted by architects, specifiers, and facility managers who demand long-term reliability and compatibility in high-traffic door openings.

Office Function (ANSI/BHMA Function Explained)

The Office Function lockset operates as follows: the latch bolt is normally retracted by lever from either side. A push button or turn on the inside can lock the outside lever, requiring a key for entry — ideal for private offices, consultation rooms, and staff areas where the occupant needs the ability to secure the room from within without permanent key control. Turning the inside lever always provides free egress regardless of the locked/unlocked state.

Key Features & Benefits

• Sargent 8200 Series Mortise Body — industry-recognized heavy-duty mortise chassis suitable for high-cycle, high-traffic commercial doors
• LNL Trim Designation — Sargent's standard lever-on-lever trim configuration; compatible with Rockwood custom push plates for surface cosmetic work when needed
• LA Keyway — Sargent open conventional keyway profile, enabling straightforward key system integration and re-keying in the field
• Office Function — inside push-button/turn locking with free egress from the inside at all times; key resets the outside lever to passage
• Commercial Grade Construction — designed for ANSI/BHMA Grade 1 performance standards common to the 8200 Series mortise product line
• Master Keying Compatible — Sargent 40 Series mortise cylinder supports multi-level master key systems including grand master and construction keying
• Fire Door Compatible — mortise lock format is appropriate for UL-listed fire-rated door assemblies when paired with compliant frames and closers (verify listing for your specific assembly)

Typical Applications

• Private offices and executive suites in commercial office buildings
• Government and federal facility interior secured offices
• Healthcare consultation and staff rooms
• Educational administrative and faculty offices
• Military and institutional applications requiring push-button office lockdown capability

Technical Details

For facilities requiring compatible trim accessories — including custom stainless steel push plates prepped for the LNL configuration — Rockwood custom push plates are a proven solution for covering surface imperfections around 8200 Series mortise lock installations. Contact our team for specification assistance or to request a quote on comparable mortise lockset alternatives from preferred lines including Corbin Russwin, PDQ, and Hager.

The Sargent 8255 LNL is a premium Grade 1 Heavy-Duty Mortise Lockset designed to provide flexible security for professional office environments, administrative suites, and commercial buildings. As a flagship model in the Sargent 8200 Series, it is engineered to withstand extreme physical abuse while offering the legendary reliability of a heavy-gauge steel mortise chassis. The 8255 Office Function (ANSI F04) allows for versatile access control, enabling the door to be locked or unlocked via the stop works (toggle) on the lock face or by the exterior key.

Versatile Office & Entrance Function (ANSI F04)

The 8255 function is the industry standard for private offices where users need to toggle between "open" and "restricted" access throughout the business day.

• Dual Locking Control: The outside lever is made rigid (locked) or operative (unlocked) by the stop works (toggle) located on the front of the lock body.
• Keyed Entry: When the outside lever is locked, entry is gained only via a physical key using the standard LA Keyway.
• Constant Free Egress: Regardless of the locking status, the inside lever always allows for immediate exit, ensuring full compliance with NFPA 101 Life Safety Codes.

Architectural Excellence: The LNL Trim Design

The LNL design combines the contemporary L-Lever with the traditional LN-Rose, providing a sleek, professional aesthetic that complements modern office interiors.

• ADA Compliance: The linear L-Lever is ergonomically shaped for easy operation without tight grasping, meeting all ADA accessibility requirements.
• Lever Sag Prevention: Equipped with high-carbon steel spring cartridges that ensure the levers remain perfectly level and horizontal, maintaining a professional look for the life of the building.
  
• LA Keyway Standard: This lockset comes with a 6-pin brass cylinder in the popular Sargent LA Keyway, making it easy to integrate into existing master key systems.

Key Product Features

• ANSI/BHMA Grade 1 Certified: The highest industry rating for mechanical strength, cycle life, and security.
  
• Office/Entrance Function (F04): Features a face-mounted toggle for easy locking management.
  
• Fire Rated: UL/cUL Listed for use on 3-hour fire-rated doors, essential for corridor and office safety.
  
• High-Security Latching: Features a 3/4" throw stainless steel anti-friction latchbolt for smooth operation and increased resistance to forced entry.
  
• Field Reversible: The non-handed chassis is easily adjusted in the field to accommodate any door handing.
• Vandal Resistant: Built on a 12-gauge heavy-duty wrought steel lock case that is zinc dichromate plated for maximum corrosion resistance.

Technical Specifications

Ordering & Installation Information

The Sargent 8255 LNL is designed for precision fitment in standard commercial door preparations. While the lock is field reversible, providing the hand of your door ensures the unit arrives ready for immediate mounting.