Institutional Door Hardware and Locking Devices
Think in assemblies
An institutional door is a system: frame, hinge, lock or latch, closer, exit device, coordinator, stops, and seals must work together. Candidates should know ANSI/BHMA A156 grade levels (Grade 1 heavy commercial, Grade 2 standard commercial, Grade 3 light commercial) and that grade is a durability test rating, not a fire rating or a security rating. Know the common lock functions: passage (no locking), privacy, storeroom (key outside, fixed or non-operable inside trim), classroom (key outside, inside lever always free), and vestibule (key outside, thumbturn inside). Handing matters for many mortise locks and exit devices; many cylindrical locks are non-handed. Accessible doors must be usable with one hand, without tight grasping, and within the applicable opening-force limit (commonly 5 lbf for interior doors).
Traps
Questions often swap function and grade, or imply that a heavier grade makes a door fire-rated. They also confuse panic hardware with fire exit hardware: fire-rated openings require labeled fire exit hardware, and ordinary panic hardware may not carry the fire label. Electric strikes work with a latchbolt, not a deadbolt. A closer that fails to latch is usually misadjusted, not defective. Field modifications to a labeled door assembly can void the label.
Worked example
A classroom door must lock from the corridor, permit free egress at all times, and avoid inside key operation. Choose a classroom-function lockset: key outside, inside lever free. Do not choose storeroom function, whose inside trim is rigid and would defeat free egress. Rule of thumb: if the inside lever must always retract the latch, the function is classroom or passage; if the inside trim is fixed, it is storeroom.