BHMA A156-2:2003 pdf download.AMERICAN NATIONAL STANDARD FOR BORED AND PREA SSEMBLED LOCKS AND LATCHES
3.4 Reference to Other Standards. The following Standards are referenced within: ASTM F476 R1996，Security Tests for Swinging Door Assemblies; ANSI/BHMA Standard A156.5-2001 for Auxiliary Locks and Associated Products, ANSI/BHMA Standard A156. 121999 for Interconnected Locks, ANSI/BHMA Standard A156.13 2001 for Mortise Locks，ANSI/BHMA Standard A156.18 2000 for Materials and Finishes, and ANSI/BHMA A156.25 for Electrified Locking Devices. ANSI Standards are available from BHMA，www.buildershardware.com. ASTM Standards are available from ASTM, 100 Barr Harbor Dr, West Conshohocken, PA 19428-2959.
3.5 Values. Required values in this Standard are given in US units. The SI (metric) equivalents are approximate.
3.6 Door and Frame Preparation The lock models described in this standard shall fit the door and frame preparations described in the ANSI A115 Series. Other configurations are permitted to fit special opening templating requirements. See manufacturers' instructions for details.
3.7 Building Codes Certain lock functions described in this standard are not permitted on doors within a means of egress. Consult local authority having jurisdiction.
5.1 In the following lock descriptions, the functions are described using lever trim for brevity and clarity. It is acceptable to use models with knobs， paddles， or handlesets wherever levers are referenced. Where keys or cylinders are referenced, pushbutton code mechanisms are permitted. Some functions may be available with electrical operation in place of mechanical operation. The basic function shall remain the same as described.
F40 Entrance or Store Room Lock. Deadlocking latch bolt is operated by lever from either side except when outside lever is locked by turn button in inside lever . When outside lever is locked, latch bolt is retracted by key from outside or by operating inside lever . Turn button shall be manually rotated to unlock outside lever. At the option of the individual manufacturer, operating the key in the outside lever shall permit the latch bolt to be retracted by operating the outside lever, providing the key cannot be removed in the unlocked position.
F41 Entry Lock. Deadlocking latch bolt operated by lever from either side except when outside lever is locked by push button in inside lever . When outside lever is locked, operating key from outside or operating inside lever retracts latch bolt and releases push button. Closing door does not release push button.
F42 Classroom Lock. Deadlocking latch bolt operated by lever from either side except when outside lever is locked from outside by key. When outside lever is locked, latch bolt is retracted by key from outside or operating inside lever .
F43 Holdback Lock. Deadlocking latch bolt operated by lever from either side except when outside lever is locked from outside by key. Latch bolt is locked in a retracted position by key. When outside lever is locked, latch bolt is retracted by key from outside or by operating inside lever, unless latch bolt has been locked in a retracted position.BHMA A156-2 pdf download.