Understanding the 20+ Lock Functions

Author: Brian Rhodes, Published on Aug 26, 2013

Some suppose all locks are the same but standards existing defining a range of over 20 different lock functions. Understanding them is vital in ensuring the right unit is specified for a job, or else security vulnerabilities or dangers to life/safety can result. In this note we look at lock functions, the ANSI/BHMA Function codes, which types are most common, and the right functions to use when controlling access.

Functions Classified

The 'function' or mechanical behavior of a lock, especially a mortise or cylindrical lever lock, should be specified for an opening. An easy example of different functions in everyday use can be seen when comparing 'restroom/bathroom/WC' locks and 'closet' locks. 

Most bathroom locks include the provision to lock from the inside, preserving the privacy of occupants. However, this same feature is not common on closet doors, simply due to the potential of accidentally locking the door shut and preventing access from the outside.

Function Codes

These properties of locks are identified by codes, and there are over 20 different functions available. Codes are segregated according to lock type, meaning the a mortise and cylinder lock with the same function are coded differently. This simplifies specification writing and ordering, condensing complex interactions to a code.

Before codes were implemented, functions were defined via common labels like 'Passage Functions, or 'Privacy Locks'. However regional and manufacturer variations of those labels are common, and simply identifying these locks by common labels does not guarantee the exact function will be ordered. Because many of the 'old guard' still identifies locksets using these terms, they persist. 

For accurate and precise descriptions, however, the ANSI/BHMA Function codes should be used:

Common Functions

Get Video Surveillance News In Your Inbox
Get Video Surveillance News In Your Inbox

These are 3 of the most common lock functions specified:

  • Office Doors: Most office workers want to lock their doors after hours. The F82/F04 function lets an employee push a button on the back of the lock when they leave, pull the door shut to lock it, and ensure it can only be unlocked by key when unattended.
  • Server Rooms: For higher security applications, the addition of a deadbolt is useful. The F88/F09 "Entrance" function allows for an additional deadbolt to be thrown by keyed locking from the outside of the door, when IT leaves a MDF/IDF. However, when personnel is inside the room, the lever functions like a "Privacy" lock allowing free egress.
  • Break Room: The F75/F01 "Passage" function is ideal for areas using doors for environmental isolations (noise/HVAC) but do not necessarily want them lockable. Areas like Break Rooms are common access, and "Passage" locks assure they aren't inadvertently or maliciously locked from use.

Other applications certainly exist. For example, for a medical storage closet, F86 is a likely choice because the door is locked all the time and can only be opened by a key. The door automatically locks when the door is shut, which is ideal for securing a closet filled with valuable items.  Code F86 also specifies a cylindrical lockset, although if the door was prepped for a mortise lockset, code F07 would provide the same features.

Also, look at Code F84/F05. This function is informally called 'Classroom Function', as they are designed to be installed in schools. These locks always allow occupants out of a classroom regardless if the door is locked or not. However, in order to lock the door, a key must be used on the outside of the room. This orientation has caused some concern in the wake of school shootings, because they potentially expose the teacher or class to danger in order to lock the door. This explains why some products marketed as 'classroom locks' do not specify F84/F05 code compliance, because they can be locked inside the class. While this potentially may be a safer function, it does not meet the formal 'Classroom Function' definition and it is not used.

Specification Callout

Most commercial-grade hardware makes finding lock function easy - generally this is listed on cutsheets, and different product SKUs have different functions, even if the base hardware series is the same. Take this example from Yale:

Finding the right function is straightforward and many distributors will ask you for this information if you do not include it.  Getting the right function ordered is important, because it is difficult or impossible to change this attribute in the field.

Most residential and light-grade commercial hardware does not specify any function code, and is simply sold as an 'office lock' or 'bathroom lock'. These products are configured in only the most common functions and may not be compliant with codes or specifications as a result.

Importance

Simply ordering a lockset because 'it uses a key' and fits within a door is not proper and may be illegal. Certain occupancies outlaw some functions - E2141/F16 "Double Keyed Deadbolt" cannot be used in most group occupancies, while others strictly define required use of others - F93/F15 only on Hotel/Motel doors.

Electronic Access Relevance

Failing to understand lock functions complicate electrified lock hardware selection. For example, if a lock includes a separate deadbolt, an accompanying electric strike may need to upsized to include more that one latch, or more than one strike may be required. Likewise, if a deadbolt is improperly included in a lock in an egress pathway, it could potentially kill or injure people trying to escape.

3 reports cite this report:

Top 5 Biggest Access Control Problems 2016 on Oct 06, 2016
New IPVM survey data reveals integrator's top 5 problems with electronic access control: High Cost Complex Doors and Hardware Lowball...
Classroom Closer Lock Illegal on Oct 28, 2014
Keeping classrooms locked against intruders is one the most urgent security priorities today. With terrible active shooting events in schools in...
Top 5 Access Control Problems on Jul 21, 2014
Here's what integrators say are their 5 top problems with electronic access control: High cost End-user knowledge Lowball Competition Complex...
Comments (3): PRO Members only. Login. or Join.

Related Reports

Batteries For Alarm Systems Tutorial on Jul 11, 2017
Alarm systems use backup batteries in order to continue working if an intruder attempts to disable the alarm by cutting power to the building. In...
Smartcard Copier Tested (13.56MHz) on Jul 05, 2017
Copying 125kHz cards is certainly easy, as our test results showed, but how about 13.56MHz smart cards? Are they more secure? IPVM focused on the...
H.265 / HEVC Codec Tutorial 2017 on Jun 30, 2017
For years, video surveillance professionals have talked about the potential for H.265. Now, in 2017, H.265 is starting to gain mainstream...
Biometrics Pros and Cons For Electronic Access Control on Jun 26, 2017
Biometrics has been long sought as an alternative to the security risks of cards, pins and passwords. While biometrics has improved somewhat over...
Access Control Course Winter 2018 on Jun 11, 2017
The Winter 2018 IPVM Access Control Course is now open; save $50 on early registration. IPVM offers the most comprehensive access control course...
RMR Integrator Importance Statistics on Jun 08, 2017
How do integrators feel about offering RMR / recurring revenue services? For many, their business revolves around RMR, while others see no...
HID Edge EVO Tested on Jun 07, 2017
HID Edge controllers have been one of most common offerings in IP door controllers for years. The new generation is called Edge EVO. We tested...
Access Control AHJ Nightmares on Jun 01, 2017
For access control jobs, a single person can be the difference between finishing a job, costing thousands in extra dollars, and being profitable...
US States Security Licensing Guide on May 30, 2017
In the US, many states require integrators to be licensed to install burglar alarms, CCTV, electronic access control, or all three, and...
Anti-Hack Access Card Shields Tested on May 26, 2017
Keeping your access control card information secure is becoming a big priority, especially since cheaper copiers can hack details easily. Multiple...

Most Recent Industry Reports

Competing Against ADT on Jul 20, 2017
ADT is one of the biggest players in the security industry, with ~$4 billion revenue. In 2017, they were acquired / merged with Protection...
Hikvision Launching Deep Learning Recorders on Jul 20, 2017
Hikvision has become a common choice for super low cost NVRs. Now, Hikvision is aiming to move up market, with deep learning NVRs that claim far...
PR Campaign Exploiting Manufacturer Cybersecurity on Jul 20, 2017
Manufacturers increasingly have a bulls-eye on their back. As cyber security solutions providers grow, they realize a great way to get publicity...
Axis Door Station Tested (A8105-E) on Jul 19, 2017
Axis continues their push into niche markets, especially audio, with network speakers, an IP horn, and video door stations. We bought and tested...
Manufacturer Favorability Guide on Jul 19, 2017
This 120 page PDF guide may be downloaded inside by all IPVM members. It covers our 20 manufacturer favorability rankings and 20 manufacturer...
$8 Billion Utility Georgia Power Enters Surveillance Business Offering Avigilon And Genetec on Jul 19, 2017
Utilities are typically considered major customers of surveillance integrators but one utility, Georgia Power, with $8+ billion in annual revenue...
Knightscope Laughs off Robot Drowning on Jul 18, 2017
A day after a Knightscope robot drowned, Knightscope has issued an 'official statement' making fun of the issue: The implied message is that...
Microsoft Video AI Cloud Services Examined on Jul 18, 2017
Microsoft has released one of the most amazing video analytics marketing videos ever. In it, they detect oil spills, track individual people giving...
Hikvision USA Head of Cybersecurity Exits on Jul 18, 2017
Hikvision USA's Head of Cybersecurity has exited the company. In this note, we review the move, share Hikvision's feedback and examine the...
'Suicidal' Knightscope Robot Drowns on Jul 17, 2017
Knightscope continues its hyper growth, at least when it comes to controversy, this time with a 'suicidal' robot in Washington DC. And here is...

The world's leading video surveillance information source, IPVM provides the best reporting, testing and training for 10,000+ members globally. Dedicated to independent and objective information, we uniquely refuse any and all advertisements, sponsorship and consulting from manufacturers.

About | FAQ | Contact