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Experiencing the New Von Duprin Chexit

Chexit door label from Chexit installation instructions.

Von Duprin Chexit door label from Chexit installation instructions.

Last year Von Duprin began shipping Chexit self-contained delayed egress exit devices that are motorized instead of solenoid driven.  Since they are motorized, the new Chexits draw less current and will probably be more reliable than the previous solenoid-driven version. This means a less serious, less expensive power supply, less need for high capacity, high gauge, high cost wire and greatly increased workable wire run distances – all good things.

The new Chexit will do everything the old Chexit did, including release of the outside lever trim when the external inhibit function is activated by access control or another external switch.  That remains a way to get access control out of a Chexit by simply adding a blank escutcheon or other unlocked outside trim to the Chexit exit device.

As of this writing Exit-only function Chexit devices were being shipped less the part number 040193-00 cable used to connect the E996L to the Chexit PC board.  The cables are only provided if you order the Chexit from the factory with trim, but that is okay as long as you want to use no trim or non-electric trim.  Electrified trim is a means to provide fail secure access control from the trim side, so if the fire alarm goes off and powers down the Chexit, the fail secure electrified trim will stay locked.  Entry can still be gained by key.

On another note, recently I was involved in an application where the installer was replacing a mortise exit device and wanted delayed egress from the push side and free ingress from the pull side.  Luckily it was a mortise device, so all I had to do was provide a Chexit mortise exit device with blank escutcheon (passage function) trim because THE MORTISE LOCK ACTS INDEPENDENTLY FROM THE CHEXIT ON THE TRIM SIDE. Cool. 🙂

Bear in mind that  the Chexit remains active while people are using the passage function trim to get in, so if they happen to depress the touch bar, say by bumping it up against the wall for two seconds, they may activate the Chexit alarm.   Von Duprin Tech Support suggested a palm switch on the trim side to activate the inhibit circuit in the Chexit while a person enters from that side.

 





It was fun, easy, and I looked like a … Hardware Genius.

Choosing a Delayed Egress System: Self-Contained, or Built from Components?

Delayed egress is a process that delays unauthorized exit from a space while complying with NFPA 101 life safety code.  Use of this process is strictly regulated with the help of building inspectors and fire marshals across the United Sates.  With that in mind it is always a good idea to get your local AHJ (Authority Having Jurisdiction) on board whenever you are planning to install delayed egress on an opening.

When you beginning planning your delayed egress system you will find that many systems on the market are self-contained.    These could be delayed egress electromagnetic locks or electrified delayed egress exit devices.

Here are some examples of self-contained delayed egress maglocks:

  • SDC 1511S
  • Schlage Electronics M490DE
  • Dynalock 3101C

Here are some examples of self-contained delayed egress exit devices:

  • Detex V40 EE
  • Von Duprin Chexit
  • Sargent Electroguard

delayed-egress-anatomy
Almost all delayed egress systems are made up of the same components:

  1. Delayed egress timer and relay logic board
  2. Initiating Switch (to initiate the delayed egress process)
  3. Audible alarm
  4. Signage
  5. Reset switch
  6. Optional bypass switch
  7. Fire Alarm interface
  8. Power supply
  9. Locking device

Therefore it is possible to construct a custom delayed egress system from components.  Later I’ll talk about why you might want to choose a built-from-components delayed egress system instead of a self-contained one.   The following sections describe each part of a built-from-components delayed egress system.

Delayed Egress Timer and Relay Logic Board

This board is UL Listed and specifically designed to perform all delayed egress functions in compliance with life safety code.   Here are some examples of component boards for delayed egress:

  • Securitron XDT-12 or XDT-24
  • Seco-Larm SA-025EQ

The board is the brains of the delayed egress operation.  It has contacts to wire in switches for delayed egress initiation, fire alarm interface and system reset, timers to control nuisance and egress delay, and relays to control locks and notify external devices.

There are also delayed egress controllers that offer more features.  The following may include the delayed egress timer/relay board and some other required feature(s) such as the initiation switch or the audible alarm.

  • Alarm Controls DE-1
  • Security Door Controls 101-DE
  • Securitron BA-XDT-12 or BA-XDT-24

Initiating Switch

The switch that initiates the delayed egress process shares several characteristics with any request-to-exit switch.  To comply with life safety regulations it must require no prior knowledge to operate; it must require no more than one motion to operate; and it must be placed in relation to the door according to life safety standards in your local jurisdiction.  I think that the best possible initiation device is a mechanical push bar with a switch, such as the Adams Rite 8099-M or the Securitron EMB.  In a panic situation it remains obvious that to get out, one must push on the bar, and because it is mechanical it is unaffected by power outage.  If it is wired to open the contact when pushed, if the wires leading to it are cut it will initiate the delayed egress process.

In rare circumstances where it might be permitted, the locking device might be a fail safe electrified mortise lock that is locked on both sides, inside and out.  Then the initiation switch might be a palm switch next to the door.

Audible Alarm

The mandatory audible alarm sounds for 15 seconds before the delayed egress controller releases the locking device to allow exit.  It’s loudness must be between 81 and 88 decibels.  In some jurisdictions the alarm must be manually reset at the door; in others it may be self resetting via timer or door position switch.  Yet another reason to have a heart-to-heart talk with your local AHJ when designing your delayed egress system.

Signage

The wording on the mandatory sign must comply with life safety code.  There are minor variations in wording.  I suggest buying a sign that is part of a delayed egress system.  The sign that comes standard with the Von Duprin Chexit is readily available as a separate part.

Reset Switch

As mentioned in the “Audible Alarm” section above, a delayed egress system reset switch located at the door is mandatory in some jurisdictions.  Check with your local AHJ.  In some jurisdictions delayed egress systems are allowed to be reset by remote switch or other means, such as a door position switch.

Any kind of momentary contact switch will do the reset switch job, but delayed egress system reset switches located at the door almost always require some kind of security to prevent unauthorized resetting.   Standalone keypads or key switches are often used for this purpose.  Delayed egress systems can also be integrated into existing access control.

Optional Bypass Switch

Not required but often needed, the optional bypass switch allows authorized personnel to exit without triggering the delayed egress system.  Again, any momentary contact switch will do, but usually some security is required.  If you are using a keypad as the system reset switch and the keypad has more than one relay, you can program the second relay to be the bypass switch.

If access from the exterior side is required a bypass switch is required on that side.  Sometimes security is not needed from the exterior side.  In that case a simple momentary contact pushbutton will do the job.

Fire Alarm Interface

The mandatory fire alarm interface allows enables fire alarm panel to deactivate the delayed egress system immediately in the event of a fire alarm.  This is an integral part of the life safety code that allows a delayed egress system to exist.  Therefore, if your building does not have a fire alarm panel, without special permission from the local AHJ you cannot have a delayed egress system.

Power Supply

All delayed egress systems I have had experience with run on low voltage power that comes from a low voltage power supply.  Generally delayed egress systems require regulated and filtered power at 12 or 24 volts.  Delayed egress controllers draw very little current, but as will all electrically operated systems, the current draw of all attached devices must be taken into account when selecting a power supply.

Locking Device

The locking device must be electrically locked and fail safe from the egress (interior) side.  The most frequently used locking device in a component based delayed egress system is the electromagnetic lock.

Why Build a Delayed Egress System?

Why would you put together a delayed egress system from components when there are so many good self-contained systems?

  1.  To Save Money.  Piecing together a delayed egress system can be significantly cheaper than buying a self contained delayed egress system.
  2.  To take advantage of existing hardware.  For example, if there is already an electromagnetic lock on the door, adding the other components is relatively easy.
  3. Conditions at the door prohibit use of a self contained delayed egress system.  For example, door size or the presence of existing hardware may require the installer to seek a more creative solution.

 





Bottom line, unless you have a prison, you cannot lock ’em in.  Well, not without permission.  🙂

How to Order Door Hardware for Small Commercial Projects

This article is for facilities or property managers who need to buy hardware for change-of-use projects in which there is no architect involved.

On larger projects that involve build-outs or new construction, along with the doors architects usually specify the door hardware, often with the help of an Authorized Hardware Consultant (AHC).  On smaller projects wherein the services of an architect are otherwise not required, hardware choices often fall to you:  the facilities or property manager or owner.  This article will provide language and concepts that will facilitate communication between you and your hardware dealer and/or installer.

Get Good Advice

If you do not already have one whom you do business with, choose a qualified hardware installer.  I may be a little biased, but I think locksmiths make the best hardware installers.  Some contractors also have hardware installation specialists on staff who are qualified to do the work.  Experienced and qualified hardware installers can help answer your questions as you tackle this project.

Specifying the wrong hardware can be expensive, so your hardware choices can be very important.  In addition to your hardware dealer or qualified installer, your local building inspector and fire marshal can be invaluable sources of information.  They will be able to tell you, for example, if a particular door needs panic hardware and/or fire rated hardware.  Your qualified installer should also be able to help with these choices, but if there is ever a choice you are not sure of you can always consult these governmental authorities.

 

Know Your Doors

Number Your Doors 

Assign each door a number.   Stick a label with the door number on every door on the edge on the hinge side, just above the top hinge.   List the door numbers across the top of a spreadsheet.   Under each door number enter the existing hardware, door dimensions and other characteristics as discussed in the following sections.

Existing Hardware

Do a survey of the property and catalog every door, hinge, kick plate, door closer and lock.  Base your notes on the following categories of information in this article and you should be able to answer most questions your hardware installer may have without them having to visit.  You get two benefits from this:

  • Knowledge of what you have and what you want
  • Savings of time and therefore, money

List every hardware item on every door.  Be sure to open the door and look on both the inside and the outside.  Below is an illustration of some of the different kinds of hardware one may find on a door.

hardwaredoors

Don’t forget the wall or floor stops.

You may ultimately decide to reuse your existing hardware if it suits your intended use of the space and is in good working order.  You may need to rely on your hardware installer to help you determine what may be kept and what should be discarded.

Fire Rated vs. Non Fire Rated

Fire rated doors are designed to resist the spread of a fire within a structure.  Fire rated doors get their fire rating from Underwriters Laboratories and have a UL label on them showing the fire rating.  Only fire rated hardware can be used on fire rated doors if the fire rating is to be maintained and your project is to pass inspection.  Interior stairwell doors are always fire rated.  Other interior doors often may be fire rated as well.  Check all doors for fire labels; consult your local Fire Marshal if you are unsure.

thicknessLocks for fire doors are UL listed as such and must positively latch whenever the door is closed.  Without exception, fire rated doors must be closed and positively latched in the event of a fire.   Therefore fire rated doors always have a door closer and some kind of UL listed latching device, such as a mortise lock, fire rated exit device or UL listed cylindrical lock.

Non-fire rated exit devices may have a “dogging” mechanism that keeps the push bar pushed in so that the latch(es) remain retracted.  Usually this is apparent as a small hole in the bar where a hex key can be inserted to dog the device down.  Sometimes the dogging mechanism is operated by a key cylinder.  If your device is equipped with any kind of dogging it is not a fire rated device.

Fire rated doors must be equipped to self-close.  This must almost always be accomplished through the use of a door closer.
Exterior doors are not usually fire rated, or if they are labelled may not have to comply with the positive latching rule.   Consult your local fire marshal or building inspector if you have any question.

Failure to comply with fire and life safety code can have expensive consequences so use extra care.

doordimensionsDimensions

Accurate dimensions of door and frame are vital when choosing door hardware.  Here are some common door measurements:

  • Width
  • Height
  • Thickness
  • Reveal
  • Stile width
  • Rail height

Door Width and height can be important when you are choosing a door closer or an exit device, and vital in complying with the American Disability Act (ADA) that requires openings to provide 32 inches of passage clearance.   This includes the space occupied by the open door.

reveal

The Reveal.

Door thickness can be important when ordering door closers, exit devices and locks.  Reveal dimension is important for certain types of door closer installations.

As shown in the illustration below, the stile is the vertical part of a door that is made up of the components, stile and rail, whereas the rail is the horizontal part.  Most stile and rail type commercial doors are aluminum, although more and more of them are Fiber Reinforced Plastic.

 

alumstileandrail

Stile width is important when ordering locks or exit devices.  Rail height is important when ordering door closers or electromagnetic locks.

Photos of doors are also good to have, but are not a substitute for accurate measurements.  

Handing

The “hand” of a door describes the direction it swings in relation to its hinges.  If you imagine yourself being the hinge, and your right hand is on the door while your left hand is on the frame (like the person in the picture), the door is Right Hand.

handingwithhands

His right hand shows that this is a right hand door.

 

T-handing

Doors are always Left Hand (LH) or Right Hand (RH) however some locks can be Left Hand, Right Hand, Left Hand Reverse (LHR) or Right Hand Reverse RHR).   “Reverse” means that the locked side of the door is the pull side.  If a ‘reverse’ handed lock is installed on a Right Hand door, the lock is said to be Left Hand Reverse.  If it is installed on a Left Hand door it is said to be Right Hand Reverse.

All exit devices are reverse handed.

Location

The location of a door affects the hardware that can be installed on it.  For example, locking exterior doors in commercial facilities designed to accommodate a given number of people are usually required to have panic hardware – that is, an exit device with a push bar that goes across the door, the actuating portion of which must measure at least half the width of the door.   Most exit devices easily comply with this requirement.

All life safety code compliant buildings have a “path of egress,” that is, a clearly marked escape route in case people need to get out of the building in a hurry if, for example, the building is on fire.   Electrically lit exit signs are usually required to be placed along the path of egress to show people where they need to go.  Doors located in the path of egress are referred to as “egress doors” and are almost always required to swing in the same direction as the path of egress.

As previously discussed, while exterior doors are rarely fire rated, interior doors are often fire rated.  Fire rated doors need to be positively latched in the event of a fire, so if you are using exit devices with electric latch retraction, the latches must be extended in the event of a fire; if you are using fire rated electric strikes, they must be locked in the event of a fire.  Usually this is achieved (in both cases) through the use of a fire alarm interface relay, which is a device by which the fire alarm system can interrupt power to locking devices in the event of a fire.

Stairwell doors are unique in that not only are they fire rated – so they must be positively latched in the event of a fire – they must also usually be unlocked in the event of a fire.  This is all fine and good if locking the stairwell doors is not required, (passage function mortise or Grade 1 cylindrical locks or fire rated exit devices with passage function trim will all do the job just fine) but when access control is required the range of choices is limited.  Electric strikes cannot be used, but electrified fail safe mortise or cylindrical locks can be used as well as electrified fail safe exit device trim.  All such devices must be automatically unlocked by the fire alarm system as described above.

Composition

What is your door made of?  Doors made of different materials often require different kinds of hardware.

  • If a magnet is attracted to your door, then it is a hollow metal door.  Hollow metal doors are perhaps the most popular doors to be used in commercial facilities.
  • Is your door mostly glass with a relatively slim frame around it?  Then it is probably an aluminum storefront door.
  • Wooden doors are also common and used in all of the applications as hollow metal doors.
  • FRP (Fiber Reinforced Plastic) doors are also becoming more popular all the time, and they are available in different configurations to accommodate almost every application.

Lock Prep

Commercial hollow metal or wood doors are usually prepped one of three ways:

  • Blank – no prep whatsoever
  • 86 Prep – prepared for mortise clock
  • 161 Prep – prepared for cylindrical lock, 2-3/4 inch backset, with ANSI standard 4-7/8 inch tall strike

BacksetThe 161 Prep is a prep for a cylindrical lock.  It can be identified by a 2-1/8 inch diameter hole (called the ‘bore’) centered 2-3/4 inches from the edge of the door and a an opening in the edge of the door that is 2-1/4 inches high by 1-1/8 inches wide.  Centered in this edge prep is a 1-inch diameter hole for the latch.   The distance between the edge of the door and he centerline of the door is called the “backset.”

Most Grade 1 cylindrical lever locks have through-bolts that must be drilled outside the diameter of the 2-1/8 inch hole.  Then it is said that the lockset has through-bolts “outside the prep.”

Aluminum and glass storefront doors have specialized hardware.  Most hardware designed for other kinds of doors will not fit on a narrow stile storefront door, but may fit on a wide stile door.  Aluminum doors most commonly come with a prep for an Adams Rite MS1850S deadbolt.  Adams Rite offers other locks and exit devices that fit this same prep.

Locks

Lock Functions

There are many, many lock functions, but here are a few of the most common.  Common lock functions often correspond to door use or location.  Office doors are usually equipped with office function locks:  locks that can be locked from the outside only by key, but can be locked from the inside by pushbutton or turn knob.   Classroom doors get classroom or classroom security function locks.  Single occupant bathrooms get privacy locks and/or occupancy indicator deadbolts.  Janitors’ closets and storerooms are fitted with storeroom function locks.  Non-locking doors get passage function locks:  locks that are always unlocked from both sides.

Wherever you use an electric strike you will probably also use a storeroom function lock.  You will also need a door closer.

In order to comply with ADA requirements, all locks should be equipped with lever handles.  Check with your local building inspector to make sure your choice of lever design is ADA compliant.

Keying

Even if you intend to use electronic access control, your locks will probably still have keys.   To determine which key will open which door, determine who will have access to that door.  The more doors that are opened by the same key, the greater the convenience and the greater the security risk.  Therefore key control must go hand in hand with keying.

If you are only using keys for access and have an existing master key system, it is helpful to have access to the bitting list for your system.  If you do not have it on site, perhaps the locksmith who created the system still has it.  With the bitting list a locksmith can determine whether it is possible to add more locks (more changes, s/he would say) to your system and may be able to safely add changes without creating keys that open more than one door in the system.

There are software programs on the market that create master key systems, but unless you are a locksmith I suggest you leave the keying (and the software) to a locksmith.

If you are creating a new group within an existing system – for example, you are head of maintenance at a small college that is opening a new department within an existing building – and you already have an institution-wide master key system in place, you may want to create a sub-master key that opens all the doors within this new group.  This will be convenient, but remember to keep such a key in a safe place and be careful who you give it to.  This is the essence of key control.
In addition to your new sub-master key, it is wise to key doors alike only when they will always be opened by the same people.  For example your utility closets may only be opened by your maintenance staff, so you may want to key all your utility closets alike.  They will also be accessible via the sub-master and the existing master key.

The important principle here is to realize that you put locks on door to keep people out and you give keys to people so that they can get in.  Key control is making sure the people you want to keep out don’t get the keys and the people you want to let in do.

In addition to keying software, key control software is also available.  Usually, however, if you are creating a small group of, say, 25 doors or less, a simple spreadsheet or even a hand written ledger may be all you need to keep track of your keys.

Access Control

The same principle applies to access control, but the practice of access control is much simpler.  In access control you simply give everyone their own unique credential (magnetic stripe card, proximity card, pin code, etc.).  The access control system keeps track of who accesses which door and when.   You can have one credential open all the locks, but then you have to be careful who you give that credential to.  It acts as your master key.

One advantage of access control is that you will be able to tell who accesses what door and when.  If your project will house sensitive or expensive equipment or intellectual property, you may want the ability to keep records of the movements of people who have access to it.

Another advantage of access control is that you can change who has access to a given door without changing the lock.  Often one can add and delete users from any given door right from one’s desk using the access control system software.

Other Door Hardware

Hinges

There are many, many varieties of hinges.  On small projects I have found that the hinges and doors are often reused if they are in good working condition.  But hinges must be replaced if they are damaged or worn.  Take the time to identify and learn about the hinges on your job.

The overwhelming majority of hinges in the United States are one size, finish and configuration.  They are 4-1/2 inches high and 4-1/2 inches wide; they have ball bearings to reduce friction and increase life; and, by far, most of them are satin chrome plated steel.  They are full mortise hinges because both leaves are cut in:  one is cut (or mortised) into the frame and one is cut into the door.  These are called “butt hinges,” I’m not sure why.

The correct way to measure a hinge is [height] by [width] as shown in the illustration below:

HingeMeasure

You can check out my full article on hinges here.

Door Closers

I write of door closers at length elsewhere.

For your small commercial project you need to know how you want each door closer to behave on each door.  There are some limitations.  For example, you cannot have door closers with hold-open arms on fire rated doors unless they are electric and so can be released by the fire alarm.   If you restrict your use of hold-open hardware to exterior doors you will be completely safe from code violations, but this is not always practical.   Remember, therefore, that hold open hardware on fire doors must be releasable by the fire alarm panel and you should be okay.

As mentioned earlier, the reveal dimension of your header can affect whether or not you can use a closer mounted in top jamb configuration.  Other opening idiosyncrasies – arch top doors, transoms, odd widths – can also affect your choice of door closer.  My best advice is to take good measurements and consult with your qualified hardware installer.

Auto Operators

Also called power operators or automatic door openers, auto operators are growing more in demand every year as we move toward a more inclusive society.   These devices are potentially dangerous if specified or installed incorrectly.  Therefore if you need an automatic door opener your best bet is to hire an automatic door company.   Your second best bet is to have your qualified hardware installer choose and install a low energy power operator that is designed to exert less force, thereby presenting less of a potential hazard.

Auxiliary / Decorative Hardware

On most openings one finds a door stop.   The purpose of the door stop is usually to prevent the hardware on the door from hitting and damaging the wall, but sometimes it is used to prevent the door from opening too far.   There is a great variety of door stops designed to accommodate different conditions.

In addition to door stops there may be kick plates or other protection plates, door viewers, lock guards, surface bolts, metal numerals or letters, mail slots, or various and sundry other hardware items to serve a myriad of purposes.  Most of these items are fairly self explanatory.

Kick plates, armor plates and protection plates are measured like hinges:  height x width.

Review 

Once you have assembled the information and organized it by door number, review it as best you can for accuracy and completeness.   You can always go back and check if you have to.

  • Door dimensions, handing, composition and location
  • Whether or not doors are fire rated or non-fire rated
  • List of existing hardware and/or lock preps
  • Lock functions, design, finish and keying (and access control)
  • Hinge sizes and finishes
  • Door closer functions and finishes
  • Auto operators, if any
  • Auxiliary hardware required

Armed with this information you will be on good footing when you discuss the job with your qualified door hardware installer.  Best of luck with your project.

Overview: School Security Hardware

11line

Sargent 11-Line Cylindrical (bored) Lockset

Security in our elementary and secondary schools has become much more important. Schools across the country are implementing lockdown procedures in case of emergency. Lockdowns are achieved through the use of locks, and new lock functions have been developed for use in concert with existing lock functions to answer the need for increased security.

Classroom Security Locks

A regular, traditional classroom function lock is unlocked and locked from the outside by key and the inside lever is always unlocked, allowing free egress. The problem with this function from a lockdown point of view is that, in order to lock the door, the teacher must open the door to lock it, exposing themselves and potentially their students to danger as they do so.

All major lock companies are either developing a classroom security function or assigning that application to one of their existing functions. Basically, the principal is this: in the event of an emergency the teacher can lock the outside lever handle of the classroom door from inside the classroom, thereby securing the safety of the students without endangering themselves. The inside lever remains unlocked allowing free egress. When locked, entry from the outside is by key only.

Some companies have developed classroom security function locksets in which the outside lever can be locked or unlocked with either the inside key or the outside key. This allows the teacher to continue to use the lock as a traditional classroom lock unless an actual emergency develops.

Click here for a complete description of classroom security function in a mortise lock.

 

Electric Lock Down Systems

Some school districts have opted to lock down their perimeter doors with delayed egress systems. Delayed egress systems are a way of locking exterior entrance doors from both sides while allowing for emergency egress.

Quest for the 24-Inch Exit Device with Electric Latch Retraction

Yale7100I had a lot of fun recently trying to meet a customer’s requirement for a 4-foot by 7-foot pair of doors in a hospital that needed to be fire rated and automated.   I found that Corbin and Yale (sister companies whose exit devices are almost identical) offer fire rated surface vertical rod exit devices with electric latch retraction that meet this need.   The installer will be able to put some kind of little power operator on each 24-inch leaf of this four foot pair and cram two fire rated surface vertical rod devices onto these same narrow leaves.  Doubtless it will look odd, but it will work.

Admittedly the whole idea is a bit dubious.  True, by having both leaves opened simultaneously by power operators will provide amply more than the minimum 32-inch clearance demanded by the American Disabilities act, but if anyone manually opens either leaf it certainly will not.

Sargent and Von Duprin offer 24-inch fire rated exit devices, but neither offer them with electric latch retraction.   It is unfortunately necessary to call these companies’ tech support lines in order to verify this information, since their price lists both show 24-inch possibilities without disclaiming the electric latch retraction option.  Neither the Sargent nor the Von Duprin has a note to say the 24-inch device is not available with electric latch retraction that I could see; if that is in fact the case, the buyer is left to beware the exit device order that bounces back because it was ordered with options that are mutually incompatible.

It’s good advice anyway to always call the manufacturer’s tech support whenever there is a question.  Waiting on hold is a lot better than storing thousand-dollar exit devices that didn’t work out on the job.

Note:  A reader named Rick writes in with this about Sargent electric latch retraction:  “Tom, I just stumbled across your site this evening, while doing a search for Fail Secure mag locks of all things (IR says there is one).  But I saw your latest article on latch retraction units and had to clarify the Sargent restrictions. These can be found within the catalog pages, specifically the page showing the 56 option (toward the back). It says:

         MinimumDoorWidths:
              -Wide Stile Door 28″
              – Narrow Stile Door 26″
Thank you, Rick, for this bit of info.  I should add that it is always good to check all the literature at your disposal for any information you are looking for.  Some manufacturers have more detail in their price list than in their catalog, and others vice versa.  Thanks again.


The Double Door Rim Strike – A.K.A. “The Pocket Ripper”

pocketripperOne of the hallmarks of bad hardware choices is the “pocket ripper” strike, used on a pair of doors when there is an inactive leaf with flush bolts or a vertical rod exit device and an active leaf with a rim exit device. Whenever I see this I think, “Cheap bastard,” because the only reason for this half fast solution is money and the desire not to spend it on doing the job right.

This lovely piece of hardware earned the nickname, “pocket ripper,” but hanging into the opening at a convenient height to catch the front pocket of a pair of trousers, resulting in egregious damage to said pocket and colorful language on the part of the victim.

What is the right way to secure a pair of doors? Vertical rod exit devices are the best. My second choice would be a mortise exit device with an open back strike and a vertical rod exit device on the inactive leaf. My third choice would be a mortise exit device with flush bolts on the inactive leaf.

Below are a couple of examples of the ‘pocket ripper.’   On the left is the classic Von Duprin 1609 strike and on the right an example from Ingersoll Rand in Europe.  The European version looks like it has better manners.

In the center we have the Hager 4921 strike that really looks like it could take out more than just a pocket if you catch it the wrong way.

image001image002hager

 

 

 

In addition, I find that often the rim latch stops dead before latching on the strike.  Also, depending on how you install the rim device, the latch may drag across the edge of the other leaf, scraping an ugly divot over time.  Yes, all in all a hardware choice to be avoided if you can.

 

Securitech Lexi Electrified Exit Device Trim

Great Problem Solver

The Securitech Lexi series retrofit exit device trim is available with a variety of back plates and adapters that allow it to be used with most major brands, including many surface vertical rod and concealed vertical rod exit devices.  Compatibility with a variety of vertical rod devices is a major plus.

I mean, anybody can electrify a rim exit device by simply installing an electric strike.  However, while it is possible to install an electric strike on a vertical rod device it rarely brings a good result.  First of all, in order to use an electric strike you have to first lose the bottom rod.  That just leaves one latch at the top of the door to provide all the security.  If it is a tall door or a flexible door – like an aluminum storefront door – you can pull the bottom open several inches with just that top latch holding it.  Add a little time and a little hinge sag and pretty soon you have no security at all.

The other solution is electric latch retraction, or electric latch pullback, as some manufacturers call it:  relatively expensive compared with a Lexi trim.  Also, electric latch retraction is a fail secure only solution when locking trim is used and therefore may be inapplicable to fail safe installs such as stairwells, unless passage function (always unlocked) trims are used.

I notice that right out of the box the Lexi is very self contained.  Other than a tiny box containing mounting screws, tailpiece operators, and a cylinder collar and cam, what you see is pretty much what you get.  It’s pretty hefty for its size – it is designed on the slim side so as to be usable on narrow stile as well as hollow metal or wood doors.   This does mean that the installer may have to be a little creative when replacing a larger exit device trim with the Lexi.

Installation instructions are easy to follow and short – only four pages, including the template. Something I would have liked to see in the instructions, but didn’t, was current draw.  If I am installing one of these, the number of amps it draws are not going to matter much to me.  But if I am installing twenty of them and want a centralized power source, now it’s an issue.  Yet it isn’t anything that an experienced low voltage specialist with a ammeter can’t find out in two seconds.

One of the great innovations I noticed right away is the rotation restriction clip that allows the installer to customize tailpiece rotation to the exit device.  I do not think that this is handled better by any other manufacturer.  Correct degree of rotation often determines whether a trim will work or not, and to have a trim that has degree of rotation so easily selectable is damn nice.

As mentioned in the sales literature, since Securitech’s Lexi trim is compatible with so many exit devices, if you have a facility with different brands of exit devices dispersed throughout, you can install access control and unify the exterior appearance at the same time.  And in addition to being versatile it is also durable.  Forcing the lever only causes its internal clutch to break away, and it can easily be set right by rotating it back the other way.

All in all the Securitech Lexi trim seems to be a well built, versatile problem solver.  I think you’ll find it useful in many access control installations.

Multi-function Doorways, Part Two

Secured stairwell doors are among the most basic multi-function door applications.  In most jurisdictions they must (usually)* be both unlocked and positively latched in the event of a fire.  Unlocked so that if a person, fleeing into the stairwell during a fire, finds the stairwell full of smoke, they can safely exit the stairwell.  Positively latched so that the door will remain latched closed against the spread of the fire.

Until there is a need for access control, a passage function mortise lock, cylindrical lock with UL listed latch or exit device with passage function trim are fine.  The application begins to get interesting when the need arises to lock a stairwell door.

Right up front, electric strikes are out of the question because of the unlocked/positive latching requirement mentioned above.   It is not possible to positively latch a door when the electric strike is unlocked.  There is no such thing as a fire rated, fail safe electric strike.  If you configure a fire rated electric strike to be fail safe it voids the fire rating.

Since electric strikes are unusable for this application, that leaves either electric locks or electromagnetic locks.  Both have advantages and disadvantages.  Fail safe electric locks positively latch whereas mag locks allow the installer to us the existing hardware on the door to accomplish positive latching.  Electric locks require running wire through the door and some means of getting the wire from the frame into the door, such as an electric through-wire hinge.  Not all inspectors like electromagnetic locks, so before you install them be sure to check with your local Authority Having Jurisdiction (AHJ ) – that is, Fire Marshal or Building Inspector.

If the stairwell door already has a fire rated exit device installed, there is probably a fail safe electrified trim available for it.  Once again, this means an electric through-wire hinge or other power transfer device would be required.  Sometimes existing exit devices are incompatible with the electrified trims available for that brand and model of device.  If that is the case, the exit device might have to be replaced with one that is compatible with electrified trim.

Alternatively, there are after market request to exit (a.k.a. RX) switches available for most exit devices.  One could be used to release an electromagnetic lock on the stairwell door.

Usually it is required that all electric locking devices on stairwell doors be controlled by the fire alarm panel.  When the fire alarm is in a state of alarm, it unlocks all the stairwell doors.  Two conductor wire is run from the fire alarm panel contacts to a special fire alarm relay in the power supply that powers the electric locks on the stairwell doors.  The alarm panel opens the circuit, causing the state of the fire alarm relay to change, thus powering down the fail safe locks and thereby leaving them unlocked.

An important detail:  technically speaking, according to most building and life safety codes, fire rated doors can only be modified in a fire rated shop.  Therefore if you field cut a raceway for an electric wire through the cross members of the door, for example, you are probably voiding the fire rating.  I have never heard of anyone being called on this, but it is good to keep in mind.  Just like it is good to keep in mind that the AHJ has total authority over what you can or can’t install.  Best make sure you’re on the same page with her or him, otherwise they do have the power to make you remove what you installed and replace both door and frame to repair the damage.

Happy hardware and good luck to you.


*Some jurisdictions specify that not all stairwell doors need be unlocked in the event of a fire, only certain doors.  For example, I have known some places where code was the door had to be unlocked at every fourth floor.  Check with your local AHD to find out what the rules are for your location.


Multi-function Doorways, Part One

As seen in Doors and Hardware Magazine.

Whenever something is invented, humans find more uses for it.  This is certainly true for door automation and electric locking.  It was not long after people realized a door could be unlocked remotely using an electric strike and a door could be opened automatically using a power operator (automatic door opener) that they began using these devices together.   Of course this combination of devices was soon interfaced with intercoms.  Exit devices with electric latch retraction and electromagnetic locks were thrown into the mix, as well as access control, delayed egress and/or security interlock systems.  Any of these systems alone is sufficient to complicate an installation, but when you start to use several on one opening, that’s when things really start to get interesting.

A hospital can be one of the best places to run into a doorway that needs to perform many functions (pun intended).  Hospitals seem to have more varied reasons to keep different people out at different times, or to let them in or out by different means.  In addition to standard life safety and security issues, hospitals also have to anticipate the needs of patients who may be under the influence of medication and/or mental disorders and/or have physical limitations.  Some patients must be kept inside for their own safety while all patients must be able to exit swiftly and safely in the event of a fire.

Let’s use as an example a hospital emergency ward entrance used primarily by ambulance drivers.  The hospital wants only ambulance personnel and the security guard  to be able to activate the power operator, and to control access by use of a remote switch operated by the security guard  for the general public and an access code by hospital employees (other than ambulance personnel).

Since it is a pair of doors, concealed vertical rod exit devices are the most efficient, safe and secure way to lock them and provide reliable free egress in the event of an emergency.  However, since there is a power operator involved, these devices must be equipped with electric latch retraction; and since use of the power operator was to be limited, a second electric means of opening the door would be required.

A simple way to solve the problem of the second means of unlocking is by using electrified exit device lever trim with one of the concealed vertical rod exit devices.  Persons not requiring the power operator can get in by using the access control, or the security guard  can “buzz” them in using one of two remote buttons.  Because there will be two means of unlocking the door electrically, the security guard  will need a small desk unit with two buttons:  one that activates the power operator and electric latch retraction and one that activates the electric exit device trim.

Below is an amateur wiring diagram (made by me) of how, basically, the system works.

Central to the concept is an access control device with two relays and a request to exit input.  This allows several of the connections to be made through the access control system.  If the access control system on site does not provide more than one relay, the same functions can be accomplished by using additional relays in the power supply.

The system as shown in my illustration above works like this:

Ambulance personnel activate the power operator using the access control system.  The access control system signals the power operator via contact closure in Relay #1.  The power operator triggers the relay in the power supply to retract the latches of the exit devices, then opens the door.

Other authorized hospital personnel use the access control system to unlock the lever trim.  The access control system changes the state of Relay #2, triggering the relay in the power supply to unlock the trim.  They turn the lever, pull the door open and walk in.

Injured people arrive on foot at the Emergency Room entrance.  The Security Guard sees them (or is notified by intercom, not shown) and lets them in by pressing the red button, activating the power operator, or by pressing the green button that unlocks the exit device trim.

There exist many possible variations of this system.  Knowledge of access control systems and door hardware are required, but the most important principal in play is the use of contact closure to signal multiple devices.


Exit Device Checklist

See also Exit Device Basics

Here are a few questions you need to be able to answer before you order exit devices:

  • Is the door made of wood, hollow steel, Fiberglas, aluminum and glass, or all glass?
  • Is the door is fire rated or non-fire rated?
  • Door width if single door or pair of doors with center mullion?
  • Door width and height if for a pair of doors without mullion?
  • Door thickness?
  • Exit device finish?
  • Will this be an exit-only device, or will there be outside trim?
  • If there is outside trim, what function is it?

It will save you time and aggravation if you know the answers to these questions before you call your hardware vendor.

You may also want one or more of these or other mechanical options:

  • Cylinder dogging (not available on fire rated devices)
  • Less bottom rod (for vertical rod exit devices)
  • Double cylinder (trim locked or unlocked from inside secured space)

There may also be electrified options:

  • Does the exit device need to have electrified trim?  If so, fail safe or fail secure?
  • Does the exit device need to have electric latch retraction?
  • Does the exit device need to have push pad or latch monitor switches?
  • Do you need a delayed egress exit device?

Save time and money by gathering the necessary facts before shopping for exit devices.


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