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The Time-Out Room

DormaKaba Stanley Best SSRL seclusion room lock.

The “Time-out Room,” also called a “Seclusion Room,” is, perhaps, a sign of our times. The purpose of a time-out room in a middle school or elementary school is to temporarily segregate an out-of-control student from the rest of the school population.  As you can imagine, the use of a seclusion room is heavily regulated, and regulations vary from state to state, city to city, and even institution to institution.  However, there are some common rules.  For example, such rooms are required to be equipped with a means to see and communicate with the student while they inside the room; the room must be free of objects and conditions that might be potentially dangerous; and the door must be unlocked from the inside.  The room must also be large enough for the student to lie down in without touching a wall, and must have a high enough ceiling that the student will not have to bend.

The purpose of the room is to let the student cool off and calm down before rejoining the school population.  It is not a holding cell.  Its purpose is less as a punishment than a behavioral tool.

What stops the student from leaving the seclusion room?  A person keeps them in.  A person must be present to observe and make sure the student is safe.  I venture to say that same person is the one who gets the student into the room in first place and keeps them there.  With no great stretch of the imagination, one might foresee instances in which the student to be secluded might be significantly bigger and stronger than the person responsible for keeping him and others safe.  It might be physically impossible for the responsible person to keep the student in the room.  They might need help.

The answer could be to put someone large, strong and well-versed in non-lethal martial arts with the patience of a saint in charge of the seclusion room duties, or it could be to use some kind of locking device to keep them in.  But, wait!  You can’t lock them in.  It’s against the rules.  How do you solve the problem?

Often the answer is an electromagnetic lock controlled by a normally open, momentary contact switch.  The magnet is only activated when the button is pressed.  As soon as the responsible person takes their hand off the button the mag lock is unlocked.  Often, local or institutional rules governing seclusion rooms require a time limit on seclusion.  One could add a timer to the system that would automatically release the electromagnetic lock after the permissible amount of time has expired.  Life safety code would demand that the magnetic lock be disabled by the fire alarm.

Pictured above is the Stanley Best SSRL seclusion room lock as seen under the Behavioral Health Products section at the bestaccess.com web site.  One must stand there and hold the lever in position to temporarily secure the door.  In photo we can see that the door is a hollow metal door in a hollow metal frame, and the door has a lite kit in it with wire glass.  I’ll bet it’s a heavy gauge, reinforced steel door, too, judging from the three-point locking version of the SSRL shown.  Clearly they expect trouble.  Through the window they can observe the student and make sure that they are safe.

Since we can see the knuckles of the hinges we know the door swings out.  This eliminates the need for a ligature-resistant handle on the inside of the door.   We’ll talk more about ligature-resistant hardware soon.





Sometimes you just need a little time.

 

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Exit Device Retrofitting Adventures

Monarch model 18

As door hardware evolves, new products emerge to replace older products. This may happen because of a design improvement, or because a company changes ownership, but in either case it means that there are older products in the field for which there are no exact replacements. Any door hardware product may become obsolete over time. Today we are talking about exit devices.

Falcon Model 25

In the mid-Twentieth Century mass production of doors was standardized so that the mortise pocket within a door that houses the mortise lock would always be the same size. Before this standardization mortise locks were available in a wide variety of sizes, but from this time forward all architectural grade lock fronts would be eight inches tall by one-and-a-quarter inches wide. Of course this affected mortise exit devices. So when I went to replace a Von Duprin 8875 mortise exit device manufactured sometime between 1897 and 1920, I found that the mortise pocket was only about six inches tall and I had a bit of cutting to do to make the new device fit.

Companies pay varying attention to the ‘retrofit-ability’ of their products. Some companies make it easy to replace an old device with a new one, and some do not. As an installer it is easy to find oneself marooned out in the field, having identified an exit device by its appearance for the purpose of providing an estimate to replace it, only to find out during installation that it is the old version, and installing the new version is either going to be a lot of extra work, or extra hardware that was not on the estimate.

For example, in the late 1990’s Von Duprin redesigned their narrow stile 33 and 35 series exit devices. The rails remained the same, but the heads were completely changed. The old version did not accept a rim cylinder tail piece, and the new one does. This means the old outside trim will by no means work with the new device – a potentially expensive problem if not anticipated.

Similarly the Precision 2000 series Apex devices are not backwards compatible with the old 1000 series trims.

Monarch was bought by Ingersoll Rand and rebranded under the Falcon line of products, now part of Allegion. During these transitions the trims changed part numbers two or maybe three times. Check with your favorite hardware genius as to whether the trim you have will work with the device you need.

The lesson here is not to judge by appearances. The new Von Duprin 33 looks a lot like the old one and the Precision 2000 looks just like the 1000 series. To avoid expensive mistakes, pull the device off the door and positively identify it before you write your estimate.

Both Doromatic and Jackson responded to the need to replace crossbar devices with touch bar devices by creating touch bar versions that fit the same footprint as their crossbar predecessors. The Doromatic 1690 and 1790 devices replace the 1990 and 2090, and the Jackson 2085 and 2095 replace the 1085 and 1095 devices with very little trouble. A big bonus is that a in the case of the 2085 Jackson and the 1690 Doromatic concealed vertical rod devices, you can reuse the exiting concealed vertical rods.





Knowing what you have is the key to knowing what you want.

 

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Field Reversing the Precision E2203 SVR Exit Device

The Precision E2203 is a Surface Vertical Rod exit device with a solenoid in the head that controls the outside lever trim.  Ordered complete with trim: part number is E2203 × 4908A, specify door width, finish, handing, fail safe or fail secure.  The right thing to do is to order it fail safe or fail secure and handed at the factory for your application. 

But… let’s say for the sake of this article that you ordered the device and did not specify handing or fail safe / fail secure. You might find yourself needing to field reverse the handing.  Here is what you need to know.

Handing

Changing the hand on the basic 2200 device is not very difficult, but changing the hand on the E2200 is fairly difficult, and requires skill, patience and … tape.
For the non-electric, purely mechanical version of this device, changing the hand is not as simple as it is with some other exit devices, for example, flipping the device over, but it is not all that hard to do.  Below are the directions for field handing excerpted from the 2200 Series installation instructions from the Stanley Precision web site.   Why they have arranged the steps to be followed in counterclockwise order is a mystery to me, but I am not here to judge, just inform.

At a glance you can see that there is some disassembly of the exit device head required to change the handing of the device. But when you add electrified trim control it complicates things a bit.

In the photo below you see the wires for the solenoid where they pass through the hole in the bracket.  That bracket is an integral part of the active head and it does not move.  However, the solenoid must be installed at the other end of the active head in order to interface with the working parts of the device and the wires are just long enough to allow it to be installed where it is.  There is no play in the wire that would allow the wire to remain where it is and yet allow one to move the solenoid.

 

 

 

In order to move the solenoid to the other side of the active head, one must either cut the wires (a nightmare, do not do it) or to completely disassemble the exit device, bar and all.

Why do you have to completely disassemble the exit device to pull the wire through?  Because it is taped to the baseplate of with a piece of filament tape that runs the length of the bar.  The tape must be removed to free the wire so you can pull it out through the hole in the bracket.

I could not find the directions for changing the hand of the E2203, but here is a drawing of the solenoid placement for the E2103 rim exit device taken from the installation instructions from the E2103 Kit.

 

 

Once you have pulled the wire through the hole, changed the hand of the head, taped the wire back down the length of the bar baseplate and reassembled the device, you’re done.

Below is a picture of the E2203 with handing freshly changed and the device reassembled and ready to install.

 





Like I said: order it fail safe or fail secure… AND ORDER IT HANDED.

 

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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.  🙂

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.

Securitech Trident Multi-Point Deadbolt Exit Lock

Trident 4-point deadlocking exit device.

Simple and robust design helps to ensure security and longevity; single motion egress ensures life safety code compliance.  

Simple to order and to install, the Trident offers excellent security while preserving life safety.

The first thing I noticed when I unpacked the box was the small number of parts.  The second thing I noticed was how well all of these parts are labelled.  As I read the installation instructions I was struck by how easy Securitech had made the installation process, especially with the inclusion of a metal template to help get everything lined up just right.

I assume that the Trident is named for the three active bolts that secure the door on the lock side, but with the inclusion of the passive hinge side bolt it is actually a four point lock.  The hinge side bolt slides passively into its keeper whenever the door is closed.

Trident is a heavy device, so before installing it, make sure your door swings and closes properly and the hinges are in good shape.  I suggest using hinges with non-removeable pins so as not to rely solely upon the Trident’s hinge side bolt.  A stainless steel continuous hinge would be even better for both security and durability, if it is possible to use one.

Every locking mechanism of the Trident is through-bolted through pry-resistant steel plates, so casual attack using a pry bar would likely be fruitless no matter how much time the would-be burglar might have.  Each locking bolt is substantial and housed in a very sturdy mechanism.  Bending one of them would be difficult; bending all of them enough to gain entry would be almost impossible.  The main outside plate is impressive-looking with its Securitech logo and satin stainless steel finish, and since it is through-bolted to the head of the device in several

Photo by Tom Rubenoff

places, it’s pretty strong, too.

The weakest part of any muli-point locking device is the door frame.  Fully grouted (concrete filled) hollow metal frames hold up the best under attack.  At the very least, to have real security measures must be taken to ensure that the door frame cannot be either pulled out of the wall or bent away from the locking bolts.

To maximize security, I suggest not using the optional exterior key control with this device.  The presence of a key cylinder outside provides a target for burglars.

The Trident comes standard with a paddle that tells the user to push to exit and alarm will sound, but since the alarm is optional, this may be an empty threat.  Be sure to order your Trident with an alarm if you want one.

I was impressed with the workmanship evident in how the Trident is put together.  Everything worked super-smoothly and fit together perfectly.  The strong, simple design looks like it will provide many years of flawless service.  I highly recommend it for the back doors of stores, warehouses or factories or anywhere where a higher level of security may be needed.

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.



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