Exit Device Basics

Exit devices are designed to be installed onto the secure side of outswinging doors. They restrict access while providing free egress. The exit device developed in the United States was introduced after the loss of lives in a number of building fires, including the infamous Iroquois Theatre Fire of 1903, where more than 600 people died. The exit device solved the problem of people being crushed against the doors because they first did not have prior knowledge of how to open the door or time to unlock and open the door.

Early exit devices used a metal tube (cross bar) between two cases that were attached onto each side of the door. The active case has a latch bolt that would retract when the tube was pushed in a downward and forward direction, permitting the door to swing open. This way, if someone “crashed” into the exit device, the latch would release and the door would swing open.

A number of manufacturers continue to offer the traditional cross bar. Precision Hardware’s Olympian Series crossbar style exit devices chassis is constructed of investment cast steel. Exit devices have evolved to incorporate rail style device using forward mounted pushpad. Any horizontal force on the pad will release the door.

There are three common types of exit devices: rim, mortise lock and vertical rod. Most common is the rim exit device that was probably named “rim” device as their latching mechanism is very similar to the rim locks sold in the East and Midwest during the early 20th century. Both the rim lock and the rim exit device are surface mounted on the secured side of the door. The rim exit device is a self-contained door lock mechanism. The latch bolt is located within the center case or chassis.

Rim exit devices have a surface-mounted latch or bolt that slides over the surface-mounted strike. The more common latch is a Pullman style that swings back at an angle as the bar or pushpad is depressed. The latch is located at the front edge of the center case. A deadlatching mechanism prevents the latch from being forcibly retracted in order to gain unauthorized access. Rim exit devices can be equipped with exterior trim containing a lock cylinder.

The bolt style rim exit device is a relatively new introduction sold through several exit device manufacturers including the Corbin Russwin ED5200S SecureBolt™. When locked, the deadbolt style latch extends onto the strike, limiting the space between the bolt and the strike.

The mortise lock style exit device incorporates a mortise lock normally without deadbolt mounted in the door pocket. The mortise lock is part of the exit device. A standard mortise lock is not designed to operate as an exit device. When the push bar is pressed, the spindle or tail shaft rotates retracting the latch bolt, permitting the door to swing out. Mortise lock exit devices can be equipped with exterior trim containing a lock cylinder. The exit device is mounted onto the interior side of the door with the mortise lock mortised into the door edge.

Although mortise lock exit devices can be installed onto single door openings, the mortise lock exit device is often installed onto the active leaf of a pair of doors. The inactive leaf can have a vertical rod exit device or flush bolts that secure the pair of doors within the opening if there is no mullion.

Vertical rod exit devices are available in the concealed or surface versions. The rods connect the device’s pushpad to the top and bottom latches. Vertical rod exit devices can be configured as top and bottom rod, or top rod only, commonly known as Less Bottom Rod (LBR). LBR exit device installations are normally for interior or doors within a secured area. For specifics on the applications of LBR exit devices, see the IBC 2009 codes.

Von Duprin has introduced the Concealed Vertical Cable Systems for fire rated and non-fire rated openings using the 98/9949 Series and the 33A/35A49 Series exit devices. In place of the rods, a cable is run from the device chassis to the top latch. Then, a second cable is run from the top latch to the bottom latch.

Important: Prior to purchasing and installing exit devices, contact the Local Authority Having Jurisdiction (LAHJ) to ensure the products to be installed meet their criterion.

Most exit devices can be installed onto wood, hollow metal and aluminum doors as long as the stile is compatible with the device. There are exit devices for aluminum glass doors with narrow stiles. The narrow stile pushpad exit device has a narrow center case or chassis. The standard stile exit device chassis is usually more than two inches wide, where the narrow stile exit device chassis is less than two inches wide. For example, the Falcon, Monarch and Dor-O-Matic exit devices are compatible with aluminum stiles as narrow as 1-3/4”.

Depending upon the manufacturer and the model, exit devices are manufactured in a variety of metals. DORMA 9000 Series exit devices are corrosion-resistant, heavy gauge stainless steel.

Exit devices can be installed with or without exterior trim. Trim choices include pull handles, keyed trim, electrified trim and lever trim. Cal-Royal offers cylindrical lock lever trim that enables the exterior trim for their exit devices in order to be compatible with existing door hardware. Remember, the width of the stile affects the dimensions of the exit device and the trim.

For commercial applications, the Ervos X61 series exit device retrofits to a standard 161 (cylindrical lock) cutout. The X61 complies with the requirements of ADA. The Ervos X61 Series single door exit device is available in a variety of architectural finishes and paint colors.

Exit devices are differentiated as being fire rated or non-fire rated (panic). The less expensive panic exit devices are installed onto a non-fire rated doors. Fire rated exit devices are designed for installation onto fire rated doors. Fire rated exit device hardware is manufactured to accommodate the requirements for a fire rated opening. A fire rated exit device will have a fire label prominently located on the device often on the lock edge of the cover. If there is no label, the device cannot be considered fire rated.

Fire rated exit devices cannot be equipped with mechanical dogging as a fire rated opening must be able to have the exit device lock mechanism to latch during a fire. The electrified dogging on a fire rated exit device must be wired through the fire alarm system that would release the dogging mechanism, enabling the latch to latch should there be a fire. Non-fire rated exit devices can be mechanically dogged using an Allen wrench type key. As an alternative, lock cylinder dogging requires a properly cut key to engage or release the dogging mechanism.

The types of panic and fire rated exit devices installed onto a door or pair of doors vary depending upon the application for the opening and the aesthetics of the architect. Lock manufacturers including Sargent Lock, offer a variety of exit devices including; heavy duty, commercial, light commercial and aesthetic styled exit devices.

Exit devices can accommodate single-door and double-door applications. A double-door opening can be configured with or without a mullion. A mullion is metal rectangular tube specifically designed to be mounted to the floor and the doorjamb header. The mullion is located in the center of the opening, providing latching points for each door lock. The mullion enables both doors to be equipped with either a rim or mortise lock exit device instead of at least one vertical rod exit device. There are permanent and removable mullions. The disadvantage of a mullion is it cuts the clear opening in half. A clear opening is the distance between the two opened doors or the door and the mullion, measuring from the two obstructions that extend into the opening. An obstruction can be the exit device rails and pads or the mullion.

To increase the clear opening, companies have integrated the exit device into the face of the door. This reduces the height of the push bar, providing an increased opening. The Adams Rite RITE Door® can be ordered with the exit device is recessed into the face of the door.

International Building Codes/International Fire Codes (IBC/IFC) requires a minimum of three-point latching for double-door openings without a mullion. This can be accomplished using different exit devices. For example, a common double-door application is a vertical rod exit device and a mortise exit device. The mortise lock exit device is the active leaf door and the vertical rod exit device is the inactive leaf exit device.

A mortise lock exit device can be installed with an Open Back strike plate. This configuration permits the inactive leaf of a double door opening to be opened without opening the active leaf as long as there is no astragal installed onto the active leaf.

However, if this type of installation has an astragal, a standard strike plate and door coordinator is required to make sure if both doors are opened, the vertical rod exit device equipped door will close and latch first. Then the mortise lock exit device leaf with the astragal will close and latch into the strike mounted onto the inactive door leaf.

Another option is two vertical rod exit devices that latch using top and bottom rods. They provide four point latching; satisfying codes for fire rated cross corridor doors. Cross corridor doors are pairs of doors that extend across the entire corridor.

For a pair of doors, Von Duprin manufactures three-point latching exit devices that are designed for electric latch retraction. The electrified latching mechanism is wired into a power door operator that when the activation signal is sent, the exit device retracts the top and bottom latch and a deadbolt in the mortised lock, permitting the doors to swing open.

For hospitals, hotels, concert halls, etc., cross corridor doors provide large clear openings for higher traffic applications and wide clear openings in order to transport patients in a bed or gurney. They also can provide a separation area and are installed in hallways at fire walls. Most cross corridor doors are single egress, both swing in the same direction.

Cross corridor doors can be double egress as each door swings in the opposite direction. This configuration is not used on the exterior of a building, but typically in a firewall application. They can be useful for traffic control as each leaf swings in the direction of travel.

Another specialized application for an exit device is to delay egress for specific applications for either 15 or 30 seconds. They can be for infant areas in a hospital, museums or special applications. The Alarm Lock Sirenlock™ 715 has a 15 second delayed egress with instant 95db Dual Piezo alarm. In an actual emergency or fire, the 715 instantly sounds the alarm meeting NFPA 1012 Life Safety Code. Depending upon the codes, delayed egress requirements vary. Research your building codes and realize the LAHJ has the final word.

Alarmed exit devices sound an alarm when the device is operated. For example, the Detex ECL-230X Series Exit Control Locks are code compliant, one, two or three point panic devices with a 100 decibel alarm for secondary exits. These heavy duty exit devices are available with hinge side bolts that engage the door into the frame for additional protection.

The Sargent and Greenleaf Arm•A•Dor™ Panic Exit Device Series is designed to resist basic operational abuse and forced entry while maintaining minimal resistance for egress. The Arm•A•Dor meets life safety codes.

For specialized applications, single motion egress rim devices can be configured to a variety of access control devices including a high security combination lock. Lock One® LKM7000 Series high security rim devices from Lockmasters meet Department of Defense and National Industrial Security Program Operating Manual (NISPOM) specifications. These exit devices can be installed on inswing and outswing single or double hung doors.

Electric latch retraction has been available for a number of years being used on openings equipped with power operators. Until recently, electric latch retraction was powered by a solenoid. Solenoids require a surge of power to operate. Once the operation has been completed, less power is needed to maintain the operation. As a result, solenoid electric latch retraction is usually very noisy, an unwanted distraction. Motor driven electric latch retraction is quickly replacing solenoids as they require less power and are much quieter.

K2 exit devices are tested and certified to exceed 1,000,000 cycles, which is above the requirements for Grade 1 certification. They come with a lifetime mechanical and 3 year finish warranty. The finish warranty excludes 613, oil rubbed bronze finish.

Exit devices have been available for about 100 years, with continuous improvements and increased capabilities.

For more information, contact your local locksmith distributor or:

To read additional Locksmith Ledger articles on exit devices, visit http://tinyurl.com/exit1012.

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