Editor’s Note: This article is adapted from the new book, “Safe Firefighting: Levels I and II,” by Steve Kidd, John Czajkowski and Garry Briese. It is reprinted here with permission, courtesy of McGraw-Hill Companies. For more information, visit www.mhhe.com/safefirefighting.

Because the building codes and security requirements for commercial buildings differ from those for residential buildings, the steps we take to force entry into commercial buildings also differ. In general, the locks found in a typical commercial door are heavier and stronger. Similarly, the glazing in the doors and windows is thicker, stronger and set in stronger frames with more secure locks than we will expect to encounter in residential applications.

Many businesses use additional security measures after normal operating hours, including iron grates, steel overhead rolling doors and thick steel bars, to secure their businesses against thieves. All of these impede our access and egress from a burning structure and should be considered early in any operation.

Through-the-Lock Entry

Most commercial entry doors have a very strong lock, called a mortise lock, set in a strong frame. Mortise locks fit into a large cavity formed in the door when it is manufactured. The locking mechanism in a commercial mortise lock may be a deadbolt, in which the locking bolt travels horizontally into the doorjamb, similar to a tubular deadbolt. Alternately, it may feature a pendant-style lock that swings vertically into the opening. A mortise-style lock may also have the latch and the locking bolt in the same mechanism, both operating from a single key.

The through-the-lock method for forcing this type of door involves extracting the key cylinder from the door and manipulating the internal mechanism to unlock the door. Glass entry doors commonly used in commercial applications have a thick tempered glass glazing and usually have a heavy metal push bar across the center. It is much safer to force the door open so that it swings freely on its hinges, rather than simply smashing the glass and ducking underneath the push bar. An added advantage to forcing the door to swing: it remains intact, allowing the doorway to be secured after the incident, if necessary.

Tools of Choice

The tools of choice for extracting the key cylinder are the K-Tool, a lock puller or even a good pair of pliers or a pipe wrench (Figure 1). The K-Tool and other types of lock pullers work by driving the extracting part of the tool over the key cylinder and applying pressure to extract the cylinder. Pliers and pipe wrenches work by locking down on the cylinder and turning it counterclockwise. In most cases, the only damage done is to the soft brass lock cylinder, which is relatively inexpensive and can be quickly replaced.

Key tools are used to manipulate the locking mechanism (Figure 2). These tools come in different shapes, each designed for a specific type of lock. The flat key tool has a curved, pointed end and is useful for manipulating most mortise locks, while the pointed straight end works well with several types of tubular or rim locks. The square tool works for tubular- and rim-style locks with a square opening for the key cylinder or doorknob.

Fortified Doors

Because the rear doors to most mercantile and many other types of commercial occupancies are out of plain view, these doors are often the most fortified against crime. Most life safety codes require that these doors remain operable as emergency exits during normal operating hours. However, businesses sometimes use added measures to secure them after hours, and we can’t assume these measures have been removed when the occupant is open for business.

One device commonly used to fortify these doors is the drop bar, which may be made of wood or steel (Figure 3). It rests in saddles attached to the door to hold the drop bar across the entire door opening. The drop bar prevents the door from swinging open, even when unlocked by normal means. Some indicators that a drop bar is in place are the rounded heads of bolt showing on the outside of the door. However, because many of these saddles are welded to the interior surface of the door, there may be no outward signs that a drop bar is in place.

If you suspect that a drop bar is in place, it is often possible to cut an access hole in the door using a circular saw. This allows you to reach in and remove the bar. Still, as an added measure, it is common to find the drop bar secured in place with padlocks on either side to prevent this type of entry. If a quick entry is desired, then cutting the door from top to bottom, directly through the center of the door and the drop bar, may be your best choice of entry method.

Tip: Expect this type of fortification at the rear anytime you enter a commercial structure from the front side and plan an alternate escape route accordingly. Have at least one pair of large bolt cutters available with the entry team so they can quickly overcome any padlocks that may be securing a rear door.

Conclusion

You have probably noticed that there are several methods to choose from when creating access to a structure. Not every method will work every time or for every firefighter. Access problems may prevent you from positioning in a way that allows you to use one method, so an alternative may be necessary. Personnel size and strength may prevent you from using brute force to overcome a tough door. However, the leverage provided by a tool, when applied with a technique that you master through practice, will help you overcome the situation.

Through-the-Lock Method-Extracting the Key Cylinder

Working as a two-person team, use the following method for through-the-lock entry (see photo “Through-the-Lock Method”):

1. Inspect the door to be sure it is locked and feel for heat.
2. Radio to the Incident Commander the location of the door you are going to force and receive confirmation that it should be forced.
3. Place the lock-pulling tool over the cylinder until it “bites.” Drive the tool over the cylinder and extract it from the lock, exposing the mechanism.

Variation: Use pliers or a pipe wrench to remove the cylinder.

Manipulating a Locking Mechanism

Use the following method for through-the-lock entry, starting with the key cylinder already extracted (see photo “Manipulating a Locking Mechanism”) :

1. Look into the opening and determine the location of the locking mechanism.
2. For a mortise-type lock, insert the angled end of the key tool and depress the roller cam or other type of spring-type latch that allows the lock to move. Move the locking mechanism to either the “5 o’clock” or the “7 o’clock” position to open.
3. For a rim or tubular lock, insert the appropriate type of key tool and twist the mechanism to operate the lock.

Tip: It is quite common for a lock to bind in the doorjamb, especially if the fire has heated it. If you shake the door in and out as you manipulate the lock, it will usually open.