Tailoring access control to fire codes
May 1, 2001 12:00 PM
By MICHAEL FICKES
The basic problem boiled down to a dispute over the definition of a primary power supply.
Security system integrators welcome the opportunity to install access control and CCTV systems in new structures. It eliminates a host of problems, especially when it comes to cabling. Designers can specify a conduit that provides plenty of room for all cabling, including what is needed by access control devices, cameras, and their power supplies. New plans can also attend to security system monitoring requirements with spacious and ergonomic designs for the security station and security center.
Security systems simply fit more easily and better into facilities designed with security systems in mind. New construction does, however, pose unique challenges for security system integrators.
When CIS Security Systems Corp., Springfield, Va., designed the security system for a new Raytheon Technical Services Co. building in Reston, Va., a suburb of Washington, D.C., provisions in the local fire code required several innovative tweaks in the access control system.
"We met with county building officials on several occasions to develop ways of working around these problems," says Charles Nokes, director of strategic planning for the company. "Still, it took about two months longer than expected to get the final fire code approval. That cost money. Since we were already occupying the building and couldn't lock it down, we had to pay guards 24 hours a day while we solved the problems."
Under the CIS plan, Lenel Systems International, Pittsford, N.Y., provided an OnGuard Windows NT access control system, while HID Corp., Irvine, Calif., provided combination proximity card and keypad readers for approximately 25 doors throughout the facility.
Backing up the access control system is a 15-camera CCTV system provided by Pelco, Clovis, Calif. All of the cameras provide high-resolution color video, with two external cameras reverting to black-and-white at night. Ten of the cameras monitor from fixed positions, while five pan/tilt/zoom Pelco Spectra domes scan sensitive areas. Controlling the camera system is a Pelco 9740 matrix switcher, integrated with the Lenel access control system to drive preset camera positions and to call up cameras from programmed alarms. Sony Security Systems, Park Ridge, N.J., supplied an HSR-1 digital surveillance recorder for the system.
The fire code, however, required CIS to fine-tune its design in two areas:
That the fire code conflicted with the security system design surprised everyone. "We submitted drawings of the system to Fairfax County, the Virginia jurisdiction where the building is," says Greg Altieri, vice president and general manager of CIS. "And the county approved those plans.
"But when the fire marshal inspected the finished system, he refused to approve the installation because of a code that forbids battery back-ups on magnetic locks."
The second problem arose in the underground parking level of the five-story, 223,000 square foot building. Right next to the drive-in ramp, a stairway leads to a door that exits to the sidewalk outside. Inside the garage, about 50 feet back from the ramp and front-stairwell exit, a controlled elevator and a door opening onto an interior stairwell provide access to the building. "We put a magnetic lock and card-reader on the door to the interior stairwell," Altieri says. "This prevented unauthorized people from entering the building from inside of the garage."
It became an issue during discussions with county officials about the battery back-up system. Officials reviewing the security design believed that the unlocked door at the front of the garage allowing people to move to the outside of the building would prove insufficient for people who might be trapped in the rear of the garage. The fire code called for two exits. In the marshal's judgment, the front door to the garage was too close to the ramp to count as the second exit.
Working out both of these fire code issues fell to Altieri during the installation of the Raytheon security system.
EMERGENCY POWER VS. MAGNETIC LOCKS
Despite the county's approval of the original plans that backed up the magnetic door locks with batteries prior to the installation, the fire code did indeed prohibit the use of batteries for backup power.
Searching for a solution, Altieri studied the fire code literature. At first glance, the code language seemed clear enough: "All exits¡shall unlock upon loss of primary power to the fire alarm system serving the protected premises. The secondary power supply shall not be utilized to maintain these doors in the locked condition."
An appendix to the code offered an explanation for the provision. While battery backup power, considered a secondary power supply, may supply enough power to keep the locks energized, such a backup might not provide enough power for the fire-alarm system.
The Raytheon facility also contained a backup power generator. Altieri suggested tapping that power source to maintain the magnetic locks and the fire alarm system.
No, responded the fire marshal. As a secondary power supply, a back-up generator could not qualify as a reliable source of power in the event of a power outage.
The basic problem boiled down to a dispute over the definition of a primary power supply. The fire marshal contended that a backup generator constituted backup power.
But the code appendix expressed a different view and even offered the example of a hospital using a back-up generator to maintain power during an outage in a configuration identical to that being proposed by Altieri for the Raytheon building.
According to the appendix, an emergency generator capable of operating the fire alarm system eliminated the concern about insufficient secondary power.
The fire marshal reviewed the appendix and agreed to the proposed solution. The magnetic locks are supplied by Security Door Controls (SDC), Westlake Village, Calif.
TRANSFORMING A SECURE DOOR INTO A CONTROLLED FIRE EXIT
Dealing with the need for an additional fire exit leading from the garage into the building required technical modifications to the door located toward the rear of the underground parking garage.
Neither Altieri nor Nokes relished the idea of allowing uncontrolled access through that door. But how could an unattended door provide both security and emergency access?
"We put a magnetic lock and card reader on that door because we didn't want unauthorized people entering the building by walking down the parking ramp and using that door," Altieri says.
Ultimately, the connection to the Lenel access control system made it possible to adapt the door and satisfy the fire marshal's concern.
Like most electromagnetic door locking systems, a metal armature plate at the top of the door abuts a large electromagnet attached to the door's frame. When an individual presents an authorized card to the reader, the system cuts electricity to the magnet, allowing the door to open.
To modify the way the door functions, Altieri inserted a pressure sensitive circuit breaker into the wiring that goes from the door to the Lenel control panel. The result is what Altieri calls a delayed egress door. An individual inside the garage faced with a fire emergency need only push on the door for 15 seconds.
"We allowed about an inch of play in the armature plate assembly," Altieri says. "When you push on the door for 15 seconds, the lock will release and you can open the door."
Securitron, Sparks, Nev., supplied the lock with armature plates and delayed egress circuitry; CIS installed it and aligned the input and output devices to do the job.
The outside or garage side of the door carries a sign with instructions: "Push until alarm sounds. Door can be opened in 15 seconds."
When the lock opens, an alarm sounds in the garage and in the security center. If someone is simply leaning against the door, the alarm will back the person off. Meanwhile, the Lenel system will signal officers in the security center that the garage door has unlocked. A CCTV camera located in the garage will switch on the alarm screen, letting the officers know if the emergency is real or not.
To reset the alarm, officers must go to the door and key a special box attached to the inside of the door's frame. This ensures that the door cannot be relocked in an emergency.
Inside the door, on the stairwell side leading up to the lobby, a motion sensor and an emergency exit button allow people inside the building to exit to the garage.
In the end, the technical installation of a security system may look easier in a new building, but important issues of code compliance can add complications already worked out in an existing structure.