Two decades ago, the disastrous fire at the MGM Grand Hotel and Casino in Las Vegas focused the world’s attention on the need for improved fire safety in casinos and hotels. The fire occurred on Nov. 21, 1980, and is one of the worst hotel fires on record in the United States—in all, some 87 people died and 679 were injured.
After the fire, building and life safety code committees reviewed the investigation reports and developed new requirements to address the issues revealed in the documentation. Concern about the fire alarm system should have evoked major interest. Interviews with survivors of the fire indicated they did not receive any indication of the fire from the fire alarm system, but only from other guests or through actually smelling smoke. The investigation disclosed that the fire destroyed the fire alarm system before it could actuate the notification appliances.
One positive result came from the fire. The codes (National Fire Protection Association [NFPA] and International Building Codes) now require all casinos and hotels to have automatic fire sprinkler protection. The codes also require such facilities to have a fire alarm/voice communication system installed as well. Another positive outcome is that most casinos now have dedicated fire protection staff with radio communications to the casino’s Fire Control Center.
What issues might a contractor experience when performing a fire alarm system installation in a casino? Typically, an aggressive schedule will move the project toward completion. A successful installation will rely heavily on careful planning and efforts to ensure on-time arrival of the equipment. Given the new programmable technology used today, an aggressive construction schedule, coupled with inattention to operational requirements and device labeling, could lead to extended opening delays. What’s needed and where The fire alarm system design must address the mixed occupancy characteristics of a hotel and casino. High ambient noise levels and the flashing lights operating throughout the casino floor present additional design challenges. The needs of the owner will also control the development of the system’s operational characteristics. Items such as selective notification and system expansion capabilities might appear higher on the owner’s list of preferred operational characteristics than they would on the authority having jurisdiction’s (AHJ) list.
The basic fire alarm system design must comply with the most stringent parts of mixed occupancy requirements of the NFPA 72, National Fire Alarm Code; and NFPA 101, Life Safety Code; or the International Building Code-2003. In the example of a casino and hotel occupancy, the applicable requirements for assembly and residential (hotel) occupancies for fire alarm systems will apply, as described below.
Normally, the systems providing protection throughout the building—including manual fire alarm boxes, smoke detectors and automatic sprinkler system waterflow—will initiate an alarm signal on the required fire alarm system in the casino (assembly occupancy). In the hotel portion of the mixed occupancy, each of the following devices will normally initiate an alarm signal on the required fire alarm system:
• manual fire alarm boxes in the natural exit access path near each required exit from an area and on each floor
• additional manual fire alarm boxes located so that, on any given floor in any part of the building, no one will need to traverse a horizontal distance on that floor exceeding 200 feet to reach a manual fire alarm box
• a manual fire alarm box located at the hotel desk or other convenient central control point under continuous supervision by responsible employees
• a waterflow switch initiated by each automatic sprinkler system and automatic smoke detection serving common areas, corridors and mechanical spaces.
In addition to these devices that initiate an alarm signal on the fire alarm system, the contractor must install an approved single-station smoke alarm in every guest room and living area and sleeping room within a guest suite. In new construction, where two or more smoke alarms are installed in a dwelling unit, suite of rooms or similar area, they must interconnect, so that operation of any smoke alarm will cause the alarm notification appliance to sound in all smoke alarms within the dwelling unit, suite of rooms or similar area.
Occupant notification requirements Both the casino and hotel must have notification appliances to alert the occupants to an emergency. However, where total occupant evacuation would prove impractical due to the building configuration, the fire alarm system needs only to initially notify the occupants in the affected zones. Notification signals for occupants to evacuate must use both audible and visible signals in accordance with NFPA 72, National Fire Alarm Code-2002 and ICC/ANSI A117.1, American National Standard for Accessible and Usable Buildings and Facilities, or the system must provide other means of notification acceptable to the AHJ.
During an emergency, the system must make announcements via an approved voice communication system or a public address system provided with an emergency power source. This voice notification must remain audible above the casino’s ambient noise level. In areas that can be occupied other than guest rooms and suites, the system must provide visible notification appliances. And, guest rooms and suites specifically required and equipped to accommodate hearing-impaired individuals must have a visible notification appliance.
The emergency evacuation plan for the facility may use the system to selectively notify occupants in other zones to allow for orderly evacuation of the entire building. The required fire alarm system may also use positive alarm sequences that will delay the evacuation signal to the occupants while sounding an audible alarm at a constantly attended receiving station within the building. The system may notify occupants by means of visible signals and voice announcements, either live or recorded, initiated by the person in the attended location.
Because the MGM Grand life safety system was disabled early in the fire, the system design must address the survivability of the circuits connected to the speakers of any voice communication system serving a casino and hotel.
The requirements offer options as to how a designer and contractor may improve survivability. NFPA 72-2002 requires the design and installation of survivable fire alarm systems provide assurance that attack by fire within an evacuation-signaling zone will not impair control and operation of the notification appliances outside the zone. The design must provide for the protection of all circuits necessary for notification-appliance operation until they enter the evacuation signaling zone they serve. The code accepts any of the following methods as a means of meeting the requirements:
• a two-hour rated cable or cable system [circuit integrity (CI) cable or MI cable]
• a two-hour rated enclosure
• performance alternatives approved by the AHJ.
Fire alarm system design documentation must include a description of the performance features provided to ensure survivability. The documentation must also provide for a technical justification, submitted to the AHJ, to allow the fire official to determine if the design has met the survivability requirements. Some of these features may include the use of fire-resistant cable or cable systems in areas not protected by automatic sprinklers or two-hour-rated enclosures.
Fire department notification requirements
Although the code permits positive alarm sequence (delayed notification to the occupants), the design must provide for the immediate notification of the public fire department in the event of fire. The fire alarm system may transmit the alarm automatically via any of the following means acceptable to the AHJ and in accordance with NFPA 72:
(1) auxiliary alarm system
(2) central station connection
(3) proprietary system
(4) remote station connection.
One of the code changes resulting directly from the MGM Grand relates to unlocking doors in stairwells. A majority of those who perished in the fire died in stairwells that had filled with smoke. The investigation disclosed that the occupants who had entered the stairwells could not reenter the floors due to stairwell doors that locked behind them. The doors were locked to provide security to guests from unauthorized people accessing the guest floors from the stairwells. Today, a fire alarm and control system must automatically actuate the control functions necessary to make the protected premises safer for building occupants. In addition to control functions such as the standard release of door hold-open devices, fan shut down, control of smoke management systems and emergency lighting control, the fire alarm system must also unlock all doors when the system initiates into an alarm condition. The installation of these emergency control devices must meet the requirements of NFPA 72. They also cannot impair the effective response of all required alarm notification functions.
Given the high occupancy rates of most casinos, correct and accurate information regarding fire alarm device actuation locations must transmit to the fire command center. At the command center, the system must provide both audible and visible indicators for annunciation. And the system may provide annunciation by point identification or by zones (floor, wing, etc.). Where an automatic sprinkler system protects the building, the code permits the area of the fire alarm zone to coincide with the allowable area of coverage of the sprinkler system.
Tackling a fire alarm system installation for a casino/hotel operation takes a thorough knowledge of codes and a carefully designed specification for all areas of the facility. Obviously, the professional contractor needs to assign specifically trained installation teams who have knowledge about complicated fire alarms to install these systems. A contractor just getting started or with little knowledge and background should avoid taking on the responsibility of designing a system of this magnitude. Only a licensed professional fire protection engineer should undertake the creation of a system designed to promote life safety for the occupants.