Inmates will abuse any building component within reach. So how do you design a system to detect and protect while keeping it safe, too?

Any building environment prone to vandalism requires special fire and life safety systems design considerations. In the case of prisons and correctional facilities, fire and life safety response planning differs from other high-abuse environments because the majority of the occupants are behind locked doors. This poses unique challenges in terms of fire safety and may be the most difficult to protect from fire, in part because the cardinal rule of immediate evacuation does not apply.

There are many different functional buildings, or sections of buildings, in a prison, including workshops, laundries, stores, classrooms, athletic facilities, religious facilities, administrative offices, medical units and the house-blocks. Special consideration is needed in the cell blocks, and potentially the medical unit, where prisoners are locked into their accommodations.

Similar to public hospitals, prisons and mental institutions adhere to a “protect-in-place” strategy, opting to relocate occupants from the area of fire origin to a secure area within the facility. Yet, to be effective, fire and life safety systems in these sites must incorporate highly intuitive, cutting-edge technology in compliance with local regulations and applicable standards.

Designing for High Security

Fire protection designs for a prison follow strict guidelines that are spelled out in NFPA and local building codes. NFPA 101^®: Life Safety Code^®, requires new jails to be constructed of limited- or non-combustible materials. Automatic fire sprinkler and detection systems are mandated to be present throughout. When dealing with potentially hostile facility types, NFPA 101 also requires a manual, automatic or combination manual/automatic fire-alarm system to be installed.

In addition, the Federal Bureau of Prisons has a set of fire protection guidelines for federally controlled correctional facilities. The guidelines are focused on providing life safety for the inmates while emphasizing the need to minimize fire hazards as well as to remove the opportunity for vandalism in the form of arson. Smoke control often plays a key part of the design and fire engineering approach.

Fire and life safety within controlled-access institutions can be achieved through the use of early warning smoke detection, automatic sprinklers, compartmentalization, established fire zones and a relocation plan. Considering the small space and restricted means of egress, early detection and response are critical.

Prisons have the reputation for being the worst abusers of fire protection systems. Finding a balance between effective smoke detection – while avoiding nuisance alarms – and tamper resistance often leads to installation of detectors behind ventilation grilles, outside cells or in cross-listed cages. This makes maintenance, testing and inspections cumbersome. Early warning is imperative for controlled response and evacuation before reaching dangerous levels of carbon monoxide, carbon dioxide and temperature.

Viability of Spot Detection

Typically, photoelectric and ionization detectors are used to passively detect smoke. These addressable, early warning smoke detectors, as well as heat detectors, can be an option for protecting a prison if they are tamper resistant and are strategically placed to avoid vandalism.

Not only do the devices need to be out of the physical reach of inmates who could damage or disable them; they must also be out of the range of other destructive sources, such as water that inmates could throw on the devices. Therfore, placement and installation can be just as important as the type of detection chosen.

Another viable solution is intelligent Very Early Warning Fire Detection spot detectors, which are similar to traditional detectors except that they employ a more advanced detection method. For example, laser-based smoke detectors are up to 100 times more sensitive to smoke than standard addressable or conventional smoke detectors. They are designed to respond to incipient fire conditions as low as 0.02% obscuration per foot to provide valuable time for personnel to investigate the affected area and to take appropriate action.

[The Federal Bureau of Prisons] guidelines are focused on providing life safety for the inmates while emphasizing the need to minimize fire hazards as well as to remove the opportunity for vandalism in the form of arson.

Because intelligent laser smoke detectors are individually addressable, they are able to send information to the central control station, thereby pinpointing the exact location of the smoke. This can be key to providing the protect-in-place strategy in that officials can immediately identify the problem area and take action, including sending someone to investigate the problem and moving occupants to a different section of the facility.

Aspiration: High Sensitivity and Security

Aspiration detection systems, which are capable of detecting byproducts of combustion in concentrations as low as 0.00046% obscuration per foot, offer advanced and Very Early Warning Fire Detection for specialized applications, as well as for sites requiring more careful consideration.

Because aspiration systems use a series of pipes with pinpoint holes to continuously sample the air for trace amounts of smoke, these detectors are well suited for prisons and other vandal-prone environments. The pipes can be run through the ceilings or other building components, well out of the reach of prying hands. Plus, any portion of the piping projecting through to the protected rooms is so minimal that it can even be difficult to see. Most importantly, aspiration detection provides enough time for personnel to plan or conduct a controlled response, whether it’s to suppress the smoke source or to evacuate a portion of the facility, which is important for protecting lives while maintaining security.

Aspiration detection can be installed in various areas of a facility and can be programmed at different sensitivity ranges. In a prison, range adjustment enables aspiration systems to work just as well in machine shops or boiler rooms within the prison as they do in individual cells or common areas, while allowing for differences in air quality, humidity, temperature and other factors.

Sprinkler Considerations

Fire sprinkler systems are yet another component of the fire and life safety system in prisons. Many designs are adjusted to minimize vandalism to the sprinkler heads. Because the sprinkler heads are an easy target, especially for bored inmates or institutionalized patients, pre-action fire sprinkler systems with pop-out designs are widely used.

An electronic valve controlled by the heat or smoke detection unit in pre-action fire sprinkler systems holds back water. Individual sprinkler heads open to release water onto the areas where it is most needed and concentrate the flow of water directly onto the fire.

Pre-action systems normally have only pressurized air in the pipe; merely releasing the air pressure will not allow water into the pipe. The pre-action valve is controlled by a releasing panel, which can be configured to release water after receiving one or multiple signals.

The fire and life safety system design for prison and correctional facilities takes on elements that challenge current detection technology. The high potential for vandalism and suicide attempts adds equipment considerations that can be easily overlooked by those unfamiliar with this environment. Understanding the features, listings and approvals for the devices is always a primary element of a system design.

Systems for prisons have unique considerations and elements outside of the typical standards and building codes. Care must be taken to ensure all aspects of the design have been properly evaluated to ensure the safest fire and life safety system possible.

OSHA Fire Response Regulations for Prisons

Locked Doors: According to OSHA (Occupational Safety and Health Administration), correctional, mental and penal facilities have slightly different fire response regulations than other types of workplaces and public places. OSHA requires that all buildings have exit routes unblocked by any locked doors or other obstructions to a fast and efficient exit. In the case of mental, penal or correctional facilities, locked doors may block exit routes as long as supervisory personnel are continuously posted along the exit routes, as necessary, to allow a fast exit response in case of emergency. Guard personnel must be trained in emergency evacuation procedures and be prepared to unlock any doors at a moment’s notice. In these cases, according to OSHA regulation 1910.36(d)(3), exit route doors may be locked from the inside, given that the facility has an escape plan in place.

Means of Egress: OSHA requires that all public places and workplaces have a clearly marked, easily navigable means of egress, or exit route, in case of an emergency such as a fire. This means of egress must meet all of the criteria for regular workplaces. Locked, guarded doors are permissible in correctional facilities, however. Otherwise, the facility must have at least two exit routes and as many additional routes as necessary to allow full evacuation in a timely manner. The main exit door of the exit route must remain unlocked and must swing outward, hinging on the side.

Alarms and Detectors: Any fire extinguishers, alarms and detectors all undergo regular inspection and testing to ensure their proper functioning as required by OSHA. The precise number of fire extinguishers, alarms and detectors required in a correctional facility varies by state and even locally, according to which version of the National Fire Protection Association code an area uses as its standard. As part of emergency readiness training, all guard personnel must be trained and capable of using fire extinguishers as needed.

Environments with high airflow or excessive temperatures, such as freezer or cold-storage warehouses, require robust and flexible fire protection solutions. These extreme environments present unique fire detection and suppression challenges that do not follow standard fire and life safety design. For example, while extremely cold, these warehouses can have such dry atmospheres that fire can spread faster than normal. As a result, each scenario needs to be evaluated to provide the necessary protection. Because there is no one-size-fits-all fire and life safety solution, familiarity with all technologies associated with fire detection, notification and suppression are important for designing a dependable and suitable system.

Cold-storage warehouses typically handle a variety of materials, including wooden pallets, boxes of food, fiberboard containers, egg cartons, waxed paper, cloth wrapping, and grease impregnated paper or cloth. Some of these items are highly combustible.

These warehouses also may have freezers that operate at temperatures of –31°F (–35°C) with high airflows; storage areas often operate at a more moderate 39°F to –4°F (4°C to –20°C) with reduced air movement. These low temperatures have an adverse affect on the smoke plume, which is cooled more rapidly than in normal environments. Hence, only fires with great intensity generate sufficient heat to raise the smoke to ceiling level where standard, ceiling-mounted devices would be installed.

Under steady-state conditions, humidity does not pose a problem. Moisture levels can increase, however, due to external air entering the area via normal movements (ingress/egress) and because of routine frost/thaw. Any moisture condenses and quickly freezes on thermal transfer points such as walls and ceilings, including spot-type smoke detectors.

Spot-Type Photoelectric and Ionization Detectors

Ceiling-mounted chiller-fan-coil units or ventilation systems commonly maintain freezers at temperatures well below the operating range of traditional spot-type smoke detectors. As a result, spot-type ion or photoelectric detectors are typically not an option for protecting these spaces. The normal UL listings for these devices would not allow them to be used in environments below 32°F (0°C).

Ion detectors offer limited or slower capabilities in areas with high airflow, which is typical in cold environments. They are not recommended for use with airflows above 300 feet per minute (fpm) (3.8 mph) per NFPA 72.

Traditional and high-sensitivity photoelectric smoke detectors, however, are a potential option in areas maintained above 32°F (0°C) as they can be more responsive in high-airflow environments.

Photoelectric smoke detectors typically use a pulsing infrared light emitting diode (LED) located in a sensing chamber designed to exclude light from any external source. A photodiode is placed at an angle to the LED so it normally does not register the column of light emitted by the LED. When  smoke enters the chamber, the LED  pulse is scattered by the smoke particles and registered by the photodiode. If the photodiode “sees” smoke at a sufficient level, the detector goes into an alarm state. Higher sensitivity can be achieved by replacing the standard infrared LED with a laser light source.

Beam Smoke Detectors

Beam smoke detectors may be necessary in cold storage areas with high, open spaces to cover the peaks that typical spot-type detectors might not be able to effectively protect or when smoke might not reach the ceiling due to stratification. These detectors have a wider operating temperature range than typical spot detectors and work well in colder environments. Beam smoke detectors also include a full line of accessories, such as heater kits that counter the effects of condensation on the reflector and the optics, heavy-duty mounting kits, and long-range kits to help installers meet a variety of application requirements.

A beam smoke detector is made up of three main parts: the transmitter, which projects a beam of infrared light; the receiver, which registers the light and produces an electrical signal; and the interface, which processes the signal and generates alarm or fault signals. When smoke particles obstruct the beam of light and a pre-set threshold has been exceeded, the detector goes into alarm. A reflected beam smoke detector is a single unit that includes the transmitter, the receiver and the control electronics. The transmitter projects a cone-shaped beam of modulated infrared light to a reflector (prism). The reflector returns the beam to the receiver, which measures the amount of light received and converts it to a signal for processing in the control electronics. Reflected beam smoke detectors provide a very wide coverage area – up to 19,800 sq. ft. (330 ft. x 60 ft.) – and include a reflector mounted opposite the transmitter/receiver. Only one device needs to be wired.

Aspirating Smoke

Aspirating smoke detection provides detection in high-airflow environments by actively sampling air from a protected zone via multiple sampling holes in a pipe network. They are also well-suited to hot, cold, or other extreme conditions because the sampling ports can be run into the difficult space while the device can be mounted in a more easily accessible, remote location to protect it from extreme conditions. In addition, one device can typically protect a large area, reducing the time and effort it takes to monitor, maintain and service the fire system. For cold applications, the air may need to be warmed and pass through condensation traps before it reaches the device.

Fire systems for cold environments must often contend with both the extreme temperatures and high air flow to be effective.

An aspiration system uses a fan to actively draw in air through a network of piping. The sample then passes through a filter and into the sensing chamber of the detector. Using advanced sensing technology, the detector analyzes the air sample and sends a signal of airborne smoke intensity to a remote or integrated display module – as well as a fire detection panel, when necessary – to raise an alarm.

These detectors communicate information to a fire alarm control panel or a software-based building management system through relays or a communication interface. Personnel can receive e-mail status updates, communicating alarm levels, urgent or minor faults.

The multiple warning levels of this system can trigger different responses at different stages of a fire, from controlling air conditioning systems to initiating suppression release. To accommodate specific codes or environments, alarm relays can be set from 0 to 60 seconds.

Suppression

Sprinkler protection in cold storage requires careful design of dry-pipe sprinkler or antifreeze systems. Maintenance retesting of such systems requires even more care. There are three common options: dry, pre-action or clean agent systems and less commonly used anti-freeze treated fire sprinkler systems.

Dry-Pipe Fire Sprinkler System

Dry-pipe fire sprinkler systems offer immediate protection in areas prone to freezing temperatures. These systems use pressurized air or nitrogen to hold pipe valves closed and prevent water from entering the pipes. When a fire triggers operation via the fire sprinkler head(s) activating and exhausting the compressed air or nitrogen, the valves open and water flows through the pipes to the open head(s). Dry systems are used where the area protected by the sprinkler system is subject to freezing. Because dry systems take longer to respond to a fire than a wet system, different design criteria account for the delayed response.

Pre-Action Fire Sprinkler System

When a delayed response is unacceptable, such as a refrigerated or freezer warehouse with contents that would develop high-challenge fires, a pre-action fire sprinkler may be appropriate. Pre-action fire sprinkler systems operate on basically the same premise as dry-pipe fire sprinkler systems. An electric solenoid controlled valve activated by the heat or smoke detection unit via a releasing panel holds back the water. Individual sprinkler heads open to release water onto the areas where it is needed and concentrate the flow of water directly onto the fire after the valve has tripped, flooding the piping system with water. Just as in a wet pipe system, only the fire sprinkler heads exposed to the extreme temperatures from the fire open, spraying water only where it is needed to extinguish the fire.

Like dry systems, pre-action systems normally have only pressurized air in the pipe. But unlike a dry system, merely releasing the air pressure in a pre-action system will not allow water into the pipe. The pre-action valve is controlled by a panel, which can be configured to release water after receiving one or multiple signals.

Clean Agent Fire Suppression Systems

Clean agent systems are waterless,  gas-based flame suppression systems that, when activated, discharge as a gas, reaching all areas of the facility. FE-13 fire suppression systems protect large areas, storage areas for flammable liquids, high ceiling structures, low temperature environments, and turbine enclosures. These systems, which have the lowest toxicity of any clean agent, do not leave a residue behind after usage, which could damage sensitive equipment, or require costly cleanup. FE-13 will not conduct electricity, is non-corrosive and is an environmentally preferred alternative to Halon 1301.

Antifreeze Treated Wet Pipe Fire Sprinkler System

Antifreeze solutions can be added to wet pipe fire sprinkler systems that have a potential to be exposed to freezing temperatures on an occasional or temporary basis. Regardless of which detectors and systems are used in the fire and life safety design in an extreme building environment, all must be networked into one central location. All extreme environments pull from a vast variety of fire protection technologies to protect occupants, stabilize building conditions, and contain and extinguish the fire, if possible.

Mission-critical facilities, such as data and telecommunications centers, must maintain operations without interruption. Mission continuity is assured for facilities through the use of redundant power supplies and mechanical systems, and cutting-edge fire protection systems.

Fire in these facilities can threaten the business and human life. Key to defending against a catastrophe is a sophisticated fire protection system that integrates seamlessly with the entire environment.

Fire protection for mission-critical facilities can be complex and daunting. System designs should be based on a total fire protection approach through which three conditions are met: Identify the presence of a fire, communicate the existence of that fire to the occupants and proper authorities, and contain and extinguish the fire, if possible. Being familiar with all technologies associated with fire detection, alarming, and suppression is important to developing a sound fire protection solution.

Fire Detection Strategies

There are many ways of detecting and suppressing fires, but only a few should be used for mission-critical applications. For example, the main goal of the fire protection system in a data center is to get the fire under control without disrupting the flow of business or threatening occupants.

There are many ways of detecting and suppressing fires, but only a few should be used for mission-critical applications.

Spot Detection

For the purposes of protecting a mission-critical facility, addressable early warning smoke detectors and heat detectors can be an option. Because the airflows are rapid in an area such as a data center, it is important to realize the differences between types of detectors.

Ionization smoke detectors are quicker at detecting flaming fires, such as those commonly found in chemical storage areas, rather than slow, smoldering fires that most typically occur in data centers and telecom equipment spaces. Ionization sensors almost immediately recognize fires characterized by combustion particles from 0.01 to 0.3 microns. However, ionization sensors offer limited or slower capabilities when installed in areas with high airflow – which is often the case in these mission-critical environments.

Photoelectric smoke detectors, however, quickly respond to smoldering fires characterized by combustion particles from 0.3 to 10.0 microns, making these detectors more appropriate for most mission-critical settings.

One solution to detect a broad range of fires quickly would be a multi-criteria detector that uses photoelectric particulate detection in tandem with sensors that detect other products of combustion, such as carbon monoxide (CO) and light (infrared). Together, these signals are cross-referenced by an onboard microprocessor that uses algorithms to “process out” false alarms while enhancing the response time to real fires.

Another solution is to use intelligent high-sensitivity detectors, which are very similar to standard detectors except that they employ a more highly advanced detection method.

High-sensitivity spot detection typically employs a focused laser-based source to achieve sensitivities that are 100 times more sensitive than standard addressable or conventional infrared-based photoelectric smoke detectors. They are designed to respond to incipient fire conditions as low as 0.02% per-foot obscuration to provide valuable time for personnel to investigate the affected area and take appropriate action to mitigate risk.

These detectors are addressable and are able to send information to the central control station, thereby pinpointing the exact location of the smoke. Some can automatically compensate for changes in the environment, such as humidity and dirt buildup. They can also be programmed to be more sensitive during certain times of the day. For instance, when workers leave the area, sensitivity will increase.

High-sensitivity detectors are commonly placed below raised floors, on ceilings, and above drop-down ceilings, as well as in air handling ducts to detect possible fires within the HVAC system.

Aspirating Smoke Detection

Many air sampling smoke detectors can also provide high-sensitivity detection. Some systems can be up to 1,000 times more sensitive than a standard photoelectric or ionization smoke detector and are capable of detecting byproducts of combustion in concentrations as low as 0.00046% per-foot obscuration. This type of detection provides advanced notification so facility managers or other appropriate personnel can intervene and take action before a combustion event becomes disastrous.

An aspiration system works by drawing in smoke through a network of piping via the aspirator (fan). The air sample is then passed through a filter and into the sensing chamber of the detector. Using advanced sensing technology, the detector analyzes the air sample and sends a signal of airborne smoke intensity to a remote or integrated display module and a fire detection panel, when necessary, to raise an alarm.

These detectors communicate information to a fire alarm control panel, a software management system or a building management system through relays or another interface. With some systems, e-mail updates can be sent to appropriate personnel to communicate alarm levels, urgent or minor faults, or other status conditions via relays.

The multiple warning levels of this system can trigger different responses at different stages of a fire, from controlling air conditioning to suppression release. To accommodate specific codes or environments, alarm relays can be set with 0 to 60 second delays.

Fire Suppression Systems

Although smoke detectors primarily alert of a fire condition, in a mission-critical facility, they may also be used to control the release of fire suppression systems. Should a fire occur, suppression systems are the next line of protection and can quickly extinguish the fire with minimal or no effect on the operation. It is important to consider the suppression system to be utilized.

Sprinkler Systems

Sprinkler systems, which are designed specifically for protecting the structure of the building, can be installed in four different configurations: wet-pipe, dry-pipe, deluge, and pre-action. The wet-pipe system consists of a piping system connected to a water source and filled with water so that water discharges immediately from sprinklers activated by a fire. In general, wet-pipe sprinklers are not recommended for mission-critical facilities; however, depending on local fire codes, they may be required.

A dry-pipe system is typically used in areas subject to freezing and consists of piping connected to a water source and filled with air pressure supplied by a compressor. When a sprinkler is activated, the air is expelled first, allowing a special check valve, called a dry pipe valve, to operate. This allows water to flow into the piping and out any open sprinklers. This, too, is not ideal for mission-critical facilities.

A pre-action system is more common in a mission-critical facility. “A pre-action sprinkler system is one effective alternative because of its dual action criteria,” says Ramzi Namek, Director of Engineering for Total Site Solutions, Columbia, Md. “The pipe remains dry until the fire detection system activates a control valve (located outside the data center to avoid damage from leaks), filling it with water.”

It consists of closed-type sprinkler heads connected to a series of piping arrangements. The system has a pre-action valve that prevents the pipes from filling with water during normal times. This valve is held closed electrically, only being released by activation of the detection system (fire detectors) when an electrical signal is sent to the releasing solenoid valve. Upon receipt of the signal, which could be from any of the sensors attached to the system, an electrical mechanism opens the pre-action valve, and the pipelines fill with water under pressure. The system will now function as a standard wet-pipe system. The water tanks are located away from the area, but are readily accessible.

“Another important design consideration to plan for is space for suppression agent tanks. Some suppression agents are stored in gas form; others are stored as a liquid, which can impact the number and size of tanks required,” explains Namek.

Clean Agent Suppression

In addition to sprinkler systems, clean agent suppression systems can extinguish fires in their incipient stage, well before enough heat builds in a room to activate a sprinkler system. When activated, these waterless flame suppression systems discharge as a gas. The gas reaches all areas of the protected facility and leaves no residue to damage sensitive equipment or require costly cleanup. Clean agents suppress fires by many methods, including depleting the area of oxygen, interrupting the chemical reactions occurring during combustion, and absorbing heat.

“Clean agent systems typically use (3M) Novec 1230™, (DuPont) FM-200™, or (Ansul) Inergen. They combine the benefits of clean agent systems and active fire protection with people-safe, clean, environmentally friendly performance,” explains Eric Fournier, Project Manager, Total Site Solutions.

Clean agent suppression systems, protecting both the areas underneath and above the raised floor, are the most common method of fire protection for Class C electrical hazards. “Raised floors bring up some important issues with regard to fire protection in mission-critical facilities,” says Fournier. Spaces beneath raised floors often experience many air changes per hour, which presents a difficult detection design.

“Because raised floors create a completely separate plenum and pose as much of a fire hazard as the numerous pieces of computer equipment situated on the raised floors,” Fournier continues, “they must be protected with the same level of fire protection as the space above.”

These clean agent suppression systems, when controlled by an interface with a high sensitivity smoke detection system, suppress fires without damaging IT equipment, and allow staff to get the facility up and running faster.

Regardless of which detectors or systems are used in the fire and life safety design in a mission-critical facility, all must be networked into one central location. Whether that is a series of panels or a control center, there will be a vast amount of equipment used – hundreds and maybe thousands of devices, depending upon the size of the facility. Programming is the key to how well all the pieces come together. The outcome for a fire and life safety system within a mission-critical system remains: to minimize or prevent a fire event in order to maintain constant operation and protect occupants.

This guide provides an overview of System Sensor fire and smoke detection technologies. It is not a comprehensive overview of all System Sensor products; rather, the objective is to show how System Sensor has detection technologies that are suitable for different fire and environmental scenarios.

Please consult with System Sensor for specific product information, and for notification products and other systems not covered in this guide. Also, consult with your Authority Having Jurisdiction for code applicability before selecting a system.

Conventional Smoke Detectors

System Sensor conventional smoke detectors include the 100 Series detectors and the i³ Series, amongst others. These photoelectric 2- and 4-wire spot-type detectors can include a built-in sounder, thermal sensor, and Form C relay to meet a range of requirements. Conventional detectors specialize in the detection of slow, smoldering fires with particulates in the 0.4 to 10.0 micron range. These detectors have an approximate maximum coverage area of 900 sq. ft. (30 ft. x 30 ft.).

Conventional smoke detectors are a practical choice for typical applications when they don’t require an intelligent device and the primary objective is to protect lives from fire and smoke. For example, they are often ideally suited to general commercial and multi-family residential applications.

Intelligent Smoke Detectors

Many of today’s fire systems are “smart” or “intelligent.” The components of these systems are able to engage in two-way dialogue, analyze complex environments, adjust their own sensitivity levels and make “educated” decisions based on stored data.

One important benefit of intelligent (addressable) smoke detectors is the ability for the panel to pinpoint detector locations for quick identification of detectors that are in alarm, have been tampered with or require maintenance.

System Sensor produces a full line of intelligent smoke detectors, from standard photoelectric smoke detectors (2251B) used in many commercial applications, to a host of specialty detectors, some of which are detailed in this guide.

Aspiration Smoke Detectors

Aspiration smoke detectors draw air into a high-sensitivity sensor through a pipe network to provide Very Early Warning Fire Detection. This approach enables these detectors to protect mission-critical facilities and high-value assets from the faintest traces of smoke – even in highly challenging environments.

The System Sensor FAAST® Fire Alarm Aspiration Sensing Technology (8100) includes unique dual vision sensing technology. This sensor uses an extremely sensitive blue LED to provide Very Early Warning Fire Detection, and an infrared laser to identify nuisances like dust that can cause false alarms and downtime. The detector interprets signals from both sources to provide the earliest and most accurate warning of the widest range of fires available. FAAST includes five programmable alarm levels and ten pre-alert particulate levels, so thresholds can be set to specific site requirements. System conditions are displayed at the user interface and at a fire alarm control panel via relays. With integral TCP/IP Ethernet connectivity, FAAST provides e-mail notification of device status updates and can be monitored remotely via its PipeIQ™ software or a smart phone through any Web browser. FAAST’s remote monitoring capabilities enable facility managers to mount an appropriate response to any situation.

A single FAAST unit can protect up to 8,000 sq. ft. with a wide sensitivity range of 0.00046 to 6.25 %/ft. obscuration. Because FAAST can be installed remotely while sampling points can be run into the protected area through the pipe network, it can be an ideal choice for challenging environments, such as cold storage facilities or medical testing rooms. The pipe network can also be hidden above a ceiling or in a floor cavity to eliminate tampering in public areas or to maintain a facility’s aesthetics while protecting important assets, such as in a museum. And with its ability to provide the earliest, most accurate detection available, FAAST can also be ideal to protect mission-critical environments, such as telecom/data centers and hi-tech fabrication facilities.

BEAM Smoke Detectors

System Sensor single-ended BEAM smoke detectors (BEAM1224 conventional, BEAM200 intelligent) are designed to save time and money and provide better detection capabilities for many open-area and high-ceiling applications. BEAM detectors provide a very wide coverage area – up to 19,800 sq. ft. (330 ft. x 60 ft.) and are well suited for applications where it is difficult to install or maintain traditional spot detectors or where smoke might not reach the ceiling due to stratification.

These detectors include an 8-inch reflector that is mounted opposite the transmitter/sensor, so only one device needs to be wired. They have a wider operating temperature range than typical spot detectors and work well in colder environments, such as cold storage warehouses and sports arenas, as well as other high-ceilinged areas like atria, lobbies, gymnasiums, and factories. BEAM detectors also include a full line of accessories, such as heavy-duty mounting kits, heater kits, long range kits, etc., to help installers meet a variety of application requirements.

Duct Smoke Detectors

A duct smoke detector is a device or group of devices used to detect the presence of smoke in the airstream of ductwork sections of the HVAC air-handling systems used in industrial/commercial facilities. Duct smoke detection not only serves to assist in preventing the spread of toxic smoke and combustion gases, it can also be used to assist in equipment protection applications.

Made to operate in air velocities from 100 to 4,000 feet per minute, System Sensor InnovairFlex™ photoelectric duct smoke detectors (D4120 conventional, DNR intelligent) utilize a pivoting housing that fits both square and rectangular footprints on round or rectangular ductwork. These detectors provide the superior false alarm immunity necessary to reduce callbacks in duct applications that are prone to have nuisance conditions. InnovairFlex detectors also use patented sampling tubes that plug into these often difficult-to-access detectors from the front or back of the device without the need for tools.

The InnovairFlex line includes specialty detectors that are designed specifically for challenging or unique duct smoke applications. The DNRHS high-sensitivity duct smoke detector uses a highly sensitive laser sensor to provide very early warning of fires to protect high-value assets and mission-critical operations from fire and the spread of damaging smoke through air management systems.

NEMA 4-rated InnovairFlex watertight duct smoke detectors (D4120W conventional, DNRW intelligent) are built to operate on rooftops or other challenging applications without the need for bulky or costly enclosures. These detectors can operate in airflow speeds from 100 to 4,000 feet per minute, temperatures from –4°F to 158°F and humidity ranges from 0 to 95 percent (non-condensing). In addition, the watertight, UV-resistant housing provides protection against rain, windblown dust and dirt, splashing, and hose-directed water.

Multi-Criteria Fire Detectors

Intelligent multi-criteria detectors monitor more than one product of a fire in order to achieve higher levels of sensitivity, detect a wider range of fires, or improve accuracy. The Advanced Multi-Criteria Fire Detector (2251-COPTIR) combines four sensing technologies – smoke, carbon monoxide, heat, and infrared – with intelligent detection algorithms that enable the detector to respond very quickly to an actual fire while maintaining the highest levels of nuisance immunity available.

This detector is ideal for challenging applications where ambient conditions have the potential to cause nuisance alarms in typical spot detection technologies or where nuisance alarms can be especially costly or dangerous, such as in theaters, medical facilities, dormitories, senior living centers, financial trading centers, telecom networks and manufacturing facilities.

Another intelligent multi-criteria detector, Acclimate™ (2251TMB), combines photoelectric and 135°F thermal sensor signals to provide early and accurate fire detection. To further enhance its speed and accuracy, Acclimate can automatically adjust its sensitivity within specified parameters. For example, if usage for a protected area varies, the detector will adjust itself to provide the appropriate sensitivity to suit current environmental conditions. Other System Sensor detectors, such as the Advanced Multi-Criteria Fire Detector and FAAST, also utilize Acclimate’s self-adjusting technology.

Heat Detectors

System Sensor 400 Series and 5600 Series heat detectors include combination fixed and rate-of-rise plug-in heat detectors and mechanical heat detectors. These detectors offer a low-cost means for property protection against fire and for non-life-safety installations where smoke detectors are inappropriate.

Heat detectors are appropriate for areas with unsuitable conditions for smoke detectors, including areas that experience rapid changes in temperature or where high ambient temperatures exist, such as storage facilities, garages, mechanical rooms, kitchens and other service areas.

To learn more about how System Sensor fire detectors can be used in a variety of projects and applications, visit systemsensor.com/appguides.

Aspiration detection systems, such as System Sensor FAAST® Fire Alarm Aspiration Sensing Technology, have been traditionally intended for critical applications that count on catching fire in its incipient stage. 

Environments such as telecommunications and financial centers remain the mainstream markets for aspiration where highly sensitive fire detection is necessary to ensure continuity. Clean rooms, computer data centers, laboratories, and other businesses with critical data or property assets, where even a short disruption of business or minimal exposure to smoke could be detrimental, all require incipient fire detection. 

Technology advancements, such as the LED and laser sensing technology in FAAST, offer greater reliability while reducing false alarms. Previously, aspiration detection use was limited to only those environments that could tolerate unnecessary disruptions as a compromise for gaining the peace of mind of being alerted to real emergencies. Vast improvements to the false alarm problem make aspiration more feasible to other environments. More imaginative thinking in the field about how aspiration detection could be beneficial in other applications has further broadened opportunities for installing aspiration in less traditional applications — and for reasons other than just business continuity or asset protection.

Aspiration’s Flexibility

Difficult-to-reach areas and hazardous conditions present challenges for fire protection engineers and installers. Aspiration detection systems can be designed into the fire protection mix to help solve these design challenges. 

Options for designing aspiration detection systems, along with or in place of other fire systems and detectors, can eliminate hazardous situations for maintenance personnel. Aspiration systems can provide a safer working environment, eliminating the need to enter high-voltage or high-ceiling environments to test and maintain detectors. 

Dan Ubelhor, Corporate Engineering Manager for Koorsen Fire & Security in Indianapolis, designs aspiration detection into fire safety systems and appreciates the flexibility of aspiration, especially for testing. “Codes require testing of the detectors, but it is difficult, if not impossible, to test them if they are located in high-area environments,” he says. “Sampling pipes can be installed in any area and extended out to reachable levels where the piping can easily be tested.” Tests can include blowing sample smoke into the piping system.

Ubelhor has designed aspiration systems into air handler units and claims the systems work well in high air flow environments. “A lot of times, normal smoke detectors are not listed for high air flow and may not be able to catch the smoke in high air flow areas. Aspiration detection systems actually draw the air in and are well designed to situate in high air flow movement areas,” he says.

Typically, high air exchange areas have some form of mechanical ventilation to maintain constant or cyclical air flow for heating, cooling or other special environments. Smoke tends to travel with the air flow, hence positioning sampling pipes near the return of an air handling unit or heating/air conditioning unit ensures early detection of particulate in the area.

Ubelhor also uses aspiration systems when designing fire systems for high-ceiling environments, such as atria or warehouses. “Many times we’ll run air sampling systems across the air intakes in high atrium areas in order to increase the sampling volume. This would be done instead of sampling at the ceiling level where the air flow would present a minimum amount of air particles,” he says.

Large volume areas and areas with high ceilings require special design considerations for the pipe network design. Stratification can occur in these places where air temperature may be elevated at the ceiling level as well as a lack of ventilation. In applications where stratification is likely to occur, conventional pipe network sampling may not be effective. 

One method to overcome the stratification problem is to create a vertical sampling pipe in addition to the horizontal pipe network on the ceiling. The vertical sampling pipe has sampling holes at various heights to sample within any stratification layers in the area. Warehouses with high ceilings are a good example of this type of environment — where having multiple pipe configurations at different sampling levels could work well.

Difficult or Dangerous Installations

Scott Golly, Senior Engineer at Hughes Associates Inc. in Baltimore, has also designed aspiration detection into fire systems to overcome positioning difficulties. “A good application for aspiration is when it is difficult to get to the smoke detectors for maintenance,” he says.

UPS battery rooms, for example, do not require the very early detection afforded by aspiration technology, but installing and maintaining smoke or heat detectors above high-amperage UPS batteries can be dangerous. “It’s just an unsafe work environment,” states Golly. “Instead, an aspirating smoke detector can be placed on the wall with an array of sample holes and piping installed above the batteries. A remote sample point for each pipe run can then be extended down the wall, positioned to allow testing and maintenance of the system without putting employees at risk.”

According to Golly, maintenance factors into the application configuration. “Ultimately, the pipes need to be maintained and cleaned. A method of cleaning the pipe that works without climbing over your head is needed. The positioning of the remote sample points is key to accomplishing servicing as well as annual testing without putting anybody at risk,” says Golly. “You can drop a sample point down the wall on the far side of the room, but still make sure that the detection layout on the ceiling is adequate.”

Golly says aspirating detection is also being used more frequently for applications where the environment needing detection is not within the UL listing of a normal smoke or heat detector.

“If smoke detection is preferred by the client in an adverse environment, not heat detection due to the inherent delays associated,” explains Golly, “aspirating system detectors can be placed in a climate-controlled room with the sampling pipes flowing into the adverse climate space. For example, an animal holding building at a zoo may have a climate-controlled electrical closet, yet detection over the animals is still needed where it’s not climate controlled. With care to ensure the sampled air will not adversely affect the detector operation, the detector can be placed in the electrical closet, keeping it within its UL listing and providing smoke detection.”

Sampling Tubes Stay Out of Sight

When it’s more beneficial for the system to be hidden, such as for safety or historical impact reasons, sampling pipes can be in the ceiling or the lighting, typically within capillary tubes. This approach works in correctional facilities, where it’s important to have a vandal-proof system to detect smoking or other conditions without sounding a false alarm.

Aspiration technology with hidden piping is also useful for protecting historical buildings, as well as for the irreplaceable assets inside museums and art galleries. (See Fall 2010 issue of LifeSafety at www.systemsensor.com/ls). Concealing the sampling pipes retains the authentic look and environmental aesthetics of preservation projects, while offering the highest level of protection.

The main pipe network is installed in a ceiling void, and capillary tubes are branched off at regular intervals. These capillary tubes are used to monitor the protected area by projecting through the ceiling covering while the main pipe network remains hidden.

In dirty, industrial environments, such as a spray booth for painting appliances or other products, an aspiration system can be programmed at the highest level of sensitivity to tell the difference between a paint particle and smoke particulate. Aspiration systems do require high maintenance in dirty environments, however.

Local codes and regulations can determine the size and spacing between the sample holes in a network, making them a critical part of any pipe design. These requirements change depending on the type of environment monitored. Local codes and standards take precedence over any parameters suggested for aspiration systems.

Aspiration detection systems provide a vast span of detection. Not only is there flexibility with aspiration systems to move the piping for different applications, but these systems also have unique capabilities to program multiple warning levels. At the most basic level, an aspiration system alerts personnel at the incipient stage of a fire. Other options include sending a signal to the building alarm system or automatically initiating a suppression system if certain pre-set conditions are met.

More than ever, companies want the security of knowing that their assets and personnel are safe from fire. Integrating an aspiration detection system into the overall fire and life safety system can provide quick detection and solve challenges such as positioning, aesthetics, security and life safety in both traditional and unique applications.

Enhancing fire and life safety with the use of very early warning fire detection strengthens protection by enabling proactive response to a fire threat at the earliest possible stage.

Fire and life safety systems have come a long way, consisting of an adept mix of detectors and detection mechanisms integrated to safeguard life and property. Because data, computers, inventory and telecommunications systems drive almost every aspect of our economy, sometimes even higher levels of protection are necessary. High-sensitivity fire detectors that offer very early warning fire detection protect the most critical assets and business operations.

High-sensitivity detectors are often used to monitor critical and high-value infrastructure, equipment and processes where 24/7 continuity needs to be ensured. Providing a proactive approach to fire detection and prevention is crucial to these areas, especially in high-risk and specialty applications, such as clean rooms, hi-tech semiconductor and solar panel fabrication, laboratories, telephone switching centers and computer rooms, and facilities with irreplaceable assets, such as museums. This proactive approach can help facility managers identify and respond to a fire threat at the earliest possible stage, often preventing an actual fire and the associated damage.

Today, the most effective way of covering many of these applications is with highly sensitive Very Early Warning Fire Detection aspiration systems, which can detect potential fires before ignition.

Aspiration Technology

The primary role of an aspiration system is to give adequate warning of combustion particles, so that a fire can be extinguished before serious damage or lengthy interruption of service occurs. Because it provides very early detection, a potential fire emergency can become a simple maintenance task, thus helping to avoid fire damage, asset loss and business disruption.

Many aspirating smoke detectors are highly sensitive, and can detect smoke before it is even visible to the human eye. To elaborate the impact, consider the semiconductor industry, where clean rooms and photo bays have no tolerance for any particle generation. “Even a relatively small fire generates large quantities of particles that have the potential to cause significant damage to sensitive equipment and product,” says Beth Tshudy, Environmental Health and Safety Manager, Analog Devices, Inc., Wilmington, Mass. “If a fire takes place, it is critical that it is detected in its early stages by an aspiration system that measures particle counts and monitors at the delta. For example, an aspiration system can detect particles from a small fire on a circuit board before anyone can see or smell the smoke. The use of aspirating technologies is by far the best detection technology for the semiconductor industry.”

Some aspirating detectors are not recommended for use in unstable environments due to the wide range of particle sizes they detect. Other aspirating detectors can, however, be used in dusty/dirty environments.

One example of such a situation is an application in the oil and gas industry, where there might be a lot of particulates in the air. “Recently, aspiration detection technology was used in a 750,000 square foot building in the Middle East that included manufacturing areas and high rack storage areas,” explains Larry Owen, International Project Director, Dooley Tackaberry, Inc., Deer Park, Texas. “Many factors contributed to selecting aspiration detection, such as the exterior of the building. One side faces an ocean; the other side the desert, exposing it to extreme temperature fluctuations. Because of all these factors, 25 networked aspiration detection systems were used, as opposed to 850 spot detectors, providing a solution that resulted in a much safer environment for the technicians. It saved maintenance costs, and it worked.”

“The benefit is that the aspiration system can be adjusted to accommodate the environmental conditions,” Owen continues.

An aspiration system works by drawing in smoke through a network of plastic conduit piping via the aspirator (fan). The air sample is then passed through a filter and into the sensing chamber of the detector. Using advanced sensing technology, the detector analyzes the air sample and sends a signal of airborne smoke intensity to a remote or integrated display module, and a fire detection panel, when necessary, to raise an alarm.

The system, which typically has both pre-alarm particulate and alarm levels, is integrated with a fire detection panel. Airborne particulate information is presented through a bar graph display, alarm threshold indicators and graphic display. These detectors communicate information to a fire alarm control panel, a software management system or a building management system through relays or a high-level interface. E-mail status updates can be sent to appropriate personnel communicating alarm levels, urgent or minor faults or isolate inputs via relays.

The multiple warning levels of this system can be used to trigger different responses at different stages of a fire, from controlling air conditioning to suppression release. To accommodate specific codes or environments, alarm relays can be set from 0 to 60 seconds.

Not all aspirating smoke detectors are created equal and can be susceptible to nuisance alarms. That is why the System Sensor FAAST® system uses dual source (blue LED and infrared laser) optical smoke detection with advanced algorithms to detect a wide range of fires while maintaining enhanced immunity to nuisance particulates. The blue LED detects extremely low concentrations of smoke. The infrared laser source is used to identify nuisances, such as dust, which can cause false alarms and downtime. Advanced algorithms interpret signals from both sources to meet a single purpose: the earliest and most accurate smoke detection available.

Regulatory Requirements

Although the design of fire protection systems has primarily been based on traditional prescriptive fire codes, there is an increasing emphasis on performance-based codes that address individual environmental requirements. Performance-based design determines the best fire protection system by assessing the function, risk factors and internal configuration and conditions of a specific environment (see “Codes Address Aspirating Smoke Detection”).

Local codes and regulations can determine the size and spacing between the sample holes in a pipe network, making them a critical part to any pipe design. These requirements change depending on the type of environment being monitored.

The detection system must be designed for conditions when the air handling system is either operational or out of service. Periodic maintenance can include processes like changing the filter or occasional pipe maintenance — the frequency and necessity of specific maintenance would depend upon the application and the system. Other system checks may need to be performed in accordance with local or national codes and regulations.

Design

A variety of design configurations can be followed when including Very Early Warning Fire Detection. Although each application will have different airflow patterns, there are basic requirements that must be followed for a good site design. The more information that is obtained up front, the easier the process will be. To aid the design process:

• Understand local codes and standards.
• Gather all relevant information about the site, including the floor plan for the protected space. The floor plan must also include existing or proposed fixtures, fittings, air handlers, vents and other equipment that requires special consideration.
• Determine the uses of the protected area to establish any special requirements.
• Verify the protection level required for the area: standard fire detection, Early Warning or Very Early Warning Fire Detection.

When designing a Very Early Warning Fire Detection system, consider:

1. The airflow characteristics and the air change rate within the room.

2. The coverage area per detector or sample point.

3. The sensitivity required per sampling point.

4. The room size and characteristics: raised floor, tall ceilings, etc.

5. The annunciation of emergency response systems.

6. The activation of mechanical control systems, such as air extraction and suppression systems.

When there is a concern for tampering, such as prisons and public spaces, consider systems that can be mounted in a secure area while air sampling points are located in the protected environment to greatly minimize the potential for tampering. Or perhaps the scenario is a large public area where evacuations can be difficult, like shopping malls, airports or stadiums. In this case, a highly accurate fire detection system that minimizes nuisance alarms and provides various levels of alert is needed to mount an appropriate, informed response to any situation.

Some areas, like cold storage facilities or spaces with high air flow, have environmental conditions outside the tolerance of typical fire detection technologies. Some Very Early Warning Fire Detection systems can be mounted at a temperate, easy-to-access location while sampling points can be located in the extreme environment — enabling reliable fire detection for spaces with challenging conditions.

Including Very Early Warning Fire Detection in the fire and life safety system can downgrade a potential fire emergency to a simple maintenance task. This proactive approach arms the security and fire and life safety personnel with a complete view of a fire event by identifying a threat at the earliest stage of a fire’s progression.

The College Opportunity and Affordability Act, which includes amendments to the federal Jeanne Clery Act, states that schools also must provide “timely warnings” when an emergency or threat is present on campus.

Because minutes can mean the difference between life and death, the new  law now requires campus officials to notify the campus community immediately upon confirmation of a significant emergency, unless issuing the notification would compromise containment efforts. In the case of the Virginia Tech tragedy, for example, two hours passed between the discovery of the shooter’s first two victims in a dormitory and when the university issued its alert.

In addition, the amendment calls for colleges to create policies explaining evacuation procedures and emergency response. Federally funded college and universities would be required to publish fire safety reports yearly, including the cause of campus fires and the number of fires and fire-related deaths.

These efforts would:

• Boost campus safety and disaster readiness plans

• Help all colleges develop and implement state-of-the-art emergency systems and campus safety plans, and require the Department of Education to develop and maintain a disaster plan in preparation for emergencies

• Create a National Center for Campus Safety at the Department of Justice

• Establish a disaster relief loan program to help schools recover and rebuild following a disaster

The new law compels universities and colleges to use state-of-the-art methods and technologies to improve campus security. The most integrated solutions are emergency communications systems (ECSs), which are becoming an integral part of both emergency and non-emergency communications for schools and organizations of all sizes. This is because an ECS is not simply a loudspeaker system; communication is only part of the solution. True ECSs involve a lot more than text messaging and intercoms. They involve integrated response to emergencies at every level of the school — a communications and emergency management tool.

ECSs can broadcast live, up-to-the minute emergency information to everyone in a building, campus, or multiple facilities spread across a large area to prevent injuries and save lives.

In addition to crime alerts, an ECS can warn people of severe weather, such as tornados or hurricanes; class cancellations because of a power failure, a gas line or water main break, or other utility problems; and biological and radiological accidents, or hazardous spills.

Mass notification is a relatively new concept for the life safety community, which arose from the inability of emergency management personnel to communicate with and direct building occupants during emergencies. Since the publication of the Unified Facilities Criteria, a 2002 U.S. Department of Defense program outlining the design, operation and interfaces required for mass notification in military facilities (the final version for mass notification was approved in 2008), many U.S. military facilities throughout the world have installed mass notification systems (MNS). In the private sector, the demand for MNS has been rising steadily since Sept. 11, 2001. In response, the 2010 edition of NFPA 72 greatly improves design direction for the layout of intelligible voice systems.

The National Fire Protection Association introduced MNS criteria in the annex of the 2007 edition of NFPA 72, where it was presented for explanatory purposes only. After the 2007 edition of NFPA 72 was published, the NFPA Standards Council created a technical committee to develop a new chapter for the 2010 edition. Released in October 2009, the 2010 edition of the National Fire Alarm and Signaling Code provides emergency communication system (ECS) requirements (which include MNS) in chapter 24.

Because the overall purpose of an ECS is to save lives and minimize injuries during emergencies, it is imperative for individuals to clearly understand voice messages delivered over facility-wide communications systems. As a result, the new ECS chapter includes intelligibility requirements for voice systems.

Intelligibility and Acoustically Distinguishable Spaces

What is intelligibility? Speech intelligibility is the measure of the effectiveness of speech. The measurement is usually expressed as a percentage of a message that is understood correctly. The 2010 edition of NFPA 72 defines intelligible (Section 3.3.126) as being capable of being understood, comprehensible and clear; intelligibility (Section 3.3.125) is the quality or condition of being intelligible.

The first step in designing an intelligible voice system is to determine what type of ECS the building owner desires. The voice communication system will often include in-building fire EVACS, in-building mass notification and a paging system to meet the day-to-day operational objectives. Chapter 24 of the 2010 code permits all three systems to be combined, resulting in an ECS.

Voice intelligibility requirements refer to “acoustically distinguishable spaces” (ADSs). This term, which is new to the 2010 edition of NFPA 72, originated from research conducted by the Fire Protection Research Foundation on how to design and measure intelligibility.

Section 3.3.2 defines an ADS as “distinguished from other spaces due to acoustical, environmental or use characteristics, such as reverberation time and ambient sound pressure level.” An ADS allows the building to be divided into definable spaces so the system designer can identify which spaces in a building may require voice intelligibility.

Not all areas of a building are required to have voice intelligibility. In fact, some building spaces may only require tone signaling, whereas other spaces may require no occupant notification at all. Per Section 24.3.1, an ECS must be capable of reproducing prerecorded or live messages with voice intelligibility in accordance with Chapter 18. Section 18.4.10.1 requires the system designer to identify ADSs during the planning and design of the ECS, and according to Section 18.4.10, each ADS may or may not require voice intelligibility.

Designing an intelligible voice system does not lend itself to prescriptive design as visible notification appliances do. Speech intelligibility is not a physical quantity measured in feet, amperes, volts or even decibels. It is highly recommended that designers refer to annex D to plan, design, install and test voice communication systems.

The majority of the annex contains recommendations for testing voice system intelligibility. Designers who are new to voice systems may want to consult other sources, such as the National Institute for Certification in Engineering Technologies (NICET) program for Audio Systems or the National Electrical Manufacturers (NEMA) Emergency Communications Audio Intelligibility Applications Guide. Due to the complexity of designing a voice system, it may also be useful to use a software design program to predict voice system intelligibility before installation. These software programs model acoustic properties for specific environments and speaker configurations.

Design Factors to Consider

Several factors to consider when designing a voice system are: signal-to-noise ratio, frequency response, harmonic distortion and reverberation. Therefore, properly designing an intelligible voice system requires knowledge of the acoustical factors that influence intelligibility, such as the anticipated background noise level, occupancy type and architectural design of the space. The acoustical properties of the materials on the walls, floors and ceilings significantly impact the intelligibility of the space. Achieving voice intelligibility may be difficult, or even impossible, depending on the architectural design.

An important step in designing a voice system is determining the effect of the environmental and acoustical properties on speaker placement. In the past, fire alarm voice systems typically had too few speakers. It is important for designers to require the right speaker quantity and placement to ensure proper intelligibility and audibility (decibel (dB) rating).

Section 24.4.1.2.2.1 requires the following be met for layout and design:

1) The speaker layout of the system shall be designed to ensure intelligibility and audibility.

2) Intelligibility shall first be determined by ensuring that all areas in the building have the required level of audibility.

3) The design shall incorporate speaker placement to provide intelligibility.

A rule of thumb is to install speakers in rooms with 10- to 12-foot ceiling heights at intervals measuring twice the ceiling height and 1 watt per 750 to 1,000 square feet. The ambient noise level of the space served by the speakers must be considered to ensure speakers produce the correct levels of intelligibility and audibility. Ideally, 10-15 dBA above average ambient sound levels provide adequate intelligibility.

For the effects of speaker distance and wattage on audibility, see Figure 1.

Avoid installing wall-mounted speakers in large rooms with ceilings up to 15 feet in height as this contributes to more reverberation due to longer distances to opposing walls. Also avoid installing speakers on ceilings that are greater than 20 feet in height, especially in rooms with highly reflective walls.

Testing Methodologies

Following installation, the system must be tested for intelligibility. It is important to note that speech intelligibility testing is usually described as predictions, not measurements. Most instrument users, however, refer to the results as measurements. Because portable intelligibility meters are most commonly used for the accurate test results, the results are usually referred to as measurements to avoid confusion.

In accordance with D.2.1.1.1 in the annex, the recommended method for measuring intelligibly is the Speech Transmission Index (STI) test protocol. STI is a quantitative methodology for measuring intelligibility. Another method, the Common Intelligibility Scale (CIS), was created to map all methods to the same scale so that all different results could be compared. In accordance with section D.2.4.1, the intelligibility of an ECS is considered acceptable if at least 90 percent of the measurement locations within each ADS have a measured STI of not less than 0.45 (0.65 CIS) and an average STI of not less than 0.50 STI (0.70 CIS).

Because clearly understanding a live or recorded voice message during an emergency is essential for the safety of a facility’s occupants, planning and testing is crucial. The best methodology to ensure a message is clear and intelligible in all situations is to measure intelligibility.

Founded 26 years ago, Phoenix Children’s Hospital is one of the 10 largest children’s hospitals in the nation. The hospital currently covers over 40 pediatric specialties and provides health care to some of the sickest children in Arizona.

In order to meet the pediatric bed needs and health services requirements of a rapidly expanding metro Phoenix population base, the hospital began a $588 million expansion and renovation of its facilities in 2008. A main goal of this build-out will be to increase licensed beds from the current 345 to 626 by 2012.

Amongst other additions and renovations, the campus will feature a new 685,000 square foot, 11-story patient tower, three new parking structures adding about 1,750 parking spaces, a covered playground for patients and their siblings, and an 18-unit Ronald McDonald House to provide housing for patients’ families. In addition, the entire build-out will be supported by a new 30,000-squarefoot, two-level central energy plant and logistics building.

Once all renovations are completed, Phoenix Children’s Hospital will be the largest freestanding children’s hospital in the nation.

Providing a fire protection system for such a large project will be a complicated and difficult task. The project requires installing the latest, most advanced fire protection technology available for the renovated and new structures, such as the patient tower, and integrating this new technology with the hospital’s legacy systems in order to create a single, cohesive system that provides the highest level of fire protection possible.

Appropriately, the process for choosing the fire system contractor was very demanding. As Tim Snow, general manager of Detection Logic Arizona, put it, “To win this job, the contractor would have to provide the right credentials, the right product offering, and the ability to support the system in the future.”

The Right Credentials

The first stage of the process began in March 2008 with the fire alarm Request for Qualifications (RFQ) sent out to several vendors representing each of the three fire system manufacturers approved for the project. The RFQ included a general overview of the project and a proposed project schedule.

Key information requested in the RFQ included company size, engineering/staff qualifications, completed hospital or similar projects, and project backlog through the proposed Phoenix Children’s Hospital project schedule. Based on the information they provided in vendor responses to the RFQ, the project management team winnowed the candidate list down to three vendors, each representing one of the approved manufacturers. Mainly due to its engineering qualifications and expertise and its ability to demonstrate several successful installations of fire systems in large hospitals, the team chose Detection Logic as the vendor to represent NOTIFIER^®, an approved manufacturer.

The Right Products

Even for Detection Logic, which has extensive experience in installing fire systems for large applications, winning the project came down to several other factors — most significantly its system design proposal.  The winning submittal had to demonstrate that the design and product selection could best meet all the challenging technology and performance requirements of Phoenix Children’s Hospital while keeping system, installation, and ongoing operational costs down.

For example, the existing fire system for Phoenix Children’s Hospital is based on Edwards Systems Technology (EST) products. As a NOTIFIER vendor, Detection Logic would be required to integrate any proposed NOTIFIER technology with the existing EST-based fire system.

To integrate the legacy EST and new NOTIFIER systems, Detection Logic proposed connecting each panel through an Echelon^® fiber optic network to an ONYXWorks™ workstation from NOTIFIER in a UL-864-listed configuration.

“The ONYXWorks Monitoring and Integration System is the only system available capable of integrating all of Phoenix Children’s Hospital legacy and proposed systems,” said Fred Lovato, engineering manager at Detection Logic. For Phoenix Children’s Hospital, these systems could include fire alarm systems, security systems, card access systems, CCTV systems, central station receivers for outlying buildings with no connectivity, and any systems with dry contacts that must be monitored.

Along with the Echelon backbone with ONYXWorks, the proposal included NOTIFIER network panels and detection and notification devices from System Sensor, including intelligent photoelectric smoke detectors, SpectrAlert^® Advance chimes and strobes, and speakers and speaker strobes for voice evacuation. “With their ability to communicate clear, intelligible messages that meet the updated NFPA intelligibility requirements, SpectrAlert Advance speakers and speaker strobes are our device of choice for voice evacuation systems designed to protect patients and children,” said Lovato.

All proposed products were also selected for their ability to be quickly and easily installed and maintained. All SpectrAlert Advance products provide plug-in designs with universal mounting plates to speed and simplify installation. For example, the design called for over 1,200 speaker strobes. As the only speakers and speaker strobes available that provide plug-in designs, the SpectrAlert Advance devices not only speed and simplify installation across large projects, but also reduce labor and material costs associated with ground faults caused by pinched or crushed wires.

The Right Support

In addition to the system design proposal, Detection Logic provided Phoenix Children’s Hospital with information on how they would support the system.

Snow said, “No matter how good the installation of the system, the overall effectiveness is dependent upon the knowledge passed on to the end user.” Maintaining high-performing, cost-effective day-to-day operations of the system would be dependent on Phoenix Children’s Hospital personnel.

Consequently, Detection Logic proposed a range of approaches to enable Phoenix Children’s Hospital to operate and maintain the system effectively, including providing constant training throughout the installation of the system, labeling devices based on Phoenix Children’s Hospital input, and designing a user-friendly system interface.

In addition, Detection Logic has a fully staffed customer service department to provide ongoing support after completion of the installation, including 24/7 emergency service response, Web-based inspections and service reports, prescheduled inspections, and ongoing end-user training. These and other services will help Phoenix Children’s Hospital keep its fire system performing optimally, manage costs, and provide the highest level of protection available for patients and staff.

The Winning Bid

Ultimately, Detection Logic won the project by clearly communicating how the company and the proposed system could meet all the needs of Phoenix Children’s Hospital. As Terry Manning of Rolf Jensen & Associates, Inc., the consulting engineer over the entire project, reported, “…the fire alarm system…has been reviewed and accepted without comments. It is one of the best packages I have seen in a long time.”

Imagine it’s Saturday night at a packed entertainment venue. The dance floor is full of people dancing to a popular national DJ with music synched to multi-colored laser and light effects, and several private rooms are at full capacity hosting VIPs, fundraisers or other private parties. The rope line for the public dance club stretches a block down the street, with people waiting up to an hour for a chance to spend a memorable evening out with friends.

Then, a smoke effect designed to enhance the laser light show reaches a standard smoke detector set above the dance floor. Suddenly, the entire complex goes into full fire alarm…the music and effects are cut off and replaced by the blare of a fire alarm, fire strobes and floodlights. Patrons rush toward the exits and out onto the busy street.

More than an hour later, fire services have checked out the building. There’s no fire and no damage. But now the rope line is empty, evacuated patrons have moved to a club down the strip and angry party hosts are demanding their money back from the club’s management. In all, the club has lost thousands of dollars as the result of a single nuisance alarm.

Scenarios such as this can be quite common. Traditional fire detection technologies, which excel at detecting fires and providing adequate escape times in most applications, often struggle to maintain appropriate fire sensitivity and accuracy for atypical and challenging applications. Because of this, venues with persistent nuisance conditions, such as theater smoke and fog effects, must make difficult and costly decisions about how to provide the high-quality entertainment experience their customers have come to expect, while maintaining the highest level of safety possible.

In fact, this is the exact issue that was faced by one popular nightclub. The following case study shows how advanced fire detection technology enabled this club to overcome its difficult and costly fire detection challenges.

Case Study: The Rumba Room

The Rumba Room is an upscale Hollywood nightclub. Part of a multi-building, multi-story entertainment complex, this 25,000 square foot, 1,000-patron capacity Latin dance club boasts two levels and two dance floors featuring state-of-the-art sound and lighting, including fog and smoke effects.

Unfortunately, the club’s theatrical smoke set off the facility’s smoke alarms on an almost nightly basis. To make matters worse, the smoke would trigger a full-blown alarm that would require the evacuation of nearly a quarter of the entire entertainment complex, including the restaurant below the club.

Like the Rumba Room’s situation, there are many fire system applications that stretch the capabilities of traditional fire detection technologies beyond their capacity — either because nuisance conditions are present or because even a small amount of downtime relating to nuisance alarms can have devastating financial effects. That’s because fire detection devices must balance two competing needs: rapid response and accuracy.  Typically, increasing performance in one of these factors reduces performance in the other: Improving response times increases nuisance alarms. Conversely, reducing nuisance alarms increases response times.

Newer construction and furnishing materials exacerbate this problem by increasing fire acceleration, which reduces escape times. Faster-burning environments require higher sensitivity from their fire detection systems to allow proper egress and better property protection.

Figure 1

Problems arise when an application demands too much of a detector in either sensitivity or accuracy. Sometimes, this imbalance can cause such poor performance that the fire detection system itself can become a liability.

This was certainly the case with the Rumba Room.

The fog and smoke effects were demanding a level of accuracy from the traditional photoelectric detectors over the dance floor that was well beyond normal.

With each alarm resulting in one to two hours of downtime, including evacuation, fire department arrival and walkthrough and clearing of smoke, lost revenues from each instance could exceed tens of thousands of dollars.

The Rumba Room, after purchasing and experimenting with several different fog and smoke machines with similar results, was forced to receive special permission to set all of its smoke detectors to supervisory mode. This required independent verification of a fire before sounding an alarm, ultimately slowing fire response and incurring additional liability.

Advanced Technology Improves Detection

Then, in 2009, Callide Technical of San Dimas, Calif., was contracted to upgrade the fire safety system of the entire entertainment complex. The Rumba Room posed a particular challenge for Callide.

“With all the fog and smoke effects, the existing photoelectric detectors were constantly going into alarm,” said Tom Johnson, a Callide Technical principal. Callide agreed, however, that maintaining the fire alarm system in supervisory mode was an unsatisfactory solution in terms of liability risks and costs, and the resulting delay in fire response.

Callide proposed installing the System Sensor Advanced Multi-Criteria Fire Detector, branded as IntelliQuad™ through Notifier^®, because of its ability to quickly respond to actual fires while maintaining high immunity to nuisance conditions.

How It Works

The Advanced Multi-Criteria Fire Detector combines four detection methods in a single housing to measure all four products of a fire — heat, smoke, carbon monoxide, and light. If one of the sensors detects a fire condition, the onboard intelligence verifies the condition with another sensor before generating an alarm.

These four sensors enable the detector to respond to multiple fire types in a wide range of applications and reject nuisance conditions. The detector includes a powerful central processing unit that enables it to process intelligent algorithms to provide extended drift compensation and to vary sampling rates, alarm delay and sensitivity based on environmental readings. The result of years of research and then extensive testing, this dynamic adjustment allows the detector to normally operate at a very high immune level and then become very sensitive to fires once it senses the proper characteristics.

For example, the baseline photoelectric sensitivity might be set to alarm at particulate concentrations of 4 percent per square foot. But unlike a regular photoelectric detector, the Advanced Multi-Criteria Fire Detector can ignore particulate concentrations well beyond 4 percent if no other fire conditions are present. At the same time, if other fire conditions are present, such as CO or heat, the detector doesn’t wait until 4 percent concentrations are present; it can respond more quickly.

Correct Detection Brings Results

The Rumba Room agreed that the decrease in lost revenues and liability and increase in fire response times justified the use of the more advanced technology, especially if it would allow them to operate the club with the smoke and light effects that contribute significantly to its unique ambience and appeal.

Callide installed about 25 Advanced Multi-Criteria Fire Detectors to cover the dance floor areas on both levels. Installers wired the detectors like any other smoke detector. A small amount of additional programming set the detectors at the correct sensitivity level for the environment.

“Labor costs were basically a wash,” said Johnson. “While the installed cost for these detectors was about 15-20 percent more than a typical photoelectric detector, the Rumba Room was losing more money in an hour of downtime than 50 times the cost difference.”

Once installation was completed, the Rumba Room was able to return all of its detectors to alarm from supervisory. And what happened with the frequent nuisance alarms?  Johnson concluded, “These detectors have been operating for several months now without a single nuisance alarm.”

Related stories:
Advanced Multi-Criteria Fire Detector: Ideal Applications
Research Aims to Increase Photoelectric Detectors’ Sensitivity to Flaming Fires