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Fire Service Features of Buildings and Fire Protection Systems Occupational Safety and Health Administration U.S. Department of Labor OSHA 3256-07N 2006 Contents Chapter 1 Introduction [PURPOSE] [SCOPE] [A FIRE SERVICE PRIMER] [FIRE SERVICE CHALLENGES] [MANUAL ORGANIZATION AND USE] [TERMINOLOGY] [GLOSSARY OF ACRONYMS AND TERMS] Chapter 2 Building and Site Design [GENERAL] [FIRE APPARATUS ACCESS] [PREMISES IDENTIFICATION] [FIRE HYDRANTS] [FIREFIGHTER ACCESS] [HAZARDS TO THE FIRE SERVICE] Chapter 3 Sprinkler Systems [GENERAL] [ZONING] [WATER SUPPLY CONTROL VALVES] [FIRE PUMPS] [PARTIAL SPRINKLER SYSTEMS] Chapter 4 Standpipe Systems [GENERAL] [FIRE HOSE CONNECTIONS] [DESIGN PRESSURE] [PRESSURE REGULATING DEVICES] [STANDPIPE ISOLATION VALVES] [OTHER DESIGN ISSUES] Chapter 5 Fire Department Connections [GENERAL] [QUANTITY] [INLETS] [LOCATION] [POSITION] [MARKING] [TEMPORARY CONNECTIONS] Chapter 6 Fire Alarm and Communication Systems [GENERAL] [ZONING AND ANNUNCIATION] [GRAPHIC DISPLAYS] [FIRE DEPARTMENT NOTIFICATION] [VOICE ALARM SYSTEMS] [FIRE DEPARTMENT COMMUNICATIONS SYSTEMS] [FIRE COMMAND CENTERS] Chapter 7 Other Systems [FIREFIGHTER EMERGENCY POWER SYSTEMS] [FIREFIGHTER BREATHING AIR SYSTEMS] [FIREFIGHTER RADIO SIGNAL RETRANSMISSION SYSTEMS] [SMOKE CONTROL SYSTEMS] Appendix [Sources of Referenced Standards and Information] [OSHA Assistance] [OSHA Regional Offices] [Table of Contents] Chapter 1 Introduction PURPOSE The purpose of this manual is to increase the safety of building occupants and emergency responders by streamlining fire service interaction with building features and fire protection systems. The information in this manual will assist designers of buildings and fire protection systems to better understand the needs of the fire service when they are called upon to operate in or near the built environment (figure 1.1). To put this another way, architects and engineers create workplaces for firefighters. Designs can be tailored to better meet operational needs, thereby reducing the time it takes to mitigate an incident. The guidance in this manual is expected to decrease the injuries to responding and operating fire service personnel. When an incident can be mitigated faster, there is less time for the hazardous situation to grow in proportion. With less potential exposure, employees occupying buildings will be afforded greater protection from fire incidents. Employee occupants as well as fire service employees will realize the benefits of this manual in terms of safe working conditions as intended by the Occupational Safety and Health Act of 1970. The codes and standards governing buildings and fire protection systems are well understood by designers. However, many portions of these codes and standards allow design variations or contain only general performance language. The resulting flexibility permits the selection of different design options. Some of these options may facilitate fire service operations better than others. The particular needs and requirements of the fire service are typically not known thoroughly by persons not associated with these operations. This manual discusses how the fire service interacts with different building features and it suggests methods for streamlining such interaction. To provide the most effective protection, fire service personnel should be considered as users of building features and fire protection systems. While far less frequent than mechanical events or other failures, fire can cause greater destruction in terms of property loss, disruption of operations, injury, and death. Designers routinely consider the needs and comfort of building occupants when arranging a building's layout and systems. Within the framework of codes and standards, design options may be exercised to benefit a particular owner, tenant, or user. For example, a building code would typically dictate the minimum number of lavatories and water fountains. However, the location, distribution, and types of such facilities are left to the designer in consultation with the client.  (Fig. 1.1) Commercial building fire at night with multiple exposures. [Table of Contents] SCOPE This manual is to be used voluntarily, as a companion to mandatory and advisory provisions in building codes, life safety codes, fire codes, safety regulations, and installation standards for fire protection systems. The material contained in this document focuses on ways that building and fire protection system designers can contribute to the efficiency of fire suppression operations. This material is applicable to all fire service organizations, including fire brigades and fire departments. Many of the considerations in the following chapters will also help during responses for other emergencies, such as hazardous materials releases, emergency medical care, non-fire rescues, and terrorist events. Users of this manual must understand its limitations. It is directed to designers of buildings and fire protection systems to help them build on existing codes and standards to assist the fire service. For example, the topic of emergency radio communications can be extensive; however, its treatment here is limited to the equipment in buildings that can support radio communications. Likewise, there are entire standards and books written about sprinkler, standpipe, and fire alarm design. However, this manual covers only portions of those systems with which the fire service interacts and suggests design details that will help streamline or support fire service operations. [Table of Contents] A FIRE SERVICE PRIMER This section will give those outside the fire service a basic understanding of how the fire service operates during an emergency. It will also familiarize them with the varying capabilities and organizations involved in fire fighting. Fire service organizations can be classified as career, volunteer, or a combination of both. Career staff members are paid for their work, while volunteer members are unpaid. Combination organizations have both career and volunteer staff. Career organizations typically serve the larger, more urban or industrial settings, although many smaller cities or towns will have a full or partial career staff. Volunteer organizations are usually found in more suburban or rural settings, although some serve densely populated areas and have very high emergency response rates. Another way to categorize fire departments is by whether fire stations are staffed with personnel ready to respond. Most career organizations have personnel who remain in the station while on duty. However, "call firefighters" are paid on a per-response or hourly basis and do not remain in their station awaiting emergency calls. Most volunteers respond from home or work when they are alerted to an emergency. On the other hand, there are organizations that have volunteer personnel staffing their stations on shifts or even living in the stations. Another fire service organization is the industrial fire brigade. This is an organized group of employees specifically trained to provide fire suppression, and perhaps related emergency activities, for a specific employer. Members may be dedicated full time to emergency operations, or emergency response may be a part-time, collateral duty.  (Fig. 1.2) A view from above of both a pumper (top) and an aeriol apparatus (bottom) in this case a platform type of aerial.  (Fig. 1.3) During initial operation at this structure, the first arriving engine crew is already using a fire lane, a fire hydrant, the fire department connection, and the key box. Interior operation will soon involve the alarm system, stairways, standpipe system, and other building features. A pumper apparatus normally carries hose, a pump, and a small water tank. Together with its personnel, this is called an engine company. Their main responsibility is to deliver water to the fire. Initially, the engine company may operate using the water available in their tank; however, any incidents other than small exterior fires will typically require that a continuous water supply be established. This is done via hose lines carrying water from a source of supply (fire hydrant, lake, pond, temporary basin) to the on-board pump, which then boosts the pressure to hose lines or other devices attacking the fire. An aerial apparatus is typically equipped with a long aerial ladder or elevating platform on top, an assortment of ground ladders, and many power and hand tools. Together with its personnel, this is often called a truck (or ladder) company. They are responsible for all support functions, including forcible entry, search, rescue, laddering, and ventilation. If aerial apparatus is not available, these truck company functions must be performed by another unit. There is also an apparatus called a “quint.” Each of these vehicles is equipped as both a pumper and an aerial apparatus to perform either function. If provided with adequate staffing, and positioned properly at an incident, quints can perform both functions. Upon arrival at an incident, firefighters must handle many tasks. Standard operating procedures should enable firefighters to quickly assess the situation, and initially arriving units to go into operation (Figure 1.3). Rescuing of occupants is the first priority, followed by confining and extinguishing the fire. In some cases, firefighters must stop the fire before proceeding with rescues. Incident command begins with the rapid gathering of information by the first arriving officer. This is called “size-up.” Incident command expands as additional units and chief officers arrive. Commanders must base strategies on the limited information available at any given time regarding the fire, the building, and the occupants. As they receive additional information, commanders should revise their strategies. As needed, they can call for additional resources. Units from another jurisdiction or district that respond are referred to as “mutual aid” units. As the fire incident is brought under control, salvage, overhaul, and investigation activities take place. These activities, although dangerous and important, are less time-sensitive. As a result, they are less of a consideration for building and fire protection system designers. [Table of Contents] FIRE SERVICE CHALLENGES Fire service operations take place in stressful, time-sensitive environments (Figure 1.4). Delaying operations, even slightly, especially during the critical initial phase when the first arriving resources are committed, can adversely affect subsequent operations and the outcome. Delays caused by poorly located fire hydrants, confusing alarm information, ineffective communication systems, or inaccessible valves will have a ripple effect on the other portions of the operation. During these delays, the fire will be growing exponentially. Members of the fire service perform their functions during all times of the day or night, in any weather conditions, and frequently in unfamiliar environments. Their work environment is dangerous, mentally stressful, and physically exhausting. Decisions must often be made without an ideal amount of information, due to the many unknowns on the fireground (such as what is on fire, how much is burning, where the fire is spreading, and where the occupants are located). These factors stack the deck against the safety of firefighters. Even simplifying the firefighters' job in small ways will increase the level of safety for them, and thereby for building occupants. Design features that save time or personnel can make a great difference. Any feature that provides additional information regarding the fire, the building, or the occupants, as well as any method to speed the delivery of this information also helps. Pre-incident plans (often called “preplans”) are documents prepared by fire departments to assist in emergency operations in specific facilities. They should contain the location of, and information about, the fire protection features discussed in this manual. Preplans are usually prepared and maintained by the unit that normally responds first, or is "first due," to a particular facility. One could argue that some of the considerations in this manual are not necessary if the fire department prepares thorough preplans. However, the best pre-incident planning cannot overcome situations where the first due unit is committed on another response, out of position, or out of service. Nor can it foresee changes in personnel. It is simply unrealistic to count on all responding personnel to be aware of the pre-incident plan. Pre-incident planning makes sense but it will always have limitations. Fire departments and firefighters that are more familiar with features of buildings in their response area are better prepared to deal with fires and other emergencies. Designers can assist in pre-incident planning by providing copies of building and system plans (paper or electronic) to the fire service after first seeking permission from the building owner.  (Fig. 1.4) Firefighters arriving at a high-rise fire. During this operation, firefighters will interact with most of the features discussed in this manual. To successfully mitigate an incident of this nature, firefighters must make many decisions rapidly, and carry out various operations simultaneously. Time saved due to design with the fire service in mind will translate into increased firefighter and occupant safety. [Table of Contents] MANUAL ORGANIZATION AND USE Each chapter of this manual includes a narrative describing the specific building feature and how the fire department interacts with it. Boxes, entitled “Considerations,” highlight specific items that a designer should consider for each topic. Photos and diagrams illustrate both good and bad examples of concepts and recommendations. Although this manual contains generic considerations, designers should seek and follow the advice of the fire service organization serving each project they work on. In some cases, the fire department will have statutory authority to take part in the plan review, permit process, and inspections of these facilities or to approve some features of the building or site. In any case, it is wise to also include the fire service at an early stage in the design process, when changes are easier and less costly. There are many ways for the fire protection community to disseminate or incorporate the information in this manual. Simply handing it out to designers is a great start. Developing a handout based on this document that is specific to a particular jurisdiction is another good strategy. The recommendations can also serve as a basis for local code amendments which carry the force of law. Many of the recommendations in this manual cost nothing to implement. They simply provide direction in cases where the model codes or consensus standards allow options. Designers can implement these recommendations directly, in consultation with the fire department. Other recommendations in this manual may carry costs, depending on the particular codes adopted in a given jurisdiction. In such cases, those who would be affected by these costs should be consulted. Codes and standards typically include a clause that permits the code official to allow alternatives to strict compliance, as long as the prescribed level of safety is not diminished. In some cases, a higher level of safety for firefighters can be achieved through this process. For example, a voluntary radio repeater system may provide more protection (and may also be less costly to install) than a code-required firefighter communication system. Equivalent alternatives should be documented along with justification. This manual may also serve as a resource for those interested in improving codes and standards for building or fire protection system design. While current codes in the U.S. provide for firefighter safety, much more remains to be accomplished. For instance, building codes in the U.K. have specific fire service provisions, such as dedicated, protected fire stairs and elevators. Streamlining and simplifying fire service operations should be considered an integral part of the overall fire safety framework for the built environment. [Table of Contents] TERMINOLOGY The terminology used in this manual is as generic as possible, just as it is in the standards of the National Fire Protection Association and the International Code Council. Many variations in terms will be encountered in different areas of the U.S. or in other countries. For example, this manual uses the term “aerial apparatus” to describe a fire service vehicle with a long, aerial ladder. Yet, in this country alone, other terms used to describe the same vehicle include: “truck,” “ladder,” “aerial,” “ladder truck,” “tower,” or “tower ladder.” Or, in some cases, the same terms could be used to describe a particular aerial fire apparatus. Similarly, in some areas the term “truck” refers only to aerial apparatus, while in other areas this term could also include pumper apparatus. In another example of potentially confusing terminology, fire apparatus drivers in some areas of the country are referred to as “engineers.” Consider the situation of an architect speaking to a fire officer in an area where this terminology is used. You can easily see how the fire officer could use the term “engineer” to mean a driver, while the architect interprets the term as a building design engineer. The editions of the codes and standards referenced in this manual are not included. The information and requirements referenced in this manual are from the latest editions available during the manual's development in 2004. Subsequent revisions to these codes and standards may change the sections or the requirements referenced. The editions adopted by local or state laws in a given jurisdiction may vary. [Table of Contents] GLOSSARY OF ACRONYMS AND TERMS [Table of Contents] Chapter 2 Building and Site Design GENERAL The faster the fire service can respond, enter, locate the incident, and safely operate in a building, the sooner they can mitigate an incident in a safe manner for themselves as well as occupants. This chapter contains guidance on this topic for both building site layout and interior design features. Those preparing design documents such as site plans, civil plans, foundation plans, and architectural layouts would typically use this information. Building designers desiring to locate fire protection systems features should consult the appropriate chapters of this manual for further guidance. [Table of Contents] FIRE APPARATUS ACCESS Properly positioning fire apparatus can be critical at a fire scene. In particular, placing aerial apparatus is critical for positioning of the aerial ladder or elevating platform, which is mounted on top of these vehicles (Figure 2.1). Pumper apparatus also need to get close enough to the building to facilitate hose line use. The location of other specialized apparatus, or small vehicles, such as chief's cars or ambulances, should only be of particular concern to the designer of unusual facilities. For instance, a sports arena may need to be designed for entry of ambulances but not fire apparatus. Many structures are situated on public streets that provide fire fighting access. Others, which are set back from public streets, have private fire apparatus access lanes or “fire lanes,” for short. These enable fire apparatus to approach the building and operate effectively (Figure 2.2). Fire lanes can be dedicated to fire service use, or can serve ordinary vehicular traffic as well. There are many considerations for both public roads and fire lanes: clear width, clear height, length, turn radius, arrangement, distance from the building, and paving materials. In all cases, the most stringent practicable dimensions should be considered for design, since future apparatus purchases or mutual aid apparatus from other jurisdictions may exceed the specifications required in a given jurisdiction at any given time.  (Fig. 2.1) Good aerial apparatus access at an apartment fire. This fire lane is wide enough to allow passing even when aerial outriggers are extended, and it is located a proper distance from the building to facilitate aerial operations.  (Fig. 2.2) Fire lane dimensions, reprinted with permission from the NFPA 2003 Uniform Fire Code Handbook, © 2003, National Fire Protection Association, Quincy, MA. Minimum building access for fire apparatus is a function of the access road reaching to within a certain distance of all portions of the building's first floor exterior walls. This limit in NFPA 1 and the IFC is 150 feet for buildings without a complete sprinkler system. For fully sprinklered buildings, NFPA 1 permits this distance to be increased to 450 feet; the IFC leaves this decision up to the discretion of the code official. Further, NFPA 1 requires that the road extend to within 50 feet of an exterior door providing interior access. The distance from the building to a road or fire lane is sometimes referred to as “setback distance.” NFPA 1141 has additional guidelines for access locations versus building location, with variations depending upon building size, height, sprinkler protection, and separation from other buildings. Perimeter Access The options available for attacking a fire increase as more of a building's perimeter becomes accessible to fire apparatus (Figure 2.3). A concept, known as “frontage increase,” appears in the IBC and NFPA 5000. If a structure has more than a certain percentage of its perimeter accessible to fire apparatus, these codes allow the maximum size of the building to be increased. Ideally, the full perimeter would be accessible. During renovations, designers should use particular caution to ensure that the perimeter access continues to meet the NFPA requirements of fire and building codes. The original building site may have been based on a frontage increase. Changing the amount of perimeter access can result in noncompliant building size.  (Fig. 2.3) A combination of two public roads and two private fire lanes provides full perimeter access to this building. A single access route is a basic requirement in both NFPA 1 and the IFC. However, both codes allow the code official or AHJ to require additional access routes due to various factors that could inhibit access (such as terrain, climate, or vehicle congestion). NFPA 1141 requires two access routes for buildings over two stories or 30 feet in height. Multiple fire lanes should be as far removed from one another as practicable. Turnarounds Long, dead-end fire lanes or roads should provide a means for fire apparatus to turn around. Both NFPA 1 and the IFC require turnaround space for dead-ends that are more than 150 feet long. There are a number of configurations that facilitate turning maneuvers. These include, "T-turn," "Y-turn, " and round cul-de-sac style arrangements (Figures 2.4 and 2.5 for NFPA diagrams). NFPA 1141 requires a 120-foot turnaround at the end of dead-ends more than 300 feet long. Turnaround diagrams also can be found in Appendix D of the IFC.  (Fig. 2.4) Fire apparatus “Y-” and “T-turnarounds.” Reprinted with permission from NFPA 2003 Uniform Fire Reprinted with permission from NFPA 2003 Uniform Fire Code Handbook, © 2003, National Fire Protection Code Handbook, © 2003, National Fire Protection Association, Quincy, MA. Association, Quincy, MA.  (Fig. 2.5) Fire apparatus cul-de-sac turnaround. Reprinted with permission from NFPA 2003 Uniform Fire Reprinted with permission from NFPA 2003 Uniform Fire Code Handbook, © 2003, National Fire Protection Code Handbook, © 2003, National Fire Protection Association, Quincy, MA. Association, Quincy, MA. The basic clear width requirement for apparatus access in the IFC and NFPA 1 is 20 feet. NFPA 1141 calls for one-way fire lanes that are 16 feet wide; however, this applies to roads that do not abut buildings. A clear width of 20 feet will allow most aerial apparatus to extend the outriggers necessary to support the aerial ladder or elevating platform while in operation (Figures 1.2 and 2.1). However, some recently manufactured aerial apparatus require 24 feet of clear width for outrigger extension. Lanes wide enough for apparatus to pass one another will facilitate developing and expanding operations. NFPA 1141 contains a 24-foot clear width requirement for two-way fire lanes. Appendix D of the IBC calls for a 26-foot clear width at fire hydrant locations, extending for a distance of 20 feet in both directions, as well as a 26-foot width in the vicinity of buildings that are 30 feet or more in height (for aerial operations). NFPA 1141 also contains guidance on access in parking lots. Rolled or rounded curbs adjacent to properly designed sidewalks can effectively increase access width. These allow apparatus to easily negotiate curbs. Height The basic requirement for clear height of fire lanes in the IFC, NFPA 1 and NFPA 1141 is 13 feet 6 inches. Some modern aerial apparatus may require 14 feet of clearance. Potential for accumulation of snow and ice should be factored into height requirements. The NFPA 1 handbook recommends at least 14 feet in colder climates. Newer aerial apparatus may also require additional height. Finally, avoid overhead wires or other obstructions when determining fire lane locations. Building Proximity In areas with aerial apparatus that may respond to an emergency, the road or fire lane should be positioned at a distance from the building that will accommodate aerial ladder operation. Access too close or too far from the building will limit aerial ladder use. Where a fire lane is parallel to a building that is more than 30 feet high, Appendix D of the IFC calls for the near edge of the lane to be between 15 and 30 feet away from the building. Turn Radius The IFC and NFPA 1 leave turn radius requirements to the code official and AHJ. However, NFPA 1141 requires a minimum inside turn radius of 25 feet and a minimum outside radius for turns of 50 feet. The cul-de-sac depicted in Figure 2.5 shows an effective inside turn radius of 40 feet. Further, NFPA 1141 requires 2-foot curb cuts on either side of a fire lane where it connects to a road. Grade NFPA 1 sets a maximum grade (slope) of 5 percent for fire lanes. NFPA 1141 specifies a 10 percent maximum, as well as a 0.5 percent minimum to prevent pooling of water. However, some manufacturers have lower limits for specific apparatus. When aerial apparatus is set up for operation, the vehicle body must be leveled with the outriggers. The least grade possible would allow for the most rapid setup. Loads All access roads or lanes should be built to withstand the loads presented by modern, heavy fire apparatus as well as potential weather conditions. Paved surfaces, bridges, and other elevated surfaces (such as piers or boardwalks) should be designed to handle the weight of all apparatus that may use them. The IFC Appendix D has a load design requirement of 75,000 pounds. U.S. Department of Transportation standards dictate requirements for both load and frequency. The IFC references the Standard Specification for Highway Bridges from the American Association of State Highway Transportation Officials (AASHTO). Materials All-weather paved access is the best surface. Some jurisdictions permit the use of paver blocks or subsurface construction for fire lanes (Figure 2.6). These permit an area to be partially or fully landscaped, while being strong enough to allow fire apparatus to negotiate the area. However, these materials do have inherent limitations. Unless their perimeter is clearly marked, it is easy to drive off the edge. Also, in regions subject to snow accumulation, areas with paver blocks and subsurface construction cannot be plowed effectively (Figure 2.7).  (Fig. 2.6) Paver blocks were chosen instead of paving for this access road. The aesthetic benefits are minimal, and the road cannot be plowed effectively.  (Fig. 2.7) The same paver block access lane as shown in figure 2.6, but covered with snow. Access is blocked by a mound of snow plowed from the adjacent parking lot. Security concerns may impact fire service access. Gates (manual, electric, or radio controlled), bollards, pop-up barricades, and other perimeter controls can delay fire service operations. On the other hand, these access control measures can assist in keeping vehicular traffic away from fire lanes (Figures 2.8 through 2.10). During the design phase of a project, careful coordination between those responsible for security and fire protection can help resolve both concerns. In addition, proper gate size, location, and swing can facilitate fire service access. Wooden bollards are designed with cuts near their bases to allow access when apparatus bump them and break them. However, this results in delays while they are broken and cleared from the path of the apparatus, and may also cause damage.  (Fig. 2.8) Manual gates cause inherent delays because personnel must dismount to unlock them or cut through chains. However, they can also help keep the fire access lane clear by preventing vehicle parking.  (Fig. 2.9) The delays caused by electronic gates can be minimized by providing the fire department with access cards or remove access controls.  (Fig. 2.10) Pop-up barricades such as these are appearing more frequently due to security concerns. Unless security forces are constantly present to operate them, however, the fire department should be provided with a means to do so. Speed bumps or humps can impact fire apparatus access. Due to their suspension, these vehicles must come to a nearly complete stop to pass over these bumps, delaying arrival to a fire scene. Some special speed bump designs allow for fire apparatus to straddle bumps, while passenger vehicles cannot do so. Dips should also be avoided so that long wheel-base vehicles do not hit bottom and damage undercarriage components and overhanging equipment. Marking Fire lane signage is important, both for the public and enforcement officials (Figure 2.8). Examples include signs, curb painting, or curb stenciling. A jurisdiction's requirements must be followed exactly to ensure that no-parking provisions are legally enforceable. Speed bumps should be conspicuously painted, and signs indicating their location should be posted in climates subject to accumulation of snow and ice. Load limits should be posted conspicuously on both ends of bridges or elevated surfaces. [Table of Contents] PREMISES IDENTIFICATION The fire service must be able to rapidly identify and locate a specific building. Address numbers should be placed on the building facing the street or road on which the building is addressed. If the building entry faces a different street, both the street name and the number should be on the address sign. Numbers should be large enough to read from the street or road. If this is not possible due to the location of the building or due to obstructions, additional signs should be provided (Figure 2.11). The IFC specifies that address numbers be a minimum of 4 inches high. Some jurisdictions have a higher minimum height requirement, especially for commercial properties. The number should be in Arabic numerals rather than spelled out (for example, "120" instead of "One Hundred Twenty"). Buildings set back in groups that share common entrances can make quickly locating a specific building and the shortest route to it difficult. On such sites, additional signs with directional arrows and/or diagrams of the buildings and access layout should be posted (Figures 2.12 and 2.13). Whenever possible, signs should be illuminated. In areas subject to snow accumulation, signs should be positioned above anticipated accumulations. See the section Firefighter Access on page 21 for signage to assist the fire service in identifying portions of a building, or interior layouts.  (Fig. 2.11) Supplemental address sign at the entrance serving this building set far back from the road.  (Fig. 2.12) Directional address sign at the entrance of a property.  (Fig. 2.13) Diagrammatic sign showing an entire complex of buildings and their address(es). The addition of fire hydrant locations (and any other fire protection features) would assist responding firefighters. [Table of Contents] FIRE HYDRANTS Optimal positioning, spacing, location, and marking of fire hydrants can aid the fire service during emergency operations. Public fire hydrants are often under the purview of a local water authority, many of whom use American Water Works Association (AWWA) standards for fire flow and other criteria. The building design team is often responsible for hydrants and water supply systems on privately owned property sites. Both the IFC and NFPA 1 include appendices that give criteria for fire flow, and fire hydrant location and distribution. Other criteria can be found in NFPA 24, Standard for the Installation of Private Fire Service Mains and their Appurtenances. Features Typically, hydrants have a large suction hose connection (41/2 inches is a common size) called a “pumper outlet” or a “steamer” connection. Plus, they normally have two, 21/2 inch hose connections. Both wet-barrel type hydrants and the dry-barrel types used in areas subject to freezing have these features. Dry hydrants (those connected to a static source such as a tank, well, or pond) often have only a large connection or pumper outlet. Criteria for dry hydrants can be found in NFPA 1142, Standard for Water Supplies for Suburban and Rural Firefighting. Hose can be connected directly to a fire hydrant only if the connections match those needed by the area fire service. This includes type (threaded or quick-connect), thread style and size of connection. If the connections do not match, adapters (if available) will slow response. Position Optimal location and positioning of hydrants facilitates rapid connection of hose lines and devices. Considerations for designers include height, orientation, distance from the curb, and distance from surrounding obstructions (Figure 2.14). A clear distance is essential around the hydrant to enable a hydrant wrench to be swung 360 degrees (see Figure 2.16b) on any operating nut or cap nut. If the nearby obstruction is a plant or bush, consider its potential growth when planning for hydrant placement.  (Fig. 2.14) This hydrant should not have been located where it is likely to be blocked. Loading docks, by nature, will likely have vehicles parked. This is an example of building a potential deficiency into a facility. The truck could prevent use of the large pumper connection or cause the base to be kinked when used. Note the yellow bollards which protect the hydrant from vehicle collision.  (Fig. 2.15) Here is a pumper connected to a hydrant by its front-mounted suction hose. The pumper end of the hose has a swivel to facilitate reaching hydrants on either side.  (Fig. 2.16a) Pumper stopping to initiate a forward hose lay from a hydrant.  (Fig. 2.16b) The same pumper completing the straight lay towards the fire scene, and a firefighter preparing to operate the hydrant after the hose is safely layed out.  (Fig. 2.16c) Pumper performing a reverse hose lay from a fire scene (to feed the monitor nozzle shown) towards a hydrant. Maximum distance between hydrants differs greatly, depending on various local standards. IFC and NFPA 1 both include tables within appendices that enable a designer to find the required fire flow for any given building, and then select the corresponding hydrant spacing. Where apparatus may approach from different directions, hydrants should be placed primarily at intersections. If additional hydrants are needed to comply with local spacing requirements, they should be spaced along blocks at regular intervals. Location Pumpers may utilize hydrants in different ways. If the fire is close enough, a pumper can be positioned at a hydrant and use a large-diameter suction hose (Figure 2.15). Pumpers in urban and suburban areas with hydrants are generally equipped with large-diameter suction hoses connected to an intake on the pumper's front bumper, rear step, or side. This suction hose may be as short as 15 feet. In many urban areas, however, pumpers carry longer suction hoses in order to reach hydrants on the opposite side of a single line of parallel parked cars. If a fire is not close to a particular hydrant, a pumper may have to lay one or more hose lines between the hydrant and the fire. If a pumper lays a supply hose line from a hydrant towards the building with the fire emergency, this is called a “straight” or “forward” hose lay (Figures 2.16a and 2.16b). The opposite (laying supply hose from a building on fire to a hydrant farther down the street) is called a “reverse lay” (Figure 2.16c). Many fire departments use one or the other of these options as their standard procedure. Designers should take this into account when locating hydrants. For instance, hydrants at the end of dead-end streets will not facilitate straight hose lays. Hydrants that are too close to a particular building are less likely to be used due to potential fire exposure or collapse. Locating hydrants at least 40 feet away from protected buildings is recommended. If this is not possible, consider locations with blank walls, no windows or doors, and where structural collapse is unlikely (such as building corners). A rule of thumb for collapse zone size is twice the distance of the building's height. This is not a consideration in urban areas, where a multitude of hydrants are available for any given location. Marking A number of methods are used to enable firefighters to rapidly identify hydrant locations. The color used for hydrants should contrast as much as possible with the predominating surroundings. Some localities place reflective tape around the hydrant body. Other jurisdictions mount reflectors (usually blue) in the roadway in front of each hydrant; however, in cold weather climates these reflectors are often obstructed by snow. The best way to identify hydrants in areas subject to snowy weather is a locator pole which is visible above the highest expected snowfall. These are reflective or contrasting in color, and some have a flag, sign, or reflector mounted on top (Figure 2.17). These poles should be flexible enough to return to their upright position if someone tampers with them, or rigid enough to prevent this type of tampering. Some jurisdictions or sites go so far as mounting a light (usually red or blue) above the hydrants. A color coding system may indicate flow capability of hydrants. One such system is contained in NFPA 291, Recommended Practice for Fire Flow Testing and Marking of Hydrants. During construction or demolition, fire hydrants may be out of service. Designers should specify that inoperative hydrants be covered or marked during their projects, so that firefighters will not waste time attempting to use them.  (Fig. 2.17) One example of a hydrant locator pole with a reflective flag. [Table of Contents] FIREFIGHTER ACCESS Once firefighters have arrived and positioned their apparatus, they must go to work. Some factors affecting their efficiency include: the distance and terrain between the apparatus access and the building; how easily they can enter the building; the building's interior layout and vertical access (stairs/elevators/roof access); and, how quickly firefighters can locate fire protection features and utilities. The designer can make a positive impact in all of these areas. Site access Firefighters must hand carry all equipment beyond the point where apparatus access ends. Increased distance translates into additional time and effort to set up ladders, hose lines, and other equipment. If the area is easy to negotiate by foot, firefighters can move more quickly. The IFC and NFPA 1 contain requirements for access to building openings, such as approved walkways that lead from the apparatus access points to the entry doors. Fire department pumpers carry hose lines for attacking fires. These are usually smaller in diameter than the hose lines used to supply water to the pumper from a water source. Many pumpers have one or more hose loads of a fixed length connected into a pump discharge. These are “pre-connected” hose lines, often called simply “preconnects.” Firefighters deploy them rapidly for quick fire attack. However, their useful range is limited by their length, which is generally between 100 and 400 feet. Designers planning unusual designs for their buildings or working with unusual sites should coordinate with the local fire department regarding hose line access unless a standpipe system is provided in the building. Buildings under construction or renovation pose their own particular concerns to the fire service. Code provisions can be found in the IFC Chapter 14, IBC Chapter 33, NFPA 5000 Chapter 14, and NFPA 241. Designers should consider the accessibility of fire department connections, fire hydrants, and entry points. Some locations may be more likely to be obstructed by construction storage, truck unloading, cranes, phasing of the construction, and security fences. Designers should consider specifying these locations and the location of temporary and permanent fire protection equipment to avoid conflicts (Figures 5.14 and 5.15). Key Boxes and Entry Doors If firefighters need to conduct interior fire suppression operations, they must enter the building at one or more points. The fire service has an array of tools to force entry into buildings. However, forcing entry takes extra time and usually damages the building. Key boxes (also called “access boxes” or “lock boxes”) are small lockable vaults mounted outside building entrances (Figure 2.18). They are opened with a master key held by the fire department. Inside the box are the building's keys. Some jurisdictions require key boxes; others give building owners the option of installing them, or risking the need for firefighters to force entry into their buildings along with any resulting damage. Code officials enforcing the IFC and NFPA 1 may require key boxes. When key boxes are optional, designers may want to educate owners on their benefits.  (Fig. 2.18) Key box adjacent to fire command center. Theses boxes are often provided at main building entry doors. Note the fire department connection on the left.  (Fig. 2.19) Apartment locator. This door does not access apartments whose windows flack it.  (Fig. 2.20) Rear doors of a shopping center labeled for rapid access: utility room, fire protection equipment room, and individual tenant space. Interior Access Large, unusual, or complex buildings present a challenge to maneuvering and locating specific areas. Directional signs with room/tenant numbers, and graphic directories of tenant/agency layout can assist the public (Figure 2.21). The same diagrams may assist firefighters if they include: stairway and elevator identifiers, fire hose valve locations, fire alarm control panel location, fire alarm annunciator location, fire pump location and other fire protection features. Diagrams should also contain features to assist unfamiliar users with orientation, such as road names or a compass point. Detailed floor plans showing building layout and fire protection systems can assist the fire service. In buildings with fire command centers, a good location for these plans is in this command center. In other buildings, these plans may be locked inside the fire alarm annunciator panel.  (Fig. 2.21) Shopping complex diagram with views of the overall complex as well as the interior tenant diagram of the building in which the diagram is located. A routine function in any advanced fire suppression operation is to control (usually shut down) utilities. Making it easy to locate and identify utilities will speed firefighters' progress. Electric, gas, and other fuel controls should be located either in dedicated rooms with exterior marked entrances, or at exterior locations away from openings such as windows or doors (Figure 2.20). NFPA 170, Standard for Symbols for Use by the Fire Service, contains symbols for marking gas and electric shut-offs. Air handling equipment should also be prominently marked, especially if located out of sight. The fire service may need to quickly access rooms containing the following equipment: water service, control valves, fire pumps, electric service, switchgear, generators, fans and other mechanical equipment. Lettering for this signage should be at least six inches high with a 1/2 inch stroke (thickness of lines in each letter), unless the standard symbols are used. Marking of fire protection system devices within buildings is discussed further in the chapters on fire alarm systems, sprinkler systems, standpipe systems, and fire department connections. Elevators The use of elevators during fire incidents is very controversial. Elevators are not usually used for occupant evacuation. One exception is trained operators evacuating occupants with special needs. They should, however, be designed for fire service use. The elevator standard widely referenced in building and fire codes is ANSI A17.1, Safety Code for Elevators and Escalators. It details the two phases of emergency operation. Phase 1 of elevator emergency operation consists of a recall system that automatically sends elevators to a “designated” primary level. This occurs upon activation of a manual recall switch at the designated level or upon activation of smoke detectors in the elevator lobbies, hoistways, or machine rooms. If a detector is activated on the designated primary level, the elevator cars go to an alternate floor level. In either case, the elevators are rendered unavailable to building occupants. They remain at the recall level with doors open, so the fire service can quickly determine that they are clear of occupants and then use them in a manual control mode. The designated recall level usually is the ground or entry level. This will facilitate rapid fire department access. For buildings with entrances on multiple levels, designers should consult the fire department about the entrance firefighters intend to use initially. The fire department may also prefer to coordinate the designated recall level with the location of the fire alarm annunciator, fire control room, and/or the fire department connection. Phase 2 emergency operation permits the fire service to use the elevators under their manual control. Phase 2 operation overrides all automatic controls, including the Phase 1 recall. Solid-state elevator control equipment operates correctly only if maintained within a certain temperature range. NFPA 101, NFPA 5000, and the IBC require independent ventilation in machine rooms containing solid-state equipment that controls elevators traveling over certain distances. Whenever such elevators receive emergency power, their corresponding machine room ventilation would also receive emergency power. These features help maintain at least one elevator operational throughout fire suppression operations. Currently, ANSI A17.1 requires an automatic power shutdown feature for elevators that have fire sprinklers located in their machine rooms and, under certain conditions, in hoistways. Shutdown occurs upon or prior to the discharge of water, usually when heat detectors mounted next to each sprinkler head are activated. These heat detectors have both a lower temperature rating and a higher sensitivity (a lower response time index) than the sprinkler. However, to minimize the chance that firefighters will be trapped by a power shutdown, the temperature rating of the heat detector should be as high as feasible. Another shutdown method involves water flow detectors; however, these detectors cannot employ a time delay, so designers seldom choose this method. Note that in many cases NFPA 13, Standard for the Installation of Sprinkler Systems, permits sprinklers to be omitted from these areas. The National Fire Alarm Code, NFPA 72, requires that smoke detectors in either the elevator hoistway or the elevator machine rooms trigger separate and distinct visible annunciation at both the fire alarm control unit and the fire alarm annunciator. This alarm notifies firefighters that the elevators are no longer safe to use, and it also provides some warning time prior to the shutdown feature that is required with sprinkler protection. In addition, ANSI A17.1 requires a warning light in elevator cabs to flash when an elevator problem is imminent. Stairs NFPA 1, NFPA 101, NFPA 5000, the IBC, and the IFC all require that identification signage be provided inside stairwells at every level (Figure 2.22). These standards all require stairwell signs in buildings over a certain height, but the height thresholds vary. Signage should show the stair identifier, floor level, terminus of the top and bottom, roof accessibility, discharge level, and direction to exit discharge. On floors that require upward travel to reach the exit, a directional indicator should also be provided. It is important that these signs be located 5 feet above the floor and be visible with the stair door open or closed. In hotels or other buildings with room or suite numbers, the signs should also include the room or suite numbers most directly accessed by each stair on every level, (i.e., second floor of stairway 3 has direct access to rooms 202 through 256). The latter signage would be extremely important where certain stairways provide no access to some sections of the building.  (Fig. 2.22) Stairway ID sign. As stated above, the IFC, the IBC, NFPA 5000, and NFPA 241 contain special construction/demolition requirements. One stairway should be completed as construction advances. Conversely, as demolition progresses, one stairway should be maintained. These standards also address lighting and fire rating of the enclosure. Stair Capacity Building and fire codes typically require that stairs accommodate exiting occupants. Fire service personnel who may use the stairs are not factored into exit capacity calculations. In situations where occupants are still exiting and firefighters are using the same stairs to enter the building ("counter-flow"), the evacuation may take longer. Furthermore, in most cases, stairway capacity is designed based on the floor with the highest occupant load. Typically, stairs are not widened as one travels in the direction of egress unless the stairs converge from both above and below. This approach assumes that people will evacuate in a phased manner, beginning with the floor(s) closest to the fire origin. In an immediate general evacuation, or when people from other areas self-evacuate, the increased load will slow evacuation. Both of these bottlenecks will be made worse as the height of the building increases. Furthermore, total evacuation is becoming more commonplace due to concerns about terrorism. An effective solution to the counter-flow issue is a dedicated firefighting stairway. Codes in the United Kingdom contain specifications for such fire-fighting stairs, elevators, and intervening lobbies in buildings of a certain height (Figure 2.23). Current U.S. codes do not require dedicated stairways or elevators. The disadvantages of dedicated firefighting stairways include: cost, space, and the effort needed to keep them clear and in operating order. A solution to egress delays caused by either counter-flow or total evacuation is to provide additional exit capacity by means of additional stairs or widened stairs. Cost and space are also disadvantages of this solution.  (Fig. 2.23) Dedicated firefighting stairway/elevator tower. © Crown Copyright 2000 Queen's Printer of Acts of Parliament. [Table of Contents] HAZARDS TO THE FIRE SERVICE During a fire, any building may become inherently unsafe for occupants and fire service personnel. However, some building construction features present unique or unexpected hazards. This section discusses these hazards. Lightweight Construction Trusses are widely used in construction to span wide areas without the need for vertical supports, reducing both material and construction costs (Figure 2.24). Under ordinary conditions, trusses work well and building codes have permitted this type of construction for many years. However, trusses often fail suddenly and totally during fires. Both wood and metal trusses are made of interdependent members which all fail if one member fails. Adjacent trusses, in their weakened state, are then unable to carry the additional load and these also fail in quick succession. It is impossible for crews operating at a fire to predict the time or extent of a collapse since they cannot see how many trusses are affected, which components, and to what extent.  (Fig. 2.24) Building with wood truss construction. The adjacent finished building shows no indication from the exterior that wood trusses were used in its construction. Many firefighters have been killed in collapses attributed to trusses, particularly wooden ones, since the 1970s. Incident commanders and/or safety officers typically consider the presence of trusses in their fireground risk analysis. Marking these buildings that include trusses makes this information immediately available to firefighters. The State of New Jersey requires this as a direct result of five firefighters losing their lives in Hackensack in 1988 (Figure 2.25).  (Fig. 2.25) New Jersey truss building identification emblems. Wherever these lightweight construction techniques are used, serious consideration should be given to providing sprinkler protection throughout the building, if not already required. Sprinkler protection of combustible concealed spaces is an important feature for firefighter safety. Further discussion about lightweight construction can be found in “Building Construction for the Fire Service,” published by the NFPA. Shaftways Vertical shafts within buildings sometimes have exterior openings accessible to firefighters. Any such doors or windows should be marked "SHAFTWAY" on the exterior with at least 6 inch high lettering (Figure 2.26) as required by the IFC and NFPA 1. This warns firefighters that this would be an unsafe entry point. If properly marked, time will not be wasted attempting entry at these points.  (Fig. 2.26) Exterior shaftway marking. Skylights Without special precautions, roof-mounted skylights obscured by heavy smoke or snow may collapse under the weight of a firefighter. Skylights should be designed to bear the same weight load as the roof. The same applies to coverings over unused skylights. If this is not practical, mount barriers around skylights to prevent firefighters from inadvertently stepping on them. [Table of Contents] Chapter 3 Sprinkler Systems GENERAL Sprinkler systems provide early fire control or extinguishment, helping to mitigate the hazards for occupants and firefighters alike. Building codes, fire codes, and life safety codes specify when to provide sprinkler systems. These may be either locally written codes or adopted model codes such as the IBC, the IFC, NFPA 1, NFPA 101, or NFPA 5000. In addition, various sections of the OSHA standards require the installation of sprinkler systems. A widely accepted installation standard for commercial system design is NFPA 13, Standard for the Installation of Sprinkler Systems. Other standards include: NFPA 13D, Standard for the Installation of Sprinkler Systems in One- and Two-Family Dwellings and Mobile Homes; and NFPA 13R, Standard for the Installation of Sprinkler Systems in Residential Occupancies up to and Including Four Stories in Height. Designers may also refer to NFPA 13E, Recommended Practice for Fire Department Operations in Properties Protected by Sprinkler and Standpipe Systems, although any given fire service organization may follow different standard operating procedures. There is some flexibility in portions of the system that may impact the fire service. This chapter provides guidance to designers so they may exercise this flexibility to benefit fire department operations. Fire department connections for sprinkler systems are covered in Chapter 5. Standpipe systems (which are often integrated with sprinkler systems) are covered in Chapter 4. Sprinkler designers should also see Chapter 6 for additional guidance on fire alarm annunciation, and Chapter 7 for special coordination considerations about smoke control systems. [Table of Contents] ZONING It is important for sprinkler designers and fire alarm designers to work together, especially in unusual buildings. The fire alarm system will often have an annunciator to indicate the location of the alarm to the fire department. Sprinkler piping arrangement will limit options for fire alarm annunciation of water flow signals. Coordination is essential to furnish the fire service with clear information on the fire or its location. Sprinkler designers often think in terms of ceiling levels, since sprinkler piping and sprinkler heads usually are at ceilings or roof decks. However, alarm signals are reported in terms of their floor level to enable the fire department to respond to the correct floor during an emergency. Consider the situation of a building with two levels adjacent to a single level “high-bay” area. The first floor sprinkler zone should include both the high bay area and the lower level of the two-level section because each of these areas shares the same floor. Meanwhile, the upper level of the two-story section should have its own zone, even if the piping it contains is on the same level as the high bay area. In buildings with standpipe systems, sprinkler systems are usually combined with them and fed by a single water supply. Sprinkler systems are fed from the bulk feed mains or from vertical standpipe risers. NFPA 13 requires that sprinkler controls remain independent of standpipe systems. Typically, all sprinklers would be located downstream from a control valve that will not shut off any fire hose connections (Figure 3.1). This enables the fire department to shut off the sprinklers during the rare occasions when a sprinkler pipe fails, or the sprinklers are not controlling the fire. In this manner, hose connections remain available for manual fire suppression without losing pressure from the broken pipe, or the excessive number of activated sprinklers.  (Fig. 3.1) Sprinkler zone control station and zone indicator sign. In some cases, sprinkler systems are fed from two different standpipes or feed mains, in a “dualfeed” arrangement. Although this provides a hydraulic design advantage, NFPA 13 recommends against it to avoid confusion. If a designer chooses this arrangement (and the code official permits it), cross-reference signs should be provided at each valve. Each of these signs would indicate the location of the companion valve that feeds the same system. No single sprinkler system should be fed from three or more points, since the flow from a single sprinkler may not activate any of the flow switches. [Table of Contents] WATER SUPPLY CONTROL VALVES Fire service personnel often need rapid access to valves. If a valve is closed during an incident, it may need to be opened to permit flow of water. If a sprinkler valve is open, it may need to be closed to assist in manual suppression efforts. NFPA 13 requires marking for all water supply control valves including main valves, pump valves, sectional valves, and zone valves. The wording “control valve” by itself does not tell a user the specific use of the valve or what portion of the system is downstream of a particular valve. Using more descriptive labels such as “12th floor” or “pump bypass” will avoid confusion (Figure 3.1). If a valve identification is not obvious, an additional diagram should be provided. For instance, if a floor has multiple zones, each control valve sign should identify the corresponding zone, such as “12th floor east” or “zone 7-2.” A diagram of zones and the boundaries between them should be mounted adjacent to each valve (Figure 3.2). This will enable firefighters to quickly determine which valve controls each specific area.  (Fig. 3.2) Sprinkler zone diagram. When a water supply control valve must be located in a room or in a concealed space, a sign outside the door or access panel helps firefighters to quickly locate it (Figure 2.20). If the concealed space is above a suspended ceiling, the appropriate place for the sign is on the fixed ceiling grid, rather than on a removable ceiling tile. In addition, some jurisdictions require exterior signs that indicate the locations of interior valves (Figure 3.3).  (Fig. 3.3) Exterior sign showing valve location (in this case for a standpipe system). Valves for testing and draining purposes should also be labeled. This will prevent any potential confusion. Exterior valves should be placed in locations accessible even during a fire incident. Wall-mounted valves should be positioned no higher than 5 feet above grade (ground level) and located at least 40 feet from openings such as windows, doors, or vents (Figure 3.4). Post indicator valves should be at least 40 feet from the buildings they serve. The 40 foot distance is called for in NFPA 24.  (Fig. 3.4) Wall control valve next to window. Fire issuing from this window could prevent access to the valuve. [Table of Contents] FIRE PUMPS Fire pumps are used to boost the water pressure in sprinkler and standpipe systems and to deliver the required amount of water (Figure 3.5). This is necessary when the system is fed by a non-pressurized water tank, or when the water supply feeding the system has inadequate pressure. A fire pump may be driven by an electric motor, diesel engine, or steam turbine.  (Fig. 3.5) Fire pump. A fire pump controller is the enclosure that contains controls and status indicators for a fire pump. NFPA 20 requires these devices to be within sight of the fire pump motor or engine. The automatic transfer switch, which is often in a separate enclosure, transfers power to a secondary power source (when provided). Fire service personnel may need access to this equipment during the course of a fire. NFPA 20 contains reliability requirements for the power supply to an electrically driven fire pump. For example, power supply lines must be protected and the circuit must be independent of a building's electric service. The latter feature allows the fire service to shut down building power while the fire pump continues to run. 29 CFR Subpart S must also be followed. The most desirable location for a fire pump is in a separate building. This affords the most protection from fire, and gives firefighters easy access to the pump and its controllers. If locating the pump in a separate building is not possible, a fire-rated room with an outside entrance is the next best option. NFPA 20 requires pump rooms to be separated from the rest of the building by 2-hour fire-rated construction in buildings without full sprinkler protection, and 1-hour construction in fully sprinklered buildings. Inside and outside entrances to fire pump rooms should be labeled with signage. Minimum lettering size should be six inches high with a 1/2 inch stroke (thickness of lines in each letter). [Table of Contents] PARTIAL SPRINKLER SYSTEMS NFPA 13 requires installation of sprinklers throughout the building. However, in some situations the code or standard requiring sprinklers calls for protecting only a portion of the building. In these cases, exterior signage should indicate the portion of the building covered. A good location for this sign would be at the fire department connection (see the section Marking, page 47). Residential sprinkler systems installed under NFPA 13D and 13R primarily protect lives rather than property. Since property protection is secondary, large and significant areas may not have sprinkler protection (unsprinklered). One- and two-family houses protected by NFPA 13D systems are readily recognized as having this partial, life-safety type of protection. Apartments and condominiums with NFPA 13R systems may not be easy to identify. These systems are allowed in buildings four stories or less in height. However, some buildings that are considered four stories in height by building codes may still contain additional levels such as lofts, and basements which may be partially below grade. Several sides of these buildings may have six occupied levels above grade and still be considered four stories in height (Figure 3.6). The large unsprinklered areas can adversely impact firefighter safety and consequently the tactics employed. Fire department ground ladders may not reach the top occupied stories, and some apartment units may not be reached by the available access for aerial ladders. Exterior signage near the fire department connection can alert the fire department to this.  (Fig. 3.6) This building has six occupied levels from this view. However, it is classified as a four-story building by the code that was in effect during its construction. As such, an NFPA 13R residential sprinkler system (with no sprinklers in the combustible attic or in the floor/ceiling assemblies) protects it. Chapter 4 Standpipe Systems GENERAL Standpipe systems consist of a fixed piping system and hose valve connections to preclude the need for long hose lays within tall or large buildings. Water is fed into these systems either through an automatic water supply or manually through a fire department connection. The system delivers water to hose connections throughout the building, usually in enclosed or exterior stairs (Figure 4.1). Firefighters then extend hose lines from these hose connections to conduct interior fire suppression operations. Standpipes are, in effect, a critical component in the supply of water to interior firefighting crews. Deficiencies can have disastrous consequences, such the loss of three firefighters in the 1991 Meridian Plaza fire in Philadelphia.  (Fig. 4.1) A dry standpipe in an exterior stair. The FDC inlet is to the right of the building entrance, the riser pipe extends through the left side stair landings, and hose connections are at each level, including the roof. Building and fire codes specify when designers should incorporate standpipe systems. This can be a locally written code or an adopted model code such as the IBC, the IFC, NFPA 5000, or NFPA 101. Standpipe systems requirements are based on building height or interior travel distances. In addition, standards such as those issued by OSHA require standpipe systems in certain situations. The IBC and IFC include water supply requirements and some design details. The complete installation standard for standpipe systems is NFPA 14, Standard for the Installation of Standpipe and Hose Systems. This standard allows options for hose connections, valving, and other design features. This chapter illustrates ways that designers can implement various options in different situations to assist the fire service. The considerations in the section, Water Supply Control Valves, on page 29, regarding valves also apply to standpipe systems. Fire department connections are covered in Chapter 5 on page 41. [Table of Contents] FIRE HOSE CONNECTIONS Hose connections in Class I systems are typically 21/2 inch threaded outlets. As discussed in the Fire Hydrant section, it is essential that hose connection type and size match that used by the fire department in the jurisdiction where the building is located. The primary location for hose connections is within enclosed, fire-resistance rated stairs. Firefighters set up and begin their attack from within the protected stair enclosure. Then the attack may proceed towards the fire location. If a quick evacuation becomes necessary, the hose then functions as a lifeline, leading the firefighters back to the protection of the stairs. The current preferred location for stairway hose connections is at the intermediate stair landings between floors (Figure 4.2). This is because firefighters usually stretch hose from below the fire floor for their protection. If the connections are at intermediate landings, the hose line reaches farther than it would if the connection were at the main landing, a full story below the fire floor. However, both NFPA 14 and the IBC permit connections to be located at main floor landings, if so desired by a given jurisdiction.  (Fig. 4.2) Hose connection on intermediate landing as viewed from the main landing where the stair entry door is located. Fire attack using hose lines from stairway hose connections requires stair doors to be propped open (Figure 4.3). This prevents the hose from becoming kinked and restricting water flow; however, it can also allow smoke and heat to enter the stairway. At this point, occupants should either have exited the building, be below the level of the fire, use another stairway, or be sheltered in place until after the incident. But, there is now some concern within the fire protection community that occupants may be exposed to fire or smoke conditions during these firefighting operations. Some reasons for this include: conflicting evacuation instructions, occupants not following evacuation instructions, the need for the fire department to operate from all stairways, or the need for total building evacuation (especially in response to terrorist incidents).  (Fig. 4.3) Training session showing a firefighter chocking open a stair door to initiate a fire attack from a stairway hose connection.  (Fig. 4.4) Hose connection on the corridor side of the stair door.  (Fig. 4.5) Exterior view of open air vestibules between the stair and the interior of a building. Remote hose connections outside of stairwells can often be hard to locate. They should be placed as uniformly as possible on all floors to make them easier to find. Highly visible signs or other markings can assist firefighters in locating them quickly (Figures 4.6 and 4.9). Often these may be tailored to décor or occupancy to satisfy architects or interior designers (Figures 4.7 and 4.8). NFPA 170, Standard for Symbols for Use by the Fire Service, contains symbols for marking standpipe outlets (hose connections).  (Fig. 4.6) Stripe on column to identify hose connection location in parking garage.  (Fig. 4.7) Sign to identify hose connection location in an exhibit hall.  (Fig. 4.8) Sign to identify hose connection location in a shopping mall.  (Fig. 4.9) Bollards and striping to create an access path in a parking garage. Bright signs at the top of column help to locate the valve. [Table of Contents] DESIGN PRESSURE Most new standpipe systems are designed by hydraulic calculations. This ensures that the water supply, pipe sizes used, and pumps (if needed) will provide a certain flow and pressure at a specified number of hose connections in the system. The current NFPA 14 specifies a minimum design pressure for Class I systems of 100 pounds per square inch (psi) at a specific flow rate, which depends on the number of hose connections per floor. However, it includes an exception that allows design pressures as low as 65 psi, if this will accommodate the fire suppression tactics. These minimum pressures are based on certain assumptions about the fire department equipment and tactics, as well as the fixed fire pump feeding the standpipe system. The designer should compensate if the equipment or tactics vary from these assumptions in a particular building or jurisdiction. This will ensure the adequacy of fire streams to assure the safety of firefighters conducting interior operations. A straight stream nozzle requires at least 50 psi to operate. With the friction loss in fire hose added, 65 psi at the hose connection will provide 50 psi to a straight stream nozzle with 250 gallons per minute (gpm) flowing through 100 feet of 21/2 inch fire hose. The same pressures can deliver 95 gpm through 100 feet of 13/4 inch hose. In 1993, NFPA 14 changed the minimum required design pressure from 65 psi to 100 psi at the hose connections. At the same time, this standard was revised to permit longer distances between hose connections and remote areas of a building. Currently, this distance can be up to 150 feet for buildings without complete sprinkler protection, and up to 200 feet for fully sprinklered buildings. The 100 psi design pressure will permit greater flows or longer hose lines, but only with the same straight stream nozzles. Many fire service organizations begin their attacks with fog or combination nozzles that generally require at least 100 psi to operate. This dramatically increases the pressure requirements at the hose connection. If 100 psi is actually available at the connection, every combination of hose size and length will result in inadequate nozzle pressure. It is assumed that firefighters will use fog or combination nozzles early in a fire situation, when only one or two hose lines are in operation. It is further assumed that the total flow will be less than the rated flow of the pump. At these lower flows, output pressures will be higher. Finally, it is assumed that if the fire grows, either straight stream nozzles will be utilized or the pumpers supplying the fire department connections will provide greater pressures. Designers must be aware of this information for a number of reasons. First, designers should only use |