AUTHOR: Shawn Mahoney

Fire Alarm Pull Station Installation Height

Are you in the field installing a fire alarm system and need to know what the required fire alarm pull station height is? Or maybe you are working on a fire alarm design detail and want to know what the required height is for your fire alarm call point. You’re not the first one to ask this question, so I will get right into it. What is the required height for a fire alarm pull station? The simple answer that the operable part of the pull station needs to be at least 42 in. (1.07 m), and not more than 48 in. (1.22 m), above the finished floor. Additionally, one pull station needs to be within 5 ft (1.5 m) of each exit doorway on each floor where required to be installed in a building. Both of these requirements are shown below. The code requirements NFPA 72®, National Fire Alarm and Signaling Code®, refers to a fire alarm pull station as a manually actuated alarm-initiating device, and defines it as a manually operated device used to initiate a fire alarm signal. Other publications may refer to a fire alarm pull station as a manual fire alarm station, pull station, fire box, call point, and so on. The requirements for the installation height can be found in Section 17.15 of the 2022 edition of NFPA 72. If you want to learn how you can easily find those requirements in the code using NFPA LiNK®, take a look at the video below.     It’s important to note that NFPA 72 does not require that manual initiating devices be installed in buildings. Instead, it provides the installation requirements when the devices are required by other codes such as NFPA 101®, Life Safety Code®, NFPA 1, Fire Code, or NFPA 5000®, Building Construction and Safety Code®. Mounting the back box When mounting the back box for a manual pull station it is important to know the make and model of device that will ultimately be installed. As you saw above, the measurements are taken to the operable part of the device, not the middle of the device. Additionally, these measurements are taken from the finished floor, so when installing back boxes prior to the installation of the flooring, the thickness of the flooring must be accounted for in the measurement. Tolerances NFPA 72 allows a tolerance for the installation of devices. This tolerance is noted in 1.6.5 and A.1.6.5. Where dimensions are expressed in inches, it is intended that the precision of the measurement be 1 in., which would be plus or minus 1⁄2 in. The conversion and presentation of dimensions in millimeters would then have a precision of 25 mm, which would be plus or minus 13 mm. Therefore, the maximum height of the operable portion of the manually actuated alarm-initiating device could be up to 48.5 in. (1.233 m) if you account for the allowable tolerances in NFPA 72. Other wall-mounted appliance and device heights Do you want to learn more about installation heights for other fire alarm devices, appliances, and equipment? The video referenced earlier in this blog outlines how you can use the direct navigation feature of NFPA LiNK (NFPA DiRECT®) to find the mounting heights not only for fire alarm pull stations, but also for other wall-mounted fire alarm equipment, as well as all of the supporting code requirements.  

How To Maintain Building and Equipment Access for the Responding Fire Department

When facility managers and building owners think of fire department access, they typically think about keeping a fire lane clear, so the responding fire department has a place to set up their equipment in case of an emergency. While this is critical to an effective response, there are many other aspects of a building that need to be properly maintained to provide appropriate fire department access to the building, as well as crucial fire and life safety equipment.  Building Identification To assist emergency responders in locating properties, building address numbers must be visible from the street. Premises or building identification is covered in Section 10.11 of NFPA 1, Fire Code. Address numbers can be mounted either on the building itself or, if the building is not visible from the street, on a post located on the street. The numbers should be designed to contrast the background of the building or post and be large enough to be easily seen from the street. Fire Apparatus Access Road To provide effective manual fire suppression operations, the fire department must be able to gain reasonable access to a building. Chapter 18 of NFPA 1 provides requirements for fire apparatus access. According to the Fire Code, access roads must be provided and maintained to allow the fire apparatus to be able to get within 50 ft (15 m) of at least one exterior door and to be within at least 150 ft (46m) of all exterior portions of the first story—this is increased to 450 ft (137 m) if the building is sprinklered. These access roads should be kept unobstructed to a width of not less than 20 ft (6.1 m) and a height of not less than 13 ft 6 in. (4.1 m). Keep in mind that these widths and heights may be altered by the local authority having jurisdiction (AHJ) to accommodate responding apparatus. It is also important to maintain the proper turning radius needed for the responding apparatus and ensure that any required turnaround space is also kept clear. If the access road has a dead end that is greater than 150 ft (46m), a turnaround space is required. To ensure that your fire apparatus access roads are unobstructed from any parked vehicles or other obstructions, it may be a good idea to provide signs or roadway markings. This is something that may also be required by the AHJ. Access Boxes The fire department must be able to open any doors leading into the building that may be locked. This means an access box may be required by the AHJ to give the fire department the ability to obtain keys to unlock the building during an emergency. Typically, these access boxes are located near the front entrance of the building. If these access boxes are not provided, it is likely that the first responders may need to perform some forcible entry to gain access to the building, which means doors may be damaged or destroyed. If access to the premises is secured by a locked gate, then the fire department must be provided with an approved device or system to unlock the gate. This could be done with the installation of an access box on or near the gate that contains keys to the gate, or the responding fire department can be provided with an access card or other security device. Fire Hydrants The fire department also needs access to water. This is typically done by connecting to fire hydrants located on or near the property. All fire hydrants should be maintained so that a clear space of not less than 36 in. (914 mm) is provided all the way around the hydrant. Additionally, a clear space of 60 in. (1524 mm) needs to be provided in the front of a hydrant if it has a connection that is greater than 2 1⁄2 in. (64 mm). This clear space is provided to allow the connection and routing of hose lines. If you live in a cold climate, this means that all snow must be removed from around the hydrant after each storm. Fire Department Connection Your building may also have a fire department connection. This is a hose connection or series of hose connections located on the exterior of the building that connect either to a standpipe system or to the sprinkler system. Connections to standpipe systems allow the fire department to pressurize the standpipe system in the building so they can connect their hose lines to pre-installed hose connections within the building to fight the fire. Connections to the sprinkler system allow the fire department to pump additional water into the sprinkler system increasing the amount of available water and pressure within the system to control the fire. If your building has a fire department connection it is important to maintain proper access, which is outlined in Chapter 13 of NFPA 1. Most importantly, the code requires that a minimum of 36 in. (915 mm) of clear space be maintained to ensure the fire department can not only see the fire department connections but can also make use of them. This includes making sure any tree branches or vegetation are cut back and no other obstructions, such as trash cans, are present. Fire Alarm Control Unit If your building has a fire alarm and signaling system, it is important that the fire alarm control unit (FACU)—also known as the fire alarm panel—is accessible. The FACU allows the fire department to identify which initiating devices are in alarm to help them better locate the fire. If the fire alarm system also contains an emergency voice communication system, then the fire department can also use the system to communicate with occupants in the building to give them direction. Typically, the fire alarm control unit is going to be located near a main entrance in an area such as the lobby. It is also possible that the fire alarm control unit is in a different place and a fire alarm annunciator is placed near the main entrance. This fire alarm annunciator is connected to the fire alarm control unit and allows the first responders to see all of the displays on the fire alarm control unit from a remote location. Both the fire alarm control unit and any fire alarm annunciators must be free of any obstructions and must be visible at all times. If either the fire alarm control unit or the annunciator is locked, it is important to provide the fire department with keys so they can operate the system. Emergency Command Center If your building is a high-rise, meaning that it’s a building where the floor of an occupiable story is greater than 75 ft (23 m) above the lowest level of fire department vehicle access, then it is likely that your building has an emergency command center or a fire command center. This is a space that is separated from the remainder of the building with fire resistance–rated construction and provides a space for the fire department to set up their command if there is an emergency or fire in the building. The emergency command center may contain the following: ·      The fire department communication unit ·      A telephone for fire department use ·      Schematic building plans detailing the floor plan, means of egress, fire protection systems, firefighting equipment, and fire department access ·      A work table ·      The fire alarm control unit (fire alarm panel) or annunciator ·      Elevator location indicators ·      Emergency and standby power indicators ·      Fire pump status indicators ·      Smoke control system controls Typically, these rooms are located near the main entrance of the building or off the main lobby. It is crucial that these spaces remain accessible and are free from all storage or obstructions.  Fire Pump Room A fire pump may be required in your building to provide the required water pressure for a standpipe system or an automatic sprinkler system. Fire pumps are required to be in a room that is separated from the remainder of the building with fire resistance­–rated construction. If your building has a fire pump room, it is important that this room be properly identified and free of all storage and equipment that is not essential to the operation of the fire pump. Fire pump rooms are required to be accessed from a protected interior pathway or from an exterior door, so it is also important to ensure that the protected interior pathway or the path to the exterior door of the pump room is also free and clear of obstructions. Summary As you can see, there are many more aspects to fire department access than just keeping a fire lane clear. We want to make sure that the fire department and first responders can properly identify the building as well as access all of the building equipment that they may need during their response. It is important to get into a habit of regularly checking these items as you never know when you might need the fire department or first responders at your building, and in the case of an emergency, every second counts. Interested in learning more? Take a look at this video excerpt (below) from our Fire and Life Safety Operator Online Training, which goes over items that need to be maintained to assist the fire department.

Backflow Preventer Types

When a fire protection system (non-potable water system) is connected to the public water supply, the systems are said to be cross connected. In some localities, cross connections may be prohibited or closely regulated by health authorities.  Improperly protected water systems have the potential to lead to illness and even in some cases death. Federal regulations require states to provide quality water when it is intended for public consumption. Because of this, states and municipal governments have taken various steps to protect the potable water supply, such as requiring backflow prevention when the fire protection system will be supplied by a potable water source. Backflow preventers are installed to prevent contaminants from traveling from the non-potable source to the potable public drinking supply via back siphonage and back pressure.  Back siphonage is backflow caused by a negative pressure in the supply piping. This negative pressure in the supply piping is similar to drinking water through a straw. The water from the non-potable system is pulled into the supply piping. Backpressure is backflow caused by a pressure in the non-potable water system being greater than the pressure in the potable water supply piping. This higher pressure causes water in the non-potable system to be pushed back into the supply piping.  Its important to note here that the requirement for backflow prevention in a fire protection system comes from the local water authority and not from any NFPA standard. For example, NFPA 13 does not require a backflow preventer for an automatic sprinkler system, however, if one is required, it provides additional requirements to ensure it is installed in a manner that limits its impact on system operation and provides for a means to test the system.  There are a few different types of backflow preventers available, and the type of backflow preventer required by the water authority is going to be based on the degree of hazard posed by the cross connection. The degree of hazard may be classified differently, but the two main degrees include high hazard and low hazard. A high hazard is a system that could introduce waterborne disease organisms, or harmful chemical, physical, or radioactive substances into a public water system, and which presents an unreasonable risk to health. An example of this may be a system that contains an additive, such as a fire protection system with antifreeze, or a foam system. A low hazard is a system that could cause aesthetic problems or have a detrimental secondary effect on the quality of the public potable water supply, an example of this could be a fire sprinkler system that contains stagnant water or contains microbiologically influenced corrosion (MIC). The Double Check Valve Assembly (DCVA) and the Reduced Pressure Zone Assembly (RPZA) are the most used backflow preventers for fire protection systems, but I will discuss all the most common backflow preventers used in plumbing systems. An air gap is the most effective type of backflow prevention. This method utilizes a physical air space between the potable and non-potable systems. The most common example of this would be a faucet and a sink. This may be a backflow prevention method used to fill a water supply tank. Air gaps can be used to protect low and high hazards under both back siphonage and backpressure. An Atmospheric Vacuum Breaker Assembly contains an air inlet valve and a check seat. When water flows through, the air inlet valve closes, but when the water flow stops, the air inlet valve falls against the check seat and stops back siphonage, while at the same time letting air into the system. AVBs can only protect against a low or high hazard under back siphonage. The Pressure Vacuum Breaker Assembly is like an atmospheric vacuum breaker, but it contains a spring-loaded air inlet valve and check valve, two shutoffs, and two test cocks. When water is flowing, the check valve is open and air inlet valve is shut, when water stops flowing, the check valve shuts, and air inlet valve opens. The addition of the shutoff valves and test ports allows for this assembly to be field tested. The PVB only protects against low or high hazards under back siphonage. A Double Check Valve Assembly (DCVA) contains two spring-loaded check valves with two shut off valves and four test cocks. In the event of a backflow the first check valve will close, if that check valve fails then the other check valve will close. The addition of the shutoff valves and test ports allow this assembly to be tested. A DCVA can be used to protect against low hazards under both back siphonage and back pressure.   A double check valve detector assembly is the same as a DCVA, but it also includes a bypass for the installation of a water meter to monitor for incidental water use that is also protected with a smaller DCVA.   A Reduced Pressure Zone Assembly (RPZA) provides the maximum protection and along with the DCVA is the most common type of backflow prevention used in fire protection systems. This assembly contains two spring-loaded check valves with a differential relief valve between them and two shut off valves and four test cocks. The RPZA operates like a DCVA with the addition of a relief valve, if there is a backflow the check valves will close, and the relief valve will open, resulting in a reduced pressure zone and air gap between the check valves. The two shut off valves and four test cocks allow this assembly to be field tested as well. The RPZA can be used to protect high and low hazards under both back siphonage and back pressure.    A reduced pressure zone detector assembly is the same as a RPZA, but it includes a bypass for the installation of a water meter to monitor for incidental water use that is also protected with a smaller RPZA. As you can see, there are a few different types of backflow preventers, and the selection of the right preventer is going to depend on the requirements from the local water authority as well as the hazard. When the design of a fire protection system includes a backflow preventor, the designer must make sure that they account for the backflows impact on the available water supply pressure. If a backflow preventor is installed on a fire protection system, it is also important that proper inspection testing and maintenance (ITM) be performed (such as a forward flow test) to ensure that the backflow remains operational and does not seize up, which could impair the fire protection system.

Fire Alarm Notification Delay from Sprinkler Waterflow

Over the past several months, I have noticed a few incidents occurring in mercantile occupancies that have raised some questions related to the allowable delay between sprinkler activation and fire alarm notification in the event of a fire, which is governed by NFPA 72®, National Fire Alarm and Signaling Code®. One example is a video of this fire in a Maryland Walmart. The video was taken by an occupant inside the building as they are exiting the building and shows sprinklers operating and controlling the fire. You notice that there is a time delay between the activation of the sprinklers and the activation of the occupant notification within the building. Many people are asking the question, why doesn’t the fire alarm immediately warn the occupants that there is a fire in the building as soon as the sprinklers activate? The answer is that NFPA 72 permits up to a 100-second delay between sprinkler waterflow and occupant notification, as you can see at the end of the video, the fire alarm did activate the occupant notification via audible and visual notification. The allowance for a 100-second delay before the actuation of alarm notification appliances is broken down into two requirements. The first requirement is related to the waterflow initiating device and found in section 17.13 of the 2022 edition of NFPA 72. 17.13.2 requires that the waterflow initiating device activate within 90 seconds after a flow occurs that is equal to or greater than the flow from a single sprinkler of the smallest orifice size. The 90-second allowance exists to reduce the number of nuisance alarms caused by water flow that can occur from pressure surges in the water supply system and allows time for the flow from a sprinkler in the system to be detected at the riser. The delay provides added assurance that the water flow in the sprinkler piping is in fact sustained flow from a sprinkler, and not just the result in a change in pressure. The reduction of nuisance alarms is important because a fire alarm system that has many nuisance alarms can cause the occupants to become complacent and may begin to ignore the fire alarm. This delay in the water flow switch activation can be created within the flow switch itself using a retard dial, or it can be accomplished with the use of a retarding device such as a retard chamber when using a pressure switch that is connected to the alarm port on a sprinkler system alarm valve. The second part of this delay is found within section 10.11.1. This section requires that the actuation of alarm notification appliances at the protected premises occurs within 10 seconds after the activation of the initiating device. This requirement exists to ensure that the operation of the notification appliances occurs within a timely manner after a fire has been detected. Between those two requirements in section 17.13.2 and 10.11.1, NFPA 72 permits up to a 100-second delay between the initial waterflow from a sprinkler and the actuation of the notification appliances within the building. In addition to this allowance intended to reduce the number of nuisance alarms, allowances exist to delay the actuation of notification appliances for other initiating devices with the use of a presignal feature or positive alarm sequence, though both require a detailed response plan and approval from the authority having jurisdiction. The next time someone asks you a question about the timing of sprinkler waterflow and fire alarm notification, remember that NFPA 72 permits the delay in the actuation of fire alarm notification appliances. This timing is engineered into the operation of the systems, and it exists to ensure that they function as effectively as possible and reduce unwanted nuisance alarms.

Atrium Design Considerations

The use of vertical openings within buildings is a common design feature. Large spaces, typically in the center of a building, created by vertical openings through floors and ceilings are commonly referred to by architects as an atrium. Atriums are desirable to some building designs because they allow for light and ventilation within a space and allow for many parts of a building to feel connected with each other. However, atriums and other vertical openings pose some unique fire protection and life safety hazards that must be considered such as limiting the spread of fire and the products of combustion throughout the building. The base requirement in NFPA 101, The Life Safety Code, states that every floor that separates stories of a building must be constructed as a smoke barrier. If there are openings in the floor, these openings must be enclosed with fire barrier walls that extend from floor to floor or floor to roof. These two main base requirements apply to all occupancies unless a specific occupancy chapter provides an alternative option. This base requirement of separating stories exists to minimize the number of occupants that are exposed to the effects of a fire. There are exceptions that permit unprotected openings within floors that separate stories. The following protection packages are outlined in NFPA 101 and are permitted to be used under certain conditions: communicating space atrium partially enclosed two-story opening convenience opening When selecting an unprotected vertical opening protection package, the first thing to consider is the number of stories that are open to each other. If the opening connects three stories or fewer, then you will need to look and see if you can meet the requirements of a communicating space or convenience stair opening, if the opening connects 4 stories, then the space will need to meet the requirements for an atrium or convenience stair. If more than 4 stories are connected, then the requirements for an atrium will need to be met. For a deeper dive into types of vertical openings take a look at this blog. Let’s assume that the vertical openings within the building need to be protected as an atrium. Section 8.6.7 of NFPA 101 provides the requirements for an atrium, which include: an engineering analysis for smoke layer development separation from other spaces exit access requirements permissible contents sprinkler protection and if provided, requirements for a smoke control system (smoke management system) In this blog I am going to focus on the engineering analysis for smoke layer development and separation requirements. Where atriums are used, there is a need to minimize the risk of occupants on other floors being exposed to untenable conditions, such as low visibility, heat, and dangerous concentrations of smoke and toxic gases. To ensure that occupants are afforded tenable conditions, an engineering analysis must be completed to confirm that the smoke layer will stay at least 6 ft (1830 mm) above the highest walking surface within the atrium space for a period that is equal to 1.5 times the calculated egress time, or 20 minutes, whichever is greater.  It should be noted that the requirement for an engineering analysis does not mean that a smoke control or smoke management system is required in all atriums because there are cases in which tenable conditions can be maintained without a smoke management system. The engineering analysis should include the following elements: Fire dynamics, including the following: Fire size and location Materials likely to be burning Fire plume geometry Fire plume or smoke layer impact on means of egress Tenability conditions during the period of occupant egress Response and performance of building systems, including passive barriers, automatic detection and extinguishing, and smoke control Response time required for building occupants to reach building exits, including any time required to exit through the atrium as permitted in NFPA 101. If the engineering analysis shows that a smoke control system (smoke management system) is required in the atrium to keep the smoke layer at least 6 ft (1830 mm) above the highest walking surface then the system will need to be designed and installed in accordance with NFPA 92, Standard for Smoke Control Systems. NFPA 92 allows for different design approaches to smoke management including natural smoke filling, mechanical smoke exhaust, gravity smoke venting, and opposed flow to prevent smoke movement. For more information on smoke control systems take a look at this blog. To protect the occupants in adjacent portions of the building, NFPA 101 requires that atriums be separated from adjacent spaces using one of the following methods: Fire barriers with not less than a 1-hour fire resistance rating. Any number of levels are permitted to be open directly to the atrium based on the results of the engineering analysis. Glass walls and inoperable windows can serve as the separation provided they are protected with closely spaced sprinklers on either side of the glass. Want to learn more about atrium design? Want to see all the referenced requirements within the codes and standards? Take a look at our atrium design situation in the DiRECT feature on NFPA LiNK. This situation goes into more detail on design requirements as well as sprinkler system and fire alarm system design considerations. For more information on how to access NFPA LiNK with a 14-day free trial on your computer or mobile device go here.
Fire Hydrant

Calculating the Required Fire Flow

Providing water to the responding fire department is a crucial aspect of the overall fire protection and life safety strategy of an entire community. When a new building is developed or an existing building is renovated, it is important to make sure that the proper amount of water is available to the responding fire department to allow for both suppression of the fire in the building, and protection of any exposed buildings. Because of this, NFPA 1, The Fire Code, requires a minimum amount of water be provided based on the type of construction of the building as well as fire flow area. Fire flow is defined as the flow rate of a water supply, measured at 20 psi (137.9 kPa) residual pressure, that is available for the responding fire department for manual firefighting, typically this is water that is available at the surrounding fire hydrants, but it can be supplied with another approved source such as a static water supply like a tank or pond, or even using a fire department tanker shuttle service. In addition to using the required fire flow water supply for manual suppression of the fire with hose lines, when responding to a fire at a sprinklered building or a building that contains a standpipe system, the fire department will also connect their pumper up to these systems through a fire department connection to use their pumper and the available fire flow water supply to supplement the water supply of these systems. There is a difference between the required fire flow in NFPA 1 and the hose stream allowance that is required in NFPA 13, Standard for the Installation of Sprinkler Systems, to be added to the required sprinkler demand. The fire flow required by NFPA 1 is being provided for the fire department for both protection of exposures as well as the water required for manual suppression, while the hose stream allowance in NFPA 13 that is added to a sprinkler system demand is adding a safety factor to the calculations to account for the fact that the fire department will likely also be using water from the same water supply that the sprinkler system is being fed from, which will reduce the available water. Because they are separate requirements that are trying to accomplish different goals, the fire flow, per NFPA 1, is not required to be added to the demand of an automatic sprinkler system in sprinklered buildings. However, the available water supply must be the greater of the two, either the sprinkler system demand, or the required fire flow. If the available water supply can support the greatest demand, it will also be able to support the other demand as well. NFPA 1, provides requirements for fire flow in Section 18.4. The requirements are performance-based, which means they do not specify the type of system necessary to provide the required fire flow. The AHJ (typically the responding fire department) has the final authority to determine if the proposed water supply delivery method is appropriate. Fire flow is calculated based on the fire flow area of the building. The flow area is the total floor area of all floor levels of a building, except for Type I (443), Type I (332), and Type II (222), in which case the fire flow area is the largest three successive floors. The fire flow area should be determined based on the area between the surrounding exterior walls of each floor and the fire separation walls used to create separate buildings.   Table lists the minimum required fire flow and flow duration for buildings based on fire flow area and construction type. For more information on construction types, take a look at this blog.  For example, a Type I (443) building with a fire area in the range of 0-22,700 ft2 (0-2108.83 m2) is required to provide the fire department with a fire flow of 1500 gpm (5677.5 L/min) for a flow duration of 2 hours (see below). Enlarge image Paragraph states that the required fire flow for buildings other than one and two family dwellings can be reduced by 75 percent when the building is protected by an approved automatic sprinkler system. However, the resulting fire flow cannot be less than 1000 gpm (3785 L/min) or 600 gpm (2270 L/min) where quick response sprinklers are used throughout. Sprinklered one- and two -family dwellings fire flows can be reduced by 75 percent with no minimum and the duration decreased to one hour. Here is an example video stepping through the calculation of the required fire flow taken from our Certified Fire Plans Examiner Learning Path. As mentioned, hydrants are the primary method for providing a fire flow. NFPA 1 requires that the flow capacity of all fire hydrants within 1000 ft (305 m) of a building not be less than the required fire flow. The distance should be measured as the fire apparatus would lay hose out on the fire department access road to the building. The distance should not be measured across adjacent lots or through fences, gates, or other obstructions that would prevent the normal movement of a fire apparatus performing a hose lay to a fire hydrant. Table of NFPA 1 specifies the maximum capacity that each hydrant can be credited for when calculating the total available fire flow, based on the distance of the hydrant from the building. Enlarge Image Fire Hydrants must be installed to meet the requirements of NFPA 1, waterworks standards, and any local requirements of the jurisdiction. Where required by the Authority Having Jurisdiction (AHJ), the hydrant needs to be provided with a reflector and proximity flag. In some jurisdictions, the hydrants are also color-coded to indicate the available flow rate. Fire hydrants need to be located within 600 feet (183 m) from the closest point of the building in detached one- and two-family dwellings, with a maximum spacing of 800 feet (244 m). For buildings other than one- and two-family dwelling, hydrants need to be within 400 feet (122 m) of the building with a maximum spacing of 500 feet (152 m). Additionally, hydrants must also be located within 12 feet (3.7 m) of the fire department access road. If you are interested in learning more about fire plans review, or want to become a Certified Fire Plans Examiner, take a look at our learning path explorer module, which provides some sample lessons. 
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