AUTHOR: Robin Zevotek

Buildings

Do all buildings have to comply with the latest code?

When constructing a new building it is imperative architects, engineers, contractors, and owners follow the most current codes and standards to provide what is considered the current minimum level of safety for a building. This minimum level of safety is established most often by consensus codes and standards which have been adopted by the jurisdiction where the building is being constructed. These codes and standards are constantly evolving, adapting to new technology and addressing gaps in safety. But what about existing buildings? Do they need to be brought up to the adopted code? The answer is often complicated and depends on the local codes in place as well as the type of occupancy. An example of this complexity occurs when you examine requirements for existing buildings in NFPA 5000, Building Construction and Safety Code as compared to NFPA 101, Life Safety Code. Both codes define an existing building as “A building erected or officially authorized prior to the effective date of the adoption of this edition of the Code by the agency or jurisdiction” however, the two codes treat them very differently. Looking in Chapter 1 of both codes the scope and purpose statements provide direction as to where codes apply and their overall intent. NFPA 5000 would not apply to existing buildings unless they undergo a change in use, some level of building rehabilitation, an addition or if the building is relocated or damaged. NFPA 101 has no such clause and applies to both new and existing buildings. Thus, where NFPA 5000 focuses on the design and construction of new buildings, NFPA 101 applies to both new and existing buildings with a focus on safety during the entire lifecycle of the building not just the initial design and construction. Under NFPA 5000, Building Construction and Safety Code, buildings which have “been officially authorized” meaning they were designed and permitted in accordance with earlier editions of the building code, can remain in their original state. If they undergo the items mentioned earlier, they would be required to comply with the most current version of the building code. For example, the 2021 edition of NFPA 5000 requires all newly constructed one- and two-family dwellings to be protected with an automatic fire sprinkler system. This was first introduced in the 2006 edition; and earlier editions did not contain this requirement.  In areas were NFPA 5000 is adopted, existing homes authorized for use prior to the adoption of the 2006 edition are not required to be retrofitted with automatic fire sprinkler systems. This concept of “officially authorized” or existing buildings, is one of the reasons we continue to see fires with a significant number of injuries and deaths. It’s not that the current level of safety expected in new buildings isn’t enough, it’s that the vast majority of the buildings in the U.S. and many other countries around the world were constructed under what was considered the minimum level of safety at the time.  That level of safety has evolved but requiring all buildings to be retroactively improved to meet the current codes and standards may be costly and could impose a significant hardship on building owners. However, there are times where the risk will outweigh cost, for example, anywhere the 2021 edition of NFPA 101 has been adopted. In these jurisdictions, an automatic fire sprinkler system is required in all nursing homes, both new and existing, with very few exceptions. The code development process determined the risk to the occupants of these facilities is significant enough that providing automatic fire sprinklers in nursing home facilities is required to meet what is now considered the minimum level of safety for both new and existing buildings. As you can see, the answer to the question of whether an existing building must be improved to meet what is now considered the minimum level of safety can be found in that jurisdictions adopted code. The adopted code is often a suite of different codes and standards, which may include, building, fire, and life safety codes. It is important that these codes work together to set the minimum level of safety for all buildings in the jurisdiction. For more information on the importance of how code development and adoption improve safety while balancing risk check out the NFPA Fire And Life Safety Ecosystem.

Fire Department Use of Sprinkler Systems

At the first NFPA meeting in 1896 the first consolidated set of sprinkler installation rules were established, becoming what is today known as NFPA 13, Standard for the Installation of Sprinkler Systems. Formalizing the sprinkler installation standards increased fire sprinkler effectiveness, however, a gap still existed in the use of fire sprinkler systems. In 1933 a brochure titled “Use of Automatic Sprinklers by Fire Departments” was published providing fire departments with guidelines on how to best capitalize on the effectiveness of fire sprinkler systems during incidents. This brochure evolved over the next 33 years into the Recommended Practice for Fire Department Operations in Properties Protected by Sprinkler and Standpipe Systems, NFPA 13E first published in 1966. Today NFPA 13E provides the information necessary to ensure fire departments are trained on and operate effectively with automatic fire sprinkler systems. Although some fire sprinkler systems are designed to suppress a fire, most are designed to control a fire. The main difference between fire control and fire suppression is related to the fire sprinkler systems impact on the fires heat release rate. The graph below depicts fire control (dotted line) versus fire suppression (solid line). Fire sprinklers controlling a fire result in a steady heat release rate, keeping the fire from growing, and fire sprinklers suppressing a fire will result in a decreasing heat release rate. The three principal causes of fire sprinkler system failures identified in NFPA 13E are a closed control valve, inadequate water supply for the system and occupancy changes that render the installed system unsuitable. Beyond the primary causes found in the recommended practice, NFPA has conducted research on the U.S. Experience with Fire Sprinklers to help understand fire sprinkler effectiveness. Let’s take a second to review the three main causes found in the recommended practice all of which responding fire department personnel can impact positively. Closed control valve Familiarization with the types of control valves and their layout in a system allows firefighters to both understand what valves will disrupt water flow and what position have they should be in for effective operation. Should they encounter a valve which is not in the correct position during a fire, placing that valve in the correct position may restore the system effectiveness. This is not a hard and fast rule however, since the fire may have already operated more sprinkler heads than the available water supply can support, making the system ineffective. Additionally, fire departments should never turn off a sprinkler system that has activated until they have confirmed the fire is fully extinguished and overhaul has taken place. Even if ventilation is needed to increase visibility and conduct search and rescue, the system should remain operational to control the fire as these tasks occur. Once this occurs, steps should be taken to identify if only a portion of the system needs to be shut down (a zone) rather than the entire system. Anytime the system is shut down a firefighter with a portable radio should remain at the control valve to immediately open the valve should the fire not be fully extinguished. Simply turning the system back on may not reestablish fire control. Fire sprinkler systems are designed to control a fire utilizing a specific number of sprinklers at a design pressure and flow. If the system is shut off prior to the fire being extinguished the potential exists for additional heads beyond the design to activate. When the system is turned back on the available water supply may not cover the operated heads leading to ineffective water application and a fire that is no longer controlled. Inadequate Water Supply The water supply may be inadequate due to a lack of available water flow, lack of available pressure or both. Since fire department pumpers often have the capacity to supply water at higher flow rates and pressures than the normal water supply, utilizing a fire department pumper to supply water to the fire department connection (FDC) can address most inadequate supply concerns. The FDC will often bypass many of the control and check valves in the system, supplying water directly to the operating sprinklers. NFPA 13E recommends a pressure of 150 psi (10 bar) to effectively suppl fire sprinkler systems, unless additional signage is provided to indicate a different pressure. The fire department can also have a negative impact on the water supply to a fire sprinkler system. Although fire sprinkler systems are designed with a hose stream allowance or amount of water the fire department may potentially need to fully extinguish the fire, this may not be sufficient. For more information on fire flow check out this blog Calculating the Required Fire Flow. The hose allowance accounts for water needed at the base of the fire, which if the fire department cannot effectively apply water to the base of the fire, more may be needed. Utilizing more water from the supply than accounted for has the potential to reduce the sprinkler system effectiveness, eliminating its ability to control the fire, resulting in fire growth and the need for more water. Supporting the system through the FDC ensures that even if more water is needed than the original allowance, the sprinkler system still has an available supply at an effective flow and pressure. Occupancy changes Although the fire department does not have an ability to impact occupancy changes during a fire incident, an effective preplan and inspection program has the potential to identify occupancy changes which can adversely impact fire sprinkler system effectiveness before fires occur. Training those conducting these inspections to understand what types of commodities would represent a high heat release rate fire and how to identify if a sprinkler system could be designed to deliver the necessary water density can reduce this potential cause of failure. Summary As with all NFPA recommended practices, the language is less rigid than a standard or code, utilizing “should” instead of “shall” as to not limit the individual fire departments, allowing them to adopt more effective procedures. Familiarization with NFPA 13E provides anyone who may be utilizing a fire sprinkler system the knowledge necessary to positively impact the systems effectiveness.  Check out NFPA 13E to help your department identify the recommended training and operations for those responding to emergencies involving activated fire sprinkler systems. Interested in learning more, check out the resources below for additional information on fire sprinkler systems and fire department access. Sprinkler system Basics: Types of Sprinkler Systems The Basics of Sprinkler Thermal Characteristics Types of Sprinklers NFPA 1: When is Fire Department Access Required?
Building Evacuation Sign - green

Building Occupants - Should they stay, or should they go?

At the first indication there may be an emergency, many argue the best course of action is to evacuate all the occupants immediately, however, as buildings increase in size and complexity this question, like emergencies themselves, is challenging, and the best course of action is not straight forward. Thus, it is important to pre-plan an evacuation strategy prior to an emergency occurring. For buildings required to have an emergency action plan, an evacuation procedure is required along with drills to ensure occupants (employees and guests) are aware of the approved strategy (NFPA 1 – Fire Code [1:10.8.2.1]). The development of an emergency action plan is the responsibility of the building owner; however, it must be approved by the AHJ (for more information about Emergency Action Plans check out this blog). When a building is not required to have an emergency action plan, it is still important to pre-plan the evacuation procedure. There are four main strategies when it comes to occupant safety, each named for their intent: Total evacuation. Phased Evacuation. Occupant Relocation. Shelter-in-place. Total Evacuation One of, if not the most common strategy is total evacuation where all the occupants are directed to immediately exit. Its most effective in less complex buildings, where evacuation occurs as emergency responders are in route. Since buildings are smaller and less complex, any potential conflicts with occupants exiting and access for responders are minimal. As building size and complexity increase, the number of occupants and time to total evacuation increases, making the total evacuation strategy less applicable. Phased Evacuation An alternate to total evacuation is the phased evacuation where occupants are directed to exit in groups, typically starting with those closest to the emergency and working away. More often used in larger buildings such as high-rises, this strategy accounts for the increased time required to evacuate. Occupants closest to the emergency are given priority use of the exits, followed by those in less danger.  Typically, the fire floor and one or two floors above and below are evacuated first. Additional floors are then evacuated as necessary, usually by doing one additional floor above and below at a time. Evacuation is often conducted over a longer period, requiring active management so that emergency responders are not competing for access while occupants exiting. Occupant Relocation When occupants are incapable of evacuation possibly due to a medical conditions or physical restraint the occupant relocation strategy can be utilized. It is typically employed in buildings with both active (fire sprinkler) and passive (smoke/fire barriers) protection providing safe locations for occupants within the building during an emergency. This includes the use of areas of refuge as discussed in NFPA 101 Life Safety Code. Shelter-in-place Like occupant relocation and phased evacuation, the shelter-in-place strategy involves utilizing the protection provided by the building, both passive and active, as well as the distance from the emergency to protect occupants in place. The difference being occupants are remaining in place, until the emergency is mitigated. Depending on the size of the building and type of emergency, evacuation may never be required. An example of this could be a residential high-rise where occupants several floors removed from the fire remain in their apartment until the fire is controlled. The occupants away from the emergency.  When a shelter-in-place strategy is employed emergency responders, in conjunction with facility personnel (if applicable) should continue to re-evaluate the situation and decision to employ said strategy. If the smoke/fire are spreading into occupied areas rescue from the fire department or total evacuation may be necessary. When occupants are directed to shelter in place it is important to communicate to the need to be patient as controlling the fire and removing the smoke can take an hour or longer. In a fire or other emergency event, if occupants are located near the fire or emergency, they should be directed to take every action possible to remove themselves from that area. If safe exits are not available and the building can provide some protection facility personnel and emergency responders may choose to utilize another evacuation strategy. Communicating the strategy and practicing via drills ensures that everyone is familiar with increasing occupant safety in an emergency. Every situation is slightly different making evacuation a complex decision. For more information on building evacuation check out these NFPA resources: How to make a home fire escape plan NFPA FAQs about building evacuation High-rise Apartment & Condominium Safety

Means of Escape in Residential Fires

The tragedy in Philadelphia two weeks ago, where 12 individuals lost their lives in a two-family home fire, underscores the importance of exit requirements in residential buildings ( including one-and two-family dwellings, apartments, hotels, and board and care facilities). Let’s take a moment and review means of escape concepts a in these types of occupancies and the importance of establishing and practicing home fire escape plans. Keep in mind, code requirements in your specific area may vary from this guidance; however, the concepts are often very similar. What are the exit requirements? The requirements for exits in residential occupancies pertain to those that are  inside a residential unit, also known as a dwelling unit, and those applicable once an occupant is outside the dwelling unit. Inside the dwelling unit, the means of escape criteria provides a way out of the dwelling unit in an emergency – this criteriais a less stringent requirement than its counterpart, means of egress. Means of egress is an occupant’s way out of the building once outside their personal dwelling unit. As occupants spend a significant amount of time in their homes, they tend to be more familiar with the layout of their particular space, thus reducing the need for the more stringent requirements found in means of egress. However, means of escape will still be required. The concept of escape and egress is used in one- and two-family dwellings, lodging or rooming houses, apartments, hotels and dormitories, board and care facilities, and daycare homes as they are covered in NFPA 101®, Life Safety Code®.  This blog will focus on the requirements for the means of escape that are foundational to those residential occupancies. Whenever a dwelling unit has more than two rooms, all living and sleeping areas are required to have a primary and secondary means of escape unless 1) the room has access directly to the exterior via a door leading to ground level or 2) the dwelling unit is fully protected by an automatic fire sprinkler system. The primary means must provide unobstructed access to the outside at ground level via a door, stairway, or ramp. This is almost always also the main entrance into/out of the dwelling unit. The secondary means of escape is intended to provide an alternate route in an emergency if the primary means becomes blocked. The four options for a secondary means of escape include: another primary means of escape or, passage through an adjacent non-lockable space which has an approved means of escape or, a window or, a bulkhead from a basement level. The figure below illustrates the concept of primary and secondary means of escape. When a doorway is part of the means of escape it must be a minimum of 24 in (61 cm) wide for bathrooms and rooms under 70 ft2 (6.4 m2) all others must be a minimum of 28 in (71.1 cm) wide. The height of all doors must be a minimum of 6.5 ft (1.98 m). Doors can be sliding or swinging and must not be locked against egress except with approved release mechanisms. In new dwelling units not protected throughout with an automatic fire sprinkler system where the area of a story exceeds 2000 ft2 two primary means of escape, located apart from each other are required. Providing windows as a means of escape is a common way to fulfill the secondary means of escape requirement, especially on lower floor levels.  An operable window may be used as a secondary means of escape provided it is: within 20 ft of the ground or directly accessible by fire apparatus or -opens onto an exterior balcony or if below ground level, has a window well. Home Fire Escape Plan Developing a home fire escape plan is one mechanism of identifying and communicating the means of escape in your residence. Code required means of escape provides an opportunity; however, it is important that occupants know where they are, how to access them quickly, and to practice using them regularly. Gather everyone you live with and take some time today to identify the primary and secondary means of escape in each living and sleeping space. Ensure they are not blocked by storage or furniture; the locking mechanisms, if permitted, operate easily, and everyone can use them. Schedule some time to practice using both the primary and secondary means. For more on how to develop your plan check out How to make a home fire escape plan from NFPA. Summary Codes require safe ways out of a residence in the event of an emergency, planning for them is the responsibility of the architect or engineer designing the structure, installing them is the responsibility of the contractor, verifying the installation is the responsibility of the inspector, but knowing how to use them is the responsibility of all occupants. For information on the code requirements check out NFPA 1 and NFPA 101, and visit our public education site for more information on home fire escape plans and other public education messages. References Dwelling Unit - One or more rooms arranged for complete, independent housekeeping purposes, with space for eating, living, and sleeping; facilities for cooking; and provisions for sanitation [NFPA 1]. Means of Escape - A way out of a building or structure that does not conform to the strict definition of means of egress but does provide an alternate way out [NFPA 1, NFPA 101]. Means of Egress - A continuous and unobstructed way of travel from any point in a building or structure to a public way consisting of three separate and distinct parts: (1) the exit access, (2) the exit, and (3) the exit discharge [NFPA 101]. Important Notice: Any opinion expressed in this blog is the personal opinion of the author and does not necessarily represent the official position of NFPA or its Technical Committees. In addition, this piece is neither intended, nor should it be relied upon, to provide professional consultation or services.
Highrise buildings through the clouds

Egress Challenges Related to Assembly Spaces Located at the Top of High Rise Buildings

The best views of the urban landscape are often from the top floors of the area's high rise buildings. This real estate has become sought after for restaurants, multi purpose rooms, large corporate meeting areas and even tourist attractions. Assembly spaces such as these, located on the top floors of high rise buildings combine the hazards of high occupant density with the egress concerns of high rise buildings, creating challenges in egress design as well as facility operators. This blog will review how NFPA 101, Life Safety Code provides guidance on mitigating these challenges effectively.  What is an assembly space? When 50 or more individuals can gather in a space for uses such as entertainment, eating, drinking, or deliberation, the area is considered an assembly occupancy. This type of use may involve dense occupant loads, ten times that of a business occupancy and more than ten times as dense as residential occupancies. The occupants of assembly spaces are often first-time visitors who are unfamiliar with the location and availability of egress. When is a building considered a high rise? Any building containing an occupied floor which is more than 75ft above the lowest level of fire department vehicle access, would be considered a high rise building. The 75 ft value corresponds with the highest level most common fire department aerial apparatus can reach. Total evacuation of these buildings can take anywhere from tens of minutes to hours depending on their size. Design considerations In the United States, new high rise buildings must incorporate fire protection of the structural elements. This is typically accomplished with the use of non-combustible or limited combustible construction (Type I & Type II). The building must also be protected throughout with an approved automatic fire sprinkler system, class I standpipe system and voice communications fire alarm system. All vertical exit enclosures in high rise buildings must be designed as smoke proof enclosures. Additionally, the entire building requires emergency/standby power as well as an emergency command center.  In the case of an assembly space, located on the top floor of a high rise building, the occupant load of the assembly space will drive the means of egress requirements for the entire building. The table below shows how the number of required exits increases as the occupant load increases. Even a medium size assembly dining room or bar may require three exits, which continue to the level of exit discharge. This can take up valuable real estate in the building all the way to the ground floor as shown in the building section below. Table 1: Minimum Number of Exist (NFPA 101 7.4) Number of Occupants Minimum Number of Exits <500 2 500-1000 3 1000> 4     Figure 1: Minimum number of exits example (NFPA 101 Handbook) Depending on the type of assembly space, the main entrance/exit may need to be sized to accommodate ½, or even ⅔rds of the occupant load. After considering the number of exits, exit sizing, and the need for exit remoteness (required distance between exits) the inclusion of the assembly space on the upper floors can drastically impact the egress requirements. Although elevators may not count as a means of egress, consideration may be given to their use in evacuating occupants in immediate danger. The design of the elevator enclosure as well as system functions may depend on if this use is by emergency personnel, staff or building occupants. Facility operators considerations Once a building is constructed and occupied, the facility management team is often tasked with ensuring an adequate level of safety is maintained. For assembly spaces in high rise buildings good facility management involves a comprehensive emergency action plan (EAP). At a minimum this includes how emergencies are reported, the response to emergencies by staff and occupants, and the evacuation procedures for all types of emergencies. Emergencies may be detected automatically, in the case of a fire event, or may be reported to or witnessed by staff, which is often the case in medical emergencies. The EAP will detail the response including if/when first responders are notified and how staff shall direct occupants. Should evacuation be necessary the EAP provides guidance on when zoned evacuation is appropriate, where occupants are directed away from an emergency to lower floors, or if a full building evacuation is necessary. If equipped with elevators designed for evacuation, the EAP will recommend when their use is appropriate. For more complex incidents the emergency command center will be staffed to provide additional resources and command/control. Due to the complex nature of the EAP, regular drills for all types of emergencies are required to ensure proficiency.         In existing high rise buildings, the addition of assembly space may be possible if the Authority Having Jurisdiction (AHJ) is willing to establish a maximum occupant load based on the capacity of the means of egress. It is often the facility management team's responsibility to ensure the occupant load is kept below that level for any events conducted in the space and that appropriate egress is maintained. Summary The combination of densely packed occupants, unfamiliar with their egress, located above the level of fire department aerial apparatus in buildings which may take over an hour to fully evacuate present challenges for both designers and facility managers. The Life Safety Code requires many features which increase the level of safety in these occupancies. When these requirements are combined with good facility operations practices, assembly spaces at the top of high rise buildings can safely provide breathtaking views for occupants to enjoy.

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