An area of refuge is one way to satisfy the accessible means of egress requirements. One of the most common questions when it comes to areas of refuge besides “What is an area of refuge?” is “Do the exit stairs need to be oversized?” Like so many other code questions the answer is “It depends.” It is going to depend on what is serving as your area of refuge. Before diving into some key requirements for an area of refuge and identifying what triggers the need to increase the size of the exit stair, for those wondering what area of refuge means and when one might be required, check out my previous blog, “Accessible Means of Egress and the Life Safety Code.” Regardless of what is considered the area of refuge, there are a few things that all areas of refuge have in common. The first is that they must comply with the general means of egress requirements found in Section 7.1 of the 2021 edition of NFPA 101®, Life Safety Code®. This section outlines a number of requirements including things like minimum headroom heights, levelness of walking surfaces, and the reliability of the means of egress. Additionally, two-way communication systems are required in areas of refuge. The exact location of the systems will depend on what is being used as an area of refuge. The system itself, though, needs to allow for communication between the elevator landing and either the fire command center or a central control point that has been approved by the authority having jurisdiction (AHJ). Directions outlining how to use it, how to request help using the system, and written identification of the location all need to be posted next to the two-way communication system. One key component of determining what can be considered an area of refuge is whether or not the building is protected throughout with an automatic, supervised sprinkler system. Area of Refuge in a Building Protected Throughout by Sprinklers If the building is equipped with sprinklers, then an entire story in the building can be considered an area of refuge provided certain criteria are met. The first is that each elevator landing needs to have a two-way communication system. It also must be equipped with both audible and visible signals. The story must have at least two accessible rooms or spaces that are separated from each other by smoke-resisting partitions. It is important to note that some occupancies, such as new and existing business, exempt the minimum two accessible rooms provision. This means that in those occupancies, only one room or space needs to be accessible. If an occupancy exempts the two accessible room provision, it will typically appear in the XX.2.2.12 paragraph of the occupancy chapter. Area of Refuge in a Building Not Protected Throughout by Sprinklers An area of refuge in a building not protected throughout with sprinklers must meet the specific requirements of 7.2.12.2 and 7.2.12.3. While I can’t cover every single requirement outlined in those particular sections, I will highlight key aspects. The first deals with accessibility. The area of refuge must be situated in such a way that an occupant has access to a public way, by using either an exit or an elevator, without having to go back through building spaces that he or she already passed through. Additionally, the area of refuge must be accessible via an accessible means of egress. This means that travel to the area of refuge cannot involve stairs. An occupant needs to be able to reach the area of refuge by traveling over either level floor or ramps. This also requires careful consideration of available clear widths, particularly through doors. Typically, an accessible route requires 32 inches (810 mm) of clear width through a door. In some existing buildings, door openings may only be 28 inches (710 mm). The narrower door opening can be challenging for occupants using wheelchairs to navigate and may not be considered an accessible route. If the area of refuge relies on the use of stairs to reach the public way, then the clear width of landings and stairs must be at least 48 inches (1220 mm). The clear-width measurement is taken between the handrails and must be maintained at all points below handrail height. There are two exceptions to the 48-inch (1220-mm) minimum width. The first is where the area of refuge is separated from the remainder of the story by a horizontal exit. The second is for existing stairs and landings. For existing landings and stairs, a minimum clear width of 37 inches (940 mm) must be provided at and below handrail height. If the area of refuge relies on the use of an elevator to reach the public way, then the elevator must be approved for firefighters’ emergency operations. Additionally, the power supply must be protected against interruption from a fire in the building that originates outside the area of refuge. Lastly, the shaft housing the elevator must be a smokeproof enclosure. There are two exceptions to the smokeproof enclosure requirement. The first is for areas of refuge that are larger than 1000 ft2 (93m2) and that are created by a horizontal exit. The second exception is for elevators in towers. A tower is a structure that meets a very specific definition and is not occupied by the general public. There is a separate set of criteria for elevators in towers. Regardless of whether an occupant will reach the public way via exit stairs or an elevator, a two-way communications system must be provided. Any doors providing access to the area of refuge must have a sign. The area of refuge sign must read “AREA OF REFUGE,” display the international symbol of accessibility, have a nonglare finish, and have letters that contrast with the background. Further specifics for the sign are outlined in ICC A117.1, Accessible and Usable Buildings and Facilities. The sign(s) must be illuminated. Tactile signage is also required at each location. Additional signs are required wherever necessary to clearly indicate the direction of travel to an area refuge and at every exit not providing an accessible means of egress. The image below is an example of an area of refuge sign; however, tactile signage would also be required. Another key aspect of an area of refuge is the presence of wheelchair spaces. Each area of refuge needs to have one wheelchair space that measures 30 inches x 48 inches (760 mm x 1220 mm) for every 200 occupants the area of refuge serves. The wheelchair spaces are not permitted to infringe on the required width of the means of egress for the occupant load served and must never reduce the width to less than 36 inches (915 mm). Each wheelchair space must be accessible without having to pass through more than one adjacent wheelchair space. This is where our original question of “Do the exit stairs need to be oversized?” will be answered. The one scenario where you may need to increase the size of your stair is when the building is not sprinklered and you are using the exit stair as an area of refuge. If that particular area of refuge serves 350 people, then two wheelchair spaces would be required. The image below shows what this could look like. The oversized stair comes into play because the means of egress needs to maintain the required width for the occupant load or at a minimum of 36 inches (915 mm). This would include the stair landing. If an area of refuge is less than 1000 ft2 (93 m2), then it needs to be proven that tenable conditions can be maintained within the area of refuge for at least 15 minutes when the separation creating the area of refuge is exposed to the worst-case fire scenario for that occupancy. Tenable conditions can be proven through either calculation or testing. The last aspect of an area of refuge we will cover for a non-sprinklered building is separation. Each area of refuge must be separated from the remainder of the story by a minimum 1-hour fire resistance rated fire barrier. There are two exceptions to this. The first is that when a higher rating is required elsewhere within NFPA 101. The second is if the barrier is an existing barrier with at least a 30-minute fire resistance rating. An example of where a higher rating would be required is if the exit stair enclosure is serving as the area of refuge and the enclosure requires a 2-hour fire resistance rating based on the number of stories it serves. The barriers and all openings in them must minimize air leakage and resist the passage of smoke. Door assemblies in these barriers must have at least a 20-minute fire protection rating. A greater rating is required where other portions of NFPA 101 require a higher rating. The doors must be either self-closing or automatic closing. All new fire door assemblies serving an area of refuge must be smoke leakage rated. Ducts are permitted unless other provisions of NFPA 101 prohibit them. If ducts penetrate the barrier, smoke-actuated dampers or some other approved means of resisting the transfer of smoke into the area of refuge must be provided. Summary There are a number of different configurations for an area of refuge. The presence of or absence of automatic sprinklers will be a driving factor in what can be considered an area of refuge. Regardless of what is considered an area of refuge, it is important to remember that it is just one way to provide an accessible means of egress.

From 1927 until 1963, what is now NFPA 101®, Life Safety Code®, was called the Building Exits Code. Although it now covers a variety of topics, there is still a large focus on the means of egress within NFPA 101. For upper stories, we often think of exit stair enclosures as the primary exit option. But what about people with mobility impairments, such as those who use a wheelchair? How does the Life Safety Code protect people with mobility challenges? The Life Safety Code is not intended to be an accessibility code; however, there are some accessibility requirements for new buildings that have areas accessible to people with severe mobility impairments. Generally speaking, these buildings would require at least two accessible means of egress unless one of the conditions for a single means of egress can be satisfied.   NEW! Watch a related video from the NFPA LiNK YouTube channel.   What is an “accessible means of egress”?   An accessible means of egress is defined as a means of egress that provides a path to an area of refuge, a horizontal exit, or a public way. The path must comply with NFPA 101 and ICC A117.1, Accessible and Usable Buildings and Facilities. While the definition is very specific as to what constitutes an accessible means of egress, a designer still has the choice in how to satisfy the need for accessible means of egress.   Access to a public way   Accessible means of egress in single-story buildings tend to be easier to provide. A door with a path to the public way could be considered an accessible means of egress. If there are elevation changes, providing ramps instead of, or in addition to, stairs ensures the path remains accessible. In the image below, a single-story building utilizes ramps to accomplish the elevation change between the building and the public way.     However, ramps or direct access to the public way are not always viable options. The code also allows for the use of a horizontal exit or an area of refuge.   What is a “horizontal exit”?   A horizontal exit is defined as “a way of passage from one building to an area of refuge in another building on approximately the same level, or a way of passage through or around a fire barrier to an area of refuge on approximately the same level in the same building that affords safety from fire and smoke originating from the area of incidence and areas communicating therewith.” A horizontal exit uses fire-rated construction to separate occupants from the dangers associated with fire. Because fire-rated construction is used, there is often no need for an elevation change. A horizontal exit could be located in the middle of a story allowing an occupant to simply travel through a fire door in a fire-rated wall. There are a number of other criteria outlined in 7.2.4 of the 2021 edition of NFPA 101 that need to be met in order for something to be considered a horizontal exit. The image below shows an example of a horizontal exit that could serve as an accessible means of egress. The red wall would have a 2-hour fire-resistance rating and the door opening would need to be protected appropriately.     What is an “area of refuge”?   An area of refuge is defined as “either (1) a story in a building where the building is protected throughout by an approved, supervised automatic sprinkler system and has not less than two accessible rooms or spaces separated from each other by smoke-resisting partitions; or (2) a space located in a path of travel leading to a public way that is protected from the effects of fire, either by means of separation from other spaces in the same building or by virtue of location, thereby permitting a delay in egress travel from any level.” There are a number of ways to meet this, so be on the lookout for my next blog, which will discuss the different options for areas of refuge.   While NFPA 101 is not an accessibility code, it is necessary that people with disabilities have the ability to move to a safe location during a fire event or other emergency. The accessible means of egress requirements are there to ensure that happens. If you are interested in learning more about emergency evacuation planning for people with disabilities, check out this recently updated guide from NFPA.

Even though online shopping has become the norm in today’s digital age, many people have still been inside a shopping mall. While most shoppers have probably never experienced a mall fire firsthand, a quick google search shows that mall fires are actually fairly common—not just in the United States but also across the globe.  In June, a fire broke out in the Somerset Mall in Troy, Michigan. The fire started in the kitchen of a Capital Grille. Since then, there have been a number of other fires in malls, including two in October. One occurred on the upper floor of a mall in Islamabad, Pakistan, while another occurred in exhaust ventilation ductwork in a mall in Honolulu, Hawaii. Although a number of issues were reported in the Islamabad fire, such as obstructions to the means of egress, no one was killed in either of these incidents.  So how does NFPA 101®, Life Safety Code®, work to protect occupants in malls? Well, there are provisions specific to mall structures that can be found in 36/37.4.4 of the 2021 edition of NFPA 101. What is a mall? Often, the term “mall” is unofficially used to describe several different types of structures, including strip malls, enclosed malls, or even city-like malls that span millions of square feet. The Life Safety Code has particular definitions, though, meaning a structure may be described as a “mall” but not technically considered a mall per the code. Below are some key definitions from the Life Safety Code to review before diving into the requirements. Mall structure A mall structure is defined by NFPA 101 as “a single structure enclosing a number of tenants and occupancies wherein two or more tenants or tenant buildings have a main entrance into one or more mall concourses.” The code goes on to say that “anchor buildings shall not be considered as a part of the mall structure.” That definition uses the term anchor building, which is also defined by NFPA 101.  Anchor building  An anchor building is “a building housing any occupancy having low or ordinary hazard contents and having direct access to a mall structure, but having all required means of egress independent of the mall concourse.” A good example of an anchor building would be a department store that connects to a mall but that has its own dedicated entrances/exits. Again, the code definition of an anchor building uses another term—mall concourse. So what is a mall concourse? Mall concourse According to the code, a mall concourse is “a common pedestrian area within a mall structure that serves as access for two or more tenants and does not exceed three levels that are open to each other.”  A mall concourse can be open or enclosed. In order to be considered open, one of two conditions needs to be met. The first is that at least 50 percent of the total area of the perimeter walls and roof of the concourse are open to the atmosphere. The openings need to be evenly distributed over the length of the concourse and cannot be concentrated in one particular area. The second condition is that an engineering analysis shows that the smoke layer interface is at least 6 feet (1,830 millimeters) above the highest walking level surface open to the mall concourse. That minimum 6-foot (1,830-millimeter) smoke layer interface height must be maintained for 1.5 times the calculated egress time, or 20 minutes, whichever is longer. A mall can have multiple concourses, but each of those concourses can be open to no more than three levels. If a building has a concourse that connects more than three levels, it cannot be considered a mall concourse, which means the requirements and allowances in 36/37.4.4 cannot be applied.  Protecting a mall The provisions of 36/37.4.4 are only applicable to mall structures that are three or fewer stories in height. If a building meets the definition of a mall, then a designer may choose to utilize 36/37.4.4 but is not required to. The other option would be to protect the building as a multiple occupancy building in accordance with 6.1.14. The special provisions of 36/37.4.4, however, are intended to address the common design challenges and unique features of mall structures, such as travel distance, plastic signs, kiosks, smoke control, occupant notification, and automatic sprinklers.  Let’s take a closer look at some of the select requirements for new mall structures.  Travel distance Travel distance can be a challenge in mall structures, particularly on the mall concourse. The travel distance within the tenant space must comply with the occupancy chapter; the travel distance within these spaces is measured to an exit or to the mall concourse. An additional 200 feet (61 meters) of travel for enclosed mall concourses, or 300 feet (91 meters) of travel for open concourses, is permitted provided certain criteria is met. The criteria include requirements for minimum clear width for the mall concourse, minimum widths for exits, automatic sprinklers, construction of walls between tenants, and smoke control for mall concourses connecting more than two levels.  Many malls utilize exit passageways to help them comply with the travel distance requirements. An exit passageway is a protected path of travel with strict limitations placed on what openings, penetrations, and equipment is permitted in the exit passageway. If you were to take an exit stair enclosure and rotate it 90 degrees, so instead of running vertically, it ran horizontally, you would have an exit passageway. Plastic signs Unique to malls is the number of plastic signs present. To minimize the contribution of plastic signage to fuel load and fire growth, a number of restrictions are placed on plastic signs. Plastic signs are permitted to cover no more than 20 percent of the wall area facing the mall concourse. There are also maximum sizes for signs, minimum distances between signage and adjacent tenant spaces, and restrictions on the types of materials permitted. Kiosks Another unique feature of malls is the presence of kiosks. Kiosks, whether temporary or permanent, are considered tenant spaces and must comply with several requirements. There are requirements related to the construction materials of combustible kiosks, horizontal separation distances between kiosks, or groups of kiosks, and other structures, and a maximum area of 300 square feet (27.8 square meters) for each kiosk, group of kiosks, or similar structure. Roboshields via Wikipedia  Smoke control A smoke control system is required for all new enclosed mall concourses that connect more than two stories. While a smoke control system is required, there are options in how the system is designed. It could be a completely separate mechanical exhaust system, or it could be a mechanical exhaust system in conjunction with HVAC systems. Another option would be automatically or manually released gravity roof vent devices. The designer may choose to combine any of those types of systems or could choose another engineered system. Occupant notification At any time the mall concourse is occupied, the fire alarm system, once initiated, must either activate a general alarm in accordance with 9.6.3 (positive alarm sequence is permitted) or use voice communication or a public address system in accordance with 9.6.3.10. It should be noted that visible signals are not required in mall concourses. Automatic sprinklers A supervised automatic sprinkler system is required throughout all mall structures and all anchor buildings. The sprinkler system must be capable of having any portion of the system serving tenant spaces taken out of service without affecting the operation of the portion of the system that serves the mall concourse. Any shades, canopies, awnings, or similar structures in an open mall concourse must be protected with automatic sprinklers. Kiosks or similar structures within enclosed mall concourses must be protected throughout with automatic sprinklers. Conclusion The special provisions of 36/37.4.4 are there as an option for designers to use to help address the unique features of a mall. However, it is imperative that before utilizing these requirements, designers ensure the structures do in fact meet the definitions associated with mall structures.

A version of this blog written by Kristin Bigda, publications strategy director at NFPA, first appeared in 2016. The article has been edited to reflect more recent code editions. With Halloween quickly approaching, thoughts of candy, ghosts, and haunted houses are surely on your mind. While haunted houses may be an entertaining way to spend an October evening, there can be devastating consequences if a fire were to break out and proper protections aren’t in place. What are haunted houses and special amusement buildings? Haunted houses may be temporary in nature or permanently installed. Sometimes, they are used only near Halloween, while others may be open year-round. This was the case in the tragic Haunted Castle fire that occurred at a permanently installed, year-round haunted house located at a Six Flags amusement park in New Jersey on May 11, 1984. Eight teenagers died in that blaze.  To prevent a similar tragedy to the Six Flags haunted house fire, provisions were added to NFPA 1, Fire Code, and NFPA 101®, Life Safety Code®, to address special amusement buildings—the category in which haunted houses typically fall. According to the 2021 edition of NFPA 1, a special amusement building is “a building or portion thereof that is temporary, permanent, or mobile and contains a ride or device that conveys patrons where the patrons can be contained or restrained, or provides a walkway along, around, or over a course in any direction as a form of amusement or entertainment, and arranged so that the egress path is not readily apparent due to visual or audio distractions, contains an intentionally confounded egress path, or is not readily available due to the mode of conveyance through the building or structure.” A special amusement building is an assembly occupancy regardless of occupant load. Special amusement buildings often use special effects, scenery, props, and audio and visual distractions that may cause egress paths to become difficult to identify. In haunted houses, in particular, the presence of combustible materials and special scenery can also contribute to the fuel load and, may result in rapid fire spread should a fire occur.   “ Haunted houses use special effects, scenery, props, and audio and visual distractions that may cause egress paths to become difficult to identify What does the code say? Code provisions for special amusement buildings are found in Section 20.1.4 of NFPA 1. The code requirements for haunted houses are summarized below: Haunted houses must apply the provisions for assembly occupancies in addition to the provisions of Section 20.1.4. Automatic sprinklers are required for all haunted houses unless it is less than 10 feet (3050 millimeters) in height and has less than 160 square feet (15 square meters) of aggregate horizontal projections. If the haunted house is considered moveable or portable, an approved temporary means is permitted to be used for water supply.  Smoke detection is required throughout all haunted houses.  The actuation of any smoke detection device in a mobile or temporary haunted house must sound an alarm at a constantly attended location on the premises. A fire alarm system is required in all permanently installed haunted houses.   The fire alarm system in all permanently installed haunted houses must be initiated by required smoke detection, the required automatic sprinkler system, and manual means at a constantly attended location under continuous supervision by competent persons when the haunted house is open to patrons. Actuation of sprinklers, or any suppression systems, as well as smoke detection systems (having cross-zoning capability) must provide an increase in illumination of the means of egress and termination of other confusing visuals or sounds. The one exception is for haunted houses that are in permanently installed special amusement buildings that use a ride (or similar device) that occupants are contained in and unable to evacuate themselves without the help of a ride operator and that meet specific criteria. Exit marking and floor proximity exit signs are required. Where designs are such that the egress path is not apparent, additional directional exit marking is required. Interior wall and ceiling finish materials must be Class A throughout. Per Section 10.8.1, emergency action plans are required. Other requirements, not specific just to haunted houses or special amusement buildings, may also apply, such as:  Permits (see Section 1.12) Seasonal buildings (see Section 10.12) Special outdoor events, fairs, and carnivals (see Section 10.14) As we move into the Halloween and haunted house season, it’s easy to get caught up in the fun and overlook the safety issues that may arise. Through the provisions in NFPA 1, which can assist code officials and fire departments in enforcing safe haunted houses, and NFPA’s Halloween resources for consumers, everyone can stay safe this season.

The fire at a Thai nightclub in early August 2022 was all too familiar. It started during a live music performance killing 20 people and injuring 25. Many of the details emerging are eerily similar to The Station nightclub fire which claimed the lives of 100 people and injured 230 more in February of 2003. In both instances, flammable interior finish and blocked exits were believed to have played a role in the fast-spreading fires and high number of fatalities. The 2003 tragedy led to a number of changes to NFPA 101, Life Safety Code, while also reiterating the importance of interior finish and means of egress requirements for assembly occupancies. Interior finishes are the interior surfaces of a building that are generally secured in place like wall and ceiling coverings. They have proven to be a contributing factor in how quickly a fire spreads. To minimize the impact interior finish has on fire spread, Chapter 10 of the 2021 edition NFPA 101, Life Safety Code®, establishes basic requirements for interior wall, ceiling, and floor finishes. Chapter 10 outlines two testing options: 1) testing in accordance with NFPA 286, Standard Methods of Fire Tests for Evaluating Contribution of Wall and Ceiling Interior Finish to Room Fire Growth; or 2) testing in accordance with ASTM E84 or UL 723.  Paragraph 10.2.3.1.2 of the 2021 edition of NFPA 101, outlines acceptance criteria for materials tested in accordance with NFPA 286. The acceptance criteria includes: limitations on the spread of flames; peak heat release rate less than 800 kW; and for new installations the total smoke released throughout the test cannot exceed 1000 m2. Any material that meets the criteria outlined in 10.2.3.1.2 can be used wherever a Class A material is permitted. The alternative test method (ASTM E84 or UL 723) results in the material being grouped into a class. There are three classes- Class A, Class B, and Class C which are determined by a material’s flame spread index and smoke developed index. Class A materials will have the lowest flame spread index of the three classifications. The smoke developed index is the same range for all three classifications. For newly installed materials both the flame spread index and smoke developed index is considered, whereas for existing materials only flame spread index is considered. Occupancy chapters may further regulate interior finish beyond what is contained in Chapter 10. In both fires, acoustic material is believed to have been a major contributing factor in the rapid spread of fire. Assembly occupancies do further regulate interior finish. The requirements are the same for new and existing assembly occupancies. In general assembly areas with an occupant load of 300 or fewer, ceiling and wall materials must be Class A, B, or C. In general assembly areas with an occupant load of more than 300, and in corridors, and lobbies, interior wall and ceiling finishes must be Class A or B. In enclosed stairs interior finish materials must be Class A. One other contributing factor was the availability of exits. In both the fire in Thailand and at The Station nightclub, one of the doors to the outside was blocked for use by occupants to allow the band performing to have their own separate entrance/exit. One of the fundamental components of the Life Safety Code is the concept of free egress. Prohibiting people from entering the building via a door is one thing, but not allowing occupants to exit the building via the nearest door is unacceptable. Additionally, NFPA 101 prohibits the means of egress for assembly occupancies from going through hazardous areas such as kitchens, storerooms, closets, stages, and platforms. There are also requirements related to the size of a main entrance/exit, where one exists. History has shown that occupants tend to go out the way they came, even if there is an exit closer. The main entrance/exit provisions are intended to prevent crowd crush situations. In existing assembly occupancies, the main entrance/exit needs to be sized to accommodate at least one-half the total occupant load. For new assembly occupancies that are dance halls, discotheques, nightclubs, or that have festival seating, the main entrance/exits must be wide enough to accommodate two-thirds of the total occupant load. The main entrance/exit for all other new assembly occupancies must be sized to accommodate one-half the total occupant load. If the assembly occupancy is more than one level, then each level must have access to the main entrance/exit and that access must be sized to handle two-thirds (for new assembly occupancies) or one-half (for existing) of the occupant load of that level. The main entrance/exit requirements for certain types of new assembly occupancies was increased from one-half to two-thirds the total occupant load due to a crowd crush event during The Station nightclub fire. Another way the Life Safety Code strives to reduce the risk of crowd crush is by requiring trained crowd managers. All assembly occupancies, with the exception of certain ones used exclusively for religious worship, are required to have at least one trained crowd manager. Depending on the total occupant load, additional crowd managers may be required. Typically, there should be one crowd manager for every 250 occupants. Prior to the 2006 Edition, crowd managers were only required for assembly occupancies with occupant loads of more than 1000. After The Station nightclub fire, the Life Safety Code was changed to require at least one crowd manager for all assembly occupancies. Within 2 minutes of the fire starting at The Station nightclub, there was crowd crush at the main entrance/exit. This led to the main entrance/exit being almost completely impassable. The crowd manager’s responsibilities include understanding crowd management, understanding methods of evacuation, being familiar with the facility evacuation plan, being familiar with the emergency response procedures, and understanding procedures for reporting emergencies. While the cause of the recent fire at the Thai nightclub is still under investigation, The Station nightclub fire was caused by pyrotechnics. To reduce the risk of open flames or pyrotechnics starting a fire in an assembly occupancy they are prohibited unless certain conditions are met. In order for pyrotechnics to be used on stage before proximate audiences, precautions to prevent ignition of any combustible material, satisfactory to the authority having jurisdiction must be met and the use of the pyrotechnic device must comply with NFPA 1126, Standard for the Use of Pyrotechnics Before a Proximate Audience. As we have seen countless times, fires in assembly occupancies, and in particular nightclubs, can result in a high number of fatalities. By carefully considering the use of open flames and pyrotechnics we can eliminate potential ignition sources in these types of occupancies. Additionally, ensuring the interior finish requirements for assembly occupancies are met can help slow the spread of fire. Fires in an assembly occupancy have the added risk of leading to a crowd crush event. Compliance with the means of egress and crowd manager requirements will help reduce the risk of crowd crush events during emergency situations. 

Hazardous materials are those chemicals or substances that are classified as a physical hazard material or a health hazard material (see this blog for more information). There's often some confusion around what the appropriate occupancy classification is when hazardous materials are present. Unfortunately, there isn't a straight answer. It is going to depend on what code is applicable in your particular situation. This blog is going to take a closer look at the differences in occupancy classification when using NFPA Codes and the International Building Code (IBC). For some basic information regarding the differences in occupancy classification check out this blog. Before digging into the actual differences between the codes it's helpful to understand the concepts of maximum allowable quantity (MAQ) and control areas. Although NFPA Codes and the IBC both address these concepts in their own documents, the overall approach is similar. For a closer look at how to determine a MAQ using NFPA 1, Fire Code, be sure to look at this blog. NFPA Approach One of the major differences between the way the IBC and NFPA codes address occupancy classification for spaces using hazardous materials, is the actual creation of a unique occupancy classification within the IBC. NFPA codes do not create a separate occupancy classification specific to hazardous materials. Instead, regardless of whether they contain hazardous materials or not, all buildings are given an occupancy classification(s) based on how the space is being used and the expected characteristics of the occupants. Then, if the building contains hazardous materials additional provisions must be met. If the hazardous materials in a given control area exceed the MAQ, additional protections are required. These are called Protection Levels and they range from Protection Level 1 to Protection Level 5. It is important to note that although a building must comply with the additional protection levels, the occupancy classification itself does not change. This means when the MAQ is exceeded and NFPA documents apply, you are required to comply with both the requirements specific to that occupancy as well as the appropriate protection level requirements for that hazardous material. NFPA Approach- Protection Levels Features for Protection Level 1 through Protection Level 3 are intended primarily to provide protection from physical hazards. Protection Level 1 is the highest level of protection. This protection level is required when high hazard Level 1 contents exceed the MAQ. These materials are unstable and can pose a detonation hazard. Examples of high hazard level 1 contents include Class 4 oxidizers; detonable pyrophoric solids or liquids; Class 3 detonable and Class 4 unstable (reactive) solids, liquids, or gases; and detonable organic peroxides. This protection level requires that the materials be stored in a one story in height, detached building that is used for no other purpose. Protection Level 2 is designed to limit the spread of fire from materials that deflagrate or accelerate burning. Additionally, the protection features are designed to limit the potential for fire to spread from an outside source and affect the hazardous materials in the building. This protection level is required when high hazard Level 2 contents exceed the MAQ. These materials present a deflagration hazard or a hazard from accelerated burning. Examples of high hazard Level 2 contents include Combustible dusts that are stored, used, or generated in a manner that creates a severe fire or explosion hazard; Class I organic peroxides; flammable gases; nondetonable pyrophoric solids, liquids, or gases; and Class 3 water-reactive solids and liquids. Protection Level 3 is one of the most common protection levels encountered in the general inspection of storage and industrial operations that use hazardous materials. These types of operations and storage facilities normally operate with amounts of hazardous materials greater than the MAQ while conducting business. This protection level is required when high hazard Level 3 contents exceed the MAQ. These materials readily support combustion or present a physical hazard. Examples of high hazard level 3 contents include Class IIA, Class IIB, and Class III organic peroxides; Class 2 solid or liquid oxidizers; Class 2 unstable (reactive) materials; and oxidizing gases. Protection Level 4 is intended to mitigate the acute health hazards resulting from the storage, use, or handling of high hazard Level 4 materials. These contents include corrosives, highly toxic materials, and toxic materials. The objective is to protect evacuating occupants and arriving first responders from being injured by these hazardous materials. Protection Level 5 applies to semiconductor fabrication facilities. Buildings that require Protection Level 5 must comply with NFPA 318, Standard for the Protection of Semiconductor Fabrication Facilities. IBC Approach The IBC uses a High-Hazard Group H, occupancy classification for buildings that, among others, manufacture, process, generate, or store hazardous materials in excess of the MAQ in a control area. There are 5 sub-categories within the High Hazard Group H occupancy, H-1 through H-5 which closely resemble the protection levels in NFPA documents. IBC Approach- Occupancy Subclassifications H-1 is the subclassification for buildings that contain hazardous materials that pose a detonation hazard. H-2 is the subclassification for buildings that contain hazardous materials that pose a deflagration hazard or a hazard from accelerated burning. H-3 is the subclassification for buildings that contain hazardous materials that readily support combustion or that pose a physical hazard. H-4 is the subclassification for buildings that contain hazardous materials that are health hazards. H-5 is the subclassification for semiconductor fabrication facilities and comparable research and development areas. Although at first glance it seems like NFPA and the IBC handle things extremely different, the overall concepts are actually not all that different. The IBC creates an entirely separate occupancy classification while NFPA uses protection levels. In both cases, compliance with additional provisions is going to be required to minimize the risk associated with the presence of hazardous materials in those quantities.