Topic: Building & Life Safety

People walking up and down stairs

Basic of Egress Stair Design

For many of us, walking up and down stairs is a routine part of our day. We may use stairs at work, at entertainment venues, and in our home without thinking twice about how their design and function contribute greatly to life safety in both emergency and non-emergency situations. Recently, I wrote about the details and the importance of handrail design for safe and efficient stair use. Here I will focus on other details of stair design including riser height, tread depth, stair width, stair landings, and construction uniformity that are mandated in order to create a safe path of travel when using the stairs to move throughout the building. These standard stair design details are mandated for egress stairs in the exit access, exits and exit discharge. (Where you have other than standard stairs such as curved stairs, spiral stairs or winders within a means of egress, consult NFPA 101, Life Safety Code, Chapter 7 for further details on their design.) Construction All stairs serving as required means of egress must be of permanent fixed construction (unless they are stairs serving seating that is designed to be repositioned, such as those in theaters, for example, where seating sections are added, removed, or relocated and it is impractical for stairs associated with that seating to be of fixed, permanent construction). In buildings required by NFPA 101, Life Safety Code, to be of Type I or Type II construction, each stair, platform, and landing, not including handrails and existing stairs, are required to be of noncombustible material throughout. Stairs can be of combustible construction if the building is not required by that occupancy to be of Type I or Type II construction. For example, an occupancy might not have any requirements related to minimum building construction type, or the occupancy chapter might permit Type III, Type IV, or Type V construction. If the building is required to be of Type I or Type II construction, the materials used for new stair construction (stairs, platforms, and landings) must be noncombustible. Dimensional Criteria and Uniformity Providing adequate width is one of the most important features of egress stair design as the width ensures that the stairs can accommodate enough people safely and efficiently during an evacuation.  Providing appropriate stair riser height and tread depth ensures that stairs are safe, usable, and presents tripping and discomfort when traveling up or down the stairs.  The minimum required width as well as other dimensional criteria for both new and existing stairs is summarized in the tables below (reference: Chapter 7 of NFPA 101).  It should be noted that in some cases, the egress capacity will require a stair to have a greater width than the minimum specified here. The minimum width of new stairs is 36 in. (915 mm) where the total occupant load of all stories served by the stair is fewer than 50. Where new stairs serve a total cumulative occupant load (assigned to that stair) of 50 or more people but less than 2000 people the minimum width is 44 in. (1120 mm) and where the total cumulative occupant load assigned to the stair is greater than or equal to 2000 people the minimum width is 56 in. (1420 mm).  Riser height is measured as the vertical distance between tread nosings. Tread depth is measured horizontally, between the vertical planes of the leading projection of adjacent treads and at a right angle to the tread’s leading edge. Measuring both riser height and tread depth needs to represent the actual space available to those using the stairs. It cannot include any part of the tread that is not available for someone to place their foot.  Installing floor coverings to existing stairs might also reduce the available space for use on the stairs. Irregularities in stair geometry, either from one step to the next or over an entire run of stairs, can cause accidents, tripping and falling when using the stairs. When many people are using the stair at once, just one accident can cause delays and disruptions in movement and use of the stairs, and increase the overall time of evacuation. There should be no design irregularities. Very small variations due to construction are permitted between adjacent treads and risers and the overall different over the entire flight of stairs. The variation between the sizes of the largest and smallest riser or between the largest and smallest tread depths shall not exceed 3∕ 8 in. (9.5 mm) in any flight. Stair Landings As a general rule, stairs must have landings at door openings because it is unsafe to move through a door opening and immediately begin vertical travel on a stair. In existing buildings, a door assembly at the top of a stair is permitted to open directly to the stair, without first providing a level landing, provided that the door leaf does not swing over the stair (rather, it swings away from the stair) and the door opening serves an area with an occupant load of fewer than 50 people. Stairs and intermediate landings must continue with no decrease in width along the direction of egress travel. A reduction in width of a stair landing could reduce the overall capacity of the stair.  In new buildings, every landing will have a dimension, measured in the direction of travel, that is not less than the width of the stair. Landings are not required to exceed 48 in. (1220 mm) in the direction of travel, provided that the stair has a straight run. Intermediate stair landings serve as effective breaks in runs of stairs, which allow persons who slip or trip to halt their fall.     Stair Tread and Stair Landing Surfaces Surface Stair treads and landings must be solid, without perforations, except for noncombustible grated stair treads and landings as otherwise provided in the following occupancies: assembly, detention and correctional, industrial and storage. Solid treads and solid landing floors provide a visual barrier that shields the user’s view of the vertical drop beneath the stair. People with a fear of high places are more comfortable using these stairs. Grated and expanded metal treads and landings could catch the heel of a shoe and present a tripping hazard. Noncombustible, grated stair treads are permitted in areas not accessed by the general public, such as catwalks and gridirons in theaters, resident housing areas in prisons, factories and other industrial occupancies, and storage occupancies. Projections Stair treads and landings must also be free of projections or lips that could trip stair users. The tripping hazard occurs especially when someone is traveling down the stairs, where the tread walking surface has projections. The installation of a surface-mounted stair nosing or a strip of material onto an existing stair tread might produce a projection that creates a tripping hazard. Tread nosings that project over adjacent treads can also be a tripping hazard. (Additional considerations for minimizing tripping hazards for accessibility is also addressed in ICC A117.1, Accessible and Usable Buildings and Facilities.) Traction Stair treads and landings within the same stairway must have consistent surface traction. This means that slip resistance is reasonably uniform and sufficient to minimize risk of slipping across the treads. Consistency is important because misleading a person’s expectation of the surface they will be walking on is a major factor in missteps and falls involving slipping. Materials used for floors that are acceptable as slip resistant generally provide adequate slip resistance where used for stair treads. If stair treads are wet, there is also increased danger of slipping, just as there is an increased danger of slipping on wet floors of similar materials. The many details of stair design may seem minute and unimportant in the overall picture of fire and life safety, but stairs can be dangerous and an impediment to egress if not designed correctly.  Tripping, falling, and a lack of confidence by those using egress stairs can interrupt efficient egress travel and building evacuation.  Paying careful attention to stair design will greatly contribute to occupant safety during both day to day and emergency conditions

NFPA wins six 2021 Brandon Hall Group HCM Excellence Awards for its training programs

NFPA won six coveted Brandon Hall Group [Gold/Silver/Bronze] awards for excellence in the “Certification Program, Advanced Custom Content, and Best Use of Virtual Worlds for Learning” categories. The 2021 Brandon Hall Group HCM Excellence Awards are bestowed upon organizations that excel in learning and development, talent management, leadership development, talent acquisition, human resources, sales performance, diversity, equity & inclusion, and future of work. The following NFPA training solutions were recognized this year: Certified Fire Protection Specialist (CFPS) Online Learning Paths: Gold - Best Certification Program Certified Fire Plan Examiner (CFPE) Online Learning Paths: Gold - Best Certification Program Certified Fire Inspector I (CFI-I) Online Learning Paths: Gold - Best Certification Program NFPA 70, National Electrical Code (NEC) (2020) Online Training Series: Silver - Best Advance in Custom Content Fire and Life Safety Operator Online Training: Silver - Best Use of Virtual Worlds for Learning NFPA 70E, Standard for Electrical Safety in the Workplace (2021): Bronze - Best Advance in Custom Content                             “Brandon Hall Group Excellence Awards in 2021 provide much-needed and well-deserved recognition to organizations that went above and beyond to support their stakeholders during the unprecedented disruption of the COVID-19 pandemic,” said Brandon Hall Group COO and leader of the HCM Excellence Awards Program Rachel Cooke. “The awards provide validation of best practices in all areas of HCM at a time when they have never been more important to employers, employees, and customers.” In 2018 and 2019, Brandon Hall Group recognized NFPA online learning solutions related to sprinklers, storage, hot work, and NFPA 3000™, Standard for an Active Shooter/Hostile Event Response (ASHER) Program with awards. The 2021 award entries were evaluated by a panel of veteran, independent senior industry experts, Brandon Hall Group analysts, and executives based upon these criteria: fit the need, design of the program, functionality, innovation, and overall measurable benefits. “NFPA has been on a journey to improve its online education offerings so that skilled professionals keep learning during the pandemic and beyond. It’s an honor to have Brandon Hall Group recognize the educational transformation underway at NFPA and our efforts to improve work performance and safety with a total of 10 best in class awards over the past three years,” said Bartholomew Jae, the association’s director of education and development. “NFPA is in good company with progressive organizations such as Google, Bridgestone, Deloitte, HP, PepsiCo, and others receiving Brandon Hall Group honors this year. Perhaps even more rewarding is the praise we are receiving from the individuals and organizations who are embracing our new online training offerings.”

Modifications To Existing Sprinkler Systems

With many businesses rethinking how their office spaces will be utilized post-pandemic, a significant number will likely undergo renovations or redesigns. Add this to regular tenant fit outs, including shell space in newly constructed buildings, and there are sure to be thousands of existing sprinkler systems  requiring modifications to adequately protect redesigned spaces. This often raises the question as to what extent the sprinkler system must be brought up to date with the latest standard, whether the system needs to be recalculated, and how extensive the testing of the modified system must be. Fortunately, the 2019 edition of NFPA 13 dedicated a chapter to the requirements for these instances for the first time and that information will carry over to the soon-to-be-issued 2022 edition. Change of use/occupancy For the purpose of this discussion, we will focus on situations where the use or occupancy classification of the space is not being changed. Where that is the case a more complex analysis is likely required to determine the impact of changes to design densities, areas of operation, and several other possible changes. NFPA 25, Standard for the Inspection, Testing, and Maintenance of Water-Based Fire Protection Systems places responsibility on the owner for ensuring an evaluation be conducted in these instances, many of which go beyond the reconfiguration of office space where the space protected is likely to remain a light hazard occupancy. General When a building is undergoing a renovation or a remodel of its space the removal or addition of walls, partitions, and ceilings can negatively impact the effectiveness of the originally designed sprinkler system. In these instances, numerous sprinklers must often be relocated or added in order to appropriately protect the reconfigured space. This does not necessarily mean that the entire system must be reevaluated to ensure complete compliance with the latest edition of the standards. In fact, portions of the existing system that are not subject to the modifications can be considered previously approved under the retroactivity clause of NFPA 13, Standard for the Installation of Sprinkler Systems and do not need to be evaluated. Whenever additions or modifications are made to an existing system, enough of the existing system must be indicated on the plans to make all conditions clear for the AHJ to evaluate. This means that one of the first steps taken in these instances should be to gather as much of the existing plans and calculations, as is available. A more complex analysis might be required for the entire system if the original design basis cannot be confirmed. Hydraulic calculations While some have argued that minor modifications should not impact the system demand significantly enough to require calculations, NFPA 13 does require calculations be provided to verify that the system design flow rate will be achieved. Previous editions of the standard included an annex note indicating that it was not the intent to require a full hydraulic analysis of the existing sprinkler system, in addition to the new sprinkler layout. This note has been removed in recent editions. This still does not necessarily require a full set of hydraulic calculations particularly if the modifications are made in a part of the system that is not the most hydraulically demanding. In this case the modified portion of the system can be hydraulically calculated back to the branch line or riser to the point where original calculations are used to show that the design flow rate can be met.  This is not entirely clear in reading the standard especially without the previous annex note to point to so it is certainly worth checking with the local AHJ to determine what they will accept for these instances. Hydrostatic testing Newly installed sprinkler systems must be hydrostatically tested to check for leaks at a pressure of at least 200 psi (14 bar) for a period of at least 2 hours. When existing systems are modified such that the work affects less than 20 sprinklers, the system only requires testing at the system working pressure. Where the modification affects more than 20 sprinklers, that portion of the system must be isolated and tested at 200 psi (14 bar) for 2 hours. If the new work cannot be isolated, the testing can be done at system working pressure even if the modifications involved more than 20 sprinklers. In general, existing portions of the system do not need to be subjected to a new hydrostatic test. Striking a balance  Many buildings are routinely undergoing changes that can impact the fire sprinkler system and require modification of the system to adequately protect the space as it evolves. The provisions for existing system modifications in NFPA 13 are intended to ensure that the space has adequate coverage, the system demand can still be met, and the workmanship ofthe job has been completed well enough. This is meant to strike the appropriate balance between ensuring that the changes are not simply ignored, not throwing the entire latest standard out, and saying everything must be brought up to those requirements.
Wildfire in the background of a community

What to do if your home insurance is not renewed: up-to-date information for California policyholders

For many homeowners, choosing and purchasing property insurance is often a “set it and forget it” scenario. Federally-backed mortgage loans require homebuyers to purchase insurance, but how many homebuyers shop around for the best deal, discuss coverage details with an insurance agent, or think about looking for a new carrier after 5, 10, or 20 years? Dramatic, frequent, and increasing property losses due to wildfire in California are forcing policyholders to think differently about their insurance, since a growing number of companies are discontinuing or “non-renewing” residential property insurance policies in areas deemed at high risk. More and more California property owners are being forced to seek out insurance that adequately covers their risks at an affordable price. A new resource from Stronger California, an insurance trade coalition, can help consumers do just that. A new fact sheet on non-renewals helps homeowners understand their consumer protections under California law and gives helpful links for finding a new insurance carrier through a website or by talking to an agent or broker. It also directs consumers to options such as the California FAIR Plan and surplus lines insurers. Since a homeowner needs insurance to keep their mortgage, and most people cannot afford to rebuild and recover from a wildfire out of their own savings, it’s critical that consumers take action to educate themselves and seek out the best coverage they can afford. NFPA recognizes that property insurance is the primary and largest financial safety net for recovering from disaster-caused property damage including wildfires. It’s vital that insurance remains available to support the recovery and rebuilding of homes, businesses, and communities. While the insurance market in California is challenging, insurance experts are working to educate consumers about their choices as well as the things they can do to reduce their likelihood of wildfire loss and the possibility of losing their insurance coverage. The Stronger California coalition is calling on regulators, communities and insurers to work together on a comprehensive solution to the wildfire crisis, that ensures homeowners in high-risk areas have access to comprehensive coverage at competitive prices. Californians can learn more about what they can do to stay physically and financially prepared on their website.
Train at a station

Means of Egress with NFPA 130

NFPA 130 is the Standard for Fixed Guideway Transit and Passenger Rail Systems. It contains requirements for train stations, subway stations, the trains or subway cars themselves, and the tracks or paths these vehicles travel on. While NFPA 130 covers a wide array of topics this blog is going to concentrate on the unique means of egress requirements for fixed guideway transit and passenger rail stations. Means of Egress First, what is the means of egress? In layman’s terms the means of egress is the pathway out of a building or structure that leads to a point of safety and is comprised of three parts, the exit access, exit and exit discharge.    EXIT ACCESS - The exit access is the path that leads to the exit EXIT - The exit is the portion of a means of egress that is separated from all other spaces of the building or structure by construction, location or equipment as required to provide a protected way of travel to the exit discharge. Examples include an exit door that leads directly outside, an exit staircase, exit passageways, etc. EXIT DISCHARGE - Exit discharge is that portion of a means of egress between the termination of an exit and a point of safety. In NFPA 130 the point of safety can either be the concourse or a point of safety outside of the building. In general, the station needs to comply with the means of egress requirements in NFPA 101®, Life Safety Code®, for New Assembly Occupancies except where it is modified by NFPA 130. For more information on the means of egress check out this blog! The following sections discuss those modifications. Occupant Load Determining the occupant load is needed to figure out how quickly those occupants can egress the station. To determine the occupant load we need to assume that all of the trains are simultaneously entering the station full of passengers who need to disembark and that there is a full train’s worth of people waiting on the platform to enter the train. So, the occupant load includes both the people exiting the train as well as those waiting on the platform. This will give us a worst-case scenario of having all of the trains recalled to the station at once and having to evacuate both the vehicle and station. There is also the occupant load for each platform that must be calculated in order to make sure each platform can be evacuated in a timely manner. This number is based on peak ridership numbers, which can often require an analysis be done to determine peak ridership statistics. Similar to the station occupant load, the platform occupant load needs to assume a full train has pulled into the station and drops off an entire train load while there is another train load of people waiting on the platform. Evacuation Time When looking at evacuation times there are two main figures that must be considered. The first is the platform evacuation time which is required to be less than 4 minutes. The second is the station evacuation time, in which the occupant load needs to be able to reach a point of safety in under 6 minutes.  Travel Distance There are also limitations on travel distances and common paths of travel for platforms. Travel distance is your natural path of travel measured from the most remote point on the platform to the where the means of egress path leaves the platform. NFPA 130 requires that the travel distance is 100m (325ft) or less. There is also the concept of a common path of travel which is measured in the same manner as travel distance but terminates at that point where two separate and distinct routes become available. The common path of travel is not allowed to exceed 25m (82ft) or one car length, whichever is greater. Platforms Corridors & Ramps Many of the requirements for platforms, corridors and ramps are summarized in the table below. In addition to those limitations, when calculating available egress capacity on platforms, corridors, and ramps, 12 inches must be subtracted from each wall and 18 inches subtracted from the platform edge.   Capacity Travel Speed Minimum width Platforms 2.08 p/in.- min (0.0819 p/mm-min) 124 ft/min (37.7 m/min)   44 in. (1120 mm) Corridors 2.08 p/in.- min (0.0819 p/mm-min) 124 ft/min (37.7 m/min)   44 in. (1120 mm) Ramps 2.08 p/in.- min (0.0819 p/mm-min) 124 ft/min (37.7 m/min)   44 in. (1120 mm) Concourse   200 ft/min (61.0 m/min)   Stairs   48 ft/min (14.6 m/min)* 44 in. (1120 mm) Escalators 1.41 p/in.-min (0.0555 p/mm-min) 48 ft/min (14.6 m/min)*   Elevators carrying capacity for 30 minutes     *Travel Speed for vertical component of travel Escalators NFPA 101 typically doesn’t allow escalators to be used as a component in the required means of egress but because of the short evacuation timeframe, NFPA 130 allows it. When determining egress capacity for escalators there are a few rules that need to be followed. One escalator at each level must be assumed to be out of service and escalators cannot account for more than 50% of the egress capacity for a level unless they meet additional criteria. Elevators Elevators are another unique component of the means of egress that is allowed to be used in fixed guideway and passenger rail stations, but they also come with additional rules. One elevator must be considered out of service, elevators can’t account for more than 50% of the egress capacity and one elevator must be reserved for the fire service. The capacity of elevators is determined by calculating the carrying capacity over a 30-minute timeframe. Elevators also must meet certain construction requirements and they need to be accessed through holding areas or lobbies. Exit Hatches Exit hatches are another unique component of the means of egress permitted for fixed guideway and passenger rail stations. Exit hatches must be manually opened from the egress side with only one releasing operation requiring less than 30lb (130N) of force and have a hold-open device. It also needs to be clearly marked on the discharge side to prevent blockage. Fare Barriers Fare barriers are typically gate type or turnstile type, each of which have additional requirements that must be met to be allowed in the means of egress. Fare barriers are a unique characteristic of a station and have unique requirements. For a fare barrier to be allowed in the means of egress it must either be designed to release in the direction of travel during an emergency or be able to open by providing 15lbf (66N) of force in the egress direction. Platform Edge Provisions Finally, the platform edge is another unique feature of a station. Guards are not required along the trainway side of the platform edge. Certain horizontal sliding platform screens or doors are permitted to separate the platform from the trainway, but the doors or screens must open with less than 50 lb (220N) of force at any stopping position of the train and it needs to be able to withstand the positive and negative pressures caused by the passing trains. There are many unique fire and life safety elements found in Fixed Guideway Transit and Passenger Rail Systems. This blog discussed some of the unique means of egress characteristics, but NFPA 101 contains many more requirements that must be followed. 
Workers at a construction site

Latest NFPA Podcast Highlights Benefits of Using a New Online Tool That Helps Communities Assess their Safety Ecosystem and Address Gaps Before a Disaster Strikes

In early August, Meghan Housewright, the director of the NFPA Fire & Life Policy Institute announced the launch of the new Fire & Life Safety Ecosystem Assessment Tool that is helping users identify gaps in their community’s capacity to support safety and draw on the results to advocate for specific changes that will better protect citizens and property. The free tool comes on the heels of a recent report from the Policy Institute, “The Year in Review: A look at the events of 2020 through the lens of the NFPA Fire & Life Safety Ecosystem” and both the tool and the report are helping serve as important resources for safety professionals across the globe to understand and apply the Ecosystem in their daily roles. Last week, Angelo Verzoni from NFPA Journal talked with Meghan about the safety ecosystem, the assessment tool and its benefits, and why the tool was created with communities in mind. The conversation is included in the latest episode of the NFPA Podcast, and is featured in an article, “Eco Assessment,” in the latest issue of the magazine. Read the short article and listen to the podcast (the interview with Meghan and Angelo starts at 30:37) and share it with others you know. Find more information and related resources about the Fire & Life Safety Ecosystem at nfpa.org/ecosystem.                  
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