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Escalator Falls (2020)

Chapter: Chapter 2 - Literature Review

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Suggested Citation:"Chapter 2 - Literature Review." National Academies of Sciences, Engineering, and Medicine. 2020. Escalator Falls. Washington, DC: The National Academies Press. doi: 10.17226/25899.
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5 Literature Review The literature review is a synthesis of findings related to airport escalator safety. The review includes an overview of escalator safety, escalator incidents, mitigations, airport design and operations, and training. The section concludes with results from the review of findings and includes a discussion of staff training, public service announcements, and best practices, as well as identifying emerging issues that will require additional research. Overview of Escalator Safety There have been two key papers, both published in 2008, addressing airport escalator safety. These two papers addressed most of the same issues as the synthesis study. Cameron Nicolson, in 2008 at the Calgary International Airport (YYC) in Canada, wrote a paper for fulfillment of credentials for the International Association of Airport Executives Canada in 2008 (Nicolson 2008), and Ginga Griffin of ESIS Global Risk Control Services wrote a paper on escalator safety (Griffin 2008). Both papers covered management of airport risk and escalator safety. A telephone interview with Ginga Griffin on October 25, 2019, revealed some of the findings. Airport Versus Transit Escalator safety research or information on maximizing escalator safety in an airport terminal is limited. However, there is substantially more research on maximizing escalator safety in mass transport hubs (MTHs) such as train stations and subway stations. The similari- ties between airport terminals and MTH suggest that some of the MTH escalator safety research may be applicable to airports, as both airports and MTHs experience crowding and rushed conditions. MTHs and airports are not, however, perfectly analogous. In addition to being rushed, airport users often carry baggage, something that can make using escalators more hazardous. Airports also have a high proportion of passengers who are infrequent users of the terminal, as well as meeters and greeters who are nonpassengers and are usually not counted in the statistics of people using an airport. Also, air carrier and terminal employees are not included in the terminal passengers’ numbers. International airports have passengers who may come from countries where people drive on the left side of the road and are accustomed to using escalators that operate in the same fashion. Since North American airport escalators typically follow the local convention of right- hand travel, this introduces a source of potential confusion for people trying to find the correct escalator operating in the direction they are accustomed to. There are data that report inci- dents of people intentionally or mistakenly trying to use the escalator going in the wrong direc- tion. Although airports and MTHs have some differences, the similarities are sufficient to allow airports to learn from and apply many of the lessons learned in MTH escalator safety research. C H A P T E R 2

6 Escalator Falls Escalator incidents at airports and MTHs are well known, and most studies on the subject were published more than 10 years ago. Human behavior is the most common cause of accidents and incidents on MTH escalators. The most common type of incident are falls by older passengers and entrapments by young children. Risk Management Airport operators have both a financial and moral obligation to find solutions to eliminate and/or reduce the incidence and severity of escalator injuries as low as reasonably practicable (ALARP) (Nicolson 2008). Escalators have many advantages over elevators in an airport terminal, but injuries associ- ated with escalators—though rare—are many times more common than those associated with elevators (Nicolson 2008). Although the per-use escalator-injury occurrence rate is low, high passenger volumes suggest that one or more escalator injuries may occur every month within larger airports (Nicolson 2008). Other airports with escalators have reported even more frequent escalator incidents. According to the Comparison of Risk and Function of Escalators and Elevators, escalators provide a common mode of personal transport in airports and other settings. According to the National Elevator Industry, Inc. (2019), there are approximately 44,000 escalators in the United States and Canada or 35,000 units in the United States compared with a million eleva- tors in the United States and Canada or 900,000 units in the United States. Despite the greater number of elevators, people use escalators more often than elevators. The 35,000 escalators in the United States transport 105 billion passengers per year, or 3 million trips per escalator, far more than the 18 billion passenger trips by elevators, or 20 thousand trips per elevator (National Elevator Industry, Inc. 2019). Public-related accidents occur more commonly on escalators than on elevators; sources differed as to the exact numbers for escalators compared with elevators. There are more worker-related fatalities on elevators than escalators. Even after correcting for the number of rides per year, escalators continue to have a greater accident/incident rate of 0.221 accidents per installed escalator versus 0.015 accidents per installed elevator (Elevating Studio 2018). The escalator incident data show that the one safety feature needed for every escalator is an elevator. For those people who cannot properly—or should not—use an escalator, an eleva- tor becomes the safer and often more time-efficient option. Generally, research shows that the group of passengers at an elevated injury risk when using escalators includes people who use wheelchairs or other wheeled mobility devices, people with baby strollers or carts, people with both baggage and young children, and older people. Airports should work to direct and encourage these individuals to use an elevator. Every escalator should have an elevator in close proximity that is easy to locate and can be accessed from either end of the escalator. If the elevator is difficult to find, or is too far away, people will likely opt to use the escalator because of the lack of an apparent elevator option. When installing an escalator in an airport, ensure that an elevator option is in close proximity. (Nicolson 2008) For risk management, interventions that target escalator falls hold the greatest promise for impact on the overall incidence of falls and understanding the causes of these falls can contribute to the devel- opment of effective interventions. (Nicolson 2008) Airports with pre-existing escalators should ensure that an elevator option is obvious to airport users. If an elevator option is not obvious, the wayfinding to the elevators must be improved to ensure the elevator option is well delineated at each end of the escalator. In order to discourage higher risk escala- tor users, the airport elevators should be large enough to accommodate carts, strollers, wheelchairs, and baggage. Baggage carts, strollers and shopping carts are especially hazardous on escalators because they are difficult to control and can lose part or all of their entire load, and when something falls off

Literature Review 7 a cart, it becomes a hazard to other escalator users, as it tumbles down the escalator. By comparison, elevators have an injury rate of just fifteen yearly injuries per 1,000 elevators or fifteen times less risk of injury than escalators. (Nicolson 2008) Escalator Incidents The section on escalator incidents reviews human factors issues, focusing on young children and older passengers. The section also discusses the impacts of baggage fee policies and mobile devices on escalator incidents and presents other topics, including incident data, entrapment, and a summary of difficulties passenger encounter when using escalators. The Consumer Product Safety Commission estimated that 75% of escalator injuries resulted from falls, 20% from entrapment at the bottom or top of an escalator or between a moving stair and escalator sidewall, and the remaining 5% of incidents categorized as “other,” including sudden stops of the escalator and reversal of direction (McCann 2013). Although there is a belief that the most critical part of the escalator is the step gap—leading many different manufacturers to reduce or avoid this gap—all the statistics and information consulted clearly show that falls are the main cause of accidents on escalators (42% to 88%, depending on the source). Falls not only cause the highest number of accidents but also cause more severe injuries and more fatalities than other types of accidents (Cooper 2005; Ruibal et al. 2015). However, other literature contradicts this statement and finds that the “caught-in” or entrapment incidents generally result in more serious injuries than do falls, and children were more often involved in these types of incidents. The children’s injuries were mostly caused when a child’s hands or footwear, including dangling shoelaces, became caught in an escalator comb plate at the top or bottom of an escalator, or in the space between moving stairs and an escalator sidewall (Williams and Sevenants 2015). Human Factors and Demographics Understanding the risks for airport falls could lead to effective mitigation, which in turn could be generalizable to a large number of airports, and other public places (e.g., subway stations and shopping malls) worldwide (Howland et al. 2012). In a study of escalator falls at a Metropolitan Airport in 2009 to 2010, 44% of the falls occurred on escalators. The demographics reported are consistent with data from many other airports: most of the passengers who fell were identified as female, and most were over 65 years of age. The study team examined whether escalator falls differed from falls at other airport locations by injury type. Escalator falls were significantly more likely than other falls to result in lacerations (46% vs. 24%), but less likely to result in soft tissue injuries (43% vs. 64%; p = 0.001). Escalator and non-escalator falls were about equal in terms of the percent resulting in no injuries (8% vs. 7%). The study illustrated several key issues. Airports have very large numbers of people flowing through terminals on a daily basis. Even when the relative risk for an individual is very small, significant risk can occur. This number is apt to increase due to population aging and the number of older adults who have the means to travel, and older adults are at greatest risk for escalator falls in particular. (Chi et al. 2006) National data on older-adult escalator injuries show that the risk is related to age, and that those over 75 years have greater rates of escalator falls than those between the ages of 65 and 75 years (O’Neil et al. 2008). Many of the references for airport escalator falls also refer to seminal study analyzing 194 escalator-related falls at Taipei Metro Rapid Transit stations. The study concluded that the majority of falls were due to distraction, loss of balance, and not holding handrails while riding the escalator (Chi et al. 2006).

8 Escalator Falls Eight airport fire/rescue personnel were interviewed for a study of escalator falls at a metropolitan airport in the United States. The results of the interviews are consistent with other observations regarding potential emerging issues affecting escalator incident frequency (Howland et al. 2012). These issues include health impacts, increases in the average age of passengers, baggage fees, increasing use of mobile devices, and other passenger distractions. Health Impacts Many older adults fear flying, which may result in “air terminal anxiety” (Low and Chan 2002). Older adults are more likely than younger passengers to experience travel-related anxiety (McIntosh et al. 1998). Hyperventilation resulting from the anxiety may cause lightheadedness and dizziness, which in turn could compound other risks for escalator falls. Follow-on discussions with airport risk-management staff have not shown a relationship between escalator falls and physiological changes resulting from long flights. Staff mentioned that falls resulting from medical conditions induced by flying are more likely to occur on the boarding bridge and in the gate area immediately after leaving the aircraft rather than on an escalator later in the journey. Aging Travelers Two studies by O’Neil et al. (2008) and Steele et al. (2010) examined elevator- and escalator- related injuries among adults age 65 and older using data from the Consumer Product Safety Commission’s National Electronic Injury Surveillance System (NEISS). The NEISS collects injury data on consumer products from selected hospitals nationwide. The O’Neil study found an estimated 39,500 escalator-related injuries and no deaths to people over age 65 from 1991 to 2005, which is an average of 2,633 injuries per year. Almost all the injuries were caused by a slip, trip, or fall. During this study period (1991–2005), the rate of escalator injuries doubled (O’Neil et al. 2008). The second study by Steele et al. found an estimated 44,870 elevator- related injuries from 1990 to 2006, an average of 2,639 injuries per year. More than half of the injuries were caused by a slip, trip, or fall (Steele et al. 2010). Three-quarters of the injuries in both studies involved women (McCann 2013). Baggage Fees There are anecdotal observations that passengers are carrying more baggage through airport terminals and gates checking large bags to avoid baggage fees. Statistics on the impact changes in airline baggage fees have on the amount of checked baggage are changing, particularly as airlines improve baggage tracking. It is difficult to determine whether passengers are carrying more or less baggage through the airport after check-in. However, airport passengers typically have more baggage than metro transit passengers. Riding an escalator while attempting to hold onto bags on a different step engages hands that might otherwise hold the railing. Additionally, the center of balance of someone holding baggage may be different from someone not carrying baggage. For people whose balance and strength are already compromised by aging, using an escalator with baggage may reduce their ability to recover equilibrium if they start losing balance. Mobile Devices Increasingly, people in airports use their mobile devices to store boarding passes and when travelling to and from aircraft. Using a mobile device while carrying baggage on an escalator increases the potential for a fall. However, even without bags, using a mobile device engages hands and diverts attention from holding onto handrails and increases distraction when

Literature Review 9 stepping on or off escalators. Thus, the user of a mobile device is at risk for a fall or of causing others to fall by inadvertently bumping into them. Hands-free mobile-device use may partially mitigate some of this risk but is not likely to affect distraction issues. Direction of Travel It is difficult to infer from the incident data the impact on the direction of travel and incidents, but claims experts suggest that escalators moving in the “up” direction have more incidents. This may be because these falls often result in backward falls down the escalator and may involve other people on the escalator. Entrapment of Shoes, Clothing, and Body Parts For many years, entrapment has been a major escalator incident issue. Entrapment incidents are often a result of body parts such as children’s hands or dog paws, as well as baggage straps, loose clothing, long dresses, scarves, coats, and certain types of footwear being caught in moving parts of the escalator. Most common of all is footwear—in particular, soft-rubber-soled shoes, flip-flops, and rubber boots. Most of this footwear has a soft-soled base that causes the sole to become squashed on the step tread, which has been known to then become a trapping point at the comb plates if the passenger does not lift their foot before exiting the escalator (Williams and Sevenants 2015). The step-to-step transition point at the bottom and top curves of the escalator are known to cause entrapment of shoes, especially soft-soled flip-flops. The passenger may have their foot placed too close to the leading edge, and as the soft sole presses into the step tread, the step passes through this transition point and has the potential to grab the shoe (Williams and Sevenants 2015). The other common location of entrapment is the side of steps between the moving step and the skirting panel. Adding to this issue is that passengers often misuse the skirting brush to clean their shoes. This can cause the shoe to become trapped between the skirt panel and step, hindering the movement to and from the escalator (Williams and Sevenants 2015). Passenger Difficulties Using Escalators The Airport Passenger Conveyance Systems Planning Guidebook, published as ACRP Report 67, includes information relevant to this synthesis study. Airport Passenger Conveyance Systems Planning Guidebook Section 2.2, titled Escalators, lists the following passenger difficulties: 1. Crowding and congestion—With passengers having to pause and wait for other passengers to board the escalator, waiting passengers could not properly prepare for the device. This was most often associated with a passenger boarding the device with baggage and not being able to see the device prior to boarding. There would often be added pressure for the passenger to move quickly as there were additional passengers behind him/her in line. 2. Families with small children—Children often have very limited experience with escalators, espe- cially in an airport environment. Typically, the parent(s) would allow the children to go first or board simultaneously (which is the better approach from a safety point-of-view). When a child was apprehensive about the device, this family would cause a blockage at the device. If the parent(s) already boarded the escalator and the child refused to board, a more significant problem occurred— Parent(s) were now trying to go in the opposite direction of the device while the child stood at the entry to the device. 3. Strollers—Strollers were regularly taken onto an escalator, and the typical effect was that they took up a bit more space. However, parents were observed boarding the escalator with the child still in the stroller rather than looking for or taking an elevator. This is a major safety issue, especially in the downward direction. While some parents successfully balanced the stroller

10 Escalator Falls (positioning themselves on the downward side of the stroller), we observed a few incidents where the child fell out of the stroller, and the resulting scene was chaotic. No injuries resulted from any of these incidents. 4. Wayfinding—Passengers typically use conveyance devices only when they are directly visible or clear wayfinding exists. In instances of poor wayfinding conditions, passengers were observed to use inappropriate devices (e.g., using strollers on escalators) in lieu of traveling to a non-obvious device such as an elevator. 5. Balance/fall—A passenger fell at the bottom of an escalator which caused the next few passengers to tumble over him before someone could get the escalator turned off. For the average person, it is not obvious that turning off the escalator is a two-step process, thus even a few more seconds passed (and a few more passengers fell) before the escalator stopped. 6. Baggage Carts—It is a rare occurrence at American airports when passengers take a baggage cart onto an escalator, but it does occur. This type of incident can be very hazardous, with situations observed in other countries where baggage fell off of heavily loaded carts while traveling up or down escalators. To prevent this problem in European airports, it is common to place bollards in the floor surrounding the entry landing of escalators to physically prevent baggage carts from reaching these vertical circulation units. (TransSolutions, LLC, et al. 2012) The use of baggage carts or trolleys on escalators was studied by David Cooper in a graduate thesis in 2005. In some European airports, the baggage carts or trolleys are designed for use on escalators. However, U.S. airports prohibit the use of baggage carts and trolleys on escalators. The report noted two major issues: the challenge of accessing appropriate incident data and the use of trolleys on escalators (Cooper 2005). Incident Data Research on the topic of “accidents on escalators” showed a lack of common reporting or recording criterion for escalator accidents. As a result, the data content is inconsistent, making it difficult to establish a basis for comparison. In addition, most of the reports focus on the consequences of accidents and passenger data but do not describe the characteristics or condition of the escalator. In contrast, the European Lift Association (ELA) has been collecting accident data from its partners since 2008 using a common template. The many inconsisten- cies between the data might be the result of escalator manufacturers providing the main data, as they might be reluctant to declare accidents on their equipment. When ELA report data are cross-checked with data from different sources, the data suggest that the ELA data might not be transferrable to the airport environment (Ruibal et al. 2015). Studies from the ELA indicate a need to collect reliable escalator accident data to help iden- tify potentially dangerous situations and sources of risk for users or technicians on escalators. Accident investigation is a preventive action initiated by the prior existence of an accident. Its importance is in the objectivity of the data: an accident indicates the actual existence of a hazard and therefore a risk. The registration of these cases and incidents and their statistical treatment provides evidence of where, when, and how many accidents are occurring. Analyzing accident and incident data might suggest why they occur. Within the province of Ontario, Canada, the Technical Standards and Safety Authority (TSSA) is responsible for regulating the safety of more than 43,000 elevating devices in Ontario (Nicolson 2008). These elevating devices include elevators, escalators, moving walks, lifts for persons with physical disabilities, passenger ropeways, construction hoists, and ski lifts. There is no national reporting standard for escalator incidents in the United States, which makes data and comparative statistical analysis more difficult. A legislated requirement to report incidents makes the TSSA a noteworthy source of Canadian escalator safety infor- mation. Between 2008 and 2019, the TSSA reported 44 permanent injuries and one fatality, which occurred in 2010, for escalators and moving walkways. In 2018, there were no reported

Literature Review 11 fatalities or permanent injuries (TSSA 2019). The relatively low number of injuries caused by defective equipment may be attributed to the high maintenance standards mandated by the TSSA (Nicolson 2008). Mitigations The review of the literature and incident reports from North American airports showed a lack of incident causation attributed to either escalator design or maintenance. Improvements in escalator safety reflected new escalator standards, designs, and products leading to improved signage and reduced entrapment. Escalator Standards The standard for elevators and escalators, ASME A17.1-2016–Safety Code for Elevators and Escalators, is often updated (recently in 2016). The guidelines in ASME A17.1-2016, which incorporate the industry’s expertise, serve as recommendations for elevators in the United States. However, in many parts of the United States, local laws require adherence to the lat- est version of ASME A17.1. In Canada, ASME A17.1-2016 functions as Canadian Standards Association (CSA) B44-16. This has been incorporated into the National Building Code of Canada, the rules of which have attained legal status by their adoption in certain provinces (ANSI 2016). In addition to the revised ASME standards, the American Public Transit Association (APTA) also developed Heavy Duty Escalator Design Guidelines (APTA 2019). These guidelines help transit agencies to specify heavy-duty escalators for use in the transit environment. However, some airports use the APTA standards when specifying escalators. The revised APTA guide- lines incorporate or exceed the ASME standards and are a voluntary code of requirements for escalators. The section below beginning with operational requirements is extracted from the APTA guidelines and is relevant to airport operations. B. Operational requirements 1. Hours of operation should be considered as 24 hours per day, seven days per week. 2. Escalator components should be designed based on the design loads as defined in ASME A17.1. (as amended). 3. Direction of travel should be considered as either direction and unit should be up-and-down reversible. 4. Rated speed should not exceed 100 feet per minute (fpm). The no-load-to-full-load speed should not exceed 4 percent of the rated speed. General A. In a single contract, efforts should be made to provide escalators from a single manufacturer. The contractor shall furnish and install escalators that shall comply with the following requirements: 1. Vertical rise: As shown on contract drawings. 2. Nominal step width: 1,000 mm (40 in.) or 800 mm (32 in.). 3. Speed: Not to exceed 100 feet per minute (fpm). 4. Flat steps: Three minimum for less than 10 m (32 ft., 10 in.) rise; four minimum for greater than 10 meters (32 ft., 10 in.) rise (APTA 2019). General A. In addition to the minimum requirements given in the codes, the installer shall design the steps for a minimum load of 320 lb. (145 kg) per 40-in. step or 256 lb. (116 kg) per 32-in. step with an ultimate strength safety factor of 8. B. The steps shall carry the load under maximum concentric and eccentric loading conditions without failure (APTA 2019).

12 Escalator Falls The APTA guidelines are consistent with the findings reported in ACRP Report 67: Airport Passenger Conveyance Systems Planning Guidebook (TransSolutions, LLC, et al. 2012). Escalator Configuration New escalators reflect the new standards and are built to reduce design factors that may contribute to incidents. Mitigations include wider steps of 48 inches and a maximum speed of 100 feet per minute (fpm). In addition, to facilitate transitions on and off escalators, three or more flat steps at the top and bottom are recommended. New escalators often have three flat steps. For long escalators, four or five flat steps are recommended. Five steps might favor passengers traveling with luggage, but the efficacy of this needs further research. Speed Speed on virtually all escalators in an airport environment is limited to a maximum of 100 fpm (whereas that rate can approach 130 fpm for moving walkways) because of the safety element of a horizontal plane versus a rising plane. Speed on escalators anywhere is regulated largely in consideration of safety issues and hazards associated with each landing area. The speeds of most escalators are adjustable, and the actual operating speed may be established in consultation with the operations staff at the individual airport. Large transit systems in Asia and Europe often change the speed of the escalator depending on the time of day (Langham 2015). A study conducted by London Underground investigated the escalator wear and energy savings of variable speed reduction in addition to passenger safety issues. There are many human factor issues to consider when deciding on a strategy for variable speed. Acceleration, deceleration and jerk (the rate of change of acceleration) have a direct safety implication and require strict adherence to specified limits. There is a minimum safe transition time between speeds, which may cause delays during acceleration, and it is therefore advantageous to bring the step band up to speed before passengers reach the comb plate. Passenger balance when stepping on and off the machine may improve with a reduction in speed, as the relative speeds of the steps and landing will reduce. This will have the biggest impact on passengers who are elderly or disabled, and do not react as quickly to changes in balance. Conversely, passengers who use the Underground regularly may have an expectation of the speed of escalators and overcompensate for the required balance adjustment if it is running slowly. Whether passengers are aware of a reduction in speed, as well as the likelihood of walking or standing, will influence the optimum running speed. The perception of speed reduction is highly subjective and will vary from person to person, with the demographic of certain locations or times of the day making them more appropriate for a reduced speed strategy than others. Further work in this area would allow the human factor implications to be explored fully. (Langham 2015) Discussions with risk management personnel suggest that reducing the speed of escalators would improve safety. Several airports that responded to the survey had operating speeds between 80 and 100 fpm. Further research is needed to identify appropriate operating speeds for the airport environment. There is general agreement that operating speeds between 80 and 90 fpm reduce escalator incidents. The airport in Sarasota, Florida, reduced the escalator speed to 80 fpm, and the result has been a reduction in escalator incidents. Capacity and Stair Width Walking pedestrians do not change the capacity, given that the “boarding rate” is the capacity determinant, not the speed at which they move (TransSolutions, LLC, et al. 2012).

Literature Review 13 From ACRP Report 67 (Section 2.2.1.3, Step Width), Escalator manufacturers rate theoretical capacity based on speed, assumed occupancy per step, and 100% utilization; however, many studies show that 100% utilization is never obtained. Specifically, manufacturers use five people per four steps on a 32-inch-wide escalator, resulting in an area occupancy of 2.7 square feet per person (sfpp), and two people per step on a 48-inch-wide escalator, resulting in an area occupancy of 2.1 sfpp. In contrast, observed capacity is generally one person per every other step on a 32-inch-wide escalator and one person per step on a 48-inch-wide escalator, resulting in an area occupancy of 4 sfpp. (TransSolutions, LLC, et al. 2012, page 8) A 48-inch-wide step surface accommodates extra baggage and may be better for airports that experience a higher percentage of non-business passengers or are a tourist destination. Certainly in cases where an application within a non-secure environment is planned, and the average is more than 1.5 bags per person, the 48-inch-wide escalator should be considered (TransSolutions, LLC, et al. 2012). Escalator Maintenance Airport escalator-incident reports rarely cite maintenance of escalators as a contributing factor in passenger incidents. There is some reported incident data attributed to maintenance from transit systems and airports primarily in Europe. In accident reports that infer that the condition of the escalator is a factor in the accident, the escalators usually are more than 20 years old and located outdoors. Unlike transit applications, most airport escalators are typically located indoors in terminals and renovated frequently to accommodate increases in passenger demand. Airport terminals are updated, renovated, or replaced more frequently than transit facilities, and escalators also are replaced more frequently. High-Quality Equipment Escalator safety is improved through the use of high quality equipment. When installing a new escala- tor in an airport, ensure that the equipment choice is based on the total cost of ownership and not simply the upfront cost. The purchase cost of an escalator is usually much less than its total lifetime mainte- nance cost. Quality escalator and moving sidewalk equipment combined with a good maintenance pro- gram should allow the equipment to last for thirty years. Making purchasing decisions based on the total cost of ownership favors better quality equipment with better safety features. The MTH data suggest that the up-front cost of an escalator’s optional safety features is far more affordable when factored to include the overall cost of ownership. Furthermore, both airports and MTH operate around-the-clock, and there is a requirement for equipment maintenance to be done while the building is open to the public. Higher quality equipment generally has higher quality safety features and tends to be more reliable with less operating downtime. Choosing high quality escalators helps to improve customer service, reduces overall operating costs and reduces the risk to escalator users. A number of cost-effective safety features can be added to existing escalators and moving sidewalks, to minimize the safety hazards in all quality levels of escalators. These safety features have been tested in MTH and other facilities and are designed to actively limit the user’s exposure to known escalator hazards. (Nicolson 2008) Airport Design The design and layout of an airport terminal’s vertical change elements relative to passenger flow can directly influence escalator safety. Additional factors include signage and wayfinding, illumination levels, escalator congestion resulting from surge loads, overloading, and opera- tional issues such as location of baggage drop-off. In new construction or major renovations, it may be possible to locate all vertical change elements together. Spaces at the bottom and top of escalators should be designed to manage both normal and surging passenger flows. Proper location of passenger check-in and baggage drop-off sites is also important. Ideally, passengers should not encounter any vertical change elements before baggage drop-off or after baggage claim, but the reality is that this is not possible in many airport terminals.

14 Escalator Falls Vertical Change Elements The co-location of stairs, escalators, and elevators improves passenger flow and circulation. Many terminals are either designed or renovated to co-locate all vertical change elements. The proximity and visibility of the nearest elevator are better predictors of escalator injury rates than the volume of passengers using a particular escalator (Nicolson 2008). Adequate wayfinding and signage become even more important when co-locating or relocating vertical change elements is not possible. As mentioned previously, the use of remote baggage drop-off or locating check-in before vertical travel is required will also help to reduce escalator falls resulting from carrying baggage. The large renovation project at Minneapolis-St. Paul International (MSP) Airport, discussed in Chapter 4, illustrates another approach for reducing escalator falls. Both the airport and MTH literature discuss the importance of managing passenger flow at the entries to and exits from escalators. Surges in passenger flow are a common problem in MTH and air terminals served by interterminal trains. Airport operators need to ensure that there is sufficient space for passenger with baggage to wait to enter the escalators and enough movement to make sure that passengers do not back up onto escalators. The literature reviewed discusses the co-location of elevators and escalators, but there is no discussion on the co-location of stairs and escalators. The design of a barrier-free rapid transit system co-located stairs and escalators as a fundamental part of the station design. The design’s goal was to keep pedestrian traffic together. In the early 1980s, inclusive design goals focused on accommodating low-vision and blind passengers. Dog guides were trained to lead their person away from the escalator and to the stairs or elevators (Hunter-Zaworski 1989). Lighting or illumination levels were not mentioned as a major concern in the literature review of escalator incidents. Escalator manufacturers’ design literature offers many options for lighting of the escalators—from under-step lighting, handrail lighting, and entry and no-entry green and red lights. Difference Between Wayfinding and Escalator Signage To clarify context for this report, wayfinding includes signage that directs passengers to eleva- tors or other important terminal landmarks, and escalator signage refers to information that is either affixed to the escalator or is in the immediate escalator area. Wayfinding of Aging Passengers and Persons with Disabilities ACRP Research Report 177: Enhancing Airport Wayfinding for Aging Passengers and Persons with Disabilities (Harding et al. 2017) provided guidelines on wayfinding for vertical transi- tions. The report stated several associated factors that could adversely influence the wayfinding experience for aging passengers and persons with disabilities. The first factor is orientation. Escalators that involve a switch back, or require a change of direction after reaching the end, can be disorienting. Elevators with front and back doors that open depending on which level is being accessed can also be disorienting. The result of being disoriented is confusion in terms of which way to go. Research studies have noted that over signing is commonly employed to compensate for the complex floor plan layouts in environments such as airports where wayfinding is a chronic problem. Other studies show that increases in plan complexity are directly related to decreases in wayfinding performance. The presence of signs cannot compensate for wayfinding problems that are due to the complexity of a floor plan. However, compensating is exactly what wayfinding in a complex airport environment is expected to do. The second factor is direct line of sight. Vertical transitions that are hidden from the direct line of sight require an additional layer of signage. They also call for one or more additional turns, and each turn

Literature Review 15 requires a certain level of mental effort to reorient oneself afterward as the customer exits the elevator and finds their way back to the primary circulation path. For passengers who are blind or have low vision or cognitive impairments, what seem like minor details can have a significant impact on their ability to successfully negotiate these vertical transitions. ACRP Report 177 is consistent with other references but also provided additional guidelines. The following guidelines can help airports improve wayfinding at vertical transitions for older adults and people with disabilities: • Locate elevators and lifts in the same area as stairs and escalators. • Where elevators are not close or in sight of stairs and escalators, passengers need clear directional signage to find the elevator plus wayfinding from the elevator back to the primary path. • For both confirmation as well as safety, detectable floor surface changes (color, texture) should be present at approaches to escalators, moving walkways, and stairs. • As an additional safety measure, escalators that include visual reinforcement of operating direction can help older adults and passengers with cognitive disabilities. These also benefit international passengers who may be used to walking left rather than right or vice versa. • Elevators enclosed in glass or with glass doors provide line of sight from inside the cab, which helps orient passengers as they transfer from one level to another. Glass-enclosed elevators are also easier to identify as a means of vertical egress. (Harding et al. 2017) Advisory Circular 150/5360-12F on Airport Signing and Graphics emphasizes the importance of consistent signage and, in particular, signs within and between airports (Federal Aviation Administration 2013). Wayfinding: Examples from Transit Applications Sydney, Australia In the Sydney, Australia, subway, the elevators were difficult for passengers to locate. As a result, many train passengers carrying bulky items such as baggage and strollers often used the escalators, resulting in injury incidents. To identify strategies for reducing the risk, a consulting company developed a specific survey methodology based on the layout of each station and using the best-practice safety principles, designed a wayfinding signage strategy for the station. The new wayfinding signage strategy for Sydney trains was implemented in June 2017. Figure 2-1 shows examples of floor signage that was used in the study by Alan Stewart (Stewart 2017). Note that in Australia, “lift” refers to an elevator. There are no results in the published study that suggest the level of effectiveness of the floor signage. Figure 2-1. Signage on the floor at the entrance to the escalator (Courtesy of Alan Stewart).

16 Escalator Falls London, United Kingdom The London Underground conducted a project to address escalator passenger safety. The project, titled Escalator Passenger Safety Strategy, developed a set of initiatives to encourage better passenger behavior on escalators (Safety, Accessibility and Sustainability Panel 2016). Four key areas developed by the project were: (a) Hold the handrail, (b) Walk/stand safely, (c) Be aware of the step/landing interface, and (d) Where possible, use lifts (elevators) when mobility impaired. The project included twelve initiatives that are listed below. These are included, as airports may be considering similar treatments. Some of the treatments are industry standards, but others are new and were untried before the trials. The results of the trial are also included. (1) Passenger Positional Guides: Bi-directional footprints intended to guide passengers in their safe foot positioning whilst riding on escalators; (2) Step Edge Painting: Industry standard painting of step edges to highlight safe area to stand upon; (3) Step Riser Messaging: Safety messages stenciled on the black step risers; (4) Red Lexan Combs: Red escalator combs manufactured from Lexan polycarbonate, highlighting the interface between the moving step band and the static landing; (5) Under Step Lighting: White light shining up through the gaps between steps at the top and bottom landing to highlight changing geometry of the step in the transition between the landing and the incline and nearing the end of the moving stepway; (6) Top Comb Lighting: Lighting element installed in the balustrade at foot level directly over the comb to highlight transition from landing to step band to stationary landing; (7) LCD Screens in Pattresses ‘e-Toblerone’: High definition bi-directional screens displaying safety messages mounted inside Pattresses on the balustrade between escalators; Pattress or ‘pattress’ box is the container for the space behind electrical fittings such as power outlet sockets, light switches, or electrical fixtures; (8) Embedded Handrail Signage: Safety messages permanently embedded in the surface of the handrail; (9) Virtual Assistant Projector ‘Hologram’: Mobile ‘Virtual Assistant’ silhouette projector unit to impart safety messages installed near escalators; (10) Directional Speakers / PA messaging: Directional speakers at top and bottom of escalator, giving position specific messages; (11) Escalator Floor Vinyls: Temporary floor signage to encourage people to take caution when using an escalator and hold the handrail; and (12) Lift Floor Vinyls: Temporary floor signage to enhance awareness of station lift locations and encourage customers to use the lift instead of an escalator if mobility impaired. The results from a relatively small trial were as follows: (i) Passenger Positional Guides (blue footprints) – accidents reduced by 27 percent, customer changed (in desired way) by 21 percent; (ii) Step riser messages – customer behaviors changed (in desired way) by 13 percent; (iii) Red Lexan combs – accidents reduced by 36 percent, customer behaviors changed (in desired way) by 15.9 percent; (iv) E-toblerones – customer behaviors changed (in desired way) by 11 percent (note that these were dropped due to the high cost); (v) Messages embedded in handrails – accidents reduced by 24 percent, customer behaviors changed (in desired way) by 17.4 percent; (vi) Hologram message – accidents reduced by 13 percent, customer behaviors changed (in desired way) by 19.9 percent; and (vii) Lift floor vinyls proved semi-effective. The lift floor vinyls tested at Waterloo (from Wide Aisle Gate to lift) proved more effective. Table 2-1 is the summary of results from the London Test. The report noted that directional speakers and public address messages were expected to encourage safe behaviors but were unsuccessful because of operational and installation issues.

Literature Review 17 In the 13 stations in which the initiatives were installed, the overall accident rate decreased by 3%. Considering the initiatives were only installed on 15% of the escalators, this is a seen as a significant drop (Harley 2016). Signage Signage on and near escalators has been a topic of discussion at the standards organizations and among risk management professionals. ASME A17.1-2010/CSA B.44-10 (Section 6.1.6.9), specifies that no “additional signage” shall be permitted within the “safety zone” of the escalator. Similar language can be found in Section 6.2.6.8.2 pertaining to moving walkways. The same paragraph goes on to define the safety zone as an area that extends 118 in. (3 m) horizontally outward from the newel and cautions that additional signage should not impede traffic flow. ASME A17.3–2011 only addresses mandatory caution signs and contains no language regarding additional signage. Various inter- pretations of the “additional signage” wording have in the past led to acceptance of handrail signage in some jurisdictions and refusal in others. The benefits of simple motion indicators on handrails have been widely known for decades; they provide better visual cues of speed and direction of travel for escalator passengers, especially for children and the elderly. With today’s evolved print technology it is now possible to provide handrail motion indicators in full-color and in high-resolution, resulting in opportunities to convey safety, directional, or other information to the riding public in a tactile and interactive way. Escalator signage does need controls so that advertising on handrails does not distract from safety signage. In a world where we are bombarded with distractions handrail signs and graphics direct passenger focus to the escalator; improving the frequency of handrail holding and of natural steps both on and off the escalator. (Bothwell 2013) Table 2-1. Results from the London Test. Initiative Statistical Analysis (Accident Reduction >10%) (%) Final Customer Behavior (%) Staff Survey Technical Review Overall Effective Decision Passenger Positional Guides (Blue Footprints) 27 21 Neutral Pass Yes Step Edge Painting –29 2 Negative Fail No Step Riser Messaging –20 13 Positive Pass Yes Red Lexan Combs 36 15.9 Positive Pass Yes Under Step Lighting 0 0.08 Negative Pass No Top Comb Lighting 0 2.10 Negative Pass No e-Toblerones –21 11.20 Positive Pass Yes Embedded Handrail Signs 23.80 17.40 Positive Pass Yes Hologram 13.10 19.9 Positive Pass Yes Speakers/PA Nil Nil Nil Fail No Escalator Floor Vinyls –9 7.60 Negative Pass No Lift Floor Vinyls 22 1.10 Positive Pass Yes Source: Harley 2016. Note: See Appendix A for definition of vinyls.

18 Escalator Falls Congestion ASME A17.1 (Section 6.1.3.6.4) defines the absolute minimum length of clear area at the entry and exit zones of escalators as twice the distance between the centerlines of the handrails. If multiple escalators are operating in a serial configuration, each escalator needs its own inde- pendent safety zone. Further, the provision of a suitable queuing area at the entrance as well as an adequate safety zone at the exit end of the escalator must provide for sufficient space for the composite flows of all pedestrians moving through the area without hindering the movement to and from the escalator. In the review of the airport and MTH references, several incident data reviews cited passenger congestion, particularly congestion resulting from surges, as a causal factor. The survey of airports summarized in Chapter 3 indicated that staff and volunteer ambassadors are deployed to manage passenger congestion. Operations Video Coverage of Escalators All survey respondents indicated that they use video cameras at escalators entrances and exits. Most of the respondents indicated that they use the videos as part of the risk management for claims purposes for the airport. However, airport cameras are not always positioned or directed adequately toward escalators (Griffin 2008). Audio Messages Audio messages provided through speakers directly on the escalator instruct escalator riders to face forward, hold handrails, and stand in the center of the step. Some airports have installed similar audio messages within the traditional paging systems (Griffin 2008). Edited version of audio message (Griffin 2008): Attention please: For your safety and convenience, elevators are located in public areas. If you are a person with special needs, require a cane or walker, and use a wheelchair or any type of mobility devices, we ask that you use the elevators. For persons with small children, strollers, carriers, oversized baggage, and wheeled baggage carts, we also request that you use elevators. For you and your family’s safety, children should never ride escalators unsupervised. Please use extreme caution when wearing soft-soled shoes, flip-flops, and rubber boots and avoid the sides and edges of the escalator steps to avoid getting caught in the moving parts of the escalators. When riding the escalator, please step on and off promptly, step onto the center of the step tread, face forward, hold the handrails, keep loose clothing clear of the sides, do not rest handbags or any other object on the handrail, and pay close attention. Thank you for your attention to this important message. (Griffin 2008) Outreach and Training Public Service Announcements Risk management professionals discussed the use of public service messages. The literature review and survey found very few implementations of official programs targeting escalator safety. The Elevator Escalator Safety Foundation (EESF) developed a public-service education program. The EESF is the leading resource for educational programs that teach children and adults how to ride elevators, escalators, and moving walkways safely. There are three programs

Literature Review 19 targeting children, college-age adults, and older adults, respectively, which are relevant for airports (https://www.eesf.org). Training Risk management professionals have suggested that airport staff and tenants who work or operate near escalators should receive standardized training in escalator safety. Training should focus on how to approach people who may need assistance, how to locate and operate the emer- gency stop button(s), what to do in case of an emergency, and, in the event of an emergency, what information should be provided to investigators. Airport Volunteers and Ambassadors All airports that responded to the survey indicated that an airport had volunteers or ambas- sadors who provided information, wayfinding, or congestion management assistance to passengers. Standardized training should also be available to airport volunteers who provide information, hospitality, and wayfinding assistance. Baggage Check-In and Baggage Claim Risk management data indicate that escalators located before baggage check-in areas or beyond baggage claim areas may have more incidents because passengers are carrying baggage. One solution may be remote baggage check-in and drop-off. In North America, several airports have implemented or are considering remote and off-airport baggage drop-off or check-in. McCarran International Airport (LAS) in Las Vegas introduced off-airport baggage drop-off in May 2006. Travelers can drop their bags off at one of five remote locations, including three hotels, a convention center, and a car rental facility. From there, staff use a secure protocol to transport pre-checked bags to McCarran (Airport Technology 2017). There have been no reported studies on the relationship of off-airport baggage drop-off and escalator falls. Orlando International Airport (MCO) has built a remote baggage handling facility. The air- port and air carriers have contracted with a third-party baggage-handling company to provide options for remote baggage check-in for decades. Bag check-in points are located in a variety of venues, including hotels and rental car areas. Tampa International Airport (TPA) recently opened a remote rental car center that permits passengers to drop off their baggage before using the train to access the terminal. When Tampa Airport’s state-of-the-art Rental Car Center opened on the 14 February 2018, the air- port also debuted an innovative common use remote bag check–the first of its kind in a North American airport. The service allows passengers aboard multiple airlines to print their boarding passes, tag their luggage and drop it off at the same location–before ever stepping foot inside the airport’s main terminal. Tampa Airport (TPA) saw this remote bag check system, which comes at no additional cost to passengers, as an important customer service enhancement and a way to accommodate its rapid passenger growth while maintaining high standards for customer care. Beyond easing passenger travel, the system helps to reduce congestion on our airport’s trains, in the main terminal building and, importantly, at the check-in counters. (Rhodes 2019) Suggested Effective Practices The following summarizes the effective practices from the literature review for escalators: Human factors play a large role in escalator capacity, because the boarding process is the primary determiner of capacity; studies show a wide range of capacity values, from 30 people

20 Escalator Falls per minute (ppm) up to 100 ppm. Based on common practice among airport terminal plan- ners, design capacities typically are estimated at 50 ppm for down escalators and 60 ppm for up escalators if location-specific data are not available. Safe design provisions must include sufficient space for passengers entering and exiting the escalator. This is especially important for escalators located in series. To ease the transition, escalators should have at least three flat steps at both entrance and exit landings, and escalator speeds may be reduced to make entry to and exit from the escalator easier. One airport with a newly renovated terminal is operating the escalators at 90 fpm and has the three flat steps at entrance and exit. Anecdotal information from the airport indicated a reduction in escalator incidents. Multiple references suggest that escalators located before baggage check-in and beyond baggage claim should have additional step width and assume that passengers on average have more than 1.5 bags per person. Clear signage and wayfinding systems are needed to encourage families with children and older passengers to use the elevator. ACRP Research Report 177 (Harding et al. 2017) provided guidelines on wayfinding for vertical transitions.

Next: Chapter 3 - Survey of Current Practices that Contribute to Escalator Safety »
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Escalator falls are a significant concern for risk management staff at airports and in mass transit systems. The major differences between the airport and transit environments are the amount of baggage carried onto the escalator and the level of unfamiliarity of people with the escalator environment in airports.

The TRB Airport Cooperative Research Program's ACRP Synthesis 109: Escalator Falls identifies and describes methods to mitigate risks associated with escalator usage.

Risk management professionals from both the airport and transit environments have expressed interest in developing common reporting schemes and more robust data analysis to identify common causes of escalator falls.

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