The Effects of Interactive Stairways
on User Behavior and Safety
Karen KIMa,1 and Edward STEINFELDa
aCenter for Inclusive Design and Environmental Access, School of Architecture and
Planning, University at Buffalo, SUNY, Buffalo, NY, USA
Abstract. The social context for sta irway d esign in mu lti -stor y buildi ngs is
changing. At one time, stairways were viewed primarily as a means of egress in an
emergency, and elevators or escalator s were the pri mary method o f verti cal
circulation with the exception of monumental “feature” stairways. Today, the
emphasis is changing to promote the use of stairways in buildings as opposed to
use of elevators due to the health benefits of stair climbing. This is providing an
opportunity for architects and building owners to experiment with innovative
designs. One interesting innovation i s the “intera ctive stairway.” Little i s known
about the impact of these interventions on the rate of stair accidents. The purpose
of this study was to assess the safety of interactive stairway designs by comparing
the user's behavior and the incidence of unsafe stair use on two interactive
stairways with a stairway made of conventional material. A checklist for recording
observations of stair users was developed. Observations were conducted in two
museum buildings with interactive stairways and in one university building with a
conventional stairway. Safety-related behaviors and incidents on the interactive
stairwa ys (CM and SM) and the conventional stairway (SU) were do cumented an d
compared. On the interactive stairways, more stair users glanced down at the
treads (CM: 90%, SM: 81% vs. SU: 53%); fewer stair users diverted their gaze
away from the stairs (CM: 22%, SM: 32% vs. SU: 66%); and handrail use was
higher (CM: 40%, SM: 33% vs. SU: 28%). Incident rates were similar across the
stairways (CM: 2.2%, SM: 2.2%, SU: 2.6%). The research suggests that
interactivity can improve stair safety if used appropriately.
Keywords. stair safety, stairway design, interactivity, behavior, universal design,
assessment, obser vationa l study, visual attention.
Stairways are one of the most dangerous parts of the built environment. In a flight of
stairs, each step is a physical obstacle that can interfere with foot clearance and cause a
person to lose balance and fall. The risk is exacerbated by flaws in the design and
construction of stairways [1,2], such as non-uniformity of risers and treads, which often
become the subject of litigation . Moreover, users often do not perceive stairways as
being dangerous unless stair defects are visibly noticeable . In the U.S., stair-related
injuries result in 1,900 deaths  and 1.3 million hospitalizations per year . The risk
estimate is one hospital emergency room visit for every 1,766,000 flights of stairs
climbed . It is also estimated that the annual cost of stairway injuries is 100 billion
dollars in medical and litigation expenses, which is significantly higher than the cost of
1 Corresponding Author: E-mail: firstname.lastname@example.org
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building or improving existing stairways . The statistics suggest research needs for
assessing current practices and knowledge gaps for design of stairways.
Since the advent of elevators, stairways have been hidden in multi-story buildings
with less than desirable qualities, often as a result of being overlooked in the design
process. In recent years, however, there has been growing interest in the role of
stairways in promoting health and active living, particularly in part to reduce obesity
rates in the U.S. [8-10]. The health benefits of stair climbing include improved weight
control, cholesterol levels, lower-limb strength, and cardiovascular fitness [11,12]. In
2013, New York City Mayor Michael Bloomberg issued an executive order to promote
the use of stairways over elevators in new and renovated City buildings .
Accordingly, architects should design highly visible, easy to access, and attractive
stairways . “Interactive stairways” are one thread of activity related to this new
emphasis in design practice. While interest is growing in stair use on both architectural
and policy levels, much less emphasis is being placed on stair safety. For example,
studies have examined the effectiveness of features such as signs, artwork, and music
to increase stair use [11,15,16], but, to our knowledge, no studies have attempted to
assess the impact of these interventions on user safety. These studies would be
warranted simply because a higher frequency of stair use, for any reason, increases the
exposure to risks of falling. But, interactive stairways could cause distraction from the
stair climbing task and alterations in gait while traversing the stairway.
Compared with other interventions, interactive features have shown a significantly
higher impact on stair use and thus greater promise for stairway design as a means to
encourage physical activity . In this study, we consider interactive features such as
sound effects, embedded LED, and technologies that affect the entire stairway as
opposed to individual elements such as interactive art hanging along stairway walls or
attempts to turn the entire stairway into an artwork with paint, sculpture or stair
configuration. These features can change the purpose or the "imageability" of stairways
in buildings by allowing users to engage in stair climbing tasks while feeling as though
they are having an influence on the built environment [16,17]. Moreover, interactive
stairways are able to detect movement on the stairs through sensor technology which
allow users to sense their own movements as feedback is triggered. Perhaps the best
known example of this type of stairway was the "Piano Stairs" at the Odenplan subway
station in Stockholm, which was part of Volkswagen's "The Fun Theory" campaign in
2009. This subway stairway, located next to an escalator, was modified to look like a
piano keyboard and play musical sounds when users ascended and descended. The goal
was to increase stair use by making the stairway fun to use. A 66% increase in stair use
was reported .
This study investigated the effects of interactive stairways on user behavior and
safety by comparing behaviors and incidents on these stairways with a conventional
stairway design. In the U.S., interactive stairways are gaining popularity, especially in
museums as technology exhibits. This presented some opportunities to learn more
about their impact. Our research focused on two issues – visual attention and use of
safety features. First, since stair safety is largely affected by visual attention [1,19,20],
any distractions caused by the interactive system could reduce gaze fixation on the
stairs, and thus increase the risk of tripping, slipping or falling. However, since stair
users are likely to exercise more caution in the presence of known distractions [1,2],
interactivity could also increase visual attention to the stair use task as a compensatory
behavior, mitigating any negative impact on safety. Second, interactive stairways
motivate people to use the stairs in unconventional ways. For example, sounds effects
K. Kim and E. Steinfeld / The Effects of Interactive Stairways on User Behavior and Safety158
that are triggered by movements often cause people to run, jump, skip, and even dance
on the steps. To maintain safety, users may rely more on safety features such as
handrails, slip resistant treads, and visibility of stair tread edges.
The following hypotheses guided the observational research:
xHI: Interactive stairways attract the user’s gaze to the stairway itself.
xH2: There will be less diverted gaze to the surroundings.
xH3: There will be more handrail use on interactive stairways.
The University Institutional Review Board determined that our research did not meet
the definition of human subjects. We did not gain any personal information about
people through intervention or interaction therefore no IRB approval was needed for
1.3. Feasibility Test
Video recording was chosen as the study method as recordings could be replayed
repeatedly for analysis purposes. It has also been used in prior studies of stairway
incidents [1,21,22], although earlier studies were limited due to the technological
constraints and high costs of video recording at the time. Prior to the implementation of
the research, a pilot study was conducted to determine the feasibility of using video
recording to collect data, during which the observer became familiar with recognizing
stair behaviors and pr ecipitating factor s for stair incidents.
1.4. Site Selection
Two interactive stairways, one at the Children's Museum of Pittsburgh (CM) and one at
the Science Museum in Boston (SM), were selected as the sites for observations (see
Figure 1). One other public stairway, without interactive features, at the University at
Buffalo Student Union (SU) was identified as the comparison site.
The Children's Museum stairway (CM) was equipped with sensor stair pads made
of vinyl composition tile in green color that activated sounds of children's voices from
speakers when pressure was applied to the surface. The stair pad system was installed
only on one side of the stairway, for the right-side ascending path, and did not stretch
across the entire stair width. This stairway had sixteen risers per flight, two flights of
stairs, and handrails for both adults and children in an enclosed space that obscured
most of the surrounding views (see Table 1).
The Science Museum stairway (SM) used invisible light beams to detect stair users
and activate sounds. Detection occurred when users crossed light beams between
photoelectric sensors and reflectors that were located at opposite sides of every step.
The sounds changed in pitch and melody based on the user's patterns of ascending and
K. Kim and E. Steinfeld / The Effects of Interactive Stairways on User Behavior and Safety 159
descending. The CM stairway was longer in length, and narrower, whereas the SM
stairway was more open and wider which allowed more people to use the stairs
simultaneously. The CM stairway had graspable handrails, including one for children,
but the SM stairway handrails were too wide to grasp. The comparison site had views
from the stairs and location prominence, which are conditions similar to those in the
Science Museum. Table 1 summarizes the differences.
Figure 1. Interactive stairways at a Children's Museum (left) and a Science Museum (right).
Table 1. Profile o f the stair ways in the museu m buil dings and t he universi ty building.
Science M useum
Views from the stairs
Tread edge contrast
Only on one side
12 in (305 mm)
≥ 11 in (279 mm)
11 in (279 mm)
5.8 in (149 mm)
6.7 in (171 mm)
8 in (203 mm)
Riser count (top)
Riser count (bottom)
Handrai l width
1.5 in (38 mm)
3.5 in (89 mm)
2.25 in (57 mm)
1.5. Checklist Development
An observation checklist was developed to record information on a stair user (see
Figure 2). The checklist included information about demographics, key safety-related
behaviors (tread gaze, diverted gaze, and handrail use), typical beh aviors (talking,
using electronic devices, and carrying things), and noticeable stair incidents. Stair
incidents included hesitation, losing balance and missteps which, in this study, are
considered "precursors of falls."
Tread gaze, or observed glances at treads, is a key safety-related behavior because
visual scanning of treads is important for depth perception, foot placement [1,19,23]
and postural control [20,23]. Depending on how safe the stairway appears to the user,
tread gaze occurs either frequently or infrequently and can be measured by the number
of gazes per step, e.g. once every seven steps taken . Frequent tread gaze was
K. Kim and E. Steinfeld / The Effects of Interactive Stairways on User Behavior and Safety160
defined as glancing at the treads three or more times throughout an entire flight of stairs,
and infrequent tread gaze as frequencies of two or less times. Glances were measured
each time the user's head turned downwards toward treads. For safe negotiation of long
stairway runs, one glance may be necessary at the beginning, middle, and end phases of
stair walking, or the transitions and middle steps of a flight of stairs . Thus, three
glances were used as a threshold of safe attention to the stair climbing task.
Diverted gaze and handrail use were included as behaviors to observe as these
variables could indicate several aspects of stair use including user comfort, distraction,
and caution on the stairs [1,2].
Figure 2. Observation checklist.
1 2 3 4 5 6 7 8 9
Child (ages 1-14)
Young Adult (ages 15-24)
Middle-Aged Adult (a ges 25-64)
Older Adult (ages 65+)
Frequent tread gaze (3 or more glances at the treads)
Infrequent tread gaze (2 or less glances at the treads)
Handrai l use
Using el ectron ic devi ces
Loss of balance
1.6. Collection and Recording of Data
Two hours of video were used to analyze stair users in descent only, due to limitations
of video angles that make it difficult to observe people ascending. For example, at
points near the front and bottom of stairs, it is not possible to clearly see the ascending
user's head/eye movements since their backs are turned. Video recording was
conducted by the first author at the Children's Museum (CM) on a Friday and at the
Science Museum (SM) on a Sunday between 12:00 and 14:00. Observations were
collected at the comparison site (SU) on a Tuesday and Thursday in the late afternoon.
At each site, the video recorder was positioned to capture stair users from head to foot
within 20 feet of the stairway. To be unobtrusive, the observer either sat with the
recording device in a seating area or sat in a seating area a few feet away from the
video recorder. Data from the video recordings were coded and analyzed using a
computer based video processing program. Stair incidents were recorded on the
checklist, extracted from the video data, and time-stamped so that examples of unsafe
stair use could be located easily for further analysis.
K. Kim and E. Steinfeld / The Effects of Interactive Stairways on User Behavior and Safety 161
A total of 92 stair users in the Children's Museum (CM), 502 stair users in the Science
Museum (SM), and 453 stair users in the Student Union (SU) were observed. The
incidence of hesitation, misstep, and loss of balance as a percent of all stair descent was
similar across all three samples (CM: 2.2%, SM: 2.2% vs. SU: 2.6%) (see Table 2).
Table 2. Cross-site comparison of the incidence of unsafe stair use.
Science M useum
Loss of balance
In the Children's Museum, 4% (4) of the users repeatedly used the stairway. Nearly
23% (21) of the users walked on the sensor stair pads along their left-side descending
path, which is considered the "wrong" side of the stairway. One stair incident (50%)
occurred as a result of intentionally using the interactive feature. In the Science
Museum, 17% (86) of the users repeatedly used the stairway. Twenty-seven percent (3)
of the stair incidents occurred from these repetitive uses. There was no repeated use of
the SU stairway.
Hesitation or sudden disruption in walking movements occurred at a slightly lower
rate in the Science Museum (SM: 0.4% vs. CM: 1.1%, SU: 1.5%) (see Table 2). Loss
of balance rates were virtually the same across the buildings (CM: 1.1%, SM: 1.2%,
SU: 0.8%). Misstep rates were higher in the Science Museum (0.4%) compared to
0.2% in the Student Union; no missteps occurred in the Children's Museum. One fall
(0.2%) was observed in the Science Museum as a result of a child jumping on the stairs.
On the interactive stairways, more stair users glanced down at the interactive steps
than the conventional steps (CM: 90%, SM: 81% vs. SU: 53%) (see Figure 3). Frequent
tread gaze was involved in 100% (2) and 82% (9) of the incidents compared to 42% (5)
on the conventional stairway; in the Student Union, stair incidents were more
associated with infrequent tread gaze (58%). Fewer stair users diverted their gaze away
from the interactive stairways (CM: 22%, SM: 32% vs. SU: 66%) (see Figure 3). When
returning attention to the stairway, users may have a tendency to re-orient themselves
by glancing at the stairs. It was noted that diverted gaze was involved in fewer stair
incidents in the museum buildings, CM: 50% (1), SM: 36% (4), than in the Student
Union (92% or 11).
Handrail use was highest in the Children's Museum and lowest in the Student
Union (CM: 40% vs. SM: 33%, SU: 28%) (see Figure 3). The rate of handrail use in
the conventional stairway supports research findings that handrail use is often minimal
. The results support our hypothesis that stair users would display more
compen satory behavior by looking at the tread more, looking less at the surrounding
environment, and by using the handrail more. The study did not find any significant
patterns among age groups nor in typical user behaviors (talking, using electronic
devices, and carrying things).
K. Kim and E. Steinfeld / The Effects of Interactive Stairways on User Behavior and Safety162
Figure 3. Cr oss-site comparison of key behavior s.
21.7% ■ 32.2%
40.2% ▲ 33.0%
Children's Museum (CM)
N = 92
Science Museum (SM)
N = 502
Student Union (SU)
N = 453
* Percentages are the percent of the total sample of each stairway.
** Stair users exhibited more tha n one behavior.
Cross-site comparison of key behaviors
Tread Gaze Diverted Gaze Handrail use
The incidence rate for hesitation, misstep, and loss of balance were similar across the
stairways. But, users gazed more frequently toward the treads and used the handrails
more frequently on the interactive stairways, demonstrating that the awareness of
potential safety risks leads to compensatory behavior. On the conventional stairway,
stair users tended to focus their visual attention on the surrounding environment rather
than the treads and used the handrail less frequently. When a hazardous condition is not
perceived, users do not take compensatory action. Although we observed greater
incidences of tread gaze and handrail use on the interactive stairways compared to the
conventional stairway, we did not observe differences in altered gait, suggesting that
these behaviors compensated for the distractions the interaction may cause. But, we
also found that tread gaze was involved in most of the incidents on the interactive
stairways. These results suggest that novel events can capture the user’s attention in an
involuntary way to focus attention to a potential danger but, at the same time, distract
attention away from the task at hand. Distraction could be related to the nature of the
stimuli. For example, random and novel noises could be distractions but music more
Among experts, prevailing wisdom is that the most dangerous risks are those that
are not perceivable. This opinion seems to be confirmed by this study. But, at this point
there is not enough data to justify a conclusion that interactivity per se either creates
safety hazards or increases safety. Previous studies demonstrate that people may have
difficult y perceiving certain risks of stairways even though they should be obvious.
Furthermore, the novelty of interactivity could lead to increased vigilance and handrail
use initially that is not sustained as users become accustomed to the interactive features.
K. Kim and E. Steinfeld / The Effects of Interactive Stairways on User Behavior and Safety 163
The deployment of interactive stairways is intended to enhance a museum visitor's
experience. But it is important to learn more about how interactive design strategies
actually affect stair safety behavior especially when adequate safety features, like
graspable handrails, are not present. Interactive features increase exposure to risk. For
example, in the Children's Museum, a misstep occurred when a stair user intentionally
walked on the "wrong" side of the stairway in order to interact with the stairway. In the
Science Museum, 27% of the incidents were a result of repeated use of the interactive
stairway, especially by children. It’s not surprising that interactive features appealed to
children’s curiosity and sense of play so a group of children was easily motivated to
using the stairways. Designers who are exploring digital technologies to enhance the
stair climbing experience should take notice because this puts children at greater risk of
accidents. For example, when retrofitting existing stairways to interactive features,
handrails should be provided to compensate for uncon ventional stair behavior. The
Science Museum currently has ungraspable handrails that are also unreachable to small
Interactive stairways can indeed be more inclusive and engaging environments.
Our observations revealed repeated use of the interactive stairway in the Science
Museum among all age groups, demonstrating their appeal. But, understanding and
applying this technology requires more than just designing attractive stair features. It is
important that these installations do not create potential unsafe conditions. In the
Children's Museum, for example, installation on only half of the stairway enticed stair
users to intentionally walk into opposing traffic in descent. Motion sensors, which do
not directly impact gait, are clearly less intrusive than pads applied to the treads. An
increased public awareness is also necessary to reduce acci dents. For instance, adults
should caution children when using interactive stairways or restrain children from
using interactive stairways when safety hazards are present.
It should be noted that there are interactive stairway designs that could be much
more dangerous than those studied, for example, the use of dynamic LED color
displays and a painting incorporated into stairways create optic effects (see Figure 4)
that can camouflage the edges of the treads. Additional research in this area could be
very beneficial to identify what is dangerous and what is not, but education for museum
administrators is also needed to acquaint them with the potential hazards and how to
suitably protect people from exposure to risk, e.g. use of signs and barriers.
Figure 4. a) Left –a stairway with LED color displays on stair risers, b) Right – a stairway painted as an art
K. Kim and E. Steinfeld / The Effects of Interactive Stairways on User Behavior and Safety164
The study had several limitations. It compared stairways with different
characteristics using only two hours of observations. Longer or more frequent
observation periods could produce different results, although the short observation
period did result in reasonable sample sizes. Studies of stairways that are more
comparable in design would provide more direct comparisons of targeted stair features,
particularly before-and-after comparisons of installations. In addition, a larger sample
would provide more data on the impact of those features on different age groups; this
study did not have enough data for each age group to analyze this relationship.
Although the study was based on naturalistic observations rather than automated
data collection of user behavior such as the use of an eye-tracking device or motion
analysis, the video recording method allowed the observer to track head movements
that were purposefully aimed downwards, which is strongly suggestive of gaze aimed
at the treads. The study demonstrated that the use of video recording for observations
of stair use is an inexpensive and easy to implement method for assessing stairway
design features that are being used in public places without appropriate research
Further studies using this empirical method would add to our knowledge of
contemporary stairway designs and contribute to improving the usability and safety of
stairways for diverse users. Laboratory studies could contribute further toward this
developing knowledge base. In a laboratory, more sophisticated measurement tools like
eye gaze systems, motion analyses, and force plates can be used. Moreover, different
types of interaction can be studied and varied systematically. Laboratory research
would not only increase our knowledge about the issues related to interactive stairway
design but also be useful in testing concepts before they are implemented in public
places. Other contemporary practices, such as open risers, glass stair treads, and
embedded LEDs clearly require similar research attention.
Stair safety can be improved by understanding the impact of stairway design
interventions on the rate of stair incidents. Interactive stairways were assessed by
observing stair users and comparing the incidence of unsafe stair use on two interactive
stairways in museum buildings with a stairway made of conventional materials in a
university building. We identified differences in the behavior of stair users (tread gaze,
diverted gaze, and handrail use) between the stairways. The results indicated that
interactive stairways can be as safe as any other stairway but they do alter stair use
behavior. The research technique used in the study should be used to evaluate more
contemporary stairway design features. An interesting finding from this work is that
interactivity appears to increase vigilance while negotiating a stairway and handrail use.
On the one hand, this may be a result of perceived safety risks that could otherwise be
avoided. But on the other, it suggests that interactivity, in some form, can be used to
increase safe behavior on stairways. The introduction of lighting at stair edges, flashing
lights to bring attention to handrails, sounds that provide feedback on progress along
the stairway or even as a caution to unsafe behavior, all may prove useful as
countermeasures to the inherent risk of stair climbing.
K. Kim and E. Steinfeld / The Effects of Interactive Stairways on User Behavior and Safety 165
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The contents of this report were developed under a grant from the Department of
Education, NIDRR grant number H133E100002. However, those contents do not
necessarily represent the policy of the Department of Education, and you should not
assume endorsement by the Federal Government.
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