PowerPoint presentation using speaker notes; vision and mission statements, 3-4 Strategic Objectives, minimum of 5-6 slides

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Building smart airports: Technology solutions to improve health, enhance experience and increase revenue Received: 11th November, 2021

PIERS MACNAUGHTON VP, Health Strategy,View Inc., USA

Piers MacNaughton SCD is an engineer turned public health advocate, specialising in healthy buildings. He is the Vice President of Health Strategy for View, where he partners with universities to conduct research and provides strategic guidance on product development. His goal is to accelerate the adoption of healthy building practices and technologies through transformative research and active engagement with building professionals. His work focuses on exploring the key drivers of decision making, such as health, productivity and student achievement in the places we live, work, learn and travel through. Dr MacNaughton graduated from Tufts University with a degree in environmental engineering and subsequently from the Harvard T.H. Chan School of Public Health with a master of science and doctor of science in exposure, epidemiology and risk in the Department of Environmental Health.

View, 195 S Milpitas Blvd, Milpitas, CA 95035, USA Tel: 978-886-0315; E-mail: [email protected]

Abstract Modern airports are seeking new ways to differentiate and enhance the travel experience. They have hybridised to become both transportation hubs and shopping centres. Airports now view passengers as their primary customers and are becoming more aware of passenger needs throughout the travel experience. In the wake of the COVID-19 pandemic, airport health and safety is the travelling public’s highest priority. Airports need to invest in technology that addresses health and safety concerns elevates the passenger experience, and provides a substantial return on investment in the long run. Recent surveys show that the most effective technologies are not always the ones airports are employing: environmental sensing, innovative display technology and smart glass that increases access to daylight and views of the outdoors are three such solutions. As these types of solutions become more prevalent, passengers will come to expect an increased level of comfort and convenience out of their travel experience. This paper will focus on two key technologies — smart glass and environmental sensing — that can provide a solution.

Keywords Passengers, retail, innovation, engineering, environmental management, customer service

INTRODUCTION The way airports view passengers has changed. Airports have largely tran sitioned from transportation hubs to destination spots in their own right. The success of this strategy depends on reducing the stressful components

of the airport experience and replacing them with engaging activities for passengers to enjoy. Therefore, airports now view passengers as their primary customers. There is an increasing realisation among airport executives that non-aeronautical revenue can be a

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substantial part of total airport revenue. Not only does improving the services available to travellers drive additional concessions, over time, the reputational and brand improvements position the airport favourably for additional enplane- ments and expansions. It follows that airports are changing how they address passengers’ needs.

At the same time, there has never been a greater need for airports to restore pas- senger confidence, enhance the passenger experience and generate additional reve- nue. The COVID-19 pandemic brought air travel to a halt. Globally, the number of people flying decreased by nearly 95 per cent at the beginning of the pandemic, and the impact on airport revenue was equally unprecedented.1

Throughout 2020, passenger travel was down 60 per cent, amounting to US$391bn in lost revenue for airlines.2

The individual’s personal health, and the health of others, are the travelling public’s two highest priorities in the wake of the COVID-19 pandemic, and the association between infectious dis- ease and air travel will persist beyond the COVID-19 pandemic. With travel serv- ing as a vector for disease, the perception of the risks of travelling far exceed the actual risks of disease transmission during the travel experience. In a recent survey of 970 passengers across the United States, more than 70 per cent said that concern about the airport as a healthy environment is a greater priority than it was before the COVID-19 pandemic.3

In response, according to a recent Airport Council International (ACI) study, 87 per cent of airports say they are looking to incorporate technology that addresses health and safety concerns.4

For example, much has been done to update air filtration systems, including upgrading to filters with higher MERV

(Minimum efficiency reporting value) ratings and even incorporating ultra- violet light to kill airborne pathogens. These investments are useful and go a long way toward creating a healthier airport environment; however, the passenger is unlikely to be aware of these solutions being present and effective. Solutions that are a visible part of the travel expe- rience or that communicate the impact of invisible solutions are necessary to improve passenger confidence.

Airports need to invest in technology that can work triple-time: technology that addresses health concerns, elevates the passenger experience and provides a substantial return on investment in the long run. This paper will focus on two key technologies — smart glass (also known as dynamic glazing) and envi- ronmental sensing — that, combined, provide such a solution.

SMART TECHNOLOGY RESTORES PASSENGER CONFIDENCE Environmental monitoring In April of 2021, I was part of a team that surveyed people’s attitudes toward flying in the wake of the COVID-19 pandemic. Almost two thirds of respondents said they were comfortable returning to air travel — a significant increase over just a year ago when the number was closer to 20 per cent — yet, enticing the remain- ing third back to travel will be much more difficult.5 By restoring confidence in this group of future passengers, air- ports could accelerate their return to travel by up to 8 months.6 If airports are to succeed in this endeavour, their first step should be to understand and address the expectations these travellers have for a post-COVID-19 world. Unfortunately, the strategies that travellers expect air- ports to implement — monitored social

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distancing and regularly cleaned surfaces, for example — are not necessarily the ones that boost confidence. The question then is: What would?

During the survey, 862 people who had travelled through five of the busi- est airports in the United States in the last two years were presented with more than a dozen strategies that airports have either adopted or considered adopting to increase passenger confidence. The travellers were asked to rank these strat- egies on two scales: Would the strategy increase their confidence that an airport is taking steps to ensure their health and safety? And to what extent would the strategies impact their travel experience?

For example, we found that, while surface-cleaning robots would be a novel addition to passengers’ travel experience, they would not boost their confidence. Other strategies — requiring passengers to be fully vaccinated before they can fly and taking their temperature as they enter the airport — had a huge impact on traveller confidence; however, because they place the burden primarily on the passenger, that confidence came at the expense of the travel experience. And some strategies, such as contactless bag checks, do not boost confidence and result in a significant burden for passengers.

The survey uncovered several solutions that can improve passenger confidence without compromising passenger experi- ence. Out of more than a dozen strategies proposed during the survey, 67 per cent of respondents said that 24/7 indoor air quality monitoring would increase their confidence without impacting their travel experience. Importantly, the reaction to environmental sensing was strongest among those who were still uncomfortable returning to air travel. Concerned passengers said they would be twice as likely to sit at a gate with

Indoor Air Quality (IAQ) monitoring than one without it.

IAQ monitoring encompasses a number of health-related factors such as air quality, temperature, humidity, light and sound. Airport managers can lever- age the insights provided by sensor data to make smart decisions to ensure a healthy and comfortable environment. Advance- ments in recent years have made these sensors smaller, quieter and less expen- sive. They can integrate into window frames, walls and ceilings to monitor parameters at the passenger level to accu- rately estimate passenger exposures.

For example, Dallas Fort Worth International Airport (DFW) recently installed these sensors at its new ‘Gate of the Future’, a fundamental rethink of gate design in which the health and experience of passengers take priority, to improve operational excellence and deliver a world-class and unique experi- ence to their travellers.

The benefits of environmental sensing will outlast the COVID-19 pandemic. Scientists increasingly say that we can expect pandemics to occur more fre- quently in the future. So it is important that the strategies airports implement to restore confidence in travellers today be forward-thinking. This is what makes environmental sensing such a strategic investment. More than two-thirds of travellers say they want airports to con- tinue IAQ monitoring post-COVID-19. With this environmental sensing infra- structure in place, airports will be able to maintain confidence in travellers and buffer the economic toll when the next pandemic hits.

Smart glass While airports must implement techno- logies that relieve the acute strain on air

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travel caused by the COVID-19 pan- demic, it is important that they also take steps to solve the chronic problem of unhealthy building design. A growing body of research shows that one of the key drivers of passenger satisfaction is access to daylight and views of the outdoors. More than any other airport design element, daylight and views drive passenger health and comfort. To understand why this is the case, it is important to first exam- ine our understanding of daylight and its impact on human wellbeing.

For decades, scientists have known that the amount of natural light we receive is a critical determinant of health. Studies have shown that increased daylight and views of the outdoors can regulate cir- cadian rhythm,7 lower blood pressure8

and even positively impact our ability to learn.9 This is because, as a species, humans evolved in daylight.

For the bulk of human history, we have been an outdoors species. We evolved to thrive in the natural environ- ments around us. Fast forward to today: Modern society has erected walls between humans and the outdoors. Americans now spend more than 90 per cent of their time indoors.10 We have replaced the Sun’s natural light with artificial light- ing and fresh air with recirculated air. These environmental changes can result in sick building syndrome, an umbrella condition for the health effects arising from poor indoor air quality, inadequate daylight and other indoor environmental exposures.11

This is one reason why modern build- ings, including airports, tend to utilise as much glass as possible. Glass provides shelter and protection, but we can still see through it and connect with the outdoors. Today, architects are designing airports with floor-to-ceiling glass facades that let in abundant natural light and offer

sweeping views of runways, cityscapes and the surrounding environment.

There is encouraging evidence that the increased daylight and views provided by glass has a positive impact on human health and wellbeing. Research going back 150 years has shown that daylight can disinfect bacteria, viruses and fungi. The Pakpour Laboratory at the Uni- versity of British Columbia found that daylight passing through smart windows nearly eliminated bacteria from surfaces while traditional windows with blinds had similar bacteria levels as a dark space. Smart windows, even in their darkest tint state where they are blocking 99.9 per cent of UV light that can be harmful to skin health, bring in more higher energy, shorter wavelength light that has the power to disinfect. With airports being major hubs where millions of passengers interact, the ability to sterilize surfaces with daylight can help reduce the risk of disease transmission during travel.12

In additional to infectious disease, smart windows can improve other dimensions of health. Research by Dr Mohamed Boubekri, a professor in the school of architecture at the University of Illinois at Urbana Champaign, shows that people who work in offices with plenty of natural light sleep 46 minutes more each night than employees who work in offices with windows or access to daylight.13

However, not all windows provide the same level of health benefits. For exam- ple, traditional low-emissivity, or low-E, glass windows, come with their own technological problems. While conven- tional low-E glass windows let in natural light, they also amplify the Sun’s energy like a magnifying glass, leading to sig- nificant glare and heat from the rays of the Sun. Passengers can only spend so much time near them before they start

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to feel uncomfortable.14 So far, we’ve compensated for these visual and thermal discomforts by hanging blinds, shades or curtains. Apart from being expensive to maintain, blinds block daylight and views of the outdoors, defeating the entire pur- pose of windows in the first place.

Smart glass, or dynamic glazing, reduces glare and unwanted heat within a terminal and provides a comfort- able environment for passengers. This high-performance technology is based on a cutting-edge, proprietary electro- chromic coating made up of thin layers of metal oxide. Running a low-voltage current through this layer results in a phase change, leading to greater opacity of the glass. The darker the tint, the more solar radiation and glare the windows deflect, ranging down to 1 per cent light transmission and 9 per cent solar heat gain coefficient.

In a recent study, Boubekri and Dr Usha Satish, a cognitive scientist at SUNY Upstate Medical University, mea- sured the sleep and cognitive function of participants in two controlled office set- tings: one with traditional glass windows outfitted with blinds; another with smart windows that maximised daylight while maintaining a view to the outdoors.15

Other factors, such as furniture layout, air quality and temperature were held con- stant throughout the study.

The participants spent one week in each environment. Boubekri and Satish measured sleep duration throughout the study with precision sleep trackers — the same wrist-watch-sized devices used in studies by the Center for Disease Control and National Institute of Health. At the end of the first day and last day of each work week, they tested the participants’ cognitive function using a test designed to measure real-world decision-making performance.

Boubekri and Satish found that the participants working in the office with smart windows slept 37 minutes longer compared to when they worked in the office with blinds. Not surprisingly, better sleep correlated with 42 per cent higher scores in cognitive tests taken at the end of the work week. Symptoms of sick building syndrome also decreased: the participants were also 48 per cent less likely to report eyestrain and 77 per cent less likely to report feeling depressed in the room with smart glass.

SMART TECHNOLOGY ENHANCES THE PASSENGER EXPERIENCE Enhancing passenger experience at Dallas Fort Worth International Airport and Charlotte Douglas International Airport As major airports invest in upgrading facilities to provide passengers with a healthier and more pleasant travel expe- rience, the question arises: What design features or amenities in the airport most influence passengers? The current thinking is that amenities such as elec- trical outlets and concessions are the key drivers of passenger satisfaction. But two recent studies suggest that daylight plays an important role in how passen- gers rate their overall gate experience. Passengers say access to light and views is their second-highest seating priority, outweighing both electrical outlets and bathrooms in importance. This places daylight and views in direct compari- son to other amenities often installed to enhance the passenger experience.

In the fall of 2017, Dallas Fort Worth International Airport (DFW) replaced the existing low-E glass at two loca- tions in Terminal A — Gate A28 and the Twisted Root, a bar and restaurant

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— with electrochromic smart glass, which intelligently optimises daylight and views of the outdoors. To better understand the importance of daylight and views in the airport setting on pas- senger comfort, Dr Alan Hedge of Cornell University conducted a compar- ative survey of 503 passengers at DFW, half of whom were seated at the gate with newly installed smart glass windows and half of whom were seated at a gate with conventional low-E windows (A25).16

The survey took place over the course of five weeks during the hours when Sun penetration was greatest.

Video footage collected at both gates found that passengers at the gate with low-E glass frequently used their bodies to shield their electronic devices, such as tablets, laptops and phones, from glare. A few even wore sunglasses. Alter- natively, at the gate with smart glass, passengers comfortably used their per- sonal electronic devices, even in the seats nearest the windows. Ultimately, passengers at the gate with smart glass stayed seated near the windows 83 per cent longer than they did in the gate with low-E glass.

In addition to reducing glare, Dr Hedge found that smart glass also reduced the uncomfortably warm tem- peratures associated with sick building syndrome — particularly in seats nearest the windows. He found that the surface temperature of seats and carpet in the gate with low-E glass was up to 90 degrees Fahrenheit, while surface temperatures in the gate with smart glass were 10 to 15 degrees cooler, resulting in a much more comfortable thermal environment.

In 2019, Dr Hedge conducted a sub- sequent passenger experience study at Charlotte Douglas International Air- port (CLT) — this time at the concourse level.17 He surveyed 573 passengers at

CLT, half of whom were travelling through a concourse outfitted with low-E glass windows (Concourse E) and half of whom were travelling through a concourse that had recently been reno- vated with smart glass (Concourse A). Both concourses have a south-facing orientation, allowing for a one-to-one comparison of passengers under similar solar exposure.

Just as in the DFW study, passengers in the concourse with smart windows were significantly more comfortable while waiting at their gates: 75 per cent reported daylight conditions to be ‘very comfortable’, compared to just 63 per cent of passengers in the concourse with low-E glass. And once again, the study found that surface temperatures in the gates with smart windows were approxi- mately 15 degrees Fahrenheit cooler than in the concourse with low-E glass despite the window area being over 4 times greater.

The DFW and CLT studies demon- strate the connection between increased daylight and views with an increase in passenger experience. The upshot: Improving the physical environment presents the single best opportunity for airports to provide passengers with a healthier, more comfortable and less stressful travel experience.

Smart glass and IAQ work best together Because each pane of smart glass has power and connectivity, it is possi- ble to enhance them with additional software applications. One recent inno- vation allows airport executives to transform smart windows into trans- parent, ultra-high-definition digital canvases, which can be used to com- municate and entertain passengers by

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displaying meaningful information right onto the glass. This Internet of Things application is already being installed in buildings across the United States, includ- ing DFW’s new ‘Gate of the Future’.

Figure 1 In addition to reducing visual discomfort by minimizing harsh sun penetration, electrochromic glass technology also reduces solar heat gain. The study at CLT found that surface temperatures in the gates with Smart Windows were approximately 15˚F (9˚C) cooler, a factor that improves passenger thermal comfort

Such an application has immediate practical benefits. The COVID-19 pan- demic presented airport managers with a challenge: Maintaining social distancing requirements to keep travellers comfort- able required more space, but they could not make their gates any larger. Modern airports are designed with large glass facades. The ability to transform smart windows into transparent displays would allow airport managers to leverage this abundant real estate to communicate important information — such as real- time environmental quality data, flight

updates and advertisements — and reduce the need for bulky displays that take up valuable floor space.

The futuristic look and feel of a trans- parent display is also exciting to passengers. During the recent survey of people’s attitudes toward flying in the wake of the COVID-19 pandemic, researchers showed the 862 respondents a series of renderings that illustrated how transpar- ent displays would look at a gate compared to traditional displays, such as televi- sion monitors. We found that passengers tended to prefer the transparent display technology — they were 66 per cent more likely to choose a gate that had transparent displays than one without them.

On their own, environmental sens- ing and smart glass technology improve

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passengers’ confidence and experience, but combined, they work double time. Passengers were 45 per cent more likely to give a five-star rating for a gate that has both environmental monitoring and communicates the results of that moni- toring with a transparent display relative to gates that had neither.

SMART TECHNOLOGY INCREASES REVENUE As discussed above, the best technological solutions will be holistic and impact mul- tiple goals at the same time; not only will they elevate the passenger experience and address health and safety concerns, but they will also increase revenue. During his study of 503 passengers at DFW, Dr Hedge found that the benefits of air- port design features can extend beyond the passenger and improve the airport’s commercial performance. An analysis of concession revenue at the Twisted Root restaurant revealed an average 102 per cent year-over-year increase in revenue over the six months after the installation of smart glass (see Table 1).18

Dr Hedge’s research suggests that improving the gate experience through smart technology can increase passenger satisfaction, ultimately leading to higher revenues. The potential ramifications of this finding are significant.

During his study of 573 passengers at CLT, Dr Hedge found that passengers in the concourse with smart windows were 68 per cent more likely to be very sat- isfied with their overall gate experience — a 9 per cent increase in passenger sat- isfaction. According to a study by ACI, for every 1 per cent increase in passenger satisfaction, airports can expect to see a 1.5 per cent increase in non-aeronautical spending.19 The ACI report looks at satisfaction across the whole travel

experience, even though non-aeronautical spending is limited to the gate area. Gate satisfaction likely has an even stronger association with concession revenue as satisfaction with check-in and security has little impact on concession spending. That being said, using the ACI rela- tionship the 9 per cent increase in gate satisfaction can conservatively be esti- mated to lead to a 13 per cent increase in non-aeronautical spending in the case of CLT.

Table 1 Year-over-year revenue increase at DFW’s Twisted Root restaurant following renovation with Smart Windows.20

Year-over-Year Sales

Oct 2017 – Oct 2016 + 89%

Nov 2017 – Nov 2016 + 108%

Dec 2017 – Dec 2016 + 101%

Jan 2018 – Jan 2017 + 107%

Feb 2018 – Feb 2017 + 83%

Mar 2018 – Mar 2017 + 128%

Average over six months + 102%

When Dr Hedge translated his find- ings on passenger satisfaction at CLT to a score on a one to five-star rating scale (from very unsatisfied to very satisfied), the average score among responses col- lected in the concourse with low-E glass was 4.05. In contrast, the average score among responses collected in the con- course with smart windows was 4.41.

The five-star rating is the airport’s most powerful tool for advertising the comfort and convenience travellers can expect. As such, airports are doing every- thing they can to nudge their ratings higher and higher — an often mystify- ing task. An airport can offer expansive dining options, it can house lavish air- line lounges, and it can provide all the electrical outlets and free wi-fi passen- gers could desire — all of these are vital given today’s exacting travelling public, but none of them strike at the foundation

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of the passenger experience. An airport’s ability to employ the right technologi- cal solutions will be crucial in a future where passengers are the airport’s pri- mary customers.

An airport that responds to the COVID-19 pandemic by employing technologies that put the health and safety of passengers at the centre will restore confidence sooner and hedge against any future uncertainties in air travel. Of course, this will require a research- driven approach to airport design and a few strategic investments, but the reward will be an airport that addresses health and safety concerns, elevates the travel experience and increases revenue.

KEYS FOR IMPLEMENTING TECHNOLOGY TO ENHANCE PASSENGER EXPERIENCE ● Engage all stakeholders in the selection

process to ensure priorities are met ● Work closely with building and termi-

nal teams throughout the installation and commissioning process

● Track passenger experience on a quarterly basis to evaluate impact of interventions

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(11) Joshi, S., (2008), ‘The sick building syndrome’, Indian Journal of Occupational & Environmental Medicine, 12, 2, 61-64.

(12) Lam M., Vojnits K., Zhao M., MacNaughton P., Pakpour S., (2022), ‘The effect of indoor daylight spectrum and intensity on viability of indoor pathogens on different surface materials’, available at https://www. biorxiv.org/content/10.1101/2022.01.14. 476401v1

(13) Boubekri, M., Cheung, I., Reid, K., Wang, C.

and Zee, P., (2014), ‘Impact of windows and daylight exposure on overall health and sleep quality of office workers: A case-control pilot study’, Journal of Clinical Sleep and Medicine, 10, 6, 603-611.

(14) Hedge, A., Nou, D. and Horton, R., (2018), ‘Electrochromic Glass Enhances the Passenger Experience in Airports’, Ergonomics International Journal, 2, 6, 1-8.

(15) Boubekri, M., Lee, J., MacNaughton, P., Woo, M., Schuyler, L., Tinianov, B. and Satish, U., (2020), ‘The impact of optimized daylight and views on the sleep duration and cognitive performance of office workers’, International Journal of Environmental Research and Public Health, 17, 9, 3219.

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