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Signs of crime prevention through environmental design (CPTED) can be found all around Washington, D.C., landmarks. A combination of security, safety, and accessibility concerns led to the construction of the Capitol Visitor Center—an underground entryway into the U.S. Capitol Building. The design of this space, completed in 2008, epitomizes this essential balance between security and design by providing an awe-inspiring entrance to the halls of government, enabling visitors to look up through six skylights for a unique view of the iconic Capitol Dome—all while adding new layers of security between visitors and the inner workings of the building. (Photo by MediaPunch Inc., Alamy Stock Photo)

Improving Accessibility and Security Through CPTED

If you look closely, you’ll start noticing it everywhere: the long, brightly-lit walkway with well-maintained vegetation along the sides, the line of stone benches running along the perimeter of a building in a popular tourist area, or the Instagram-worthy sculptures and architectural elements thoughtfully placed throughout an urban park.

These carefully constructed public spaces have components designed to delight and enhance the experience of the people who use them—but they also employ natural security techniques honed over decades to subtly create a safer space for all.

This approach, known as crime prevention through environmental design (CPTED), was first introduced in the 1970s and has steadily gained popularity since. Today, CPTED is a common component of physical security and architectural design—and for good reason. Urban areas are constantly evolving to support the influx of city dwellers; more than half of the world’s population lives in urban areas today, and that number is expected to increase, according to the United Nations. That growth, combined with the recent increase in soft target threats such as vehicle attacks and mass shootings, makes security in densely populated areas crucial.

However, the challenges faced by security practitioners to harden public spaces are numerous—the cost, the difficulty of retrofitting an existing area with new physical security components, and the implications that come with an increased visible security presence. This is where CPTED is especially useful, says Mark Schreiber, CPP, principal consultant of Safeguards Consulting, Inc., who is involved in ASIS standards development and multiple councils.

“CPTED is a whole other set of tools where we could apply security design to facilities but, instead of applying technology or a specific hardware, CPTED addresses overall facility design itself,” Schreiber says. “It’s important for security design aspects to be teaming up with other types of design—with landscape, civil, and structural engineering and physical security technology. We’re changing the physical environment that a human goes through and influencing the human’s behavior through those designs themselves, whether it’s outdoors or indoors, because that environment influences behavior naturally. People know when they feel safe, and a criminal knows where they’re more likely to get away with a crime because of the environment.”

While the basic principles of CPTED outlined in the 1970s remain the same today, they have become more nuanced—the approach is a careful balance of physical security, architecture, psychology, and perception. Successful implementation of CPTED components in public areas requires equal input between the landscape architects twho are designing a layout and the security principles needed to build a safe environment.

But for landscape architects, security is just one component of a larger plan. They also need to consider accessibility, aesthetics, municipal requirements, and resiliency—all of which need to be incorporated into one solution. While security and urban design often have differing—and, at times, clashing—approaches to how public spaces should be protected, the final result, when done well, is a seamless experience that leaves visitors feeling at ease.

“There are these fantastic themes of visitor use and experience, as well as public safety,” says Jill Cavanaugh, a partner at Beyer Blinder Belle Architects & Planners (BBB) in Washington, D.C.—a city full of national landmarks and tourist attractions.

“We always keep in the forefront of our mind that dichotomy and our obligation to ensure that when visitors leave these landmarks that they’re not taking away a sense of foreboding—you want them to feel safe and protected, but you don’t want to have that experience diminish their overall enjoyment of these landmarks,” says Cavanaugh.

Designing a Mall for the People

Cavanaugh and the architects at BBB have plenty of experience designing for some of the United States’ most stringent security requirements—following 9/11, they were tasked with increasing the safety of several national landmarks, including Smithsonian Institution museums, many of which line the National Mall in Washington, D.C.

“Because of the nature of the public spaces, monuments, and important buildings within the city, they all became vulnerable in so many ways, and there was a big need for them to be protected,” explains Hany Hassan, partner and director of BBB’s Washington, D.C., office. “We developed a comprehensive plan for the entire Mall with the intention to provide necessary security while being mindful of the quality, aesthetics, and historic nature of those buildings. We had to do it in a way that wouldn’t compromise the Mall’s symbolic nature of openness, freedom, and accessibility.”

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While security in the design was a top priority due to the buildings’ locations and symbolic importance, the architects had to keep other design aspects in mind.

“Our approach has to be dynamic enough to accommodate the things that oftentimes we can’t control,” Cavanaugh says. “The buildings in which we work are in dense urban areas, so we don’t have the luxury of a setback. How do you appropriately harden a building physically in a way that honors the aspects of the building that make it significant? We really maintain what makes the building special from a historic or aesthetic point of view, but [we] incorporate measures that are often invisible but do include the appropriate amount of structural resilience and electronic intrusion resistance.”

Scott Archer, a senior associate at BBB, tells Security Management that urban plans often incorporate a layered security approach, which is both more effective and less noticeable, ensuring that organizations are not relying on a single line of defense to stop all threats.

“The new visitor pavilion we designed for the Washington Monument isn’t designed to protect against a vehicle ramming, because that’s being protected against elsewhere,” says Archer. “This layered approach not only helps the user feel safe while still navigating those spaces with ease, but also allows the security apparatus to actually defend against things in a more discreet way. You can’t make it completely transparent in the way that it’s designed because you don’t want others to know what level of threat it’s designed to. It’s about the balance between allowing people to feel safe knowing that they’re protected without describing the level of protection.”

The results of BBB’s approach can be seen along the Mall today—but only to the careful observer. That marble ledge that’s the perfect place to sit while waiting in line to enter a museum also serves as a retaining wall and a barrier. The eye-catching sculpture that marks the entrance to the Smithsonian Institution’s National Museum of American History is reinforced to act as a bollard. A facility’s intricate wooden entryway may house a magnetometer. And there are many design components that meet strict federal security requirements and are almost impossible to detect—a slight slope of the sidewalk, unimposing vegetation, or a carefully placed trash can far from a building’s entrance.

“One of the best compliments we have received on this kind of work is that people didn’t even notice that there is perimeter security,” Hassan says. “When we do any of these projects, it’s not an exercise of flexing our muscles in designing an elaborate system—we want it to be nearly invisible.”

Internationally, though, the design approach might be less subtle. Cavanaugh, who leads many U.S. State Department projects overseas, explains that sometimes a facility’s security features should be showcased, not hidden.

“On these campuses, we always have perimeter security that looks like perimeter security, so that there’s a definite visual message to any visitor, whether friendly or unfriendly, that this is a protected U.S. military installation, even though it’s a diplomatic presence,” Cavanaugh says. “It’s important to emphasize security as a visual element but also have that diplomatic layer of encouraging visitors whose only interface with the United States might be through that post.”

A Team Approach

As CPTED best practices have become more widely understood throughout many industries, it is easier to work together to make design decisions among a multidisciplinary group, Schreiber notes.

“The great thing about CPTED is that it’s not a big lift—it’s relatively simple to implement because there’s not a lot of friction with the design process when you have trained professionals in the group,” Schreiber says. “Ultimately, it requires a team approach, proper education, and experience to implement CPTED. Common CPTED training programs educate a wide variety of people—security engineers and consultants, managers, architects, law enforcement professionals, and city planners. What it comes down to is that the principles are applicable to many different physical environments, including the built environment, and whoever is influencing that environment can use it in that case.”

Cavanaugh agrees, noting that the interactions between architects and security professionals often have a healthy tension to them that can result in innovative solutions that will satisfy everyone.

For example, Cavanaugh says: “If you have a challenge where you need a certain perimeter distance for a vehicle, there are many different ways you could work with the landscape to accomplish the same security objective. Those are some of the most fruitful dialogues because security professionals might perceive the solution to be a wall or fence, but there are other ways to address the issue and how to resolve it.”

Schreiber notes that ASIS is working with the International Organization for Standardization (ISO) to develop internationally agreed upon guidelines for CPTED best practices.

“We have made significant progress in making this standard into something that can be practically applied to any organization, including main CPTED principles and guidance that can be implemented,” Schreiber says.

Evolving with the Industry

Hassan says that the changes in physical security technology and the threats facilities face influence how the architects incorporate security into their designs. The evolution of x-ray and other screening technology, for example, allows architects to incorporate those security measures into the facility more seamlessly for clients seeking to create a more welcoming environment, he adds.

“The equipment is no longer as unsightly or intrusive, but more importantly we can now make the building more inviting when you enter, as opposed to being confronted with equipment when you step in the door,” Hassan says.

The constantly changing threat landscape is a challenge, especially when designing for a historic building that can’t be completely revamped to address new security concerns, he notes.

“What we hear from our clients is to design to the threat, but that’s always evolving,” Hassan says. “As much as we are trying to improve the systems and equipment we use, at the same time others trying to do harm are coming up with new ideas and ways to surpass that. It’s a constant challenge and competition between everybody to be able to protect ourselves from anyone trying to do any harm.”

This is where resiliency in a building’s design is especially important.

“When we’re designing places, whether it’s an urban landscape or a building, often these are giant monetary and time investments, so they usually aren’t temporary,” Archer explains. “Think about the longevity of an embassy overseas—that should ideally last for more than 100 years, but then the threat will be completely different. How we design in flexibility is really important, and we do that not just for security but for all types of issues within the building. We try to think about our master plans and our urban design as an exhibition of how this can come together in a way that makes sense for today and lays the landscape for how it might change over time without having to restart every 50 years.”

When it comes to resiliency, the architects take a holistic view about the mark they will make on structures that have existed for hundreds of years and, hopefully, will continue to serve the public for years to come.

“Solving security in design is one-dimensional, and when the threat changes it becomes antiquated,” Cavanaugh says. “If it’s solving more than one problem, though—if we’re layering in an infrastructure upgrade, bringing the building out of the flood plain by raising it 30 inches, and also accomplishing a vehicular barrier and incorporating accessibility—all of these things make design more resilient to both time and purpose. That’s where we find the most enjoyment: a multidimensional design that solves more than one problem in a way that’s sensible but also intuitive and will be more enduring in the way that people use it in the years to come.”

A Bird’s Eye View of Washington, D.C.

The Washington Monument—the striking obelisk-like structure perched on top of a hill overlooking the National Mall in Washington, D.C.—is one of the United States’ most distinct landmarks, but it was closed in 2016 for structural repairs and only reopened last month. The architects at Beyer Blinder Belle Architects and Planners (BBB) were tasked with building a new structure at the base of the monument to screen visitors before they ascend to the top of the tower.

The architects had a vision of an open, welcoming pavilion with glass walls and ceilings that would not hinder the 360-degree view from the monument. Melding this approach with the stringent security standards required for federal landmarks, though, made it one of the most challenging projects the firm has worked on, says Hany Hassan, partner and director of BBB’s Washington, D.C. office.

“We wanted to design the entrance in a way that reflects what the monument symbolizes, which is openness, freedom, and safety, and wanted people to be able to enter in a dignified way,” Hassan explains. “We went through a very arduous design process to develop multiple plans. In order to create that sense of dignity, we designed and developed a glass pavilion that is transparent, so you can actually see through it when you enter and look up towards the monument, so you’re never disconnected from that experience.”

BBB partner Jill Cavanaugh explains that the message the structure sends is intended to foster both accessibility and an understanding of the pavilion’s main purpose: security.

“The National Park Serv­ice wanted something that would convey that you are entering a screening facility, so in some ways it had to look purposeful while also incorporating discreet elements that the public doesn’t necessarily need to know,” Cavanaugh says. “Ultimately, we adopted a design that deliberately used glass so that it had a lighter touch that allowed people inside the security queue to look up and see the top of the monument.”

The architects ack­nowledged the challenges that came with designing a glass building to meet ballistic and blast requirements.

“We really put a lot of effort into the design to ensure that it was technically adequate, but we always go back to that visitor experience so we ensured that there’s daylight, there are views toward the Washington Monument and the monuments around you, while you’re up in that particular area waiting to get into the building,” Cavanaugh says.

Lilly Chapa is a freelance writer covering the security industry and a former Security Management associate editor.