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Blue Rescue: Using Discarded Masks to Inform Public Space Design

Discarded masks have become common street trash around the world. So many untreated, contaminated masks pose a risk for public health and the environment. Can designers help solve this new pollution crisis?

By observing patterns of mask litter and proposing design solutions, Sasaki urban designer Tianjiao Zhang, LEED AP ND, PLA and landscape architect Lanmuzhi Yang, ASLA, PLA, LEED AP ND hope to inspire designers to take action. Read on to learn more about their research.

Discarded masks and other protective equipment have become a common new street trash around the world. If you pay attention to the ground, you will likely find masks on sidewalks, in parks, near bus stations, and in parking lots. According to a report of OceanAsia, “The Impact of COVID-19 on Marine Plastic Pollution,” about 1.5 billion face masks likely polluted our oceans in 2020—if these masks were connected end-to-end, the total length of them would circle the earth 75 times.1 These masks pollute marine environments, harm marine life, and eventually cascade up the food chain to us, according to Laurent Seuront, CNRS.2

Research has pointed out that Coronavirus trash has caused a shift in the composition of the litter stream. The good news is that people have already started exploring innovative ways to address the problem of waste. A company called Plaxil in France announced they can recycle the masks and turn them to new plastic products such as face shields and containers;3 and research from the University of Petroleum and Energy Studies in Dehradun, India, has suggested that PPE litter could potentially be used as fossil fuel (although it is still a matter of debate since the emission of the plastic is toxic).4 Regardless of what we can do in the last step of waste management, the consensus is that it is urgent to have an efficient way to collect the PPE litter in the public space first.

How can we collect discarded masks in public space?

Answering this question is not as easy as you might think. The distribution of discarded masks is like a map of human activities. The concentrated areas of those masks vary in different urban spaces but are well aligned with people’s new lifestyle and travel patterns, which are shaped by the pandemic. Therefore, we ask ourselves, can we get a sense of the changes in the social life of urban spaces through observations of discarded masks? Can we develop strategies and guidelines that adapt to these changes to improve our urban spaces?

With that question in mind, we documented discarded masks found on walks throughout 2021 and 2022. We mainly focused on Boston, but also documented trips to Atlanta, New York, Denver, Oklahoma City, and Durham. After observing hundreds of miles of ground, we found over 200 discarded masks, and observed three types of spaces that have the most masks: streets, parks and recreational spaces, and parking spaces. Below are some examples of our observations and improvement suggestions.

Major mixed-use urban streets

These streets are characterized by shops, groceries, markets, and restaurants with outdoor dining areas. Diverse transportation methods are provided, including bus stops, subway stations, and bike lanes, which make the streets frequently used by the public. Receptacles can be found in nearly every intersection.


  1. Discarded masks are usually found in the areas around receptacles because masks are light and can be blown away while being discarded. We speculate that people are not comfortable using the traditional receptacles with handles during pandemic.
  2. The entrance / exit of shops and markets, where discarded masks were often found with gloves and wipes, is another hot spot. The switching moment in front of those indoor attractions slows down the pedestrians and creates congestion, which is challenging for most of the current sidewalks to accommodate.
  3. Outdoor dining areas have become more popular during good weather. However we have all experienced the inconvenience of finding a proper place for our masks after taking them off. Sometimes they are placed on the table or chairs, but they can be easily blown away.
  4. Discarded masks also accumulate in the areas around transit stops and rental bike stations, where people are taking off and putting on masks frequently. Existing receptacles are not close enough to such areas.

Potential Improvements:

  1. Effective receptacles that are easy to open, with dedicated discarded trash cans for masks as medical waste. Strategically place those receptacles closer to transit stops and building entrances.
  2. Wider sidewalks especially in front of major anchors/attractions to provide more comfortable space for people to take on and off masks.
  3. Devices where people can place their masks temporarily. They can be integrated as part of the fence, table, or chairs for outdoor dining areas, bike racks, and so forth.
  4. Signage, including icons on receptacles and bus stop posters, will be helpful to raise awareness and guide the mask collection.

Recreational Parks

The parks we observed vary from small pocket open spaces to big city parks, including urban plazas, linear parks, and waterfront open spaces. With looser mask requirements and popularity of vaccines, even though there are less people wearing masks, it is still easy to find discarded masks where there are recreational and gathering opportunities.


  1. Discarded masks were found around fields, running tracks, and other recreational spaces. We observed that people feel uncomfortable wearing masks for a long time during and after intense activities and fail to properly discard the masks.
  2. Masks can be found near seating areas along paths, on pedestrian bridges, in gardens, and other spaces. People tend to take off masks while sitting and having conversations.
  3. Places that have a higher volume of people, such as promenades, water fountain areas, playgrounds, dog parks, event lawns, and picnic zones have a higher chance of having discarded masks. Large numbers of discarded masks are associated with times of high activity during the day.
  4. Masks were also trapped in low, lush planted areas in parks and along waterfronts after being blown by the wind. Although few people visit the waterfront in winter, there were still many discarded masks found. They were likely blown away from other places and stayed there for a long time due to lack of in-time clean-up.

Potential Improvements:

  1. Along recreational trails and multi-use paths, provide an approachable mask collection method to ensure the masks can be quickly thrown into the container. The signage of the mask collection should be easily recognizable from a distance.
  2. For daytime activities, make sure to provide mask collection containers or receptacles closer to where people stay and along popular paths. For example, around sports fields and other recreational spaces, provide mask collection containers near the auditorium and paths to the parking lot.
  3. For night time activities, it is important to have a strategic lighting method to highlight the mask collecting areas, and locate those near spaces where traffic slows down, such as stairs or near park structures.
  4. Engage friends of the parks or other park NGOs to provide signage and flyers to the regular park users. Provide regular training opportunities for maintenance staff to appropriately clean-up the masks after big events.
  5. Set up a reporting platform (online or through an app/messages) to allow professional workers to collect discarded masks in time.

Parking Areas

Parking areas, including street parking and surface parking for restaurants, parks, shopping malls, markets, public transit stations, and campuses, are important transitional spaces that are easily ignored in open space studies. However, more than 30% of masks in our observation were found in parking areas. Street parking and surface parking show different characteristics when masks are taken off.


  1. We found discarded masks concentrated around street parking and on adjacent sidewalks. During winter time in Boston, they were buried by snow for several days. Even without snow, street cleaning happens once a week in these parking areas. This leaves enough time for pollution caused by discarded masks to spread with the melting snow.
  2. In surface parking, we found masks under vehicles, along the roads, near the sidewalks, and even in the nearby landscape. If there are fences or shrubs around the surface parking, masks easily accumulate there. Due to the flatness of the surface parking, the masks fly around and become hard to track.
  3. The accumulation time of masks in the parking lots is highly associated with the programs nearby. More masks tend to accumulate on weekends rather than on weekdays in commercial areas, but there’s no obvious difference near transit stations and campuses.

Potential Improvements:

  1. In parking lots and by metered street parking, integrating the mask collection box in a creative way would encourage people to throw masks away properly.
  2. In parking lots for a shopping center, it is important to encourage the store owners to provide a mask collection method. At markets, integrating the mask collection box with the carts could be helpful.
  3. Integrate flexible mask-collection methods with the fixed cleaning schedule. As mentioned in the previous section, utilize a reporting system via an app or texting so patrons can notify staff of mask collection needs.

Blue Rescue: Every Step Counts

Through our observations, we found that most discarded masks stay where people stop. They also travel with the wind, getting trapped in unreachable areas like forests and bodies of water where it is hard to collect them. When masks remain in the environment, they release microfibers5 and may increase the spread of infectious disease. Therefore, we want to encourage proper mask disposal in the public realm through design interventions, to reduce the environmental risk and protect ourselves.

With the popularity of vaccines and the control of the pandemic, Covid-19 will eventually fade away. Masks, however, are here to stay. As we begin to accept masks as a norm, we also accept the waste that comes with them.6 We know masks will remain in our life and stay in our environment for decades, and it’s not too late to take action against the pollution they cause. Even small interventions on the street can be impactful to our planet.

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