Build your own Powered Air-Purifying Respirator

In response to the COVID-19 pandemic, Tetra Bio Distributed has developed a Powered Air-Purifying Respirator (Tetra PAPRa). Darryl Hwang, Ph.D., an Assistant Professor of Research at University of Southern California (USC) and a founder of Tetra Bio Distributed (TBD), initially started developing the Tetra PAPRa in 2020 as a follow up to the emergency 3D printed mask initiative in the early days of Personal Protective Equipment (PPE) shortages following the COVID pandemic. 

 

Galvanized by the COVID-19 pandemic, in the summer of 2020, Tetra Bio Distributed (TBD), a nonprofit organization dedicated to creating open-source solutions to cost-prohibitive medical technology, formed and began working towards effective and better fitting PPE. Some of the projects that TBD has created include: The Tetra Ventilator Splitter, which extends a single ventilator’s capacity to treat up to four patients, the Tetra Fitra – a fitment device, dramatically improving the fit of common flat fold N95 masks as well as the Tetra PAPRa – a powered air-purifying respirator.

 

In the earlier days of the pandemic, Daniel Stemen, manager of respiratory care for University of Southern California (USC), noted significant issues with N95 respirator masks in his field.  As the manager of respiratory care, Stemen was tasked with overseeing respiratory therapists treating COVID-19 patients, as well as testing the different pieces of Personal Protective Equipment (PPE) that his staff use to ensure that PPE are effective.

 

Stemen observed that a great many of the emergency use filtering face mask respirators (FFRs) the hospital had been given fit poorly. The lack of proper fit meant that his staff were at risk for COVID exposure, despite wearing PPE.

 

With the dilemma of ill-fitting PPE at hand, Stemen enlisted the aid of Tetra to design a fitment device that could go over a respirator. The result of this engineering effort was Fitra. This device was ultimately published in the Journal of Occupational and Environmental Medicine (https://pubmed.ncbi.nlm.nih.gov/33852548/), and it has been shown to improve the mask fit of flat fold N95 masks. The statistics gathered from Stemen’s study showed that community transmission among healthcare workers at USC was 0.27%, while other hospitals had community transmission rates of 5.5-7.7%, a dramatic decrease attributed largely to properly fitting PPE.

 

Despite the reduced risk of exposure and transmission amongst health-care workers, Dr. Hwang observed that after four hours or so of wearing properly fitting respirators, users began to develop headaches as they were re-breathing their exhaled carbon dioxide. Although property fitting respirators are much less likely to cause respiratory issues for those wearing them for shorter durations, the long hours and therefore longer exposure windows for health-care workers would mean a better solution was needed. With this in mind, Dr. Hwang created a working PAPRa in case of emergency need at hospitals.

 

At its core, the Tetra PAPRa utilizes a fairly straightforward idea of putting a fan behind a filter in an airtight box. The fan then pulls air through the filter and pushes that air through the hose. The hose in turn leads to a mask onto the wearer’s face. As the wearer breathes out, that air travels out through the filter in the front of the mask.

 

The first prototype device used a vacuum cleaner HEPA filter and a fan to pull air through to the wearer’s face, as well as a 12-volt power tool battery to provide power.  TBD is now working on the eighth iteration of that prototype device, with a goal to create a device that, when powered off, provides the same level of protection as a properly fit passive N95 and N99 respirator. And when powered on, provides enough airflow to the user to be comfortable to wear for hours at a time.

 

Despite Dr. Hwang’s initial goal being to create a working PAPRa in case of emergency need at hospitals, Tetra sees that the PAPRa has expanded its usefulness to a wider range of scenarios than just protecting health-care professionals. The organization has noted that the TETRA PAPRa can be a useful tool for immuno-compromised individuals, possibly allowing them to move more freely through society. It has also shown itself to be a useful breathing device for individuals who find they have to navigate fire seasons happening throughout various regions of the world and the associated smoke and air toxicity. 

 

As a nonprofit organization dedicated to creating open-source  medical technology, Tetra has made the STLs (stereolithography or Standard Tessellation Language) available for anyone to make the TETRA PAPRa if they want one. Those STLs can be found on their website under the heading, “Build a PAPRa”.

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Waste as a Resource: Charting the Journey of Plastic into Roads

Photo by Nareeta Martin on Unsplash

Plastic waste, omnipresent and seemingly immortal, pervades every corner of our planet. Once celebrated as the marvel of modern innovation, it now stands as a monument to our unchecked consumption. However, the tide is turning. From waste emerges an unexpected solution: using plastic waste in road construction.

The basic premise revolves around using plastic waste as a partial substitute for bitumen in roads. But how is this concept fairing on the ground? Let’s delve into five case studies from around the world:

India

Perhaps one of the earliest adopters of this method, India has paved thousands of kilometers of roads using plastic waste. The southern city of Chennai has been at the forefront. Their approach involves shredding the plastic to a specific size before mixing it with bitumen.

Learnings: The roads demonstrate increased resilience, especially during the monsoons. However, the importance of maintaining a consistent plastic size was a significant lesson, ensuring even distribution and longevity.

The Netherlands

This European nation took a modular approach. They introduced plastic road surfaces as pre-fabricated blocks, making installation and maintenance more manageable.

Learnings: The modular nature allows for quicker repair and replacement. Moreover, these blocks, when worn out, can be recycled, further pushing the sustainability envelope.

South Africa

Here, the approach was more community-centric. By involving local communities in plastic collection, not only were roads built, but jobs were also created.

Learnings: Beyond just infrastructure development, the project showcased how environmental solutions could have socio-economic benefits. The community ownership also ensured consistent plastic waste supply and road maintenance.

Australia

Down under, they embarked on a pilot project in Melbourne by using a mix of recycled plastics equivalent to plastics from over 3 million plastic bags, along with glass and toners from used print cartridges.

Learnings: The diversity in the type of plastics used provided a more comprehensive blueprint for cities worldwide. It emphasized the need for rigorous testing to determine the right mix and highlighted the potential to incorporate other recyclable materials.

United Kingdom

The UK’s approach was heavily research-driven. They launched trials in Cumbria to understand the long-term effects of plastic roads.

Learnings: The UK’s focus on research underscored the importance of longitudinal studies. While immediate benefits are evident, understanding the environmental and structural impact over years or decades is crucial for widespread adoption.

While these successes chart a hopeful course, the journey of integrating plastic waste into roads is not without its challenges:

  • Type of Plastic: Not all plastics are suited for road construction. This necessitates thorough segregation and compatibility checks.
  • Environmental Impact: There’s a risk of microplastics being released into the environment as roads wear down.
  • Health Concerns: Toxic fumes released during the melting process could pose health risks to workers and nearby communities.
  • Durability and Performance: The long-term performance of plastic roads in different conditions remains a topic of study.
  • Recycling Limitations: Some plastics lose their structural integrity after being recycled multiple times, impacting road longevity.
  • End-of-Life Management: The disposal of worn-out plastic roads without causing environmental harm is an unresolved challenge.
  • Economic Viability: Balancing the costs of treating and integrating plastic can be a hurdle.
  • Public Perception and Acceptance: Garnering public support and addressing concerns are essential for this initiative’s success.
  • Regulatory and Standards Development: The absence of standardized guidelines can complicate the construction process.
  • Supply Chain Challenges: Ensuring a consistent supply of suitable plastic waste, especially in less urbanized regions, can be challenging.

These examples, spread across different continents, highlight the adaptability and potential of integrating plastic waste into road construction. But it’s more than just a technical solution; it’s a paradigm shift. The message is clear: what we deem ‘waste’ today could be the ‘resource’ of tomorrow.

Each case study, with its unique approach and lessons, illustrates the significance of context. There’s no one-size-fits-all solution, but the underlying theme remains consistent — innovation, adaptability, and sustainability are key.

As we reflect on these global efforts, it becomes evident that the journey of plastic waste from being discarded to paving our roads is a testament to human ingenuity and resilience. Through these case studies, we discover myriad ways to reimagine waste, reshape infrastructure, and redefine the future. It’s a potent reminder that innovation emerges from challenges, and with commitment and vision, the path to change is always within reach.


Waste as a Resource: Charting the Journey of Plastic into Roads was originally published in Helpful Engineering on Medium, where people are continuing the conversation by highlighting and responding to this story.

Akon: An Odyssey of Light and Empowerment

Photo by Andreas Gücklhorn on Unsplash

Akon and Andy Rabens Pose For Photos with Entrepreneurs

In the sprawling expanses of Africa, as twilight descends, a new beacon of hope emerges. Not from global energy moguls or international benefactors, but from the pulsating world of music. At the helm? Akon. Once a maestro of chart-topping hits, he’s now orchestrating a different kind of rhythm: a rhythm of transformation.

Much of Africa’s tale has been shadowed by the absence of dependable electricity. Remote hamlets plunged into twilight, their only respite being the toxic fumes of kerosene lamps. But with Senegalese roots grounding him, Akon envisioned a brighter narrative.

Solar Embrace

Treading into the vast potential of the continent, Akon’s endeavor was nothing short of audacious. His ‘Akon Lighting Africa’ initiative, set in motion in 2014, sought to electrify remote corners across 25 nations. Aiming to impact a staggering 600 million lives, it was a symphony of ambition and altruism.

Central to this narrative was the sun. Africa, eternally kissed by sunlight, had its potent energy often overlooked. Akon and his team sought to capture this perennial force. Solar panels, once mere passive structures, were transformed into catalysts for change.

They bypassed the need for expansive infrastructures typically associated with traditional power. By decentralizing energy, Akon’s approach empowered communities at a granular level. Each village, each home, could become a fortress of self-reliance. This isn’t just electrification; it’s emancipation.

Empowering the Grassroots

A critical facet of Akon’s strategy was its deep-rooted commitment to nurturing local talent. This wasn’t a superficial transplantation of Western technology. Instead, a robust drive was undertaken to train local engineers and budding entrepreneurs.

By 2021, a formidable 5,000 individuals had been molded, ensuring that the projects didn’t just illuminate, but also invigorated. A local with the expertise to manage these solar setups ensured continuity. This wasn’t mere infrastructural deployment; it was the birth of an entirely new vocational realm. Here was a circular philosophy at play: knowledge and skills didn’t just arrive; they stayed, grew, and prospered.

A Financial Masterstroke

Financing such an ambitious venture was no small feat. Traditional models, often myopic in their vision, failed to grasp the intricacies of rural African electrification. But Akon and his team sketched a different blueprint.

With a deft mix of public and private alliances, they channeled investments from entities passionate about genuine societal impact. This wasn’t just about monetary gains; it was about dividends in human progress. The strategy cultivated sustainable growth without saddling nations with crushing debt.

In Akon’s journey, we glimpse more than just benevolence. It’s a masterclass in synergy, in uniting profit with purpose, leveraging sustainable avenues, and bestowing power upon local communities. It’s a circular dance of progress where every step forward is a leap for an entire community.

From the rhythm of his melodies, Akon once moved the world. Today, through the hum of countless electrified villages, he’s rewiring the continent’s future. One panel, one village, one heartbeat at a time.

The Lighthouse Effect and Africa’s Renaissance

Akon’s ambitious endeavor to illuminate the heart of Africa wasn’t just a testament to his commitment to his roots, but it became a beacon for many African celebrities and influencers who had made their name on international shores.

His journey began a ripple effect, sparking a reverse brain drain and an emergent African identity that champions global knowledge but with deeply rooted African solutions.

The Reverse Brain Drain

Historically, many of Africa’s best and brightest pursued opportunities abroad due to limited resources and infrastructural challenges at home. This led to a “brain drain,” where talent flocked to Western countries. However, Akon’s investment in Africa’s potential has ignited a trend that defies this narrative.

Returning Talent

Following Akon’s steps, several prominent personalities like Didier Drogba, the famed Ivorian footballer, established charitable foundations. Drogba’s foundation, in particular, has been involved in various health and education initiatives in Côte d’Ivoire. The success stories of these initiatives began attracting Africans abroad to consider returning home, leveraging their global experiences and network to make a difference.

Skills and Expertise

The returnees brought more than just capital. They brought with them skills, experiences, and insights from some of the world’s best institutions and companies. They began setting up enterprises, tech hubs, and initiatives in fields ranging from renewable energy to digital innovation and education.

Collaborative Initiatives

Akon’s venture prompted collaboration. Nigerian actress Genevieve Nnaji, for instance, used her platform to emphasize the importance of education and has actively participated in projects aimed at building schools in rural regions. Her collaboration with other returnees and foreign institutions is a testament to the synergies now taking root in Africa.

Crafting a New African Identity

Akon’s initiative has not only been about electrifying homes but also about reigniting pride in African identity.

Homegrown Solutions

This renewed identity champions the philosophy of “For Africa, By Africa.” Instead of wholly importing foreign solutions, there’s a significant emphasis on tailoring interventions to the unique challenges and strengths of African societies.

Cultural Renaissance

Alongside infrastructural developments, there’s been a palpable rejuvenation of African arts, music, literature, and cinema. Stars like Lupita Nyong’o and Chimamanda Ngozi Adichie are leveraging their global platforms to bring attention back to Africa, advocating for an appreciation of its rich traditions and potential.

Economic Paradigms

Africa is now being seen not just as a beneficiary of aid but as an equal partner in global economic dynamics. Akon’s foray into cryptocurrency with the launch of “Akoin” in Senegal is a prime example. This venture further emphasizes his vision of an economically self-reliant Africa, leveraging modern technological tools.

In essence, Akon’s electrification project has been much more than a philanthropic endeavor. It has lit the way for a generation of African influencers, beckoning them back to their roots, not out of obligation but opportunity.

With every village that lights up, it’s not just the darkness that’s kept at bay but also the shadows of outdated narratives. Akon and his league of influencers are championing a new story for Africa, one that blends its rich legacy with a luminous vision for the future.


Akon: An Odyssey of Light and Empowerment was originally published in Helpful Engineering on Medium, where people are continuing the conversation by highlighting and responding to this story.

Scaling the Skies: Navigating the Highs and Lows of Urban Vertical Farming

Photo by Nadine Primeau on Unsplash

In the heart of bustling cities with desert horizons, where skyscrapers cast long shadows and space is a premium, a new silhouette is emerging — vertical farms. These towering havens of greenery promise fresh produce even in the densest urban centers. Yet, with their rise come challenges: space constraints, soaring energy demands, hefty initial investments, and intricate upkeep. However, as innovators are proving, every problem has a solution. Let’s traverse the stacked aisles of urban vertical farming.

Tilling the Concrete Jungle

The dream is seductive: converting urban spaces into productivity hubs, reducing food miles, and offering city dwellers a literal taste of the farm. However, dreams often grapple with reality:

Space Constraints: While vertical farming minimizes horizontal space use, urban centers, especially in desert countries, offer limited space due to high property values.

Energy Appetite: Traditional farming thrives on sunlight. Vertical farms, however, often rely heavily on energy-intensive artificial lighting, especially in regions with prolonged hot and sun-scarce periods.

Capital Challenges: Setting up a vertical farm isn’t cheap. From specialized lighting to hydroponic systems, the initial costs can be daunting.

Maintenance Maze: These farms aren’t just about sowing and reaping; they’re complex systems requiring consistent monitoring and adjustments.

Innovating Upwards: Modular & Energy-Efficient Solutions

What if the challenges of space and energy could be turned into strengths?

Modular Systems: Think of them as Lego blocks for farmers. Customizable, expandable, and versatile, they can be fitted into various urban spaces, from rooftops to balconies to abandoned warehouses.

Tapping Renewable Energy: Solar panels or wind turbines can be integrated to harness natural energy. In sun-rich desert countries, this could counterbalance energy consumption.

Optimized Lighting: Advanced LED lights, tailored to emit specific wavelengths, can promote faster plant growth with less energy.

Smart Systems: Automated sensors and AI-driven analytics can reduce the need for constant human monitoring, optimizing conditions for plant growth while conserving resources.

Case Study: The Oasis Towers of Dubai

Dubai, with its sprawling skyscrapers and desert backdrop, epitomizes space and environmental challenges. Enter the Oasis Towers: a series of vertical farms powered entirely by solar panels, taking modularity to new heights. Designed as self-sufficient units, each module can be tailored to specific crops. The result? A 70% reduction in water usage and a significant drop in energy costs, producing yields comparable to larger traditional farms.

Cost-Effective and User-Friendly: Democratizing Vertical Farming

High-tech farming solutions can seem out of reach for small-scale urban farmers and community gardens. Yet, the future holds promise:

Shared Farming Spaces: Think co-working spaces, but for farmers. Shared facilities can spread out the costs, making the technology accessible to many.

Training and Support: Local governments and NGOs can offer training sessions, ensuring farmers reap the most from these systems.

Local Manufacturing: Producing components locally, especially in warm or desert countries, can reduce costs.

Simplified Systems for Community Gardens: Stripping down advanced systems to their essentials can provide community gardens with affordable vertical farming solutions.

Case Study: Lima’s Urban Green Revolution

Lima, with its warm climate, has seen community gardens sprout throughout the city. Faced with space constraints, locals innovated with cost-effective vertical solutions. Using locally sourced materials, combined with basic hydroponic systems and shared LED setups, yields have flourished. These community-driven initiatives not only feed neighbourhoods but also foster community ties and engagement.

Conclusion

Vertical farming, with its verdant towers and digital dashboards, offers more than just fresh produce; it paints a vision of a sustainable, resilient urban future. Warm and desert countries, often at the frontlines of climate change, stand to gain immensely from this agricultural renaissance.

Yet, the transition demands more than just technology; it requires a blend of innovation, community engagement, and a dash of audacity. As city skylines evolve, integrating green into the gray, vertical farming stands not as a mere trend but as a testament to human ingenuity in the face of challenges. From Lima’s community gardens to Dubai’s Oasis Towers, the future of farming is not just on the horizon, but reaching for the skies.


Scaling the Skies: Navigating the Highs and Lows of Urban Vertical Farming was originally published in Helpful Engineering on Medium, where people are continuing the conversation by highlighting and responding to this story.