COVID-19 Implications of the Physical Interaction of Artificial Fog on Respiratory Aerosols

Written by Matthew Loss, Mark Katchen, Ilan Arvelo, Phil Arnold, Mona Shum

This content originally appeared on Medwin Publishers.  Access it here.

Positioning For Growth In The Healthy Buildings Technology Market

Report by Verdantix | June 2021
Excerpts provided by SafeTraces

SafeTraces is excited to have been included in a recent report by Verdantix, an independent market research leader, which highlights how Healthy Buildings have emerged as a major trend in the Smart Buildings market.

According to Verdanitx: “Since the COVID-19 pandemic, interest in healthy buildings has increased dramatically amongst employers and building technology providers, and as a result, is emerging as a major trend in the smart buildings market. This report examines the existing and emerging drivers that are propelling the trend for healthy buildings today, provides an overview of the technology landscape, offers vendors advice about capitalizing on this trend, and predicts the future direction. Smart building technology vendors should use this report to inform their healthy buildings product development and go-to-market strategies.”

Verdantix includes that:

“Even before the pandemic, there was growing evidence highlighting the business benefits of healthier buildings. For example, research conducted at the Harvard T.H. Chan School of Public Health found that doubling the standard specified indoor ventilation rate of 20 cubic feet per minute per person increased employee cognitive function, equivalent to a salary increase of $6,500 per employee per year. Healthy buildings also have the potential to add value for asset owners. A 2020 Massachusetts Institute of Technology (MIT) study found that in the US, healthy buildings achieve a rental premium of between 4.4% and 7.7% more per square foot than similar nearby non-certified and non-registered properties.”

“Real estate and human resources (HR) executives are starting to deploy indoor environmental sensors to gauge the effectiveness of new ventilation strategies and give employees peace of mind about the health of their workplaces. Firms are primarily looking to monitor IAQ, but other metrics, such as lighting, noise and temperature, are also important, to ensure occupant comfort. In our 2020 global survey, we found that 59% of real estate executives are already planning new investment in air quality sensors and analytics, to gain visibility on air quality[…] SafeTraces and UL offer services for verifying IAQ and the performance of HVAC systems.”


Verdantix subscribers can access the full report here.


SafeTraces delivers veriDART™, the market-leading solution for verifying safe indoor airflow. If you have any questions about how veriDART verifies engineering controls and HVAC performance for airborne pathogens to keep people safe in any indoor environment, reach out to us today.

Ventilation in Residential Care Environments

Project led by Dr. Kevin Grosskopf of the University of Nebraska–Lincoln with contributions from Roger Lautz, P.E. of Affiliated Engineers Incorporated, Phil Arnold of SafeTraces, Dr. Ehsan Mousavi-Rizi of Clemson University, and Dr. Josephine Lau of the University of Nebraska–Lincoln. 

This content originally appeared on Access it here.

Workplace Safety: Best Practice, Compliance, and Trust in the New Normal

How can employers reopen safely amidst increasing OSHA regulation and employee mistrust in workplace safety? Emerging technology can help.

Written by Erik Malmstrom | April 01, 2021

Amidst renewed urgency for reopening, employers confront two major issues – the proverbial regulatory hammer dropping and an alarming crisis of confidence in workplace safety. Emerging safety technologies can provide a major boost on both fronts.

First, President Biden has signaled a more robust approach to OSHA regulation and enforcement than his predecessor. Forthcoming Emergency Temporary Standards (ETS) regulations for employers, directed by an executive order issued on the first day of the Biden presidency, will be accompanied by a recently announced National Emphasis Program (NEP) for COVID-19 enforcement actions in higher hazard industries and an updated Enforcement Response Plan (ERP) to “prioritize COVID-19-related inspections involving deaths or multiple hospitalizations due to occupational exposures.”[1]

Second, a widely cited poll of 3,400 respondents across seven countries conducted by Edelman in late 2020 yielded striking results. Only half of employees believed that office spaces are safe. Employees placed the least amount of confidence in CEOs and senior managers to lead on return to work (14%). Most respondents received the majority of their virus-related information from mainstream and social media, but questioned its fundamental credibility.[2]

As employers prepare for return to work in a pandemic and post-pandemic world, how should they navigate this complex regulatory environment and overcome the trust deficit from employees? At risk of sounding overly simplistic, the answer is clear: they need to create a safe workplace based on best practice and regulation, and they need to communicate to employees with consistent, high quality, and reliable information.

How do we create a safe workplace? For an airborne pathogen like SARS-CoV-2, best practice and regulation have increasingly emphasized the critical importance of ventilation, filtration, and engineering controls to mitigate airborne exposure risk. The American Industrial Hygiene Association’s (AIHA) states, “Engineering controls that can keep infectious aerosols at very low levels indoors offer the greatest promise to protect non-healthcare workers and other vulnerable populations as we reopen our businesses and workplaces.”[3]

AIHA recommends “effective, simple-to-use, and inexpensive” tools to assess pathogenic exposure risk and verify efficacy of engineering controls in real world environments.[4] However, the reality is that existing tools fail to meet these three criteria, including applied tools like tracer gases, anemometers, and balometers for ventilation and particle challenge methods for filters, as well as theoretical tools like computational fluid dynamic modeling and volumetric airflow calculations.

From an efficacy standpoint, existing tools have two major drawbacks: (1) they are not aerosol-based and therefore are limited in their ability to verify ventilation and filtration efficacy for an aerosol contaminant like SARS-CoV-2; and (2) none provides a combined assessment of ventilation and filtration efficacy in one test, requiring triangulation between multiple methods to verify engineering controls holistically. Beyond efficacy, most existing tools are also overly complicated and costly, ultimately deterring regular effective verification.

As management guru Peter Drucker famously once said, “if you can’t measure it, you can’t improve it.” Fundamentally, toolbox limitations compromise our ability to accurately and regularly measure exposure risk and manage prevention and communication efforts, directly undermining workplace safety, regulatory compliance and employee confidence. Assessments often fail to produce high quality defensible data and thus create liability for employers. Moreover, employers’ limited ability to communicate data clearly, compellingly, and consistently perpetuates employee mistrust in workplace safety.

While the pandemic has exposed critical toolbox limitations, it has also spurred groundbreaking innovations that have pushed us closer to effective, simple to use, and inexpensive solutions that enhance workplace safety, regulatory compliance, and employee trust. As one example, our company SafeTraces has developed the first commercially available aerosol-based diagnostic solution for verifying ventilation and filtration efficacy in real world environments.

Developed with support from the National Institutes of Health and technical experts at leading research universities like Stanford and MIT, the veriDARTTM solution by SafeTraces leverages patented DNA-tagged tracer particles that safely mimic aerosol mobility and exposure in order to identify high-risk infection hotspots and transmission routes, regularly assess HVAC system performance at an affordable price point and ease of use, and inform remediations with a rigorous science-based, data-driven methodology.

SafeTraces has supported a diverse set of corporate, commercial real estate, and government clients, who have integrated veriDART into critical health, safety, and financial decision-making processes and ongoing environmental health and safety programs. Clients use veriDART to address two universal questions: (1) is air and airflow safe? (2) how and where should I target infection control planning and spending to enhance safety?

Practically, veriDART provides a baseline risk assessment for pathogenic exposure in real world spaces with the ability to regularly verify the same locations. It analyzes relative exposure risk reduction provided by increasing ventilation rates, upgrading MERV-level filters, employing standalone HEPA units, running fans, installing physical barriers, etc. Moreover, our data is independent, scientific, empirical, provided in heatmaps and other visual formats valuable for internal decision-making, regulatory compliance, and crisis communication to employees.

In conclusion, the rapidly evolving regulatory environment and pervasive employee trust deficit in workplace safety means that the cost of inaction for employers is high. Emerging OSHA regulation and enforcement compels employers to act immediately in order to become compliant, avoid citations and penalties, and limit legal liability with defensible data. Meanwhile, employers need to be proactive in enhancing workplace safety and communicating their efforts consistently with high quality, reliable data to employees like never before. Emerging technologies like veriDART are powerful solutions to these important ends.  

This article originally appeared on EHS Today. Read it here.



Emerging Technology for Verifying Engineering Controls

Groundbreaking aerosol-based solutions for verifying ventilation and filtration efficacy have emerged during the COVID-19 pandemic

Written by Erik Malmstrom | March 30, 2021

How do health facilities professionals verify that indoor air and airflow are safe? Facing a once-in-a-century airborne pathogen like SARS-CoV-2, the answer to this fundamental question has never been more important. They sometimes don’t know the answer because they cannot accurately quantify exposure risk and verify engineering controls in real world spaces. However, emerging technology is rapidly addressing this gap.

Three critical facts

Scientific, medical and public health experts have arrived at consensus on three critical facts over the course of the COVID-19 pandemic:

  • SARS-CoV-2 is transmitted via airborne droplets and aerosols — a fact not universally acknowledged in the early stages of the pandemic.
  • People in indoor environments are exposed to significantly greater infection risk than in outdoor environments, with enclosed areas, prolonged exposure and poor ventilation representing high-risk factors.
  • Engineering controls are critical to mitigating exposure risk, particularly ventilation and filtration.

Health care facility design prioritizes infection control and prevention via enhanced ventilation capabilities, HEPA filtration and negative pressure control. Nevertheless, the pandemic has placed unprecedented stress on these systems due to the high transmissibility of the virus and surges in infections overwhelming designated infection control areas and forcing non-designated areas to handle overflow.

Consequently, mechanical engineers face a complex challenge in verifying the efficacy of engineering controls in designated infection control areas, and responding to the need for rapid repurposing and/or retro-commissioning of areas not originally designed for infection control.

Traditionally, mechanical engineers employ a variety of applied and theoretical methods for verifying efficacy of engineering controls. For verifying ventilation efficacy, tracer-gas based methods using sulfur hexafluoride or carbon dioxide monitors, and direct measurement approaches using instruments, like thermal anemometers and balometers, are common practice.

For verifying filtration efficacy, particle-based methods like dispersed oil particulate for testing HEPA filter integrity and other mostly solid-matter challenge agents for sub-HEPA level filters are common practice. Frequently, non-applied methods augment applied methods like computational fluid dynamic modeling, volumetric airflow calculations and verification of product specifications for HVAC equipment.

In February 2021, the American Industrial Hygiene Association released the “Joint Consensus Statement on Addressing the Aerosol Transmission of SARS-CoV-2 and Recommendations for Preventing Occupational Exposures,” emphasizing the need for “(1) effective, (2) simple-to-use and (3) inexpensive ventilation assessment tools.” Implicit in this recommendation is that existing assessment tools fail to satisfy these three criteria.

From an efficacy standpoint, existing assessment tools have two major drawbacks: (1) They are not liquid aerosol-based and therefore not optimal for verifying ventilation and filtration efficacy for infectious aerosols like SARS-CoV-2, influenza and tuberculosis; and (2) none provide a combined assessment of ventilation and filtration efficacy within one test, requiring triangulation between multiple methods to verify engineering controls holistically.

Beyond efficacy, many practitioners do not consider existing solutions simple-to-use and/or inexpensive, resulting infrequent verification. Consequently, the baseline understanding of airflow, and ventilation and filtration efficacy in real world health care facilities is less robust than one would like. Moreover, the uniqueness of each facility, dynamic nature of airflow and infection risk within facilities, and natural wear and tear of mechanical and HVAC systems, underscores the importance of regular, ongoing verification that exceeds the capabilities of existing assessment tools.

Technical advances

However, the pandemic has spurred groundbreaking technological advances that have pushed us closer to effective, simple to use and inexpensive solutions that can be used routinely in real world spaces.

As one example, SafeTraces Inc., Pleasanton, Calif., has developed the first commercially available aerosol-based diagnostic solution for verifying ventilation and filtration efficacy for airborne pathogens. Developed with support from the National Institutes of Health and technical experts at leading research universities like Stanford and MIT, the veriDARTTM solution by SafeTraces leverages patented DNA-tagged tracer particles that safely mimic aerosol mobility and exposure to identify high-risk infection hotspots and transmission routes, regularly assesses HVAC system performance at an affordable price point and ease of use, and informs remediations with a rigorous science-based, data-driven methodology.

The veriDART™ by SafeTraces was used to iteratively verify negative pressure controls and airflow isolation between hot zone and safe area at a major superspreader site.

SafeTraces’ technology consists of two main components.

First, the particle technology enables the SafeTraces team to safely simulate the chemical composition, particle size distribution and detection method of virus-laden respiratory droplets and aerosols to verify ventilation and filtration efficacy in one test. DNA provides three significant advantages relative to existing methodologies: (1) DNA is highly sensitive to detection, meaning relatively small amounts of DNA can be used to test large areas at very precise levels; (2) unique DNA identifiers can be tagged to different tracer solutions, meaning multiple tracers can be released simultaneously simulating viral emissions at different points in a facility and each sample point can be tested against each unique tracer to develop a sophisticated assessment of aerosol mobility and exposure patterns; and (3) the DNA-tagged tracer solutions are completely safe, using food-grade, water-soluble materials that are FDA-Generally Recognized as Safe (FDA-GRAS), that are OSHA- and NIOSH-compliant, and that allow for occupants to be in the facility during testing.

Second, the data technology enables the SafeTraces team to precisely measure DNA signal strength, correlate test results to a relative exposure risk scale informed by infectious disease science and generate heatmaps and other visualizations to clearly communicate key findings and implications.

In recent months, SafeTraces has supported a diverse set of corporate, commercial real estate and government clients, that have integrated the veriDART solution into critical health, safety and financial decision-making processes and ongoing environmental health and safety programs.

Notably, SafeTraces has supported health care facilities in three main areas: (1) It verified the efficacy of engineering controls in designated infection control areas, verifying ventilation, filtration and negative pressure control performance against reference standards like American National Standards Institute/ASHRAE/American Society for Health Care Engineering’s Standard 170, Ventilation of Health Care Facilities; (2) it verified the efficacy of engineering controls in repurposed and/or retro-commissioned areas to improve building operation and maintenance procedures, often iteratively testing ventilation, filtration and negative pressure controls until a level of performance was achieved to ensure adequate infection control; and (3) it verified the efficacy of engineering controls in non-infection control areas, including high-risk areas like lobbies, waiting rooms and breakrooms.

Real-world examples illustrate the practical value of SafeTraces’ verification solution for infection control.

In late 2020, veriDART supported the retrofit of an existing long-term care facility resident wing into a temporary isolation unit, with modifications including increased ventilation rates, negative pressure controls, HEPA filtration and physical airflow barriers. The test results quantified the relative impact of varying ventilation rates, negative versus neutral airflow modes and other critical priorities, such as the “blast radius” of particle dispersion and particle detection levels in the HVAC system and filters to inform critical design decision-making.

In a separate engagement, SafeTraces supported a large prison during a major coronavirus outbreak that infected hundreds of inmates and staff. The crisis forced the prison’s leadership to evacuate the main prison complex and establish a large makeshift infection ward in a vacant warehouse on its premises. Prior to populating the ward, the prison’s leadership sought to verify airflow isolation and efficacy of negative pressure controls between the “hot zone” designated to house hundreds of infected inmates and the “safe area” designated for medical and administrative staff. The SafeTraces team worked with the prison’s facilities team to iteratively assess performance of negative pressure controls, with dramatic improvement between initial and final results and ultimately mitigating further viral spread (see graphic).

Quantifying risk

Emerging technologies are transforming the ability of health care facilities to quantify exposure risk and verify engineering controls for airborne pathogens with far-reaching consequences beyond the current pandemic. The benefits of these technologies-enabled solutions are enormous: enhancing patient and provider safety; regularly auditing HVAC system performance in ways never before possible; targeting remediation spending to its highest value opportunities; supporting compliance for rapidly evolving regulation; and eventually factoring into liability insurance and other mechanisms for evaluating and underwriting risk. It will be important for facilities engineers to be adaptive and consider how and where emerging technologies can best be integrated into their respective facilities for improved infection control and safety.

This article originally appeared on ASHE’s Health Facilities Management Magazine Online. Read it here.

veriDART™ by SafeTraces named in Verdantix 10 Exciting Indoor Air Quality Technologies To Watch in 2021

Written by SafeTraces | March 2021

SafeTraces  is proud to announce that our veriDART™ solution has been recognized as one of 10 exciting indoor air quality technologies to watch in 2021 by Verdantix, an independent market research leader.

According to Verdantix: “This report identifies 10 of the most innovative hardware and software technologies aimed at improving IAQ and HVAC operation. Corporate executives in facilities, EHS, human resources (HR) and real estate roles should use this report to understand the cutting-edge innovation occurring in the IAQ market and how these solutions can add value to their buildings.”

Verdantix highlights that:

“SafeTraces offers one-off and repeat validation services that provide insight into many of the operational functionalities of HVAC systems, such as filter performance, airflow patterns and fresh air ventilation rates.”

“Facilities managers with older HVAC systems and buildings should consider this solution to gauge viral transmission risk within their buildings and to identify methods to mitigate this risk.”


Verdantix subscribers can access the full report here.


SafeTraces is committed to ensuring the highest safety standards for the air we breathe, the food we eat, and the medication we take. If you have any questions about how  veriDART verifies real world HVAC system performance to mitigate exposure risk for airborne pathogens or are interested in purchasing the solution, reach out to us today.

Validation of the saniTracers® Sanitation Verification Method from Stainless Steel Environmental Surfaces

Written by Quin Chou, Nicole Herbold, and Lucia Cerrillo

This content originally appeared in the Journal of AOAC International.  Access it here.

Synthetic DNA Barcodes on Fruits and Vegetables Could Open the Door to Food and Agricultural Transparency

Featured in the Genetic Literacy Project

Written by Richard Owen | January 21, 2021

Few technologies can transform the relationship between growers and consumers like the promise of transparency. And with Covid, many of us demand even greater assurance that our food supply chain is as safe as possible. How are growers, distributors, processors, and grocery stores implementing transparency at each point in the supply chain?

I have been working in the agriculture industry for a long time. Over 30 years to be exact. But it wasn’t until I entered the highly-perishable fresh produce sector a decade ago that I gathered a true appreciation for how complicated – and how powerful – a transparent supply chain can be.

For many deep-rooted and emotional reasons, consumers have a close relationship with their fresh produce, scanning the produce aisle high and low for just the right piece of fruit to take home. And if at a farmer’s market, they’ll often quiz the farmer on how the product was grown, what crop protection products were used, and when was it picked. Arguably, the consumer’s relationship with fruits and vegetables is the most complicated one in the supermarket.

Those are the old days. Or at least that is the past, and singular, view of how consumers connect with the most perishable of products in their shopping cart.

The promise of technology and its impact on transparency will forever change the produce aisle, just like moving from 3G to 5G technology.


Different Views on Produce

When I speak to consumers about transparency, they reflect with varied responses. Some will say they want to get to know the specific grower that produced the beans or apples. What type of land was the crop raised on? What chemicals were sprayed, if any? What similar products can I purchase from that particular farmer?

When I speak with growers, transparency means building deeper loyalty with retailers and the consumers they serve (with hopes the loyalty is returned). But equally important, it’s a way to keep track of the product in case of food safety inquiries and also ensuring the quality of food arriving at its final destination — a nudge for growers to improve transparency.

A Push for Transparency: Savings & Security

Like with most technologies, there must be a benefit for increased transparency to become more ubiquitous. The most tangible benefit is financial, of course. That could come in the form of cost savings by eliminating a portion of the supply chain, or through increased margin at the checkout stand demanded by a premium label.

At the same time, it could also be an opportunity to protect market share. We’ve all seen the many recalls for romaine lettuce. We’re told of a few brands and bar codes to be aware of, but how do they know? The ability to trace-back a product to a particular warehouse or field is very important for a retailer and the consumer.

In the case of a food safety incident, quick trace-back can mean the difference between a small recall involving one or two growers, or a larger investigation that involves tens of millions of dollars of impacted product. And, if consumers fall ill from the incident, a bruised reputation for the retailer or brand, regardless of the outcome.


A Tool for Telling a Story

According to a 2020 study by the Food Marketing Institute (FMI) and Label Insight, shoppers have higher expectations for transparency when shopping online compared to in-store. Think back to the early days of COVID-19. According to FMI, online grocery purchases soared to 27% of all grocery spending for the March/April period of this year, compared to 14% in February.

This increase in online sales will undoubtedly drive consumers’ interest in a more transparent system. Why? In the store, you can look and feel the product you are about to purchase. Online, you need something more to tell the complete story of a product – how it was grown, when it was picked, size, and other quality attributes. That’s where transparency fills the gaps.

When you go to a grocery store, what do you want to know about your fruits and veggies? Why would you pick a particular brand of berries over another? Or what is it that you like about a particular store’s produce section? We often look for certain benefits when we purchase a product. It starts with the basics of getting a good product at a fair price. But beyond that, transparency helps the consumer make a purchase.

According to IRI Research, “consumers are more concerned than ever about where their food comes from. They are not only making their concerns widely known on social media; they are editing their shopping lists based on those concerns”. Not a surprise to see that the food transparency trend is growing, especially in the younger generations.


A Demand From Millennials

The effect of transparency on purchase decisions is even starker among the Millennial generation. According to a Snacking Trends Report, this demographic is increasingly making purchasing decisions based on “the tenets of self, society, and planet”, which feeds into sustainability.

Millennials have a real connection to the betterment of the planet, and brands need to be careful not to miss this. They must embrace the new level of transparency that Millennials have elevated. Just “talking the talk” will no longer cut it.

Farmers Demanding Price Visibility & Insights

Farmer acceptance of transparency technology is growing for multiple reasons. In the case of fresh produce, transparency allows the grower to look for efficiencies in the supply chain. Not only with their operation, but in the part of the chain above and below them.

Through an open purchasing platform, a grower may learn what the distributor pays the manufacturer for inputs, which puts them in a better negotiating position with the distributor, or even directly with the manufacturer.

Going the other direction in the supply chain, a grower may be able to directly access consumer insights on their products and brand. In the past, that information may have been maintained by retailers or distributors that, in turn, passed it along to the grower. The net result of this shift is quicker and better-informed decisions about what to grow.

And more importantly, they can look for particular attributes to provide the highest return from the marketplace. Similar to the consumer, it often comes down to economics: can I increase my revenue or lower my costs through the use of new technology that pulls up the shades somewhere else in the supply chain?


Promising Technologies in the Works

New technology has a way of telling the story of ‘what’s possible’. Here are two promising examples:

Founded in 2013, a Californian company called SafeTraces developed DNA “barcodes” that can be added to fruits and vegetables via a liquid spray or wax. What’s so special about that? The company takes a small piece of synthetic DNA from organisms not typically found in the produce section – like seaweed – which they mix with trace amounts of sugar and create a sprayable solution. According to the company, the spray is odorless, tasteless, and poses no food safety risk.

If a problem with the product arises, the DNA on the surface can be swabbed and identified within minutes. Placing the DNA barcode directly on fresh produce significantly reduces the potential for traceback information to be lost. Produce boxes, which traditionally carry the tracking information, are discarded long before anyone catches on to a problem.

In a different twist on innovative traceability technology, software company HarvestMark partnered with iFood Decision Sciences to create a solution that allows consumers to not only view each step along the supply chain, but to provide feedback and reward those brands they feel are doing the best job of transparency.

The product information is collected and shared with the consumer on an item-level basis. The consumer has instant feedback linked to the product’s age, origin, and location. This allows the grower to see how a specific product performs on the grocery store shelf and then make short and long-term production decisions.

In addition to the quality and analytical measurements provided to the grower, like temperature control, inventory monitoring, and supplier notifications, this traceability system also provides a mechanism for product recall in case there is a food safety incident.

The real power of the HarvestMark technology comes through the integration of both the consumer and analytical supply-chain feedback. A highly perishable raspberry variety, for example, might have great flavor and visual appeal according to consumer feedback. Through the analytics of the traceability software across the supply chain, the grower can maximize the shelf-life of the raspberries and reduce perishability at the store level. The result is increased income for both the grower and the retailer…and a happy customer who returns for repeat business.

The promise of this technology will be optimized even further using blockchain applications, which enables the industry to share data up and down the supply chain while maintaining the integrity of the data at each source.


The Bottom Line

A demand for transparency stems from both the consumer and the farmer in the hopes of ensuring affordability, safety, and sustainability. Implementing these advances will radically change supply chains in the years ahead. And although consumers may only notice slight differences in the produce section, we’ll reap its benefits by paying less for safer food that’s less likely to end up in the garbage.

Richard Owen has been a part of the Produce Marketing Association since 2009, when he joined as Director of Global Business Development and has served as Vice President of Global Membership and Engagement for the past three years. Find Richard on Twitter @richardo_pma

This content originally appeared on Dirt To Dinner and was also adapted for the Genetic Literacy Project.

Verifying Engineering Controls: The Critical Role of Emerging Technology

Featured in the AIHA Blog

Written by Erik Malmstrom, CEO of SafeTraces | December 22, 2020

A ceiling vent

2020 has been a wake-up call for the built environment. For years, indoor air quality has been a problem hidden in plain sight. Scientific research has detailed the scale and extent of this challenge, as well as the real human consequences evidenced in degraded cognitive function, illnesses, and absenteeism.

However, the current pandemic has elevated indoor air quality to an urgent matter of life and death. Infectious disease experts, including the CDC, have arrived at consensus regarding the significance of airborne and aerosol-based transmission of SARS-CoV-2. Moreover, viral infection has shown to be 18 times more likely indoors than outdoors, leading to a state of paralysis in much of the built environment.

The good news is that we know that air ventilation and filtration can make a major difference in mitigating airborne exposure risk indoors. According to the AIHA’s Guidance Document “Reducing the Risk of COVID-19 Using Engineering Controls” (PDF), “Engineering controls (including ventilation and filtration) that can keep infectious aerosols at very low levels indoors offer the greatest promise to protect non-healthcare workers and other vulnerable populations as we reopen our businesses and workplaces.”

The bad news is that the pandemic has exposed a critical gap in the toolbox of industrial hygienists and mechanical engineers—a science-based, data-driven diagnostic solution for verifying engineering controls in real-world indoor environments. Today, many rely on carbon dioxide monitors, computational fluid dynamic modeling, mathematical calculations, and even smoke and bubble testing, none of which accurately approximate the risk of infectious aerosols.

Our company offers the first diagnostic solution for verifying ventilation and filtration-focused engineering controls, specifically for infection control, through a novel methodology that safely mimics aerosol mobility and exposure levels with DNA-tagged tracer particles. During the pandemic, we have supported clients spanning commercial real estate, industrial plant operations, and public infrastructure, providing us the following key insights:

  • Assumptions vs. ground truth: Similar to traditional building commissioning studies, our test results invariably reveal important discrepancies between our client’s assumed understanding of airflow patterns, airborne exposure levels, and HVAC system performance in their facilities relative to our assessment findings. Frequently, we detect unanticipated airflow between building areas, mechanical faults in the HVAC system, among other surprising findings that would otherwise be unknown to the client and that increase occupational health and safety risk.
  • Multiplier effect of airborne interventions: Our test results indicate a valuable multiplier effect of ventilation and filtration, evidenced by lower detection levels of our tracer particles in both air and surface swab samples. In other words, effective ventilation and filtration not only can reduce airborne exposures by removing infectious aerosols in the air; it also can reduce fomite exposures by preventing infectious aerosols from depositing on surfaces and infecting building occupants.
  • Importance of in-room interventions: Our test results clearly and consistently indicate greater efficacy in reducing airborne exposures with in-room interventions like portable HEPA filters relative to HVAC system interventions like MERV-level upgrades. Our tracer particles often don’t make it to in-system filters, whereas portable HEPA filters remove our tracer particles closer to the point of risk where infected occupants are likely to infect others. Thus, several clients have reevaluated the soundness of proceeding with MERV-level upgrades when considering their occupational health and safety benefit relative to their financial cost.

In conclusion, it is paramount for all occupants and professionals to understand if the HVAC system and engineering controls are actually helping or not in preventing the spread of COVID-19. Emerging technologies have tremendous potential to provide a more accurate understanding of real-world occupational health and safety risk and mitigate this risk based on science and data.


– Erik Malmstrom

Erik Malmstrom is CEO of SafeTraces, a Bay Area technology company and provider of DNA-enabled diagnostic solutions for indoor air quality. Further information can be found at

This content originally appeared on the AIHA Blog. Read it here.