Our world plunged into a new set of uncomfortable norms in 2020. Mere months ago, life for much of the planet chugged along at its customary monotonous pace. Then, without forewarning, an insidious health threat thrust upon us.

COVID-19, colloquial for SARS-CoV-2, is a novel coronavirus that originated in China in late 2019. It quickly burned around the globe like a dry brush fire. Not since a hundred years ago has humanity confronted mask wearing and social distancing in efforts to prevent suffering on a pandemic scale.

A single COVID-19 viral particle is extremely small at 0.06 microns. This pure form of COVID-19 is not found outside a laboratory and would not survive even if it made its way into the environment. A single sneeze can eject 200 million COVID-19 particles into the airInstead, SARS-CoV-2, when expelled by infected human hosts, is encapsulated by mucus material.

Hosts shed airborne viral particles in two modalities: droplets and aerosols. Droplets are about 1 micron while aerosols approximate 0.5 microns. Millions of viral droplets and aerosols are sloughed-off by talking, laughing, coughing, sneezing, singing or simply by breathing. A single sneeze can eject 200 million COVID-19 particles into the air.

Portable air purifiers provide a potent tool in the fight to reduce the spread of COVID-19. The selection and deployment of an appropriate purifier are instrumental in lessening airborne viral droplets and aerosols. Advanced purification units can sterilize air as well as trap pathogens. This best-of-both-worlds approach to disease prevention is vitally important.

HEPA Filtration

An air purifier must have a medical-grade HEPA filter if the goal is trapping airborne pathogens. HEPA filters remove 99.97% of particles down to 0.3 microns in size. HEPA has different levels. The H-values of HEPA range from H10 through H14. Medical-grade HEPA is H13 or higher and provides filtration efficiencies of 99.95% of 0.1 micron-size particles per liter of air. As a result, medical-grade HEPA is highly effective in COVID-19 droplet and aerosol elimination.

Clear Air Delivery Rate

Clean Air Delivery Rate (CADR) is a critical metric of a purifier's ability to remove particles of a given size and is measured in Cubic Feet per Minute (CFM.) This drastically differs from a CFM metric alone. CFM as a standalone value demonstrates only the volume of air moved through a system without regard to particle removal. CADR is a compulsory and precise method of comparing air purifiers in a standardized manner. Choosing a purifier with the highest CADR is always preferable. Experts recommend devices with a CADR that moves the total air volume of a room through the purifier 5 to 6 times per hour.

Portable air purifiers provide a potent tool in the fight to reduce the spread of COVID-19

Ultraviolent Light

Ultraviolent Light (UV) is a powerful sterilization strategy. UV is used in medical settings worldwide for this purpose. While utilizing UV in a purifier is advantageous, selecting a device with UV in 254 nm wavelength is paramount. UV outside of this wavelength can excite oxygen into creating harmful ozone molecules consisting of 3 oxygen atoms. Cutting-edge air purifiers have 254 nm UV bulbs formulated with doped quartz. Such doping precludes secondary harmonic UV wavelengths from radiating from the bulb. UV is an invaluable element of air decontamination if ensured UV is 254 nm and doped bulbs are utilized.


Some air purifiers employ photocatalytic Titanium Dioxide (TiO2) membranes to complement their UV. The resulting photocatalysis dramatically enhances the sanitizing effects of UV. A TiO2 photocatalytic reaction under UV radiation provides additional disinfection pathways in addition to UV directly acting upon pathogens. Thus, both direct UV and photocatalysis provide exceedingly effective methods of microorganism degradation and destruction.

Other Technologies

Other technologies are found in purifiers, such as sophisticated filters to thwart VOC/TVOC compounds and negative ion generation. Negative ions have antibacterial properties, including marked reductions of acinetobacter transmission. Also, negative ions have the beneficial capacity to precipitate airborne PM1.0 and PM2.5 particulate matter, which are impurities that affects health.

Advanced purification units can sterilize air as well as trap pathogens

With the COVID-19 age upon us, portable air purifiers provide enormously powerful weapons in protecting the health of persons inside enclosed spaces. Air purification coupled with other air quality measures -- such as ensuring a suitable amount of outside air exchange, air agitation with fans and upgrading existing HVAC filters with MERV-13 -- present an effective and comprehensive approach to health and safety.

Share with LinkedIn Share with Twitter Share with Facebook Share with Facebook
Download PDF version Download PDF version

Author profile

R. William Pierce Senior Process Engineer, VironAire Inc.

R. William Pierce is currently a senior process engineer for VironAire, a medical equipment manufacturer based in Palm Springs, California. William has been instrumental in the development of several air monitoring and purification systems, including VironAire’s iNOX19 high-performance H13 HEPA filters. Previously, he consulted to the National Aeronautics and Space Administration in filtrate material sciences. He is a graduate of California State University at Chico.

In case you missed it

The Impact Of Millennials And Other HVAC Industry Trends
The Impact Of Millennials And Other HVAC Industry Trends

Millennials have been shaped by their experiences growing up with technology and by their heightened awareness of the environment. These facets of a consumer market dominated by millennials will guide the future of the HVAC market over the next several years. Each generation reshapes markets in their own image. In the case of millennials, trends and behaviors are influencing how companies design new solutions, including those in the world of HVAC. Sustainable solutions and personalized experiences Millennials place a premium on sustainable solutions that reduce their environmental impact Millennials place a premium on sustainable solutions that reduce their environmental impact. Millennials also want more personalized and convenient experiences, and they value enhanced customer service support. New systems designed with a personalized and ecological mindset are amplifying efficiency and convenience and giving unprecedented control to create a truly connected home for technophilic millennials. Future HVAC products to cater to millennials The challenges of catering to millennials is one of the trends LG Electronics has listed among those likely to impact the HVAC industry in the months and years ahead. The trends are directly guiding LG’s product mix, including WiFi-enabled indoor units and LG’s Smart ThinQ application, which put the ability to control a home’s comfort system at the consumer’s fingertips. Here are some other trends to watch, listed by LG Electronics, when looking ahead to 2021 and beyond: Greener solutions on the horizon: Beyond appealing to millennial sensitivities, green solutions have a long list of their own advantages. Industry providers are responding by creating more sustainable and efficient products to enable customers to reduce their carbon footprints. LG Inverter air conditioning systems are designed to minimize efficiency losses, provide sustainable energy savings and contribute to lower lifecycle costs. More efficiency and reduced costs: Geothermal heat pumps have quickly proven themselves to be an alternative energy source, offering both warming and cooling capabilities. They are a highly effective and renewable energy source that can transfer heat from the ground to cool and heat buildings. Minimizing greenhouse gas emissions: Connecting HVAC to the electrical grid highlights the importance of reducing greenhouse gas emissions. Air-to-water heat pumps and other solutions can generate cooling and heating from one unit, thus furthering the transition from natural gas, fuel oil or coal. Fulfilling the need for new employees: The next generation of HVAC engineers and technicians requires training programs. LG Air Conditioning Academies provide training and skills programs around the world to empower the new generation of HVAC professionals. The impact of COVID-19: The pandemic has created a need for greater safety precautions within the HVAC industry. Remote working trends and additional precautions will likely continue to impact the industry even post-pandemic. LG HVAC systems are evolving to better aid the road to recovery and to prepare for the new normal with optimal solutions for the ever-changing challenges.

Residential HVAC Continues to Show Business Strength Amid COVID-19
Residential HVAC Continues to Show Business Strength Amid COVID-19

The entire economy has been severely impacted by COVID-19, with small businesses being hit the worst. These businesses make up 47% of the private labor force and contribute 44% to GDP in the United States. Thankfully, not all small businesses are the same. Jobber’s Home Service Economic Report: Summer Edition analyzes the performance of the Home Service category throughout 2020, and shows a positive path towards recovery. It shows that the Contracting segment, which includes HVAC businesses, had its first full quarter of positive year-over-year growth since the start of the pandemic. As we look ahead to the future, it’s important to reflect on the past year and understand how residential HVAC, and the Home Service category as a whole, has fared through this pandemic and the economic turbulence that it has caused. Jobber’s report highlights some trends and key findings that can help guide companies through the end of the year and into 2021. The Residential HVAC Industry Falls within a Strong Home Service Category Wrapping up the third quarter, it’s clear that the Home Service category—including residential HVAC—continued to recover as the economy opened up and consumer demand rebounded. With the exception of Grocery Stores and General Merchandise Stores, Home Service was the most stable category through the peak of the pandemic. It also recovered very well through June and into Q3, showing 10% year-over-year growth in September, compared to other categories such as Clothing Stores and Restaurants, which registered declines of 12% and 14% respectively. New Work Scheduled Finds Pre-Pandemic Success New work being scheduled is an early inductor of the health of Home Service businesses, and a proxy for consumer demand. When the pandemic first hit, the Contracting segment, which consists of industries such as Construction, Plumbing, and HVAC, saw a sharp decline in new work scheduled in March and April. Residential HVAC continued to recover as the economy opened upAt its lowest point, Contracting saw new work decline by 23% year-over-year as states across the country began implementing stay-at-home directives and consumer spending tightened. This impacted revenues in April and May, where growth declined 15% year-over-year, roughly 25% below expectations. Despite this dip during the initial peak of the pandemic, new work scheduled for the Contracting segment started to show signs of recovery from May onwards, hitting a record high for the year in June with 15% growth year-over-year, and consistent positive growth since then. As a result, the third quarter revenues for this segment have also shown positive results. Although the growth was moderate earlier in the quarter, the Contracting segment finished strong with 12% year-over-year revenue growth in September, matching pre-pandemic levels. Employment Growth Sees Upward Trajectory In April, the U.S. unemployment rate shot up to a record high 14.7% largely due to COVID-19 layoffs, but improved to 10.2% in July as the economy began to reopen, and further to 7.9% by September. For Home Service specifically, the category began 2020 with positive employment growth in Q1 that outpaced the employment growth in Total Nonfarm. However, stay-at-home orders in April caused employment growth year-over-year in Home Service to drop drastically by 12.9%, although this was still a bit better than the 13.4% drop for Total Nonfarm employment. Since this drop, Home Service has seen rapid recovery, with September employment only showing a decline of 3.9% year-over-year while Total Nonfarm shows a decline of 6.4%. Digital Payments on the Rise Despite Historic Resistance The Contracting segment has historically been a bit slower to adopt digital payments as these businesses often have large invoice sizes, and don’t want to collect payment using methods that can deteriorate their margins. However, according to market reports, the adoption of digital payments has accelerated significantly due to the COVID-19 pandemic. The adoption of digital payments has accelerated significantly due to the COVID-19 pandemicSpecifically, the estimated percentage of transaction values done digitally in 2025 is now expected to be 67% rather than the previous estimate of 57%. In our data, we saw a significant increase from January to May, from 32% to 37%, in the share of payments being collected through digital methods, compared to other methods such as cash or check. While each business has its own unique dynamics related to e-payment usage, it will be interesting to monitor this trend heading into the new year, as social distancing continues, and more companies commit to improving their technology usage. Although there has been a positive economic turnaround for all categories towards the end of Q2 and through Q3, it’s difficult to predict where we are going with the recent rise in COVID-19 cases throughout the country. While consumer spending and employment have recovered from the massive declines they saw in early Q2, they seem to be stagnating a bit below their pre-COVID growth levels, suggesting that both consumers and businesses are remaining cautious. One thing is clear though, Home Service as a category is incredibly resilient as most businesses managed to survive through unprecedented economic hardship, while finding new and better ways to service their customers.

Could Thermic Heat-Generating Paint Play a Crucial Role in an HVAC System?
Could Thermic Heat-Generating Paint Play a Crucial Role in an HVAC System?

Is wall paint a feasible element in an HVAC system? That’s the supposition that underpins Thermic heat-generating paint, which is applied like conventional paint but then can heat up a room when it is connected to a safe level of 24 volts of electricity. The paint is a water-based, solvent-free and low-pollutant dispersion that provides a wafer-thin carbon specialty coating (about 0.4 mm), which can be connected to a low-current circuit to provide radiant heat. In effect, the product allows a house painter and/or an electrician to “install” a heating system. infrared heating panel “Thermic heat-generating paint can be processed particularly evenly and is so electrically conductive that a low voltage of 24 volts is sufficient to generate high outputs of up to 100 watts,” says Hans Schulte, Director of Thermic Coating Systems Ltd., based in Chester, United Kingdom. The low voltage is selected in accordance with the “toy safety directive,” so it is safe to touch. The coating can be applied to any wall, ceiling or floor and transform it, in effect, into an infrared heating panel, says the manufacturer. The company suggests the coating would be particularly useful for builders planning a low-energy house. One liter of Thermic Paint costs 149 Euros ($175). low energy requirement This requires technology that provides heat at short notice - at the time and place where it is needed" “In new buildings, the trend is toward intelligent heating solutions that flexibly cover the low energy requirement and adapt to the needs of the user,” says Schulte. “This requires technology that provides heat at short notice - at the time and place where it is needed." The responsiveness is an advantage when compared to heat pumps, which require a lead time of several hours to change the temperature in a room, says Schulte. The system is particularly useful for concrete surfaces, and normal walls made of brick or wood are sufficient. The combination of products also has an almost unlimited lifespan and does not require maintenance, says the manufacturer. The coating can be painted over with standard colors. Low energy use is another advantage, with Thermic Paint providing the highest infrared heat radiation at the lowest energy consumption, according to the company. wall coating system With an efficient layout and intelligent control, the wall coating system can save more than 50% of a required heat load. An area of one square meter can achieve a surface temperature of 118 degrees F, so a few such areas on walls or ceiling can provide a warm comfort level. In effect, 6 square meters of heating area would be needed to heat a 25 square meter (269 square foot) living room, according to Thermic Coating. The company’s website says they are amenable to “attractive opportunities for cooperation.” Transformers are used to supply electricity, transforming the mains voltage to the low operating voltage. Thermic Coatings sees use of large-sized infrared heaters on low temperature on walls and ceiling as the future. It is most efficient to locate the heat paint in the coldest parts of a room, says the company. The paint should cover an area as big as possible to ensure lowest energy consumption while still heating the room.