With a New, More Contagious Covid-19 Arriving, Let Moisture Be Another — and Invisible — Mask

40 min readJan 3, 2021

Overview

Managing humidity anywhere is an immediate, painless, and science-based solution to beating any killer virus and even bacteria and other microbes. Since Covid-19 is getting more effective at spreading itself, we have to become more cost-effective at protecting ourselves. Air moisture is essentially a cost-effective, invisible mask that one doesn’t need to wear, and that anyone can afford (after all, it’s just water), is quite easy to monitor (simply by looking for static electricity and water condensation after a few key steps), is quick to adjust in the air around us (via boiling water, or instead even using just cups of water and tissue paper), easy to implement (just an awareness campaign and, typically, a three-minute or less education effort), and offers us all better protection at school, work, home, and leisure. Most importantly, it could save 100,000 people or more this year in the U.S. alone, well over a million jobs, and many more beyond that while reducing debilitating long-terms health effects, personal financial suffering, and economic calamity. Given that viruses will keep mutating, and pandemics will consequently keep returning in the future, being ready to do these steps every year can be a crucial public safety checklist.

by Terry Rajasenan, 1/10/21 (original research distributed 3/24/20)

An “Invisible Mask Initiative” Can Save Many — Quickly

We are entering a crossroads moment for our battle against a raging pandemic, one that continues to set new records in terms of infections and deaths, both here in the U.S. and around the world. The good news is that a seemingly effective set of vaccines has been developed. The bad news, however, is two-fold:

Effectiveness may take time to reach everyone, and given how viruses evolve, may not last as long as we would hope
Effectiveness — as we have seen with other proven tools (e.g., testing, tracing, quarantines, masks, etc.) — may fail in execution, not the least of which is whether it is even adopted by enough people to stem the tide

Could a simple graphic describing an invisible mask initiative (IMI), based on managing protective air moisture levels anywhere, teach people how to quickly and cost-effectively save the lives of hundreds of thousands of people around the world, including over 100,000 in the U.S. and Canada this winter and beyond, and the livelihoods (read: jobs) of millions, this coming year? Our research findings [1] suggest that indeed this is the case. The reasons are simple:

A. It just requires an awareness campaign and easy education effort to succeed that even children can explain to multiple generations of their family, and can be applied in virtually any setting where people will be in an indoor environment for more than 15 minutes, like home, the workplace, classrooms, and even restaurants and theaters

B. It inexpensively requires just water, cups, tissue paper, and a glass of water or simply a nearby window

C. It can be effectively learned in just 1 minute (i.e., each of the 3 sections take 5 seconds to read, then can be repeated 4 times in that minute). It can also be texted to people’s phones, put on a website for browser access, or printed to put into wallets

Let us explain by revealing the IMI graphic first:

Though everyone should always wear a mask, even when indoors (if you are with people with whom you don’t normally reside), there is pandemic fatigue setting in around the world, and at perhaps the worst possible time. Why? Because it may be that with more contagious Covid variants, even one mask may not be enough. Recently, President-elect Biden has been seen donning 2 masks, the CDC has noted the importance of masks with at least 2 layers, and reduction of contamination risk is also enabled by having another mask serving as a protective cover. However, wearing two masks obviously will make it even harder to breathe comfortably than wearing one. And the greater protection may not be significant, especially relative to discomfort. [2]

In the rest of this article, we will walk through the research that led to the discovery, starting with some background. Ultimately, as a scientific research organization, our objective is to study whether there is a public health and economic benefit of the areas where the awareness campaign is implemented. We hope this public safety initiative will show reductions in infections, preventable deaths, job and business losses, etc., compared to prior periods for that area and also when contrasted to those areas where the awareness campaign has not been fully socialized.

The Original Crisis: Covid-19

Would anyone have imagined that, in the most wealthy and, by key measures, the most technologically advanced nation in the world, the current pandemic would be a “mass casualty event”, surpassing American fatalities in any single event of the last hundred years?

Actually, today — Jan. 10th, 2021 — the U.S. death toll has been 381,497 [3],which in the past 100 years is more than the combat deaths in many years of wars from World War 2, the Vietnam War, the Korean War, Afghanistan/Iraq Wars, as well as the 9/11 attack combined (i.e., a total of 381,376) [3] — and all in less than a year since the pandemic arrived in the U.S. on January 22nd of 2020 according to the CDC.

And imagine that, after such a year, the worst would be yet to come? But that is our current situation, according to health experts [4], who say the worst is indeed still to come, at least in terms of total infections, as it is expected that colder weather will lead to more people meeting people indoors where the transmission risk is higher.

As predicted, Covid-19 deaths reached a new records this past week as well [5], exceeding 4,000 deaths multiple times, and now some projections are suggesting 5,000 or even 6,000 deaths a day are in our future [6], which, with uncontrolled spread, would be likely.

The comparison to combat deaths is also apt, since essentially battlefield triage has begun — Los Angeles County ambulance crews were told this past week not to transport Covid-19 patients with little chance of survival to the hospitals [7], and triage officers are set to arrive at L.A. County hospitals [8]. The denial of care fear that emerged at the pandemic’s start is now here at a broad scale, given the record level of infections in the U.S. and around the world.

The New Crisis: Virus Mutations

However, we now also confront three new challenges that do not bode well for our trajectory:

Mutated variants of the virus with a higher level of contagiousness, with faster and wider spread, and higher than expected level of mutations [9]
Asymptomatic transmission is the majority (59%) of the virus’ spread, so it is not enough to have sick people stay home, nor will contact tracing and quarantining be effective — virtually any contact among groups of people could lead to contraction of Covid-19 [10]
A risk that vaccines will be less effective, as is currently feared with the South Africa Covid-19 variant [11], with less protection than initially hoped and more risk of infection and possible death

The third point above is because the South African variant’s mutation could change how the virus attacks and thus bypass the vaccine protection. It has 22 significant changes from previous strains of the coronavirus, and the United Kingdom strain has 17 mutations (both an unusually high number of mutations), and some of them are related to the spike proteins found on top of the virus, which is the target for antibodies generated by the vaccines [12]. The Pfizer-BioNTech vaccine protects against a key mutation found in fast-spreading virus variants, one study shows [13], but we are not yet sure about other vaccines, nor do we know if other mutations will occur that hurdle that defense.

The CDC now foresees spread in U.S. of this highly contagious coronavirus variant [14]. The new UK variant has now been found in Pa. and at least 6 other states [15]. Also, around a dozen cases are known in neighboring Canada [16].

The urgency is that, as some have termed, the mutated virus is a “ticking time bomb” [17], as they note these more transmissible variants (up to 70% more infectious) of COVID-19 are perhaps more catastrophic than the original virus. Given the current stage of the pandemic, it subjects us to a more contagious virus spreading with exponential growth, whereas the risk from increased severity would have increased only linearly (as it would impact only those infected).

In short, greater transmissibility infects a population in a much shorter time, before a vaccine rollout that gives herd immunity could save lives and, for many, the priority of livelihoods.

This is especially true when uncontrolled spread is already occurring throughout the United States, and when healthcare is already at the point of triage and denial of care in some areas of the nation. That inability to get healthcare will only grow larger without taking action immediately, given this threat of faster exponential growth. Here are two different views of that exponential growth in America during the beginning of the first Covid-19 virus outbreak versus other nations with the same virus [18]:

Now, we conceivably have a new outbreak. These graphs help compare us to others during the beginnings of an outbreak, such as we would see from a new strain of a virus, and the consequent scale and enormity of the problem we will likely see here in the U.S. again relative to other nations, due to specific factors where we lag (e.g., masks, social distancing, testing, and isolating/quarantining).

In addition, if holiday travel is any indicator, there may be a sense of complacency on the virus given the emergence of vaccine options. Young people seemed to be less vulnerable; now they are getting sick at a surprising rate. Lockdowns seemed to work in the spring, but now the virus is spreading in places such as London with very strict stay-at-home rules. The easier spread of these new viral variants are overwhelming the community and their locally available healthcare resources due to public fatigue, disregard for restrictions, congregating and travel during the holidays that throws caution to the wind, and delays in rolling out the vaccine. The daily national death toll this week exceeded 4,000 people, or one death every 22 seconds [19].

This jump in infections will not only increase the risk of death, long-term debility, or pre-existing conditions, but also increase the human suffering from economic pain and social isolation.

Why Vaccines Alone Are Not the Panacea

The current Covid-19 virus strain we’ve been battling will likely last longer than we had hoped, if the current trends of vaccine production and distribution hold [20], leading to a significant human toll until as late as 2022.

In response, President-elect Joe Biden has now promised to rush out the reserve of second dose vaccines to reach more people faster with the first dose, which does make sense if those doses are replenished in time [21],

Yet, huge challenges remain. How effective are vaccines quickly, such as with one dose of the Pfizer-BioNTech? Studies show it is over 70%, then 95% effective after a second dose that requires three weeks before administering [22]. The problems with this sort of option as a “rapid response” are:

There are still simply not enough vaccines for everyone any time soon. And using just one dose may provide significant immunity, but it is not known how long protection lasts [23]
Even if there were enough doses, it is a major logistics issue to put needle-to-arm, as we are finding out. It will take well past this winter to protect everyone — and that is for the people willing to accept it, especially given anti-vax disinformation
We do not know if (or more likely when) a new vaccine-resistant mutation of Covid-19 will occur, or at least a new pandemic-level virus will come again where we will not have the head start — believe it or not — that we had for this virus [24]
A 70% effectiveness rate still means around 1 in 3 who get the vaccine still will contract Covid-19, and the vaccine is not 100% effective (i.e., at 95%, still a risk that 1 in 20 people won’t see protection even after 2 doses). However, there’s more — there may be a risk if people don’t get a second dose of the same vaccine as the first (i.e., if get Pfizer vaccine the first time, get Pfizer the second time also), or it doesn’t happen in time, as the second dose of the Pfizer vaccine is typically given after three weeks and the Moderna after four weeks. After a week or two, one has some level of immunity, but could certainly get Covid-19 if exposed to the coronavirus [25]. To be safe it takes 3 weeks after the 2nd dose — so 6 weeks in all, then perhaps more if there was a mismatch or an unsafe delay, or even poor quality control of the batch production, distribution, or storage
Perhaps most alarmingly, the vaccine has not yet been shown to reduce transmission of the virus. It is not known if people vaccinated could still be carriers of the virus, even if they don’t get sick. So vaccinated people may get together with friends, family, and coworkers not vaccinated and spread it asymptomatically to all those not yet vaccinated

The benefits of getting the vaccine are of course significant, such as:

Those who get it, according to clinical trials, will probably have less severe disease than those who didn’t
Elderly individuals and those with chronic medical conditions have a much elevated risk of severe illness and death, and the vaccine will substantially reduce these outcomes
It will put less strain on the health system, frontline health workers, and first responders

However, these benefits may not be enough to persuade people to get vaccinated when their own fears or others’ fears or biases spread to them rather than the facts and logical reasoning.

The bottom line is that even if all these vaccine issues are reasonably addressed, there will still be shortcomings to vault over in the near-term.

One means to bridge this gap are other preventive measures. We know that masks can quickly be nearly 70% effective in preventing the spread of Covid-19 [26]. However, their problems have been:

It takes everyone wearing a mask at all times to achieve that level of protection
It requires proper wearing of the mask, such as not letting it slip below one’s nose
It requires proper cleaning for reusable masks, or constant (and costlier) replacement of disposable ones

If we wanted to find another way to reduce viral contagiousness by 70%, what would that entail?

It would require reducing the number of people infected when in proximity to those afflicted, and also potentially reducing the viral load inhaled by a person (given problem that respiratory droplets can hover in the air for 14 minutes or more even from simply talking [27]). Viral loads have been shown in peer-reviewed studies to be a prime determinant of how severe a case of Covid-19 will be that a patient must endure or will lead to death [28]. This could be done by reducing time in the air and possibly the distance traveled for the contagious respiratory droplets. To become ubiquitous, it would have to be an economical solution as well, one requiring only common household items.

And if we attained this 70% level, how many lives could be saved? Well, if 2021 will at least be as bad as 2020, then reducing by 70% the 300,000 deaths we saw in 2020 would be over 200,000 lives saved from Covid-19 alone — but then also prevent deaths from respiratory infection, which in normal years is still in the top 5 killers in the U.S. [29]. That does not even include the new variants we can expect, or the new pandemic threats emerging more frequently than we expected, given unsettling trends noted by experts [30].

So our challenge is reaching 70% protection effectiveness, but in a “better, faster, cheaper” way.

To develop a solution, though, it is important first to understand the problem. We must realize that we have the most total deaths and one of the highest rates of mortality in the world — the U.S. has been more impacted by Covid-19, and therefore likely more susceptible to severe or deadlier versions to it here versus other nations like South Korea That is because Covid-19 tends to affect older populations and also more diseased populations. In states like Pennsylvania, Michigan, and even Canada and Europe, populations tend to be older, based on median age [31]. Moreover, older populations also tend to have more chronic disease conditions. All of these lead to greater deaths [32]. Relatedly, we may have experienced or witnessed older people having more memory issues — a simple fact of life — and that leads to more resistance to changes in habits and learning new tasks, as well as the anxiety during a pandemic leading to missed tasks [33]. So practices such as constant, proper mask-wearing and social-distancing become challenging.

All of this has led to Covid-19 becoming the leading cause of death in the U.S. in the past year — over 1 in 1000 deaths, and when we look at how quickly it happened [34], it shows why we are in such danger from these new mutations of the virus for Covid-19.

Furthermore, it is not just lives and health. When we consider impact, we should consider return on investment, meaning how much savings is there from fixing a problem versus the level of investment needed for solving the problem. A solution that can offer protection over masks and vaccines could impact entire industries in our economy, like restaurants, bars, and hospitality, saving jobs and businesses. For example, restaurants economic devastation in a little over the month of April 2020 of the lockdown was nearly 6 million jobs lost in the U.S. alone [35]. And for the first time since the once-assumed pandemic recovery, the U.S. has now begun losing jobs again [36], as it already had in Canada last month [37].

In fact, given that economics today relies on trade (not just for export markets, but also for supply chains to make items that we sell to ourselves or other nations), we must consider how to maintain trade that use essential workers at risk of contracting or spreading Covid-19 between populations. One example is the trade between the largest export trading partners of the U.S., which are Canada and Mexico. However, given the winter temperatures and humidity levels, it may be that protecting essential workers involved in Canadian trade (e.g., truck drivers) that is most important to protect from Covid-19. In November, when North Dakota was the worst Covid-19 hot spot in the U.S. [38], very soon after, Winnipeg, Manitoba became one of the worst hot spots in Canada [39], and they share a major port of entry at their border. It could be unrelated, but given the traffic of essential workers and goods, there is a good chance that human behavior is involved, and likely the fastest solution, and there are the similar demographics, climate, and likely resource constraints that mean they can face similar growth trends quickly with any new outbreak.

Furthermore, at least 32 more countries have found the more contagious virus variant first seen in Britain [40]. With air travel not just a key industry, but also a an important component of economic activity, it will be important to restore flights, but also prevent it from being a major vector for Covid-19’s spread.

The bottom line is that if we do not take measures that slow the spread enough for the vaccine to catch up, we will see worse economic impact and increasing levels of job losses not just from demand reducing as people stay home to avoid getting ill, but also as economic activity is impeded from trade and travel.

Overall, the trends are not in our favor already, but we could go full-bore “frying pan into the fire” stunningly quickly unless a realistic community-wide solution is found as soon as possible. Of course, as they say, things could go better than we expect — but only if our luck changes. And it would be the triumph of hope over experience, based on the course of this pandemic.

STEP 1: The Key to a “Better, Faster, Cheaper” Solution (for Education Minute 1’s first 30 seconds)

Do we have to wait for luck and rely on hope? Not when we have the ability to reduce the threat to ourselves, and can help people take immediate control of their own destiny. A cost-effective shortcut to quickly achieve up to a 70% reduction in threat of Covid-19 for many can be accomplished by simply harnessing basic biology, physics, math, and of course scientific studies available online — that is, basic science and math. In so doing, this effort can also harness the power of youth and students to help achieve the solution throughout the community (e.g., especially if promoted by local to national governments as an educational community service initiative).

Moreover, this solution potentially achieves the 70% level of viral load reduction just as an initial dose of vaccine or effective mask-wearing would do, and thus could prevent 200,000 deaths in the U.S., and again, given our concern for both people and economics,10,000 deaths in our aforementioned neighbor, largest export market, and strategic ally, Canada [41]. Subsequently, hundreds of thousands more lives and livelihoods can be saved around the world.

The solution is simple: There is a common finding from our scientific research on infection and climate data Covid-19 epicenters since March of 2020. It showed that optimal levels of humidity at key periods when people may be most in contact with one another, or perhaps least aware of their risks, were a likely factor — and thus part of the solution.

Our research, when coupled with others’ research on the benefits of humidity [42], show that optimizing moisture levels in the air have significant preventative benefits, including reducing the deep penetration of viral loads that reach the bottom of the lungs, and for not just Covid-19 but other viruses and bacteria.

The main challenges, however, were:

1. How to tell if the humidity levels in whatever location you were at, especially if you just arrived, were in an optimal range

2. If the levels were not optimal, how could you change it both quickly and cost-effectively

Moreover, the key to solving these challenges will be getting people to:

1. Understand what to do quickly

2. Enable the least resistance to adoption

3. Ensure reliable adherence to the checklist at all times

For point #3 above, one approach we have found that maximizes the checklist adherence is by making tasks simple for people, framing it with what they have likely already seen and understood in the past. High reliability is important, since the virus is always looking for an opening.

Though not as effective as a mask, humidity is certainly much easier for universal compliance in an indoor workplace or gathering than ensuring everyone is wearing a mask properly at all times (including eating and drinking), and thus disproportionately beneficial to prevention versus the cost and effort needed.

In writing this article, we set out to describe each recommended principle, why it is being recommended (e.g., virus transmission factors), and how it can be implemented in the quickest and least expensive manner. Moreover, our recommended checklist tasks have minimal or negligible costs. While their efficacy has not yet been proven in peer reviewed studies, they differ significantly from other unproven solutions (e.g., Hydroxycholoroquine) because their trade-off costs, side effects, and mortality risks are comparatively low. In other words, even if they are not absolute wins, they are comparatively cost-effective.

Step 2: Understand Why Humidity (for Education Minute 1’s last 30 seconds)

First a primer, if one is needed (else, just skip ahead a few paragraphs). Humidity refers to the amount of water vapor present in the air. A relative humidity of 100% would mean that the air itself is saturated, or unable to hold any more water vapor. The higher the temperature, the higher amount of water the air can hold [43].

Absolute humidity (expressed as grams of water vapor per cubic meter volume of air) is a measure of the actual amount of water vapor (moisture) in the air, regardless of the air’s temperature. The higher the amount of water vapor, the higher the absolute humidity. For example, a maximum of about 30 grams of water vapor can exist in a cubic meter volume of air with a temperature in the mid-80s. Relative humidity (RH) (expressed as a percent) also measures water vapor, but relative to the temperature of the air. It is a measure of the actual amount of water vapor in the air compared to the total amount of vapor that can exist in the air at its current temperature. Warm air can possess more water vapor (moisture) than cold air, so with the same amount of absolute/specific humidity, air will have a higher relative humidity if the air is cooler, and a lower relative humidity if the air is warmer. What people “feel” outside is the actual amount of moisture (absolute humidity) in the air [44].

The ability of the air to hold water depends on its temperature. For example, a given volume of air at 20°C (68°F) can hold twice the amount of water vapor than at 10°C (50°F) [45]. Also, if confronting altitude, it should be noted that relative humidity decreases linearly with an increase in altitude at an average of 4% per kilometer, so not as large an impact as seasonal or daily weather can impact the relative humidity percentage [46].

Our researchers’ work with the U.S. Army’s Telemedicine and Advanced Technology Research Center (TATRC) and the U.S. Air Force (USAF) concentrated on creating and increasing the effectiveness of safety checklists, including infection control during the 2014 Ebola pandemic. In March of 2020, we applied this ability to analyze and help control infections and prevent deaths to SARS-CoV-2 (the virus responsible for Covid-19), focusing on simple safety checklist tasks that could have a high return on invested effort.

The first safety checklist was in aviation by what would become the U.S. Air Force, and was to improve flight safety as a result of a bomber crash in 1935 [47]. The purpose of a safety checklist is often just an easily followed set of steps that give a better, faster, and cheaper solution to immediately save lives, if it can be socialized, learned, and executed reliably by as many people throughout the community as possible.

When we first started examining all the series of epicenters for Covid-19 in March (Wuhan, Tehran, Lombardy, New York City, and others), each seemed — at their peaks — to have had an average daytime high temperature of 50 degrees Fahrenheit (10 degree Celsius) and 30 degrees Fahrenheit at night. The very cold cities (e.g., below 25 degrees Fahrenheit) seemed to be less affected, likely because people went outside to visit stores and people less. But they also all seemed to have the common factor of lower humidity levels at the time of their outbreaks.

The evidence inspired a hypothesis of the increasing infections now being seen in California hospitals, especially Los Angeles, but also helped predict Arizona becoming an epicenter in late Spring over the Summer (when the relative humidity of the air was less than 10%), and Florida getting worse in the Summer versus the death rates seen in the Spring. The reasoning was there would be drier air wherever people were meeting each other, whether at workplaces, air conditioned malls and restaurants, and even the climate controlled healthcare facilities they were all visiting. And this past summer’s surge was without schools being open to enable the virus to spread faster to the community at large, even if it was in a group less at risk (though not immune) from its worst effects.

So we had a hypothesis, and some data to support it. Next we needed the reasoning to see if it made sense. What could be the advantage of something as simple as water in the air?

First of all, humidity enables our body’s first line of defense — mucus — to work against any microbe. However, in low humidity settings, our mucus dries out [48]. Mucous membranes (or mucosa) coat various parts of the human body, but to protect against SARS-CoV-2 virus, none are more important than the respiratory tract.

The mucosa depletion risk is reduced the higher the humidity. What this means is that there may be additional benefits to wearing facial masks than just impeding airborne respiratory droplets. Logic would dictate that masks help reduce moisture leaving the body (as steamed glasses indicate when wearing a mask). Moreover, anecdotal evidence (though scientifically rigorous study is required) has shown increased moisture retention of the respiratory system at a person’s mouth based on mask usage versus no mask usage when using a crude hygrometer measurement system.

Drying of mucus will be higher at higher temperatures given the same amount of water evaporated into the air, so it will take more water to make it safer to not dry membranes. Drying is also known as evaporation. The rate at which water evaporates depends upon several factors, including the temperature, relative humidity and air flow rate. Water evaporates very fast when it’s exposed to hot, dry fast moving air. Conversely water evaporates very slowly when it’s in cold, damp still air.

Air flow rate is also important, because as water evaporates, the layer of air above the water (or damp concrete) gradually becomes more saturated with water vapor. When evaporated moisture levels reach saturation drying essentially stops. Air flow increases the evaporation rate by “flushing” away the stagnant moist air above. If a surface is at 100% relative humidity it doesn’t matter how long you “dry” it — it won’t lose moisture and dry out because the air surrounding it can’t hold any more moisture [49].

However, for other benefits of humidity, it may be absolute humidity and moisture content of the air that is more important. For example, consider fluid dynamics of droplets spreading and hovering. Research shows that air moisture may envelope small respiratory droplets, making them larger and heavier, letting them fall to the floor, where they are much less likely to infect. It could also dilute the viral load in the respiratory droplets, or may make those droplets too big to not only hover but to also make into someone else’s mask.

Moreover, humidity, for various viruses including flu, appears to “deactivate” the infectiousness of the virus dramatically. For example, in one study on flu viruses, to simulate flu transmission in a health care setting, researchers used “coughing” and “breathing” mannequins that were placed about 6 feet apart. Flu virus particles were released during a “cough,” and devices throughout the room and near each “breathing” mannequin’s mouth captured the particles. The particles were then collected and tested for their ability to infect human cells. At humidity levels of 23%, 70 to 77% of the flu virus particles were still able to cause an infection an hour after the coughing simulation. But when humidity levels were raised to 43%, just 14% of the virus particles had the ability to infect. Most of the flu particles became inactive 15 minutes after they were released into the humid air. “The [flu] virus just falls apart,” at high humidity levels, said a study researcher at the CDC’s National Institute for Occupational Safety and Health [50]. Although the study noted above was for a flu virus, it may apply as well to a coronavirus, at least in terms of results.

The 70–77% infectiousness at 23% humidity going down to 14% at 43% humidity noted above is a relative reduction of at least 80% (i.e., using a total of 70% pre-humidity infectiousness rate minus 14% post-humidity, then divided by the original 70%). Depending on the similarity to Covid-19 disease’s SARS-CoV-2 virus, this means we have one possible mechanism for a 70% reduction in viral infection, depending on how SARS-CoV-2 reacts to water. However, we believe it may not just be the structure of the virus that changes the ability for it to infect, but also the impact the higher humidity level has on having a more effective layer of mucus to trap and neutralize viruses (which mucus does effectively), which means this principle could perhaps lead to this level of protection and more readily apply to all viruses and bacteria.

One current, anecdotal example is that rural hospitals in the Mojave Desert of California are seeing nightmarish levels of Covid cases and deaths they are saying [51], and it is important to note that the relative humidity ranges during the daytime working hours are between 10% to 30% [52].

More empirical evidence (i.e. beyond anecdotal experience) appears to support this. In a state in India that was first affected by SARS-CoV-2 virus [53], more foreign nationals fell ill from Covid-19 than Indians. Indians’ homes are typically hotter and more humid than the offices/hotels of non-Indians. And though Indians contracted Covid-19, they appear to do so at slower rates of spread, relative to their population density, indicating that high humidity reduces, not eliminates, risk.

Another cross-check we did was compare the epicenters states like New York, New Jersey, and Arizona for their relatively lower humidity levels versus not only high population density but also higher humidity state of Florida in the U.S., then also Kerala in India. Then we contrasted the level of infection and mortality (given that severity of Covid-19 and thus likely mortality is heavily dependent on viral load according to studies). Our research has shown that even when population density is factored in, Florida and Kerala should have much higher case and death rates, but they do not. Humidity once again appears to be the key contributor to the advantage.

Once we believed that higher humidity levels were the key to higher safety, the challenge was in assuring that the desired level of humidity is attained quickly, while not doing a one-size fits all approach in a location, since higher heat and humidity can increase bacterial and mold growth.

Below is a graph of the “sweet spot” for humidity to enhance health, a range between 50% and 60% being best, and below 40% being a significant virus risk and above 70% being a significant mold risk (it is important to remember the <40%, 50%, and >70% thresholds).[54]

The risks could still be high during the spring as well. There could also be an acceleration of cases (i.e., an even more upward inflection point in the number of people infected curve) due to the loss of the polar vortex [55], which meteorologists expect will increase the temperature fluctuations over at least the next month. Experts opine that this loss favors wild temperature swings and severe weather over the Lower 48 of the U.S. As we have seen locally in Pittsburgh, this scenario has led to stronger, more chilling winds and also temperature declines of up to 50 degrees within 36 hours on certain days.

These large temperature swings present two problems related to the immune response of humans. As noted in a Harvard publication, some of this may have to do with a few infectious organisms, like flu viruses, thriving in colder temperatures.

But there is also evidence that sudden exposure to cold temperatures (e.g., the proverbial “draft”) suppresses humans’ immune system, so the opportunities for infection increase. A study published in The New England Journal of Medicine in the late 1970s famously debunked the belief that the common cold is linked to [simply] cold exposure, but British cold researchers have maintained that there is a cold–to–common cold connection. Their hypothesis is that cold air rushing into the nasal passages makes infections more probable by diminishing the local immune response in the nose [56]. Yale University has also found when the core body temperature inside the nose falls by 5 degrees Celsius (i.e., 9 degrees Fahrenheit), the immune system does not work as well to fight at least the cold virus [57]. The anticipated wild swings in temperature may also mean many more remaining days in April and even May of days being cold, requiring indoor heating. Conversely, temperature swings may also return as early as the fall (so September) — leading to the humidity challenge noted as important in our checklist.

It is important to note that the presence of higher humidity, while it may reduce infectiousness, indeed does not bring the infectiousness down to zero. There remains a clear risk of transmission, both in India, given its population density, and in Florida, because of its older demographics, as was shown as 2020 progressed.

Step 3: Monitoring Cost-Effectively (for Education Minute 2)

In our original research conducted in March, we had noted that relative humidity levels should be constantly measured by hygrometer to ensure these levels are maintained. These devices are available on online retailers and relatively inexpensive, typically costing less than $10. However, what’s different from this original research using hygrometers is that now there is no need for a hygrometer to be purchased or carried to wherever people may travel.

The reason for this shift included not just affordability during a pandemic and a lack of time and motivation given all the stresses, but also the difficulty we have experienced trying to educate the elderly and also the less informed of what to get (e.g., some kept reverting to calling the hygrometers thermometers — then going on to buy thermometers). It is also worth noting that one can make a hygrometer [58], but then would need 2 thermometers and would require multiple steps that would take us beyond the 3 minute process we wanted to recommend people learn.

In other words, most were unfamiliar with the term “hygrometer”, so we wanted to rely on concepts and terms most, including the elderly, as they are most at risk, would be able to learn, remember, and do.

Thus, our solution is to try and ensure people are aware of whether they are in a less than 40% humidity, or an optimal (based on the evidence) of 50% relative humidity, or finally a mold-risk level of 70% is simple — static shocks and glasses “sweating”. Most would likely remember the names and effects of static electricity and water condensation on a glass. And we need to be able to know about the degree of risk when you don’t have a hygrometer conveniently at hand.

For example, when the outside temperature drops below 20° F, even an indoor humidity level of 30% can lead to condensation on windows, doors or other cold surfaces [59].

So here is the simple checklist for monitoring humidity: If you need to know the humidity quickly and don’t have, or cannot find, an indoor hygrometer that has preferably been stationary in the room for at least 2 minutes that you can sit by, then — while wearing your mask until humidity is testing at minimum levels of 50% relative humidity — do one or more of these steps to see if an area may be unsafe:

Check for static shocks by shuffling across carpets in your shoes or preferably socks for 30 seconds and touching something metal to see if you detect a shock if in a carpeted room at a home, apartment, or work (since at greater than 40% relative humidity, the water vapor basically “short circuits” the static electricity) [60], or…
Bring a small piece of plastic wrap (e.g., if you are in a waiting room, school, or a place of leisure like theater or restaurant), then rub it against a wool sweater, suit, or any other wool clothing, even wool socks or your hair worst case, for 15 seconds and then see if it is attracted to a wall or attracts strands of your hair [60], or…
Get a glass of cold tap water (i.e., typically 50 degrees Fahrenheit) or a can of any refrigerated beverage (i.e., typically 45 degrees Fahrenheit), to see if it “sweats” (i.e., develops condensation) within 3 minutes or less [61]

If no dew forms on the glass or can, then your relative humidity is likely under the safer 50% level, while if your test reveals static electricity or shocks, it means it is under 40%, Either scenario should be an immediate warning to get on your mask to cover your nose and mouth, and to start raising humidity as described in the next section.

However, to see if an area already has safe levels of humidity, then do one of the following:

If you walk into a room and see dew on the inside of a window, that usually means the relative humidity is adequate (at least if it is under 50 degrees Fahrenheit outside, and inside it is around 70 degrees Fahrenheit inside, given the dew point of 50% humidity at those temperatures) [62], or…
Do the cold beverage test as described above in #3

If you are seeing dew on the window, or the glass of cold tap water or can of any refrigerated beverage is sweating, you are much more likely to be in a safe zone with adequate humidity.

Finally, to see if an area has excess levels of humidity (i.e., above 70%), then do:

A tap water mixture of 4/5ths of a glass of cold water, and 1/5th hot (i.e., typically 120 degrees Fahrenheit) to see if condensation still forms within 3 minutes, in which case the humidity level is likely too high and must be adjusted downward as described in the next section [63]
Or, of course, you may be able to tell simply if your hair “explodes” with frizziness

Step 4: Adjusting Cost-Effectively (for Education Minute 3)

The next step in our safety checklist, after evaluating whether we are in a more safe humidity zone, is to modify the level to get us to that safer zone, when we are shown to be outside it from Step 3, of humidity. This is to protect at least our mucus membranes but hopefully air moisture for combatting contagious respiratory droplets. There are three approaches we considered:

Masks — for individuals that are about to interact with others who may be infectious (i.e., it cannot be ruled out that person they are meeting is not asymptomatic or infectious), masks can help –as they help us retain moisture and avoid drying of mucus membranes
Electric Humidifiers — here, only portable ones will do, since central heating humidifiers typically were not intended to reach the safe levels of relative humidity necessary for viral safety since they were more concerned about mold
Evaporative Humidifiers — these are non-electric and use simple water, cups, and tissue paper

For point #1, we suggested that — in order to build moisture in the respiratory tract — all persons that will be interacting in any area ensure that they are wearing their mask for at least 15 minutes prior to the in-person encounter, to build back the mucus along the respiratory tract.

For point #2, we have provided a graph [64] below showing the time necessary for various brands of portable humidifiers to reach key levels. But there are a few challenges. For example, Consumer Reports recommends cleaning portable humidifiers regularly to prevent mold growth, which can become an airborne allergen. And mold can grow in as little as 48 hours on wet surfaces. Also, the operating costs: Evaporative models deliver the most energy efficiency, since one can easily spend $350 per year to run four tabletop humidifier models; Compare this with about $30 for a single in-duct model [65].

If humidifiers are available, how an optimized humidity policy could be enacted and implemented in Home Health / Hospice at patients’ homes:

In the event patients do not have humidifiers they can move and set up before a home health visit, ask patients to boil water on their stove before the home health worker arrives, and have the home health worker measure the humidity with a portable hygrometer (or each patient can be given one, depending on cost constraints for the ~$20 device) before beginning high transmission risk interactions with the patient or their family
If commercial humidifiers are used, the amount of time to increase humidity from 25% to 45% is typically 2 hours [64]. But we believe boiling water should take approximately the same amount of time

So here is the simple checklist for managing humidity: If you need to raise the humidity quickly and don’t have, or cannot afford to run, a portable electric humidifier that has preferably been running for 2 hours before you arrive that you can sit by, then — while wearing your mask until humidity is testing at better levels from the steps in the prior section — do one or more of these steps:

Boil some water in an adjacent room (e.g., if you are at a house / apartment), or…–
Bring in a hot steaming beverage or soup to place near you continuously (e.g., if you are in a waiting room, or a place of leisure like theater or restaurant), or…
Quickly construct a simple evaporative humidifier by filling 3 cups of water, place on a waterproof surface, and hang from each cup 3 rolled up tissue papers, napkins, or paper towels half-dipped in the water and half-hanging over the side to allow water to soak and evaporate (e.g., if you are at work, school, or any place you will be for a longer time), based on fluid physics [66]. Typically it will take under two hours to get the humidity closer to the levels desired for the vicinity near the evaporator, but one can speed this up via air flow, especially warm air flow such as from a heating vent

However, if you need to lower the humidity from excess levels from your simple testing, then do one of the following:

If you have, and can afford to run, a dehumidifier or air conditioner, do that (e.g., at a house)
Otherwise, find and remove all sources of water vapor from boiling, steaming, damp drying items, and turn off electric humidifiers or empty simple evaporative humidifiers

Implementation Policies and Procedures

A checklist as simple as the 4-step process outlined in this article could easily be implemented by anyone in a home, but may be especially interesting, as noted previously, to students wanting to apply the knowledge they gained in science class to public safety community service, as well as to their own families, especially older parents and grandparents. However, given the rise in Covid-19 cases in the 18–34 age bracket [67], and the risk of “long haul” symptoms that last months or more, it is worth them applying it to their own classrooms and dorms, etc.

In parallel, this could be applied to other higher risk viral transmission hot spots such as:

Family caregivers tending to higher risk patients, such as elderly or chronic condition family members, including cancer treatment patients
Nursing homes
Emergency Department and Urgent Care Center Waiting Rooms
Home health staff tending to high risk patients and their families, as well as home health staff visiting households not taking proper precautions

How, for instance, can this be implemented in Hospitals/Nursing Homes/Other Healthcare Facilities? They could set up a “hot room” in the facility where healthcare workers interact with the patients in a space that has higher heat and at least 45%-50% humidity.

Moreover, given the pain currently happening again in restaurants, bars, and hotels [68], can use the technique in restaurants wear mask wearing is not possible, or wherever alcohol is served and compliance to best practices will almost certainly falter.

A new virus strain that led to new or extended lockdowns in the U.K. and Germany has been identified in the U.S., which risks spurring more restrictions that hinder hiring in the coming months. Those Americans getting vaccinated are essential workers or the elderly — people that either have already been working through the pandemic or are retired — which doesn’t lead to job gains in the immediate term [68].

What is also important to realize is that in the U.K. where this new variant was first found during the first lockdown in March, cases reduced by a factor of 10, and their new lockdown should be enough to slow growth. However, given the higher infectiousness of the new variant, it is very possible this will be not be enough to actually drive new cases down. The policies being recommended there focus first and foremost on authorities helping ensure people and workspaces are safe [69]. The biggest concern is that essential workers don’t have the option to stay at home and suffered higher mortality rates in the first wave, given:

Many are low-income workers who cannot afford to isolate if they develop symptoms or are a contact, and live in overcrowded housing where it is easy to infect others.
Many live in multigenerational housing, where they can infect older, more vulnerable people who are more likely to need hospital.
Many work in crowded, poorly ventilated spaces and are not empowered to demand better working conditions.

Finally, there is the threat of disinformation from groups that will be promoting false facts on preventive measures such as vaccines, which we have already seen with masks, and will be peddling unproven or even harmful cures. This diminishes the reliability of all the efforts, since best practices require people to actually practice them [70]. In addition, cognitive overload and the limits of mental processing capability crowds out rational thought and adhering to the extra precautions needed for safety even once vaccine is rolled out.

What will not be helping is that some will peddle (not just “anti-vaxxers”) the equivalent of drug (i.e., like crack cocaine or opioids) — of course there are a group of people who will actually seek and want believe disinformation due to brain psychology which is extremely challenging to overcome.

This is what went wrong with the polio vaccination for instance [71]. One example is in 2003, widespread rumors about polio vaccines intensified vaccine hesitancy in Nigeria. This led to a boycott of polio vaccination in parts of the country. The result was a five-fold increase in cases of polio in the country between 2003 and 2006. The boycott also contributed to polio epidemics across three continents. This is in spite of the fact that at polio’s peak in its own pandemic, it was paralyzing, as recently as 1988, at the start of a worldwide vaccine campaign, approximately 350,000 children each year. In 2018, after the vaccination campaign, the virus sickened just 33 [72].

Conclusion

An article in the New York Times noted this week that “as the coronavirus mutates, the world stumbles again to respond” and pointed out that we are “in a race against time.” [73]. Over one of every thousand people in the US has died of Covid-19 this year, and it could be surpassed in the coming year.

As denial of care starts happening more and more, the case fatality rates can only go up. To avoid that outcome, cities may need to go back into lockdown, leading to further economic devastation and social disruptions as people become more frustrated or apathetic to precautions. But as the U.K. is showing with its variant, even with lockdowns, the spread still appears to be severe.

Ergo, there needs to be an effective and rapid approach to address not only this new risk from these mutations, but also both new pandemic-level microbes and also respiratory infections that are among the top killers in a more normal year. These proposed steps, based on our research from literature searches as well as observations, empirical evidence, and scientific study, could be valuable to consider by not only individuals, but also public spaces and private businesses and organizations.

To recap, based on our research, the most important concept in our opinion: Monitor and manage humidity levels as cost-effectively and quickly as possible to avoid a new critical mass of public health and economic crises. And adding the steps outlined in the sections above to checklists items currently in use (e.g., social distancing, hand washing, wearing masks, etc.), is how this can be accomplished.

This recommendation addresses the concerns raised from our study of the epicenters of Covid-19 — that perhaps the drying of mucus membranes may be a significant risk to contracting Covid-19 (as Chile and Peru Covid-19 mortality rates illustrate, according to worldometer, given they have some of the driest air in the world in their mountains). Our research also showed that this is not just confined to winter — in summer was when Arizona, Texas, and Florida all started worsening, as people started going indoors for air conditioning (which typically is dehumidified for comfort) in public spaces like restaurants, movie theaters, and malls, as well as workplaces.

This loss of mucus membrane effectiveness could elevate the transmission risk between healthcare staff and patients and thus their potential to serve as vectors for the SARS-CoV-2 virus, and thus infect more persons in the community with Covid-19 disease. However, it goes far beyond healthcare staff and facilities. Any location where people — any of whom may be asymptomatic carriers, even those already vaccinated — may meet is a possible vector. Or even where people don’t meet, but are in an area where people have trafficked in the past 10 minutes.

It has been noted by health experts that States in the U.S. aren’t compensating for the prospect of 5,000 deaths or more a day by doing the compensatory restrictions and lockdowns for fear of further devastation to their economies [74], so something else is needed. The approach we have outlined in this article can help compensate for multiple risks we have described, both within our control (e.g., mask wearing, vaccine acceptance) and also outside of our control (e.g., viral mutations).

It can also be an approach that one single person can do to help many people at once, since as humidity spreads it can envelope a crowd like a partial “security blanket”, and it relies less on personal responsibility and has greater “fault tolerance” that can compensate for those members of the public resistant to, or incapable of, always following the other safety protocols such as masks. One analogy we have employed is that the door only has to be unlocked once for the burglar to break into your car — and, similarly, this virus is always probing every door of every person’s immune system, looking to see which are unlocked.

The objective of this current research was to determine how to bring safety to those who can’t afford the $50 for the devices of a hygrometer and humidifier (e.g., those who are unemployed or food insecure may value food more than tools), can’t tote the devices along, or simply can’t seem to find the time to get devices or follow all the many safety precautions available. We believed this could be over half the population. And if we may now be facing a 70% higher transmission rate, vaccinations will have an even harder time keeping up with infection rates, assuming the approved vaccinations can still maintain their effectiveness with mutations, which is not a given.

Though this solution could be important for all of North America (since there are mountains and thus drier areas in Mexico also), it could be especially critical in the U.S. and Canada. This is because of the low temperatures and risk of drier indoor air this coming winter. Given the possible 70% relative reduction in viral transmission, this could reduce viral load, and thus the severity of illness and mortality risk. As a result, compliance to humidification could save 200,000 lives in the U.S., 10,000 in Canada, and more all over the world. It can also prevent lockdowns that lead to financial calamity, and millions of lost wages, jobs, businesses, and tax base.

Until Mother Nature can weaken the virus or the government can improve its pandemic response, we will need to rely on ourselves to protect ourselves, using basic science that can be heard in most high school and college science classrooms and explained by our students — if we choose to listen and learn.

ACKNOWLEDGEMENTS

The High Reliability Organization Council (HROC) team, for its research contributions to this article. Greg Cioffi of HROC specifically for his assistance on graphics and visuals. Reilly Odom, Ryan Odom, who are two high school students helping teach people the IMI checklist,and helping on data / chart interpretations, calculations, table development, and policy suggestions.

REFERENCES / SUPPORTING DETAIL APPENDIX

[1] HROC research findings from research memo dated 3/24/20 and findings noted throughout this article and this appendix

[2] https://www.cnn.com/2021/01/13/health/pandemic-fatigue-vaccine-wellness/index.html ; https://www.self.com/story/biden-wearing-two-masks ; https://www.cdc.gov/coronavirus/2019-ncov/prevent-getting-sick/cloth-face-cover-guidance.html ; https://www.npr.org/sections/goatsandsoda/2020/11/03/929555568/coronavirus-faqs-are-3-masks-better-than-1-will-mouthwash-keep-you-safe

[3] https://www.worldometers.info/coronavirus/#countries; https://www.statista.com/chart/21305/projected-coronavirus-deaths-compared-to-historical-events/

[4] https://edition.cnn.com/world/live-news/coronavirus-pandemic-vaccine-updates-12-27-20/h_c8810a4ee2b923e6c70ebe1f2994be87

[5] https://www.washingtonpost.com/health/2021/01/07/covid-death-record/

[6] https://www.cnn.com/videos/health/2021/01/08/coronavirus-deaths-us-gupta-newday-vpx.cnn

[7] https://www.cnn.com/2021/01/05/us/los-angeles-county-california-human-disaster-covid/index.html

[8] https://www.cnn.com/2021/01/08/us/los-angles-county-covid-hospitals-crisis-ration-care/index.html

[9] https://www.cnn.com/world/live-news/coronavirus-pandemic-vaccine-updates-01-02-21/h_f297e473afd872b9d0736364e34f3ae1

[10] https://www.washingtonpost.com/health/2021/01/07/covid-death-record/

[11] https://www.wsj.com/articles/coronavirus-variant-in-south-africa-sparks-fear-of-faster-spread-possible-reinfection-11609358056

[12] https://www.cnn.com/world/live-news/coronavirus-pandemic-vaccine-updates-01-02-21/h_f297e473afd872b9d0736364e34f3ae1 ; https://www.theguardian.com/world/2020/dec/23/south-african-covid-19-variant-may-be-more-effective-at-spreading

[13] https://www.washingtonpost.com/health/2021/01/08/pfizer-vaccine-protection-virus-variants/

[14] https://www.washingtonpost.com/health/covid-variant-contagious-spread/2021/01/06/73a1b716-4fc2-11eb-83e3-322644d82356_story.html

[15] https://www.nbcnews.com/news/us-news/live-blog/2020-01-07-covid-live-updates-vaccine-news-n1253230

[16] https://globalnews.ca/news/7558741/coronavirus-uk-flight-ban-canada-end/

[17] https://www.theatlantic.com/science/archive/2020/12/virus-mutation-catastrophe/617531/

[18] https://www.mholland.com/news/covid-19-bulletin-march-31 ; https://statisticsbyjim.com/basics/coronavirus/

[19] https://www.washingtonpost.com/opinions/january-worst-covid-month/2021/01/08/7a8e12ba-51e6-11eb-bda4-615aaefd0555_story.html

[20] https://www.nytimes.com/live/2021/01/05/world/covid-19-coronavirus

[21] https://www.washingtonpost.com/opinions/january-worst-covid-month/2021/01/08/7a8e12ba-51e6-11eb-bda4-615aaefd0555_story.html

[22] https://www.france24.com/en/europe/20210102-amid-shortages-scientists-weigh-benefits-of-a-single-covid-19-doses-versus-two

[23] https://www.cnn.com/2021/01/10/health/grandparents-visits-covid-19-vaccine-wellnesss/index.html

[24] https://www.washingtonpost.com/opinions/2021/01/03/we-had-tools-fight-covid-19-before-it-arrived-next-time-we-might-not-be-so-lucky/

[25] https://www.cnn.com/2021/01/10/health/grandparents-visits-covid-19-vaccine-wellnesss/index.html

[26] https://www.nature.com/articles/d41586-020-02801-8 and add to Details 2

[27] https://www.nytimes.com/2020/05/14/health/coronavirus-infections.html

[28] https://www.bmj.com/content/371/bmj.m4763

[29] HROC research details 1

[30] https://www.washingtonpost.com/opinions/2021/01/03/we-had-tools-fight-covid-19-before-it-arrived-next-time-we-might-not-be-so-lucky/

[31] https://en.wikipedia.org/wiki/List_of_U.S._states_and_territories_by_median_age ; https://en.wikipedia.org/wiki/List_of_countries_by_median_age

[32] https://www.sepsis.org/news/the-connection-between-covid-19-sepsis-and-sepsis-survivors/

[33] HROC research details 1

[34] https://www.businessinsider.com/coronavirus-in-charts-covid-19-symptoms-spread-deaths-warnings-2020-2

[35] https://www.restaurantbusinessonline.com/financing/pandemic-has-cost-restaurants-59-million-jobs

[36] https://www.marketwatch.com/story/us-loses-140000-jobs-in-december-first-decline-in-eight-months-stems-from-record-coronavirus-surge-2021-01-08

[37] https://ca.finance.yahoo.com/news/canada-lost-63000-jobs-in-december-as-covid-19-cases-rise-133956373.html?guccounter=1&guce_referrer=aHR0cHM6Ly93d3cuZ29vZ2xlLmNvbS8&guce_referrer_sig=AQAAANu4K4TzbGoqGYaLMFkPWvte3_6XlEoBsFFaUKlfgWxWbipf7X__6THLyrbEGUAFZ5UXmFfM7Ub6BCT8lC0vHcippYT2JwvdxIilMV27A1xtWFSMWBJkrfmFjbWXPJWWJQY4j79h6QbWqN1AOfZiQUOYOQAOswhwHKciAYOgwJIo

[38] https://www.washingtonpost.com/opinions/2020/11/06/north-dakota-covid-19-cases/

[39] https://www.cbc.ca/news/canada/manitoba/manitoba-first-worst-pandemic-1.5793805

[40] https://www.nytimes.com/live/2021/01/01/world/covid-19-coronavirus-updates

[41] https://www.census.gov/foreign-trade/statistics/highlights/toppartners.html

[42] https://heavy.com/news/2020/03/humidifiers-stop-coronavirus-covid-symptoms-spread/ ; https://www.washingtonpost.com/opinions/2020/11/18/winter-covid-19-humidity/

[43] https://www.airthings.com/resources/everything-you-need-to-know-about-humidity#:~:text=In%20layman's%20terms%2C%20humidity%20refers,water%20vapor%2C%20so%20it%20rains.&text=The%20higher%20the%20temperature%2C%20the,water%20the%20air%20can%20hold

[44] https://www.weather.gov/lmk/humidity

[45] https://sealevel.jpl.nasa.gov/ocean-observation/understanding-climate/air-and-water

[46] https://www.researchgate.net/publication/313086856_An_Analysis_of_Altitude_Wind_and_Humidity_based_on_Long-term_Radiosonde_Data

[47] https://www.acc.af.mil/News/Article-Display/Article/200135/where-did-checklists-come-from/ ; https://www.airforcemag.com/article/0813checklist/ ; http://www.capitolreader.com/sum/040711-checklist.PDF

[48] https://www.sciencedaily.com/releases/2015/11/151106062716.htm — “White blood cells are among other places located in the oral mucosa, and they represent the body’s first line of defence against infectious agents.”

[49] https://concretecountertopinstitute.com/free-training/temperature-and-relative-humidity-what-they-mean-for-you-and-your-concrete-countertops/

[50] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3583861/

[51] https://www.cnn.com/videos/health/2021/01/09/covid-hellscape-california-hospital-ac360-sidner-pkg-vpx.cnn

[52] https://sciencing.com/humidity-mojave-desert-19526.html#:~:text=The%20humidity%20of%20the%20Mojave%20Desert%20changes%20throughout%20the%20day,as%20high%20as%2050%20percent

[53] (Analysis table that we can present of our findings and interviews)

[54] https://www.condair.com/m/0/2553856-a-hum-load-calculation.pdf

[55] https://www.washingtonpost.com/weather/2020/03/14/polar-vortex-spring-weather/

[56] https://www.health.harvard.edu/staying-healthy/out-in-the-cold

[57] https://nationalpost.com/health/why-do-we-catch-more-colds-when-the-temperature-drops-blame-our-immune-system

[58] https://www.wikihow.com/Make-a-Hygrometer

[59] Source https://www.physicsforums.com/threads/relative-humidity-in-my-house.274198/

[60] HROC research details 3