By Dr. Alondra Nelson, head of the White House Office of Science and Technology Policy and Deputy Assistant to the President
The most common way COVID-19 is transmitted from one person to another is through tiny airborne particles of the virus hanging in indoor air for minutes or hours after an infected person has been there. While there are various strategies for avoiding breathing that air – from remote work to masking – we can and should talk more about how to make indoor environments safer by filtering or cleaning air.
In fact, research shows changing the air in a room multiple times an hour with filtered or clean outdoor air – using a window fan, by using higher MERV filters in an Heating, Ventilation, and Air Conditioning (HVAC) system, using portable air cleaning devices, and even just opening a window – can reduce the risk of COVID-19 transmission – with studies showing five air changes an hour reduce transmission risk by 50 percent. 1,2 And, improving indoor air has benefits beyond COVID-19: it will reduce the risk of getting the flu, a common cold, or other diseases spread by air, and lead to better overall health outcomes.
The Biden-Harris Administration identified improved indoor air quality as an important tool to fight the spread of airborne diseases in the American Pandemic Preparedness Plan last September – and the National COVID-19 Preparedness Plan prioritized it again earlier this month. A number of Federal departments and agencies – including the White House Office of Science and Technology Policy (OSTP) – have worked together to launch the Clean Air in Buildings Challenge, a call to action for anyone who manages or maintains a building. As part of the launch, the Environmental Protection Agency released a practical guide for building managers, contractors, homeowners, and business owners to create an action plan for cleaner indoor air.
Now, we all need to work collectively to make our friends, family, neighbors, and coworkers aware of what we can do or ask for to make being indoors together safer. Each of us has a set of simple but powerful actions we can use to bring clean air into the rooms we’re in and clean the air already in the room.
Here are the basics:
- Ventilation: Bringing in clean outdoor air is key. Indoor air moves less than outdoor air, so virus particles hang in the air in greater concentrations. Ventilation strategies that bring in more outdoor air can disperse viral particles and lower the risk of people inhaling them or getting infected through their eyes, nose, or mouth. Fans and HVAC systems can help make open windows more effective by pulling in clean outdoor air, and can send clean air into rooms without windows or good ventilation. New buildings are often constructed to seal air in for energy efficiency, so their HVAC systems must be on or their windows opened to clear the air. Older buildings may be less well sealed, but have outdated air handling systems or lack them altogether. An HVAC expert can help with this; more resources are available here.
- Air filtration: Using high-quality air filters like HEPA or MERV-13 – connected to capable HVAC systems or portable air purifiers – to remove virus particles from indoor air is also important. Filtration is a great tool to supplement ventilation or to use if adequate ventilation isn’t possible – for example, if extreme temperatures, wildfire smoke, or outdoor pollution make you not want to open a window. And we need filtration equipment more than we might think: many schools, workplaces, hotels, and homes have windows that do not open at all. Many Americans and small businesses cannot afford major HVAC upgrades. While all of us can benefit, many Americans have health vulnerabilities and need the extra protection of having cleaner air. In all these cases, portable air cleaning devices with powerful fans – as powerful as a box fan you could buy at a store – can make a big difference in reducing virus particles in the air. HEPA filters, for instance, are at least 99.97% efficient at capturing human-generated viral particles associated withCOVID-19. As a temporary measure, there are affordable and effective DIY options, including the four-filter-plus-box-fan cube called the Corsi-Rosenthal box.
- Air disinfection: By inactivating (“killing”) airborne virus through methods like ultraviolet germicidal irradiation (UVGI) systems, we can add another layer of protection in indoor spaces. The latest technology in these UV lights is particularly useful in crowded areas with poor airflow, in healthcare settings with vulnerable populations (such as hospitals or nursing homes), or in areas like restaurants where people aren’t wearing masks because they’re eating and drinking. For instance, one study demonstrated that when used with proper ventilation, UVGI is about 80% effective against the spread of airborne tuberculosis, equivalent to replacing the air in an indoor room up to 24 times in an hour.  However, there are some challenges to doing this widely, and more research and innovation is needed to develop UVGI systems that are more affordable, standardized, and consume less energy.
Used along with layered prevention strategies recommended by Centers for Disease Control and Prevention and others, improving indoor air quality is a critical part of a plan to better protect us all. But it will not by itself eliminate the risk of infection: the best way to protect yourself against COVID-19 is to get vaccinated and boosted.
For decades, Americans have demanded that clean water flow from our taps and pollution limits be placed on our smokestacks and tailpipes. It is time for healthy and clean indoor air to also become an expectation for us all. Clean and healthy indoor air is a fundamental commitment we must make to our children, to workers, to those who are medically vulnerable, and to every person in the country.
Now we’re making it possible: Federal funds and resources are available to support improvements in ventilation, filtration, and clean indoor air – the American Rescue Plan has $122 billion for schools and $350 billion for state, local, and Tribal governments, which can support upgrades to their local businesses, nonprofits, community centers, and other commercial and public establishments. Additionally, the Bipartisan Infrastructure Law provides billions of dollars to our communities to support people’s health and safety in new or upgraded airports, transportation hubs, low-income housing, schools, and other buildings.
I am pleased to announce next we will be bringing experts from the fields of public health, the social sciences, engineering, and journalism together at a virtual White House event to learn more. Register here to join Let’s Clear the Air on COVID, which will kick off at 12:30pm on March 29th.
Scientific and public health evidence supports practical, actionable solutions for cleaner indoor air. It is time for a national conversation on how better indoor air quality can help us all live healthier lives.
 Rothamer, D.A., et al. Strategies to minimize SARS-CoV-2 transmission in classroom settings: combined impacts of ventilation and mask effective filtration efficiency. Science and Technology for the Built Environment, 27:9, 1181-1203 (2021). https://www.tandfonline.com/doi/full/10.1080/23744731.2021.1944665
 de Oliveira, P.M., et al. Evolution of spray and aerosol from respiratory releases: theoretical estimates for insight on viral transmission. Proceedings of the Royal Society A 477: 20200584 (2021). https://doi.org/10.1098/rspa.2020.0584
 Mphaphlele, Matsie et al. Institutional Tuberculosis Transmission. Controlled Trial of Upper Room Ultraviolet Air Disinfection: A Basis for New Dosing Guidelines. American J Respir Crit Care Med, 192(4), 477-4848 (2015). https://doi.org/10.1164/rccm.201501-0060OC
When used properly, air cleaners and HVAC filters can help reduce airborne contaminants including viruses in a building or small space. By itself, air cleaning or filtration is not enough to protect people from COVID-19.Does airing out your house help with Covid? ›
Ventilate your home by getting fresh air into your home, filtering the air that is there, and improving air flow. Improving ventilation can help you reduce virus particles in your home and keep COVID-19 from spreading.How do you remove air from Covid? ›
- Increase Ventilation with Outside Air.
- Improving Natural Ventilation.
- Use Your HVAC System and Consider Upgrading Filters.
- Use a Portable Air Cleaner if You Have One.
- Evaporative Coolers and Whole-House Fans.
Opening the windows is an easy and effective way to improve ventilation. Researchers at Harvard University found that if you open the windows in a room just six inches you can get 5 or more ACH with clean, outdoor air.How long is Covid in the air? ›
Infection with the COVID-19 virus may also occur if someone is exposed to very small droplets or aerosols that stay in the air for several minutes or hours.Do dogs get Covid? ›
The virus that causes COVID-19 can spread from people to animals during close contact. Pets worldwide, including cats and dogs, have been infected with the virus that causes COVID-19, mostly after close contact with people with COVID-19. The risk of pets spreading COVID-19 to people is low.Can you sleep in the same bed with someone who has Covid? ›
Protect yourself if you must share a bedroom with someone with COVID-19. Keep the window open if you must share a room. Keep beds at least 6 feet apart in shared rooms. Put a divider between beds in shared rooms.How long does coronavirus stay in the air 2022? ›
Another person can breathe in these aerosols and become infected with the virus. Aerosolized coronavirus can remain in the air for up to three hours.Does AC spread Covid? ›
With that said, coronavirus and air conditioning can be a potentially deadly combination, as air ducts and vents can be a safe space for the virus, even when the rest of the building is cleaned comprehensively.How long does Covid last on blankets? ›
A study published in found that at room temperature, COVID-19 was detectable on fabric for up to two days, compared to seven days for plastic and metal. However, when it was exposed to high heat, the virus became inactive within five minutes.
But to date, there's no evidence the virus can survive on clothing. However, health experts recommend following these laundry tips if you or someone in your household has or is suspected of having COVID-19: Wash and dry clothing and linens according to the manufacturer's instructions.How do I naturally purify the air in my house? ›
Here's a list of 6 natural ways to purify the air at home.
- Salt Crystal Lamp. ...
- Beeswax Candles. ...
- Houseplants. ...
- Activated Charcoal. ...
- Proper ventilation. ...
- Essential Oils.
They are typically the most reliable tests for people with or without symptoms. These tests detect viral genetic material, which may stay in your body for up to 90 days after you test positive. Therefore, you should not use a NAAT if you have tested positive in the last 90 days.Should I sleep with the window open if I have Covid? ›
Ventilation is most important if someone in your household has COVID-19, or when you have visitors in your home. Opening windows and doors is the easiest way of improving ventilation. Also open any window vents or grilles. Opening windows at opposite sides of the room or home is a good way of changing the air.How often should you open windows in your house? ›
So how often should you open your windows? It's recommended that you do so once a day, for at least five minutes. Fifteen to 20 minutes is preferable. However, when you open them is also important.Is Omicron airborne virus? ›
The rapid spread has raised concerns about Omicron being airborne, which leads to a high risk of contamination in public premises, particularly among the frontline healthcare workers. Mandatory usage of protective face masks and respirators is highly recommended in order to break the chain of transmission.Can you get Covid twice? ›
Reinfection with the virus that causes COVID-19 means a person was infected, recovered, and then later became infected again. After recovering from COVID-19, most individuals will have some protection from repeat infections. However, reinfections do occur after COVID-19.How long is Omicron contagious? ›
We know that people tend to be most infectious early in the course of their infection. With Omicron, most transmission occurs during the one to two days before onset of symptoms, and in the two to three days afterwards.Can dogs smell Covid? ›
Trained dogs seem able to detect acute COVID-19 about as well as a PCR test. But when it comes to long COVID, their accuracy has been harder to measure. Since there's no equivalent to a PCR test for long COVID, researchers can only compare the dogs' results to what patients say they're experiencing.Can dogs eat apples? ›
Yes, dogs can eat apples. Apples are an excellent source of vitamins A and C, as well as fiber for your dog. They are low in protein and fat, making them the perfect snack for senior dogs. Just be sure to remove the seeds and core first.
Strawberries are a healthy, low-calorie, sweet treat for your dog, full of antioxidants, high in fiber and vitamin C. Here's a bonus. By giving your dog strawberries, you are also helping him stay healthy in more ways than one.How do you make Covid heal faster? ›
- Keep a daily routine, such as taking a shower and getting dressed.
- Take breaks from COVID-19 news and social media.
- Eat healthy meals and drink plenty of fluids.
- Stay physically active.
- Get plenty of sleep.
- Avoid use of drugs, tobacco and alcohol.
Symptoms of Post-COVID fatigue generally mirror those of chronic fatigue syndrome. They can include physical, psychological, and behavioral complications, including: Persistent Tired and Sleepy Feeling. Mild to Severe Headaches.Does Covid make you sleep all day? ›
Extreme tiredness (fatigue) is common when you recover from coronavirus (COVID-19). Living with this symptom is difficult. It affects things that you would like to do, which can be frustrating.Can you have Covid and test negative? ›
A negative result means it's likely you are not infectious. But a negative test is not a guarantee you do not have COVID-19 and there's still a chance you may be infectious. You should follow advice on how to avoid catching and spreading the virus.How long does Omicron symptoms last? ›
How long do omicron symptoms last? Most people who test positive with any variant of COVID-19 typically experience some symptoms for a couple weeks.Is Covid airborne or droplet? ›
Yes, COVID-19 can spread via airborne transmission. When people with the COVID-19 infection breathe out, clear their throats, cough, sneeze, speak, or otherwise move air out through their nose or mouth, droplets of all different sizes, which can contain the virus, are ejected into the air.How quickly do Covid symptoms show? ›
Symptoms may appear 2-14 days after exposure to the virus. Anyone can have mild to severe symptoms. Possible symptoms include: Fever or chills.Can fans be used to decrease the risk of COVID-19 transmission indoors? ›
Can fans be used to decrease the risk of COVID-19 transmission indoors? Yes. While fans alone cannot make up for a lack of outdoor air, fans can be used to increase the effectiveness of open windows, as described in the CDC list of ventilation improvement considerations.How long does it take to air out a room? ›
Open the windows wide.
In the winter months, about 5 minutes is enough to provide our rooms with the right amount of fresh air.
You are considered contagious from two days before your symptoms begin until 10 days after your symptoms began. If you have no symptoms, you are considered contagious beginning two days before your test sample was collected and until 10 days after your test sample was collected.How long after Covid are you contagious? ›
People are most contagious with COVID-19 during the first 5 days of their illness. Many people don't have any symptoms during the first 2 to 3 days of their illness. This is why COVID-19 outbreaks are so hard to contain. On average, people are contagious for 5 to 10 days.How long does coronavirus live on food in the refrigerator? ›
Researchers found that both lower temperatures and lower humidity helped viruses survive longer. In particular, at 4 degrees C, or 40 degrees F, and 20% relative humidity, more than two thirds of the viruses survived for 28 days.Does vinegar purify the air? ›
So, does boiling vinegar actually clean the air? The short answer is no, as far as current scientific research is concerned. Acetic acid, the active component of vinegar, is capable of killing pathogens, but only through direct contact.Does baking soda purify air? ›
From fridges to bathrooms, a simple bowl of baking soda will help you to quickly and easily purify air in the home. For best results, leave the bowl of baking soda sit for several hours, or until you notice the smell is gone.What can I buy to purify the air in my house? ›
Invest in an air purifier
Enter the air purifier. The best air purifying machines trap and remove almost 100% of pollutants by drawing in dirty air, filtering it and releasing it back out into the room, much cleaner and fresher.
If you are significantly immunosuppressed, you are more likely to be infectious for longer than 7 days and may still be able to spread the virus. Follow these measures until day 14 following your positive test result to further reduce any remaining risk of spreading the virus.Are you still contagious after 10 days of Covid? ›
Those with severe COVID-19 may remain infectious beyond 10 days and may need to extend isolation for up to 20 days. People who are moderately or severely immunocompromised should isolate through at least day 20.Why do I keep testing positive for Covid? ›
Positive COVID-19 Test: A Sign of Viral Shedding
Viral shedding is the release of a virus as it multiplies inside your body. If you are shedding virus, it means you can pass it on and infect other people. Testing positive for COVID-19 is an indication of viral shedding.
Ensuring proper ventilation with outside air can help reduce the concentration of airborne contaminants, including viruses, indoors. Proper ventilation also reduces surface contamination by removing some virus particles before they can fall out of the air and land on surfaces.
When used properly, air cleaners and HVAC filters can help reduce airborne contaminants including viruses in a building or small space. By itself, air cleaning or filtration is not enough to protect people from COVID-19.How can I ventilate a room without a window? ›
- Air Conditioning. ...
- Extractor fans. ...
- Grills or ventilation fans between rooms. ...
- Temporary ducts. ...
- Leaving doors open. ...
- Fans. ...
- Perforated building materials. ...
- Portable Evaporative Coolers.
The study found that opening windows and doors improved ventilation and airflow in bedrooms. It improved the quality of sleep in 17 healthy participants. “What we expected to observe was that lower ventilation levels would negatively affect sleep.Why should you not leave a window open at night? ›
Sleeping with the window open could inadvertently trigger allergies, asthma or potentially cause illness in someone with an already-weakened immune system. But for most people, it's relatively risk free. Aim to keep your bedroom around 65 degrees with 65 percent humidity.Why you should leave your window open at night? ›
Open windows may help you sleep better
Most people find that nighttime outdoor sounds have a relaxing effect on them, so let nature's white noise take over when the nights are cool enough for open windows.
Why You Should Open Your Windows During Coronavirus
Open the windows! A guide to airing your house and Covid-19
Open a window: It's the best thing you can do for your health when ...
Options for providing enhanced respiratory support include using high-flow nasal canula (HFNC) oxygen, noninvasive ventilation (NIV), intubation and mechanical ventilation, or extracorporeal membrane oxygenation.What is the best decongestant for Covid? ›
- DayQuil. DayQuil combination OTC products usually contain acetaminophen (for fever and pain), dextromethorphan (for coughing fits), and phenylephrine (for stuffy nose).
- Mucinex. ...
- NyQuil. ...
- Sudafed. ...
How long do omicron symptoms last? Most people who test positive with any variant of COVID-19 typically experience some symptoms for a couple weeks.What do you drink Covid with? ›
Up your fluid intake.
If you have diarrhea or if you're sweating from a fever or chills, make sure you have salt or a little sugar in your fluids—think broths, fresh juices or electrolyte solutions like Gatorade—because salt and sugar can help you retain water.
As long as hospitals aren't overwhelmed, the survival rate for COVID pneumonia is about 80%.What is a good oxygen level with Covid? ›
A normal level of oxygen is usually 95% or higher. Some people with chronic lung disease or sleep apnea can have normal levels around 90%. The “SpO2” reading on a pulse oximeter shows the percentage of oxygen in someone's blood. If your home SpO2 reading is lower than 95%, call your health care provider.How long after testing positive for Covid are you contagious? ›
People are most contagious with COVID-19 during the first 5 days of their illness. Many people don't have any symptoms during the first 2 to 3 days of their illness. This is why COVID-19 outbreaks are so hard to contain. On average, people are contagious for 5 to 10 days.How do I stop a Covid cough? ›
“You can try to control your cough with over-the-counter cough medicine.” Staying hydrated will also help your body clear your airways and encourage healing. If you have a lingering cough from COVID-19 and notice that it's lasted longer than a month or is worsening, talk to your doctor.
Use a hot shower, humidifier, vaporizer or other means of making steam. It will soothe a sore throat and open your airways, making it easier to breathe. Eat a frozen treat. The coldness may help numb the pain and soothe your throat if it is sore from coughing.Is mucinex OK for Covid? ›
Managing Cough and Shortness of Breath
Over-the-counter medications used for upper respiratory infections may help alleviate symptoms. Those medications include guaifenesin (Mucinex), pseudoephedrine (Sudafed), and dextromethorphan (Robitussin, Delsym).
Reinfection with the virus that causes COVID-19 means a person was infected, recovered, and then later became infected again. After recovering from COVID-19, most individuals will have some protection from repeat infections. However, reinfections do occur after COVID-19.Does Covid get better after 5 days? ›
If you test positive for COVID-19 and have no symptoms – you may end after day 5. If you test positive for COVID-19 and have symptoms – you may end after day 5 if: You are fever-free for 24 hours (without the use of fever-reducing medication) Your symptoms are improving.How quickly does Omicron show up? ›
The time from exposure to symptom onset (known as the incubation period) is thought to be two to 14 days. Symptoms typically appeared within five days for early variants, and within four days for the Delta variant. The incubation period appears to be even shorter – about three days – for the Omicron variant.What helps Covid recovery? ›
Treating a high temperature
- get lots of rest.
- drink plenty of fluids (water is best) to avoid dehydration – drink enough so your pee is light yellow and clear.
- take paracetamol or ibuprofen if you feel uncomfortable.
Due to the increased stress from COVID-19, you need more calories than your normal diet. Try to eat 75-100 grams of protein per day which is 10-14 ounces of a protein source. Good protein sources are: peanut or nut butters, milk, eggs, yogurt, cheese, meat/fish/poultry, protein shakes.How can I boost my immune system after Covid recovery? ›
- Boost the Immune System.
- Getting Good Sleep.
- Healthy Eating.
- Stress Management.
- Quit Smoking.