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Prevention in
Public Places

COVID-19: Reducing Risk

Keeping Safe & Preventing Spread


The COVID-19 virus continues to spread, especially to those who are not fully vaccinated. The more contagious Delta variant is now widespread in LA County.

The following information is to help people understand who is most at risk of getting infected and sick, which situations are riskier, and what steps they can take to stay safe and slow the spread of COVID-19.

To learn about the rules that must be followed in public settings, including when you need to wear a mask or show proof of vaccination or a negative test, visit the COVID-19 Prevention in Public Settings webpage


People who are not vaccinated are at the highest risk of getting infected with COVID-19. This includes people who have not completed their Pfizer or Moderna COVID-19 vaccine series (i.e., they only got the first dose) as well as children who are too young to be vaccinated. Unvaccinated adults who are older or who have certain medical conditions are at highest risk of severe COVID-19 disease.

People with severely weakened immune systems who are fully vaccinated might not respond as well to the vaccine so may still be at increased risk of COVID-19, even after receiving additional doses of vaccine.

Fully vaccinated persons are at lowest risk of getting infected with COVID-19. They are well protected from getting very sick and dying from COVID-19. A small percent of people who are fully vaccinated are getting infected with the Delta variant of the COVID-19 virus. These “breakthrough infections” are expected even with highly effective vaccines. Importantly, breakthrough infections usually cause mild symptoms, if any. It is possible for fully vaccinated people to spread the virus to other people.


Understanding how the COVID-19 virus is spread is important. It will help you to assess your risk and take steps to protect yourself in different situations.

The virus spreads from person to person mainly through respiratory droplets that are released into the air by a person who has COVID-19. For example, when they speak, sing, cough, shout, sneeze, or breathe heavily. These droplets are then breathed in by other people or land on their eyes, nose, or mouth. A person’s risk of getting infected goes up the closer they are to someone with COVID-19. Enclosed places with poor air flow can also increase the risk of getting infected. This is because the droplets that have the virus can concentrate and spread in the air past 6 feet. They can even stay floating in the air after an infected person has left the room.

This is why masks are important. They lower the number of respiratory droplets people release into the air AND also the number that they breathe in.

It is also possible, but less common, for the virus to spread by touching a surface with droplets on it and then touching your eyes, nose, or mouth.

There are certain places where COVID-19 spreads more easily

  • Closed spaces with poor air flow.
  • Crowded places with many people nearby
  • Close contact settings especially where people are talking (or breathing heavily) close together


  • Get vaccinated. It is the best way to protect against COVID-19 (see Vaccination below)
  • Wear a mask that fits and filters well. Your mask is one of the most powerful tools you have to protect yourself and other unvaccinated people (see Masks below)
  • Avoid crowded places. Being in crowds, especially indoors, puts you at a higher risk. If you need to be indoors, try to go during non-peak hours and consider wearing a more protective mask. Limit how long you are there.
  • Improve air flow. Go outside. Avoid indoor spaces with poor air flow as much as possible. Open windows and doors, use fans and portable air cleaners, run heating and air, and upgrade filters. (see CDPH guidance and fact sheet).
  • Choose outdoor spaces for social and fitness activities
  • Keep your distance. Use two arms lengths as your guide (about 6 feet) for social distancing with people outside your household when you are not sure that they are fully vaccinated.
  • Socialize with the same set of friends and relatives rather than mixing with many different people who are not vaccinated.
  • Be flexible. Be willing to change your plans or leave if you find yourself in a place where COVID-19 can spread more easily. For example, indoors in a loud crowded restaurant with a lot of people who are not wearing masks.
  • Wash your hands and/or use hand sanitizer often - especially after being in public spaces where surfaces are touched by many people. Avoid eating and touching your face with unwashed hands.
  • Stay home when sick. If you have symptoms of COVID-19, talk to a doctor and get a test. You should stay home and away from others until you get the result of your COVID-19 test or until your provider tells you that you don’t have COVID-19. To learn about symptoms and what to do if you are sick see ph.lacounty.gov/covidcare.
  • Delay travel until you are fully vaccinated. If you do travel and are not fully vaccinated, follow the CDC domestic and international travel guidance including staying home and quarantining upon return.


Vaccination is the best way to protect yourself and your loved ones from COVID-19. It will slow the spread of COVID-19 including variants of the virus. And it will also help lower the chances of new and more dangerous variants emerging.

  • If you are already vaccinated, encourage your family, friends, coworkers, and neighbors to get vaccinated. This includes recommended additional doses or booster doses. See COVID-19 Vaccine Eligibility: Primary, Additional & Booster Doses.
  • If you are not yet fully vaccinated, consider getting vaccinated now. Vaccines are safe, effective, and free to everyone regardless of immigration status. Talk with your doctor about any concerns.
Vaccines are widely available across LA without an appointment. Visit www.VaccinateLACounty.com to find a location near you. Call 1-833-540-0473 if you need help making an appointment, need transportation to a vaccination site, or are homebound. Phone lines are open from 8am to 8:30pm 7 days a week. Information is also available in many languages 24/7 by calling 2-1-1.


Your mask should fit snugly over your nose and mouth and be made of at least two layers so that they filter well. If you are in a setting where you are in sustained close contact with other people who may not be fully vaccinated, consider “double masking” (wearing a cloth face mask over surgical mask) or an N95 respirator. These offer a higher level of protection. This is especially important if you are not fully vaccinated and are indoors or in a crowded outdoor place.

Masks are now required in all indoor public settings, venues, gatherings, public and private businesses, and at outdoor Mega Events (events with over 10,000 attendees like concerts, sports games and parades) in Los Angeles County. Some exceptions apply - see the revised Health Officer Order and information below.

EVERYONE*, regardless of vaccination status, must wear a mask:

  • In all indoor public settings, venues, gatherings, and public and private businesses in Los Angeles County
  • On planes, trains, buses, ferries, taxis and ride-shares, and all other forms of public transport
  • In transportation hubs like airports, bus terminals, train stations, marinas, seaports or other ports, subway stations, or any other area that provides transportation
  • In healthcare settings (including long-term care facilities)
  • In state and local correctional facilities and detention centers
  • In Shelters and cooling centers
  • Indoors at any youth-serving facility (such as K-12 schools, childcare, day camps, etc.)
  • At outdoor Mega Events (events with over 10,000 attendees like concerts, sports games and parades)
  • In any other outdoor location where it is the policy of the business or venue


  • It is strongly recommended that you wear a mask at private indoor social gatherings with people outside your household, unless everyone at the gathering is fully vaccinated.
  • It is strongly recommended that you wear a mask at crowded outdoor events (that are smaller than Mega Events). In particular, wear a mask while in line to enter, exit, use the bathroom, or buy food or drinks.
  • It is strongly recommended that children wear a mask on playgrounds and in other outdoor spaces where they gather if distancing is not possible or practical.
  • If you are not fully vaccinated, it is strongly recommended that you wear a mask in crowded outdoor settings.
  • If you are in a setting where you are in sustained close contact with other people who may not be fully vaccinated, consider wearing a higher level of protection, such as wearing two masks (double masking) or an N95 respirator. This is especially important if you are not fully vaccinated and are in an indoor or crowded outdoor setting.

Note: You are allowed to take off your mask while you are:

  • Actively eating or drinking as long as you are sitting or standing in a specific place such as a table, counter, or ticketed seat. This means that you can briefly remove your mask when you are actually eating or drinking, but you must put it back on immediately afterwards. You must also wear a mask when you are waiting to be served, between courses or drinks, and while seated after finishing your food or drink.
  • Alone in a separate room or space.
  • Showering or swimming.
  • Receiving personal hygiene or personal care services (like a facial or shave) that cannot be done without removing your mask.

*There are some people who should not wear a mask, such as children younger than 2, people with certain medical conditions or disabilities, and people instructed by their medical provider not to wear a mask. Children ages 2 to 8 should wear a mask only when under adult supervision. See Who should not wear a mask and Special considerations for persons with communication difficulties or certain disabilities.

*In the workplace, workers must follow the most protective mask requirements as stated by Cal/OSHA and the County Health Officer Order. Certain employees may be exempt from wearing a mask in specific situations provided alternative safety measures are in place. See the Health Officer Order and Best Practices for Businesses webpage for details of workplace requirements.

Learn more about masks at ph.lacounty.gov/masks.

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  • Public Health has made reasonable efforts to provide accurate translation. However, no computerized translation is perfect and is not intended to replace traditional translation methods. If questions arise concerning the accuracy of the information, please refer to the English edition of the website, which is the official version.

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