Face Covering Use and Care

Updated 11 August 2021


All faculty, staff, students, and visitors must wear a face covering that covers their nose and mouth whenever in buildings occupied by Princeton University. This includes, but is not limited to, all buildings and grounds, University vehicles, dining halls, Tiger Transit buses, conference rooms, office buildings, elevators, and parking structures. Individuals do not need to wear a face covering when alone in a room, cubicle, or vehicle or when outdoors. .

General Precautions

The CDC recommends the use of face coverings to decrease the spread of droplets containing the virus that may be generated when the wearer coughs, sneezes or talks.

Wearing a face covering does not replace the need for other measures to prevent the spread of the virus that causes COVID-19. In addition to wearing cloth face coverings, remember to:

  • Avoid contact with those who are sick, stay home if you're sick, and if you become sick at work, distance yourself from co-workers, contact your supervisor and go home.
  • Maintain at least 6 feet of distance (at least two arm lengths) from others on campus when possible. You are considered a close contact, regardless of the use of a face covering, if you were less than 6 feet away from a COVID-19 positive person for 15 minutes or longer, over a 24-hour period.
  • Frequently clean hands with soap and water or an alcohol-based hand sanitizer with at least 60% alcohol.
  • Avoid touching your eyes, nose, and mouth.
  • Practice good cough and sneeze etiquette.
  • Routinely disinfect high touch points, facilities, work areas, personal electronics, and shared equipment and spaces. Frequently-touched surfaces in University vehicles must be wiped down after each shift or before a different employee uses the vehicle, including steering wheels, door handles, turn signals and gear shifts, seat belts.

Choosing a Face Covering

The CDC currently recommends wearing face coverings that:

  • Have two or more layers of washable, breathable fabric (e.g. cotton) or tightly woven fabric (i.e., fabrics that do not let light pass through when held up to a light source).
  • Completely covers your nose and mouth.
  • Fits snugly against the sides of your face and doesn't have gaps around the sides of your face.

To improve how well your face covering protects you and others:

  • Choose a face covering with a nose wire to prevent air from leaking out of the top of the mask and bend It over your nose to fit it close to your face.
  • Use a mask fitter or brace over a disposable mask or a cloth face covering to prevent air from leaking around the edges of the mask.
  • Check for gaps by cupping your hands around the outside edges of the face covering to make sure no air is flowing from the area near your eyes or from the sides of it.
  • Add layers of material by using a cloth face covering that has multiple layers of fabric or wearing one disposable mask underneath a cloth face covering. The second face covering should push the edges of the inner mask against your face.

Other alternatives:

  • Non-medical, commercially available disposable masks can be worn as face coverings (e.g., FFP2, KN95, KF95, etc.). Please be aware that approximately 60% of KN95 masks in the US are counterfeit (fake) and DO NOT meet NIOSH requirements.
  • Neck gaiters can be worn if they have at least two layers or are folded to make two layers

They do not recommend wearing:

  • Face coverings that are made of fabric that makes it hard to breath, for example, vinyl.
  • Face coverings with exhalation valves or vents which allow virus particles to escape (the University's Face Coverings Policy also prohibits the use of them).
  • N-95 respirators or surgical masks as they are intended for healthcare workers
  • Two disposable masks because they are not designed to fit tightly. 
  • KN95 masks with any other type of mask or face covering.
  • Face shields in place of face coverings.

There Is emerging guidance that suggests the following face coverings are less protective:

  • Bandanas*
  • Scarves*
  • Loosely knitted ski masks and balaclavas

*The University's Face Coverings Policy prohibits the use of these.

With all of this guidance in mind, it is also important to make sure that you can easily breath and see when you are wearing your face covering(s).

Additional information regarding masks and face covering »

Putting on and Taking off your Face Covering

  • Always clean hands with soap and water or an alcohol-based hand sanitizer with at least 60% alcohol prior to putting it on, touching covering, or removing your face covering.
  • When removing face-covering use the ear loops, straps, or equivalent from behind the head to take off face covering.
  • Do not touch the front of the covering.

Additional information regarding how to wear masks and face covering »


Reusable Face Coverings

  • Note: Students and staff may not wear a reusable face covering when conducting research at the laboratory bench with hazardous chemicals, biohazards or radioactive materials. Disposable face coverings must be worn.
  • Use reusable coverings until they become damaged, soiled, or wet. Reusable face coverings should be taken home and laundered each night.
  • Reusable coverings should be machine-washed with warm or hot water and laundry detergent by the user. The coverings can be washed with other laundry items.

Disposable Face Coverings

  • Use disposable coverings until they become damaged, soiled, or wet.  If mask becomes damp from normal respiration, perspiration or from water, remove the mask and store in a sanitary location (e.g. paper bag to allow the mask to dry and then reuse.)  Disposable coverings can be used for up to 16 hours, unless they are damaged, soiled or soaked with moisture.   
  • Students and staff who conduct research at the laboratory bench with hazardous chemicals, biohazards or radioactive materials must discard the disposable face covering at the end of the day.
  • Employees should have a dry backup covering or mask stored in a sanitary condition (within a closed paper or plastic bag) in the event their mask becomes damaged, soiled, or wet. 

Employee and Student-Provided Coverings

The University is able to provide face coverings for employees and students. Requests can be made through the COVID-19 PPE & Supplies Order Form. Individuals can also wear face coverings that they have made or purchased, as long as coverings:

  • Fit snugly but comfortably against the side of the face
  • Completely covers your nose and mouth
  • Are secured with ties, ear loops, or equivalent
  • Include multiple layers of fabric
  • Allow for breathing without restriction
  • Do not have an exhalation valve. Such valves fail to protect persons around the wearer from virus spread.  


Departments can request face coverings for their employees through our COVID-19 PPE & Supplies Order Form. Cloth face coverings, where appropriate, are preferred over disposable face coverings for sustainability and supply chain purposes.

Undergraduate students who are living on campus will receive a package of cloth face coverings. If any undergraduate or graduate student should need an additional face covering, they can request one through the COVID-19 PPE & Supplies Order Form.

Other Types of Masks and Respiratory Protection

During this current pandemic, disposable and reusable face coverings that conform to CDC guidelines are what is recommended for the general population to wear to help slow the spread of the virus.  Though there are other types of masks and respiratory protection that can also offer protection, they are not appropriate for most members of the general public to wear, for various reasons that are discussed below.

Mask Type Description Image
Surgical Masks

Surgical masks are made from a material that traps or filters large particles and droplets. They do not seal to the face, so smaller particles and droplets can be inhaled. 

Wearing a surgical mask helps reduce the amount of particles and droplets released into the air, especially from coughs and sneezes. They provide limited protection to the person wearing the mask.

In healthcare and emergency response, surgical masks are worn by sick patients to reduce exposure to the healthcare workers and emergency responders. Surgical masks are in short supply and should not be used by the general public.

Surgical Mask

Surgical Mask

N95 Respirators

An N95 respirator is made from a material able to remove at least 95% of particles, mists, and droplets, including those that may carry viruses. When worn properly by individuals who have been medically approved, trained, and fitted for the mask, it provides protection from inhalation of such materials. Its effectiveness is dependent on its ability to form a seal on the face in order to prevent materials from entering through the sides of the mask. One size does not fit all, and there can be no facial hair that interferes with the seal of the mask.

N95 respirator are also in short supply and are only to be worn by individuals, including healthcare workers and emergency responders, who are in direct contact with ill patients. The shortage is so severe that many healthcare workers are reusing masks rather than disposing of them.

The Occupational Safety and Health Administration (OSHA) respiratory protection standard applies to employees wearing N95 masks. Per this standard, at least once each year an employee must complete training provided by Environmental Health and Safety (EHS), receive medical clearance by Occupational Health (OH), and have EHS or University Health Services (UHS) conduct a fit-test to ensure that the mask seals to the face properly.

N95 Respirator

N95 Respirator

Powered Air Purifying Respirator (PAPR) These can be loose or tight-fitting. The tight-fitting masks cover the entire face, including the eyes, nose, and mouth. The loose-fitting include a helmet and a hood that cover the entire head. They all have a motor that pushes contaminated air over a filter that cleans it, such that the user inhales filtered air. These can be used in healthcare as an alternative to an N95, and are effective against COVID-19. They require disinfection after each use.
PAPR Respirator


Half-facepiece respirators These are tight-fitting masks made of rubber or silicone with interchangeable cartridges that filter out different contaminants, based on the type of cartridge. Examples include particles like asbestos, chemical vapors, droplets and mists. HEPA (high efficiency particulate air) cartridges are effective for protection from COVID-19. However, these respirators are not comfortable for long-wear, need to be disinfected after each use, and require medical surveillance, fit-testing, and training.
Half-Face Respirator


Full-facepiece respirators These are tight-fitting masks that cover the eyes, nose and mouth. They work in the same way that a half-facepiece respirator functions, but are more protective since they cover more of the face. The same restrictions apply.
Full-Face Respirator


Self-Contained Breathing Apparatus (SCBA) These are tight-fitting full-face respirators that are attached to a tank of air or an air compressor. The air from the tank is pushed through the face of the mask to the user, providing the highest level of protection. These are impractical for protection against COVID-19.  

Note:  N95 respirators with valves, PAPR's, half and full-face respirators require the user to wear an additional face covering to block the exhalation valve.  Masks with valves allow the user to exhale potentially virus containing droplets and aerosols into the air and must be covered to control this.


  • Surgical masks and N95 respirators are in short supply and are needed to protect the nation’s healthcare workers and emergency responders. The CDC and NJ DOH currently do not advise the use of either by the general public.
  • Other types of respirators may provide protection from Covid-19, but require fit-testing, training, medical clearance, and frequent disinfection. Most are impractical for daily use and will require the user to wear an additional face covering to block emissions from the exhalation valve.
  • Cloth and disposable face coverings help to reduce the spread of Covid-19, especially during times when social distancing is challenging.

For More Information


Version 3.0 - August 2021

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