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Updated guidance on face coverings in Stanford facilities in Palo Alto and in other parts of main campus

Categories: Health & safety, Workplace & HR

Last modified on

Face covering use is one of the most important public health tools to prevent the spread of COVID-19. Well-fitting face coverings protect you and others when a potentially infectious person is talking, coughing, or sneezing, including if they are asymptomatic. Please refer to this page for detailed explanation of face coverings use requirements when on the Stanford campus.

***Regardless of vaccination status, personnel must continue to wear face coverings per these requirements during our recovery from the pandemic***

Quick links:
Face Covering Use Requirements
Types of Face Coverings
Special Provisions for N95 Respirator Use

Face covering use requirements

Stanford requires all faculty, staff, students, contractors, and visitors to wear face coverings in the following areas:

  • In common indoor areas, including in lobbies, common areas, hallways, restrooms, elevators, stairways, laboratories, shared offices, breakrooms,
  • Driving or riding in shared vehicles, and
  • Outdoors when minimum 6-foot physical distancing is not able to be maintained.

The following are scenarios where it is permitted not to wear a face covering:

  • When you are alone in a personal office (a single room), as long as the public does not regularly visit the room and the door is closed.
  • When actively eating or drinking (must put back on immediately after).
  • When exercising outdoors (e.g., walking, hiking, biking, running), provided persons are not passing within 6 feet of others. You should bring a mask with you, however, in case there is a possibility of not being able to maintain distance from others.

Additional information on face covering use for residential communities and dining areas can be viewed on the following web pages:

Instances of when it is not appropriate to wear a face covering include:

  • For health reasons:
    • Anyone who has been advised by a medical professional not to wear a face covering; students in this situation should follow up with the Office of Accessible Education (OAE) to receive an accommodation, and employees should contact their HR manager; or
    • Anyone who has trouble breathing, is incapacitated, or otherwise unable to remove a face covering without assistance;
  • For any worker to the extent wearing a face covering creates a safety hazard at work under established health and safety guidelines;
  • For children 2 years old or younger.

Types of face coverings

Face coverings used at Stanford must meet the following minimum CDC/ WHO criteria:

  • Fit snugly against the sides of your face and does not have gaps around the nose and chin.
  • Completely cover the nose and mouth.
  • Acceptable types include cloth masks with tightly woven fabric (i.e., cotton) with minimum two layers, disposable/surgical face masks, and masks with inner filter pockets.

Do not choose masks that have any of the following characteristics:

  • Fit loosely on your face with large gaps around the nose and chin.
  • Are made of fabric that is hard to breathe through.
  • Have exhalation valves or vents that allow viral particles to escape.
  • Are intended for the healthcare workers (i.e., N95 filtering facepiece respirators).

You can also consider commercially available disposable masks (e.g., KN95, FFP2, KF95).

Special provisions for N95 respirator use

As N95 respirators are designated as personal respiratory protection, workplace provision of N95s must adhere to SU’s Respiratory Protection Program.

During pandemic recovery

Departments are to provide N95 respirators to employees based on risks associated with assigned work. Currently, N95 respirators continue to be reserved specifically for medical care and other high-risk activities (Risk Level 4 on COVID risk matrix), and are not recommended for general comfort needs.

During wildfire smoke events

  • When the local AirNow Air Quality Index (AQI) consistently remains greater than 151, 
    • N95 respirators shall be made available for voluntary use for staff assigned work outdoors or in campus buildings with unfiltered air for more than 1 hour per work shift as per Cal/OSHA.
    • For non critical operations, re-assign staff to work in filtered air location or inform staff not to report for on-site work. 
  • When the local AirNow Air Quality Index (AQI) consistently remains greater than 500, N95 respirators use is required for the critical operations that must continue to resume, as required by Cal/OSHA. 

For support with KN95 or N95 respirator procurement, departments can reach out to EOC Logistics (

For information regarding obtaining face coverings for all Stanford sites, see the following information:

Can I wear my own face covering?

 Yes, you are allowed to wear a personally owned cloth face covering. Minimum requirements for face coverings are addressed below.

Is Stanford providing face coverings?

We encourage you to provide your own face covering wherever possible, and many members of our community have already purchased or made them for their use outside of Stanford. The university has a limited supply of face coverings available. Department managers can request reusable and disposable face coverings via and Environmental Health & Safety will work with each department on their specific needs.

For a limited time, there will be face coverings available for students who have not yet been able to obtain their own. Students may check at their residential dining halls or front desks, and can also seek further help from their Residence Dean or GLO Dean.

How do I choose the best face covering for me?

Face coverings used at Stanford must meet the following minimum CDC/ WHO criteria:

  • fits snugly against the sides of your face and does not have gaps
  • completely covers the nose and mouth
  • includes multiple layers of fabric (2 or more).

Do not choose masks that:

  • Are made of fabric that makes it hard to breathe (e.g., vinyl)
  • Have exhalation valves or vents that allow virus particles to escape
  • Are intended for the healthcare workers, including N95 respirators or surgical masks

What extra elements should I consider when choosing a face covering?

The most important consideration when selecting your face covering is the fit to face. While medical-grade masks and N95 respirators are conserved for the healthcare setting, consider the following elements when selecting a face covering:

  • Masks that fit properly (snugly around the nose and chin with no large gaps around the sides of the face)
  • Masks with a nose wire or fit closely over the nose to limit fogging for individuals that wear glasses
  • Masks with two or more layers of 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)
  • Masks with inner filter pockets

Alternatively, you can consider commercially available disposable masks (e.g., FFP2, KN95, KF94).

Are face coverings with exhalation valves or vents allowed on campus?

While the exhalation valve reduces air resistance when exhaling, they are not designed to contain respiratory droplets. Because of this, face coverings/masks with exhalation valves are not recommended for preventing the community spread of COVID-19 and are not appropriate face coverings on campus.

Should I double mask or knot the ear loops on my face covering?

Cloth and medical style disposable masks both work well in preventing airborne respiratory droplet spread, but having a close fit is important in making sure they work properly. The fit of the masks you currently wear can be improved by making sure that they are well-fitted to the curves of the face, preventing leakage of air around the mask’s edges especially around the nose and chin. 

CDC researchers have found two ways to improve the fit of these masks and reduce the spread of respiratory droplet particles by up to 95%:

1) Double masking by wearing a cloth mask over a disposable face mask

Note:  Individuals should avoid double masking combinations that result in uncomfortable breathing resistance, obstruct peripheral vision, or might otherwise impact long-term wearability.

2) Knotting or looping the ends of the ear loops of a disposable face mask where they attach to the mask’s edges and then tucking in and flattening the extra material close to the face (knotted and tucked masks, view instructional video here). 

Note:  This option is more suited for those with smaller faces.

Graphic showing the proper way to wear a face covering

For support in procurement of disposable face masks, departments can contact EOC Logistics ( Guidance on reuse of face coverings is available here.