FAQs for COVID-19 Health and Safety

Updated July 28, 2022


What cleaning protocols are in place for offices, classrooms, and other campus spaces?

Building Services custodians, on a daily basis, clean and disinfect classrooms, lobbies, atriums and high-contact public surfaces such as light switches, handrails, elevator buttons and doorknobs.

How often are bathrooms cleaned?

Building Services custodians clean all bathrooms across campus at least once per day.

What do Building Services custodians clean and what is my department or I expected to clean?

Building Services custodians clean and disinfect restrooms and high-contact surfaces in public spaces. Individuals should clean and disinfect frequently touched items in their own work area on a daily basis, including computer and peripherals, doorknobs and handles, light switches, phones, desks, tools and other shared equipment.

In the case of shared departmental spaces such as break rooms, users must take responsibility for wiping down surfaces and equipment, including tabletops, refrigerator and microwave door handles, coffee makers, and photo copier touch panels.

Where do I get cleaning supplies?

If you need disinfectant wipes or other cleaning supplies for your work area, request a supply from your supervisor. Supervisors may contact ehs@princeton.edu if assistance is needed to obtain supplies.

What products are effective for disinfection of the COVID-19 virus?

A number of chemical products are anticipated to be effective at inactivating the COVID-19 virus, based upon previous testing of the disinfectant against similar viruses.  The Environmental Protection Agency (EPA) maintains the criteria used to assess the effectiveness of disinfectants and maintains a list of products and conditions of use (such as contact time) that are anticipated to be effective against the COVID-19 virus.  These products are found under the EPA List N: https://www.epa.gov/pesticide-registration/list-n-disinfectants-use-against-sars-cov-2-covid-19

Due to interest in this subject, the EPA has recently launched an interactive version of List N to make it easier to search. https://cfpub.epa.gov/giwiz/disinfectants/index.cfm

A number of manufacturers are actively testing their products the verify their product’s effectiveness by directly testing against the COVID-19 virus.  More information will be provided once additional information is available on disinfectants verified against COVID-19.

Is it okay to use disinfectant wipes intended for surfaces  to clean my hands?

Unless clearly indicated in the instructions provided by the manufacturer, most cleaning products (including disinfecting wipes) designed for use on hard surfaces should not be used to sanitize your hands.  These products are often formulated with harsher chemicals than similar sanitizing wipe products intended for use on a person and may result in harm, such skin injury or irritation and serious injury to the eye if remaining residue is accidentally wiped into the eyes.



Do I have to wear a face covering when on campus? 

Starting March 14, 2022, face coverings will be optional in most University spaces, with some exceptions. 

  • Where required by state or local agencies, currently in the McCosh Health Center
  • As instructed by Global and Community Health following a recent positive test for COVID-19 or when identified as a close contact
  • When faculty or staff conveners of a class, lab, gathering, or meeting require participants to wear a mask
  • When certain categories of visitors do not wish to attest to being up to date on current vaccination

Continue to carry a mask with you at all times in the event you are in one of the above situations.

Additional information is available in the March 2 Covid Newsletter and memo to the University community.

May I choose to wear a face covering, even where it is not required?

Yes, please feel free to wear a face covering if that is your preference. The University encourages a culture of non-judgment and no assumptions regarding mask-wearing.

My prescription glasses fog up when I wear a face covering. What can I do?

If your glasses are fogging up when you wear a face covering, it is likely that there is too much of a gap around the nose. Here are a few ways to manage this:

  • Wear a face covering that has an adjustable wire at the bridge of the nose. Ensure that the material fits snugly around the nose.
  • Rest your glasses over your face covering to help block the air from escaping, thus preventing fogging. 
  • Use an anti-fogging eye glass/safety glass cleaning wipe.  In addition to helping to remove smudges on your glasses, these wipes deposit a thin film that helps to prevent fogging.  If you do not have anti-fogging wipes, try baby shampoo*, glycerine soap*, dishwashing detergent*, or a small amount of toothpaste* on a soft cloth to clean your glasses. Shake off the excess and let them air dry. This technique leaves a thin film that reduces surface tension that builds up from your breath, causing fogging.

* If one of the alternatives to anti-fogging wipes are used, avoid the use of fragranced materials and materials claiming superlative cleaning properties (grease cutting, whitening, etc) as these may contain additives that can be irritating or harmful to your eyes and skin. 

I need to wear safety glasses and they fog up when I wear a face covering. What can I do?

By forming a tight seal across the nose and under your eyes, Safety goggles are far less likely to fog up than safety glasses. Consider wearing goggles instead. Alternatively, follow the guidance above for prescription glasses. 

Is a disposable mask safer than a cloth face covering?

Not necessarily. When it comes to masks, fit is the most important factor. The CDC recommends selecting a mask that completely covers your nose and mouth and fits snugly against the sides of your face. Cloth masks should have two or more layers of washable, breathable fabric and should be laundered regularly. Disposable medical masks fitted around your nose may also be used. KN95 or KF94 masks are readily available commercially and may be used, but are not required.

We do not recommend that departments provide N95 respirators for voluntary use for several reasons. The Occupational Safety and Health Administration has very specific requirements, such as fit-testing and medical clearance, for when employers require employees to wear N95s, and our experience has shown that achieving proper fit for an N95 can be difficult and may not achieve the desired level of protection.

How and how often should I clean my face cloth face covering?

Wash your face covering after each day or when it becomes soiled. 

  • Use a washing machine and regular detergent, warm or hot water. You can wash face coverings with your other laundry. Air dry or place in the dryer. Some elastic can be damaged over time in the dryer, so check the elastic after drying.
  • Wash by hand with dish detergent or castile soap and warm or hot water. Air dry.

Do face coverings really work in reducing the spread of disease?

There are numerous peer-reviewed studies that confirm that masks, even cloth masks, are effective in reducing the spread of COVID-19.

Tight-fitting face coverings, whether reusable cloth masks or disposable, protect others from potentially infectious droplets that might be generated by the person wearing the mask, and protect the person wearing the mask. This is particularly important because people can spread the virus that causes COVID-19 without showing any symptoms.

The following CDC resources provide guidance and scientific background:

This article provides links to several peer-reviewed studies: Do face masks work? Here are 49 scientific studies that explain why they do



Is there a review and approval process for indoor or outdoor gatherings of any size?

No. As of July 4, 2021, neither indoor or outdoor meetings of any size require review and approval by the Gatherings Review Team.

What do I have to do if I want to host meeting attended only by University faculty, staff, and/or students?

See the Guidance on Gatherings, Events, and Conferences. Organizers are responsible for ensuring that all attendees follow public health guidance. Schedule the space using the EMS system. Keep a record of attendance for at least two weeks.

May University-hosted events be open to the public?

Religious services, varsity and recreational athletic events, arts performances, and lectures are permitted to be open to the general public. See the Guidance on Gatherings, Events, and Conferences for more information. 

May I host a conference that includes attendees that are not members of the Princeton University community (faculty, staff, students)?

University-hosted conferences and meetings may include visitors. Pre-registration is required. See the Guidance on Gatherings, Events, and Conferences for more information. 

Do I need to approve each visitor attending a conference or public event?

No. The Visitor Policy considers individuals attending a University-hosted conference or public event to be pre-approved.

Are masks or social distancing required for indoor events?

In non-instructional spaces, the campus community is asked to be considerate and respond to the requests of individuals who prefer mask-wearing, including those who may be at higher risk.

Do I need to take attendance at the meetings or events? If so, how long do I need to maintain the list?

It is recommended that you maintain a list of attendees for at least two weeks after the event to be able to assist in contact tracing if someone at the event is diagnosed with COVID-19. This is especially helpful if the event involves visitors from outside the campus community. A printable PDF for listing attendees is available on the EHS website. 

Is food allowed at gatherings? If so, is there a need for social distancing during meals? May I use an outside caterer?

Yes, food is allowed and social distancing is not required. You may use any outside vendor, but if there will be servers, please use Campus Dining catering services.  



What has the University done to improve building ventilation systems in light of the risk of exposure to COVID-19?

The University has taken a number of steps, including:. 

  • Servicing HVAC systems in buildings that have not been occupied to ensure that they are working properly and efficiently.
  • As possible, increasing the amount of outside air and decreasing the amount of recirculating air in buildings. 
  • Where possible, replacing air filters with highly efficient filters, such as MERV-13 filters.
  • Reducing or disabling occupancy controls that decrease ventilation rates when the space is unoccupied.

I'd like to have the ventilation in my building/office assessed. What should I do?

At this time, Facilities and EHS are not conducting additional ventilation assessments in campus buildings.

What can I do to improve ventilation in my building?

  • If your space has operable windows and opening them will not disrupt air conditioning or heating, open windows while occupying the space. Do not leave windows open and unlocked when the building is unoccupied. 
  • Leave on exhaust fans in restrooms if they are operated by a switch.

How much outside air is provided to our campus buildings?

*Wherever possible, the University meets or exceeds the outside air parameters recommended by ANSI/ASHRAE Standard 62.1-2019 on Indoor Air Quality.  

Ventilation systems in our older buildings may not provide the amount of outside air specified by this standard. However, all of our air handler units have been set to provide the maximum amount of outside air while maintaining reasonably comfortable temperature and relative humidity levels. 

Is air in my office recirculated from other parts of the building?  

With the exception of laboratories and machine shops, the ventilation system in most buildings on campus provide a mix of outdoor and recirculated air.  Even the most stringent indoor air quality standards for classrooms, offices and assembly areas allow for a mix of outside and recirculated air.

Recirculated air is filtered before it is delivered back to occupied spaces. The quality of a filter is based upon its ability to capture small particles. The MERV (Minimum Efficiency Reporting Values) rating is a measurement of a filter's ability to capture particles of a certain size and range from 1 to 16. The higher the MERV rating the better the filter is at trapping certain size particles. When possible, our ventilation systems are equipped with MERV-13 filters, as recommended by CDC. All air filters are periodically cleaned and replaced by trained Facilities staff to ensure proper function

Some of the air in my building is recirculated. If a co-worker is diagnosed with COVID-19, will I need to quarantine due to the recirculated air?

No. Decisions about the need to quarantine a staff member or student are made by UHS physicians and nurses and are based primarily upon your physical distance from the ill person. You may be told to quarantine only if you were within six feet of the ill person for more than 15 minutes over the course of 24 hours during a specific window. 
I work in a small office and I am concerned because there is no mechanical ventilation system.

Some older buildings are equipped with heating and cooling devices but do not receive fresh air via a mechanical ventilation system. If windows are available, open them unless opening the windows affects your seasonal allergies. If the unventilated space is used for assemblies of staff or students, EHS may make recommendations on how to safely use the space.

Should I purchase or bring in an air purifier for extra protection in the office?

Additional air purification is not necessary and can place undue demand on building electrical systems. If a department wishes to purchase portable air purifiers, please see the portable HEPA filter guidance found on the EHS website.

What about filtration units in classrooms?

For those few classrooms with no mechanical ventilation, portable filters have been placed by Facilities (if assigned by the Registrar) or may be purchased by departments (if managed at the department level). These units must comply with guidance outlined on the EHS website



The following FAQs refer to the Visitor Policy effective July 28, 2022. Click on questions for answers or scroll below index.

General Info


Info for Hosts

Defining 'Visitor'

What are the expectations for all visitors? 

Visitors must cancel their planned visit if they test positive for COVID-19 within ten (10) days of the planned start of their visit, if they are experiencing symptoms consistent with COVID-19, or if they were identified as a close contact of an individual who tested positive within the last ten (10) days and have not had a negative COVID-19 test since the exposure. Visitors must notify the sponsoring host if they test positive for COVID-19 within five days after their visit. 
Regardless of vaccination status, all visitors must comply with the requirements of face coverings in effect at the time of their visit to campus 
What are the categories of visitors? 

Broadly, the University divides visitors into two categories. 
    1.    The following categories of visitors must be fully vaccinated [1] for COVID-19 and must be prepared to show proof of vaccination. All of these visitors must be sponsored by a member of the University community (faculty, staff, graduate student, or undergraduate student) or a University department or unit. 

  • Visitors staying overnight in University dormitories. This does not include graduate student apartment complexes, such as Lakeside or Lawrence Apartments. 

  • Individuals participating in summer residential programs, such as sports camps, summer research, etc. 

  • Individuals participating in multi-day programs sponsored by the University, such as Princeton University Prep, summer day camps, Princeton Writing Program, Teachers as Scholars, Teacher Prep, regular tutoring, etc. Does not include conferences and events. 

  • TigerCard holders (e.g., faculty spouses, graduate student dependents, etc.) with access to the libraries or Dillon Gym facilities. 

  • Visiting Student Research Collaborators.  

  • Individuals participating in University-sponsored programs where removal of a mask indoors is necessary. 

  • Long-term visits of more than five days, consecutively or non-consecutively 

    2.    The following categories of visitors listed below must be prepared to show proof of being fully vaccinated [1] for COVID-19, and follow the policy for masks in effect at the time of their visit OR have a negative test for COVID-19 via PCR within 72 hours before the start of the scheduled visit or via rapid antigen test within 8 hours before the start of the scheduled visit and be prepared to show proof of the negative test OR 
agree to wear a mask at all times when indoors. These individuals cannot remove their masks inside of University buildings, including to eat or drink.  

  • Individuals invited or approved by faculty, staff, or students or by a department or unit for short-term visits (5 days or fewer, consecutively or non-consecutively, no overnight stay on campus) and who will not have independent access to buildings.  

  • Attendees at University-sponsored meetings, conferences, and events. 

  • Individuals invited to participate in sponsored human subjects research. 

  • Individuals participating in or attending events in University buildings where the sponsor is a third-party entity that has permission to use the facilities 

Are boosters required for visitors? 

As of July 28, 2022, visitors only need to have received a primary series of COVID-19 vaccine. 
What does it mean to “be prepared to show proof” of COVID-19 vaccination status? 

Proof of Vaccination may include an official CDC COVID-19 vaccination card, a vaccine certificate from an official source (e.g., public health agency, government agency, or authorized vaccine provider), a mobile phone app, or a digital or physical photo of a vaccination card or record. It is at the discretion of individual event organizers or University hosts if they wish to examine this proof. 
What does it mean to “be prepared to show proof” of a negative COVID-19 test? 

Acceptable tests are a PCR test conducted within 72 hours of the visit or a rapid antigen test completed within 8 hours of the visit. Proof of a negative test can include a photo of the negative test result (for home antigen tests), an email or other screenshot from a pharmacy or other provider, or a printout of the negative test result. It is at the discretion of individual event organizers or University hosts if they wish to examine this proof. 
What is the logic for this length of time to constitute an acceptable test? 

The CDC and NJ Department of Health both indicate that a PCR test within 72 hours is acceptable for travel and is within the limitations of timing to receive results from most PCR testing laboratories. For rapid antigen tests, the chances of a false negative diminish the closer in time to the visit that the test is conducted. 
Can individual departments or events be stricter than University guidance (i.e. continuing to require all visitors to be up-to-date on COVID vaccines?) 

Yes, individual departments or events can be stricter than University guidance and can require their visitors to show proof of vaccination status, show proof of a negative test, etc. However, these departments should not expect support from service departments at the University (i.e. University Services, DPS, etc.) in facilitating stricter compliance measures. 
Do I need approval from Environmental Health and Safety (EHS) for a visitor to enter a campus building? 

No, EHS approval is not required. Most visitors can be approved by the immediate supervisor of the faculty or staff member sponsoring the visit. 
Who is NOT a visitor? 

Visitors means any individual who does not have an appointment as University student, faculty, or staff, including those who are NOT a(n) 

  • Enrolled degree-seeking undergraduate and graduate student  

  • Current employee of the University, including:  

    • Faculty and staff who currently have access to campus buildings. 

    • Casual employees.  

    • Visiting researchers and visiting faculty with formal appointments. 

    • Long-term temporary staff agency personnel. 

  • University affiliates who regularly spend time on campus interacting with faculty, staff, and students are covered by the University Vaccination Policy.1 

Secondary occupants residing with graduate or undergraduate students in University dormitory housing, as approved by Housing and Real Estate Services, are not considered visitors to their residences and residential complex, but are considered visitors to other University buildings.

I am hosting an indoor event where food will be served and would like to allow individuals to attend who are not fully vaccinated. What are the options? 

Since eating and drinking requires removal of masks, individuals who are not fully vaccinated will need be prepared to show proof of a negative test. 
Who is considered a pre-approved visitor that does not need to go through the approval process? 

The following visitors do not require sponsors or approval. If not up-to-date with COVID-19 vaccination, they must wear a mask indoors around other people. 

  • Contractors and vendors retained to provide essential services on campus, including repair, technical assistance, renovation, construction, maintenance, moving, food delivery, waste removal, etc. and who comply with the Requirements for Vendors and Contractors. 

  • Guests in non-dormitory University residences. Visitors who are not up-to-date with COVID-19 vaccination must wear a mask in common spaces, such as lobbies, common rooms, hallways, etc. 

  • Regulatory inspectors, including federal, state, and local agency inspectors on campus for planned or unplanned visits

See the  Visitor Policy  for additional information about each of these groups. 
Are emeritus faculty considered visitors? 

If emeritus faculty currently have access to campus buildings, they are not considered visitors. 
Are caterers considered visitors? 

No. Caterers are subject to the Requirements for Contractors and Vendors  and may provide service on campus if they comply with applicable food safety/health and insurance requirements.  
My department works with volunteers. Are they considered visitors? 

Yes. Volunteers whom faculty or staff sponsor to be on campus are considered visitors.
Are alumni considered visitors? 

Yes. At this time, alumni are considered visitors. 
Are retirees considered visitors? 

Yes. At this time, retirees are considered visitors. 
May hiring managers invite prospective candidates on campus for interviews? 

Yes. The hiring manager will act as the sponsor for prospective candidates.



If your question is not listed on this document, please contact EHS at ehs@princeton.edu or 609-258-5294.


[1] Fully-vaccinated means that at least two weeks have passed since receiving the second dose of a two-dose vaccine or the single dose of a one-dose vaccine.


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