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High-quality, well-fitting face masks are effective at reducing the risk of transmission of respiratory infections (including COVID-19) and are an important component of a comprehensive strategy to reduce the risk of illness, hospitalization, and death from COVID-19 and other respiratory infections. Masks can provide both source control and personal protection within healthcare settings.
This document is intended to provide information that California healthcare settings should consider when developing and implementing their own facility-specific plans about face masking for source control, based on their patient population, facility considerations, and respiratory virus transmission metrics. The Centers for Disease Control and Prevention (CDC) provides additional recommendations for facilities on when to implement broader use of source control masking. Local health jurisdictions and other entities may implement requirements that go beyond this statewide guidance based on local circumstances.
In the workplace, employers are subject to the Cal/OSHA COVID-19 Non-Emergency Regulations or in some workplaces the Cal/OSHA Aerosol Transmissible Diseases (ATD) Standard (PDF) and should consult those regulations for additional applicable requirements.
This source control masking guidance is intended to be implemented in addition to other respiratory infection prevention measures, including immunizations for COVID-19 and other respiratory diseases, which remain the most effective strategy in preventing infection, disease, and serious illness and death from COVID-19.
Source control masking involves the use of well-fitting facemasks or respirators to cover a person's mouth and nose to prevent spread of respiratory secretions when they are breathing, talking, sneezing, or coughing. The use of masks by healthcare personnel (HCP) for source control of respiratory infections in healthcare settings serves two purposes:
Local circumstances that healthcare facilities may consider when developing plans regarding source control masking for HCP include (but are not limited to):
Multiple reports describe decreases in healthcare-associated respiratory infections temporally associated with source control masking . Some infection control experts promote HCP masking as part of Standard Precautions for all patient encounters .
To promote patient/resident safety and prevent healthcare-associated transmission of respiratory infections, healthcare facilities may consider implementing source control mas king requirements for HCP during certain activities or times.
These may include requirements that HCP wear masks:
The California Department of Public Health (CDPH) continues to recommend that healthcare facilities require HCP who have had an exposure to someone with COVID-19 infection and are working during their post-exposure testing period to wear an N95 respirator for source control at all times while in the facility until they have a negative test result on or after day 5.
In addition, all HCP who have a suspected or confirmed respiratory infection should stay home and not care for patients when ill. HCP who must remain at work with a suspected or confirmed respiratory infection may be required to mask for source control.
In jurisdictions or facilities where source control masking is required of all HCP in patient/resident care areas or interactions, additional requirements for un/under-vaccinated HCP could apply throughout the facility, including non-patient/resident care areas.
Healthcare facilities may consider implementing source control masking policies for visitors based on the same local circumstances as for HCP as listed above, such as community transmission of respiratory viruses, emergent variants, and the number of ill staff.
In situations where surgical masks are required for source control, voluntary use of a respirator provides increased source control and protection for the wearer. This does not supersede any requirements for use of a respirator under Cal/OSHA COVID-19 Non-Emergency Regulations or the ATD Standard (PDF).
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Originally published on July 28, 2023