Source control (respiratory disease)
![](http://upload.wikimedia.org/wikipedia/commons/thumb/c/c4/Coronavirus_COVID-19_face_mask_in_supermarket.jpg/220px-Coronavirus_COVID-19_face_mask_in_supermarket.jpg)
Source control is a strategy for reducing disease transmission by blocking respiratory secretions produced through speaking, coughing, or sneezing.[1] Surgical masks are commonly used for this purpose, with cloth face masks recommended for use by the public only in epidemic situations when there are shortages of surgical masks.[2][3] In addition, respiratory etiquette such as covering the mouth and nose with a tissue when coughing can be considered source control.[4]
Contrast with personal protective equipment
While source control protects others from transmission arising from the wearer, personal protective equipment protects the wearer themselves.[5] Cloth face masks can be used for source control but are not considered personal protective equipment[1][5] as they have low filter efficiency (generally varying between 2–60%), although they are easy to obtain and reusable after washing.[2][6] There are no standards or regulation for self-made cloth face masks.[4]
Surgical masks are designed to protect against splashes and sprays,[3] but do not provide complete respiratory protection from germs and other contaminants because of the loose fit between the surface of the face mask and the face.[7] Surgical masks are regulated by various national standards to have high bacterial filtration efficiency (BFE).[8][9][10] N95 masks and other filtering facepiece respirators can provide source control in addition to respiratory protection, but respirators with an exhaust valve might not provide source control.[3]
Type | Source control | Inhaled air filtration | Ref |
---|---|---|---|
Cloth face mask | ![]() |
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[1][2][5] |
Surgical mask or procedure mask | ![]() |
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[3][7] |
Respirator without exhaust valve | ![]() |
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[3] |
Respirator with exhaust valve | ![]() |
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[3] |
COVID-19 pandemic
During the COVID-19 pandemic, cloth face masks for source control have been recommended by the U.S. Centers for Disease Control and Prevention (CDC) for members of the public who leave their homes, and health care facilities are commended to consider requiring face masks for all people who enter the facility. Health care personnel and patients with COVID-19 symptoms are recommended to use surgical masks if available, as they are more protective.[11] Masking patients reduces the personal protective equipment recommended by CDC for health care personnel under crisis shortage conditions.[12]
The World Health Organization and European Centre for Disease Prevention and Control recommend face masks in non-healthcare community settings in severe epidemic situations with a high prevalence of asymptomatic but infectious persons, especially when visiting crowded indoor spaces such as grocery stores, public transportation, and for certain workers who must come into physical proximity with many other people.[4]
References
- ^ a b c "FAQs on the Emergency Use Authorization for Face Masks (Non-Surgical)". U.S. Food and Drug Administration. 2020-04-26. Retrieved 2020-05-21.
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: CS1 maint: url-status (link) - ^ a b c "Using face masks in the community - Reducing COVID-19 transmission from potentially asymptomatic or pre-symptomatic people through the use of face masks". European Centre for Disease Prevention and Control. 2020-04-08. Retrieved 2020-05-21.
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: CS1 maint: url-status (link) - ^ a b c d e f "Interim Infection Prevention and Control Recommendations for Patients with Suspected or Confirmed Coronavirus Disease 2019 (COVID-19) in Healthcare Settings". U.S. Centers for Disease Control and Prevention. 2020-05-18. Retrieved 2020-05-21.
{{cite web}}
: CS1 maint: url-status (link) - ^ a b c "Using face masks in the community - Reducing COVID-19 transmission from potentially asymptomatic or pre-symptomatic people through the use of face masks". European Centre for Disease Prevention and Control. 2020-04-08. Retrieved 2020-05-21.
{{cite web}}
: CS1 maint: url-status (link) - ^ a b c "Meat and Poultry Processing Workers and Employers: Interim Guidance from CDC and the Occupational Safety and Health Administration (OSHA)". Centers for Disease Control and Prevention. 2020-05-12. At section "Cloth face coverings in meat and poultry processing facilities". Retrieved 2020-05-24.
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: CS1 maint: url-status (link) - ^ Rengasamy S, Eimer B, Shaffer RE (2010). "Simple Respiratory Protection—Evaluation of the Filtration Performance of Cloth Masks and Common Fabric Materials Against 20–1000 nm Size Particles". Annals of Occupational Hygiene. 54 (7). Oxford University Press: 789–798. doi:10.1093/annhyg/meq044. ISSN 0003-4878.
The results showed that cloth masks and other fabric materials tested in the study had 40–90% instantaneous penetration levels against polydisperse NaCl aerosols employed in the National Institute for Occupational Safety and Health particulate respirator test protocol at 5.5 cm s−1.
- ^ a b "N95 Respirators and Surgical Masks (Face Masks)". U.S. Food and Drug Administration. 2020-04-05. Retrieved 2020-05-23.
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: CS1 maint: url-status (link) - ^ Robertson, Paddy (15 March 2020). "Comparison of Mask Standards, Ratings, and Filtration Effectiveness". Smart Air Filters.
- ^ 中华人民共和国医药行业标准:YY 0469–2011 医用外科口罩 (Surgical mask) (in Chinese)
- ^ 中华人民共和国医药行业标准:YY/T 0969–2013 一次性使用医用口罩 (Single-use medical face mask) (in Chinese)
- ^ "Interim Infection Prevention and Control Recommendations for Patients with Suspected or Confirmed Coronavirus Disease 2019 (COVID-19) in Healthcare Settings". U.S. Centers for Disease Control and Prevention. 2020-05-18. Retrieved 2020-05-21.
{{cite web}}
: CS1 maint: url-status (link) - ^ "Strategies for Optimizing the Supply of N95 Respirators". U.S. Centers for Disease Control and Prevention. 2020-04-02. At section "Prioritize the use of N95 respirators and facemasks by activity type". Retrieved 2020-05-21.
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: CS1 maint: url-status (link)