Source control (respiratory disease)
Source control is a strategy for reducing disease transmission by blocking respiratory secretions produced through speaking, coughing, or sneezing. 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. In addition, respiratory etiquette such as covering the mouth and nose with a tissue when coughing can be considered source control.
Contrast with personal protective equipment
While source control protects others from transmission arising from the wearer, personal protective equipment protects the wearer themselves. Cloth face masks can be used for source control but are not considered personal protective equipment as they have low filter efficiency, although they are easy to obtain and reusable after washing. There are no standards or regulation for self-made cloth face masks.Surgical masks are designed to protect against splashes and sprays, 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. Surgical masks are regulated by various national standards to have high bacterial filtration efficiency. 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.
| Type | Source control | Inhaled air filtration | Ref |
| Cloth face mask | |||
| Surgical mask or procedure mask | |||
| Respirator without exhaust valve | |||
| Respirator with exhaust valve |
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 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. Masking patients reduces the personal protective equipment recommended by CDC for health care personnel under crisis shortage conditions.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.