According to Dynata data released in July of 2020, Nationally, about 59% of Americans report using masks always, 27% use masks sometimes, and 14% use masks never.  This data set reports that mask usage was generally been increasing through the month of July.  Mask usage varied by partisanship by about 20 points, with Democrats more likely than Republicans to report using a mask.  This difference was still visible even when controlling for zip code and age.  In this data set, party preference was the strongest predictive factor of mask usage.

American Mask Usage and Partisanship

In an observational study of 15 states between April and May of 2020, state community-wide (as opposed to work-specific) mask requirements have prevented 200,000 Covid-19 deaths as compared with states who did not introduce such requirements.  This study does control for economic opening, but not mask regulation compliance.  Although other studies attempting to measure the effect of contamination on an individual with and without a face mask have been for the most part inconclusive and frustrated by small sizes in studies of a variety of respiratory illnesses. However, this study suggests that, en masse, mask usage is a useful preventative tool.

Effectualness of State-Level, Community-Wide Mask Legislation

Although the United States Centers for Disease Control and Prevention (CDC) initially warned against face mask usage by non-medical personnel, its April 2020 guidelines recommended mask usage in social settings, particularly when social distancing is difficult or when indoors. There are no national mandates for non-medical face masks in the United States; instead, legislation and enforcement have been delegated to state, county, and local governments.

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Face Mask Policies by Country 

- A face covering must be worn in most indoor settings. Individuals are expected to wear a face covering before entering the premises and must keep it on until they leave, unless there is a reasonable excuse for removing it.  
- Premises where face coverings are required are encouraged to take reasonable steps to promote compliance with the law. 
- The police can take measures if members of the public do not comply without a valid exemption. 
- The police and Transport for London offers have enforcement powers including issuing fines of £100 (halving to £50 if paid within 14 days).

England Face Covering Policies

In Singapore, it is compulsory to wear a face mask outside the home. Face masks must be worn:
- On public transport, in taxis, and in private hire cars.
- When walking to or at markets.
- At all workplace premises for essential workers.

Masks can only be removed when engaging in strenuous outdoor exercise, such as running and jogging. Non-compliance is penalized; first-time offenders can be fined up to S\$300, and repeat offenders can face higher fines or prosecution in court.

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