As coronavirus cases continue to climb across the country, more state officials have made the use of masks or face coverings mandatory in public.
Currently, 46 out of 50 states have some form of face mask guidelines in place, but some are more lenient than others.
The most strict mask requirements exist in a total of 17 states, where residents are required to wear a mask outside at all times when social distancing isn't possible, and also face penalties if they don't abide by the rules.
It differs from the more lenient states that, for example, only make people wear masks in certain businesses. Four states — Iowa, Montana, Wisconsin, South Dakota — have no mask requirements at all.
The official guidelines from the Centers for Disease Control and Prevention (CDC) suggest that everyone should be wearing face coverings in "public settings where other social distancing measures are difficult to maintain."
A recent study found that the use of face masks has been the most effective way to reduce person-to-person spread of the virus.
The US has seen one of its worst weeks since the start of the outbreak, recording more than 2.5 million cases and 125,539 deaths to date, according to a tracker by Johns Hopkins University.
Scroll down to see which 17 states have mandated the use of face coverings in public.
Gov. Gavin Newsom issues the order to make mask-wearing mandatory in most public places on June 19.
Under the new law, all Californians must wear some type of face coverings in public, including while shopping, taking public transport, or seeking medical care, according to the Los Angeles Times.
The same applies to public outdoor spaces where social distancing is not an option.
"Simply put, we are seeing too many people with faces uncovered — putting at risk the real progress we have made in fighting the disease," Newsom said in a statement.
"California's strategy to restart the economy and get people back to work will only be successful if people act safely and follow health recommendations."
There were no more details about how the order will be enforced or if violators will face any punishments, CNN reported.
Any Connecticut resident over the age of 2 must wear a face mask in a public space where social distancing isn't possible, according to an executive order signed by Gov. Ned Lamont that came into effect on April 10.
This also includes public transport.
The only people exempt from this order are those with a medical condition, NBC Connecticut reported.
However if anyone refuses to wear a face covering, they aren't required to provide proof that they're medically exempt.
Delawareans are required to wear face coverings in public places including in grocery stores, pharmacies, doctor's offices, and on any form of public transportation, according to a statement issued by Gov. John Carney on April 20.
Only children under the age of 12 are exempted from this rule, due to the risk of suffocation.
"Wearing a face covering in public settings is important to prevent transmission of this disease. But wearing a face-covering is not permission to go out in public more often," the statement said.
4. District of Columbia
While initially, there was some confusion around face masks rules in the district, DC Mayor Muriel Bowser ordered the use of face coverings when conducting essential business or travel and social distancing isn't possible.
Masks or other face coverings are required in grocery stores, pharmacies, and takeout restaurants. On public transportation, face coverings are required if individuals are unable to be six feet apart. Children between the ages of 2 and 9 are advised to wear masks.
A state emergency order issued by Gov. David Ige on April 20 requires customers as well as employees at essential businesses to wear face coverings, according to local media.
However, masks are not required in banks or at ATM's. Furthermore, those with pre-existing health conditions, first responders, and children under the age of five are exempt from this rule.
If anyone violates these rules, they could face a fine of up to $50,000 or up to a year in prison, according to the order.
Illinois Gov. JB Pritzker ordered the use of face masks for anyone stepping outside their house as of May 1, local media reported.
This includes everything from shopping at essential businesses, picking up food, or visiting the doctor. It is also implemented in any public space where people cannot maintain 6 feet of physical distance.
Even though Kentucky Gov. Andy Beshear signed an order requiring all state residents to wear a mask in public as of May 11, the governor also said that those who are caught not wearing one, won't be fined or arrested.
However, the order does give businesses the right to turn away anyone who does not wear a mask and if law enforcement officers see unmasked people, they will ask them to don a mask.
Not everyone in the state has been following the order.
"It's a concern," Judge-Executive Mason Barnes of Simpson County — which has one of the highest infection rates in the state — told USA Today. "I'd say 70% to 80% of the people are not wearing masks when they're out and about."
Maine residents are required to wear face-coverings anytime they step foot into a supermarket, retail store, pharmacy, or doctor's office, according to an order issued by Gov. Janet Mills which went into effect on May 1.
Anyone taking public transport is required to wear face coverings, according to Gov. Larry Hogan's order that came into effect on April 18.
Other places where this is mandatory include grocery stores, pharmacies, liquor stores, laundromats, and hardware stores, according to USA Today.
Employees of essential businesses and customers over the age of 9 must also wear them.
In Massachusetts, residents are not only required to wear face masks in public while indoors, but also need to wear them in outdoor spaces where social distancing isn't possible.
The order, issued by Gov. Charlie Baker, went into effect on May 6.
According to Michigan state law, "any individual able to medically tolerate a face covering must wear a covering over his or her nose and mouth."
This also applies to business owners, who must provide their workers with "gloves, goggles, face shields, and face masks as appropriate for the activity being performed."
Businesses are also allowed to deny entry to anyone who refuses to wear a mask.
Nevada was one of the most recent states to implement a mandatory mask order which went into effect on June 25.
Face coverings must be worn in public, but also in private businesses. Those who are exempted from the order include people with a medical condition that prevents them from wearing a mask, homeless people, and children between 2 and 9 years old, according to The Independent.
During his announcement last week, Nevada Gov. Steve Sisolak said: "Wearing mask coverings saves lives, period. End of story. We owe it to each other to accept the fact that wearing face mask coverings saves lives."
12. New Jersey
New Jersey was the very first state to make customers and workers wear face coverings at essential business sites.
Wearing a mask is also mandatory on public transit, and if anyone is seen without a mask, they could be denied entry, according to CNN.
13. New Mexico
Face masks are mandatory in New Mexico in all public settings, except while eating, drinking, exercising, or for medical reasons.
The mandate came into effect on May 15.
Gov. Michelle Lujan Grisham said during a news conference: "As the state opens up and our risk increases, the only way we save lives and keep the gating criteria where it is is if we're all wearing face coverings,"
"It's not a guarantee against the virus, but it really helps slow the spread, and that's why we're mandating it," Grisham added, according to Las Cruces Sun News.
14. New York
New York, which was one of the worst-affected states at the peak of the coronavirus pandemic, made it mandatory for everyone over the age of 2 to wear a face mask in public on April 17.
New York Gov. Andrew Cuomo has been very vocal about wearing face coverings while out, regularly reminding residents on Twitter.
Yesterday the US hit a record high for new COVID cases. WEAR A MASK.— Andrew Cuomo (@Andrew Cuomo)1593087988.0
Essential businesses must give their employees masks and are allowed to deny customers entry for those not wearing one, according to an order from Pennsylvania's Department of Health which went into effect on May 8.
The rule on mask-wearing also applies to people on public transport, according to Pennlive.
16. Rhode Island
Rhode Island residents are required to wear face masks in all public settings, whether these are indoors or outdoors.
Gov. Gina Raimondo told news reporters on May 5: "You don't leave your house without your car keys or your phone or your wallet, so don't leave your house without your face mask," NECN reported.
"We're trying to strike a balance between compliance... but we don't want to be overly heavy-handed," she added.
A few days later, the mayor of Providence, Rhode Island encouraged state residents to "socially shame" people not wearing masks, according to USA Today.