BATON ROUGE - A Louisiana medical facility says it's no longer allowing certain types of masks in its facilities after new science shows some masks are better than others.

Since the start of the virus, Americans have been encouraged to wear masks because they protect people from spreading the virus to others. A study by Duke University took a look at 14 different types of masks people have been wearing during the pandemic. The study found that the N95 mask is king, but other cotton cloth masks are about as effective as a standard surgical mask. Other popular masks, including neck gaiters and bandanas made of thin material, may be worse than not wearing a mask at all.

It's why Ochsner Medical Center is no longer allowing patients inside its buildings wearing bandanas, neck gaiters, and vented masks. Ochsner Medical Director of Hospital Quality and Infectious Disease Specialist Dr. Sandra Kemmerly says science has shown the neck gaiter might be worse than not wearing a mask.

"The theory is that the larger particles change in the bandana or the neck gaiter and made into smaller particles which stay in the air longer," Kemmerly said.

Ochsner Health says as it continues to learn more about COVID-19, its able to modify and improve its practices. With the new information published by Duke University, Ochsner has modified its mask guidelines to exclude neck gaiters, bandanas, and masks with valves. All staff, patients, and visitors are asked to wear an approved mask at all times. Those who come to the facility without an approved mask will be provided one prior to entering.

"We don't think they're safe for the patients in our building," Kemmerly said. "We're going to ask you to wear one that's perhaps more protective for others."

The Duke University study can be found here.