Carnival Cruise Line sent the latest coronavirus-related protocols to customers booked to sail on the company’s new Mardi Gras ship in July and August.

According to Cruise Radio , Carnival President Christine Duffy sent an email to impacted passengers outlining the updated “Have Fun, Be Safe” protocols that will be in place when Mardi Gras makes her debut this summer.

Carnival’s health and safety regulations are based on the U.S. Centers for Disease Control and Prevention’s (CDC) guidelines and requirements, which include requiring COVID-19 vaccinations for all passengers at least 14 days before their cruise date.

In addition, vaccinated guests will not be required to wear masks on Mardi Gras , but they must continue using them inside cruise terminals. Inoculated guests will also be able to explore independently in ports of call or take Carnival-arranged excursions, but local restrictions need to be followed, such as health screening, testing, mask wearing and physical distancing.

Carnival also announced there would be “a small number of unvaccinated guests” on the ship, including “children too young to receive a vaccine and adults who are medically unable to be vaccinated.”

Passengers who have not received a full vaccination will face additional restrictions, including mandatory mask policies, increased social distancing measures and testing before and after voyages.

Customers can request a full refund before June 21 if they don’t wish to follow the updated Carnival protocols.