The next time you board a ship, you may want to salute your captain instead of shaking his hand.

At least one luxury cruise line has made no handshaking -- between crew and passengers -- official policy. Crystal Cruises has a no-shake rule for the captain, in addition to other "preventative measures" when it comes to health and safety on board its ships.



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"The safety and health of our guests and crew is paramount at Crystal Cruises. We maintain exemplary sanitation standards and facilitate preventive measures in accordance with Centers for Disease Control recommendations, including thorough disinfection of public areas, and high-touch surfaces like railings, door handles and elevator buttons," the cruise line said in a statement to ABC News.

"Other measures involve encouraging guests to use the complimentary anti-bacterial wipes before boarding the ship. And while the captain is very pleased to meet all our guests, he refrains from shaking hands as an additional preventive measure."

It's a policy that appears to work. Crystal Cruises last norovirus outbreak was in 2013, according to the CDC.

“In an abundance of caution, cruise lines take numerous steps to help promote the health and well-being of passengers onboard. This particular practice isn’t too common, but it is something we’ve experienced before on Crystal and a few other cruises. Ultimately, it’s a decision made by the executive team,” said Carolyn Spencer Brown, editor in chief of CruiseCritic.com.

Carnival Cruise Line, for example, will instruct officers to cease handshaking during special events if the medical team advises there are an elevated number of guests with gastrointestinal illness symptoms. An example of an event would be a Captains Party, where there's normally a lot of handshaking.

"This action follows recommendations from U.S. Public Health which administers the cruise industry's vessel sanitation program," Vance Gulliksen, a cruise line spokesman, told ABC News.

Both Crystal and Carnival said their policies have been in place for some time.

Royal Caribbean Cruise Lines told ABC News that while there was no policy pertaining to handshakes, it "follows strict guidelines and regulations that govern shipboard public health."