Smoking below deck on US navy submarines will be banned by the end of the year so that non-smokers do not have to inhale secondhand smoke, the US navy announced on Thursday.
"Recent tests have shown that, despite our atmosphere purification technology, there are unacceptable levels of secondhand smoke in the atmosphere of a submerged submarine," said the head of US submarine forces, Vice Admiral John Donnelly.
The ban enters into effect "no later" than December 31, Donnelly said in a statement.
"The only way to eliminate risk to our non-smoking sailors is to stop smoking aboard our submarines," he said.
The order follows a 2006 US surgeon general's report that states there is no risk free level of exposure to secondhand smoke, and a year-long health study conducted in 2009 aboard nine different submarines that showed "measurable" levels of secondhand smoke.
Until now permission to smoke aboard any of the 57 subs in the US fleet was at the discretion of each submarine captain.
According to Mark Jones, spokesman for the US navy submarine fleet, 40 percent of the submarine sailors are smokers.