As the Navy attempts to roll out guidelines to get surface fleet sailors better, more consistent sleep, the head of U.S. Fleet Forces Command said this week that being tired is often simply part of the job and needs to be further assessed.

“You’ve got to be able to handle fatigue,” Adm. Phil Davidson said Thursday in a speech at the Surface Navy Association’s annual symposium.

“This is about more than just, ‘the routine is too much.’”

Ship captains were ordered last year to submit plans for sailor work and watch rotations that would allow crews to sleep at more regularly scheduled intervals.

Davidson pointed to leaders aboard the destroyers Fitzgerald and John S. McCain who had to cope with fatigue after their ship collisions killed 17 sailors in the West Pacific last summer.

“Whether it’s lack of sleep or it’s the physical exertion of it all, there is a component of it there that is not robustly tested in the fleet,” he said. “We have to take a look at that.”

The Navy needs to find a way to “safely and proficiently” test sailors in higher-fatigue conditions, Davidson said.

“We have to teach them the difference between routine conditions and those fatigue conditions as well,” he said.

Dr. Nita Shattuck, a Naval Postgraduate School professor who has pushed for more restful ship shifts, said last year that a rested crew is better prepared for the fatigue and exhaustion of an emergency or combat situation.

Going without sleep for 22 hours leads to a degree of impairment equivalent to a legally drunk blood alcohol level of .08, according to a 2013 Surface Force message asking commanders for feedback on sleep reforms.

“You would not operate your car under those conditions,” the message said. “Neither should we ask our crews to operate shipboard systems or navigate in a similar mental or physical state.”