"When the NTSB investigates we try to make recommendations so that horrible crashes don't happen again, and so we're going to tell agencies, 'you have to address sleep apnea,'" Rosekind said.
The Department of Transportation declined our request for an interview, but in a statement said, "Safety is the top priority at the Department of Transportation and we recognize that sleep apnea can have a direct effect on those responsible for transporting goods and people. DOT is committed to ensuring that all train operators, truck drivers and pilots are fit for the job and receive the treatment they need to combat sleep apnea."
While critics say nationwide rules for sleep apnea testing are needed immediately, others are not convinced sleep apnea is the sole cause of accidents.
Todd Spencer, the executive vice president of the Owner-Operator Independent Drivers Association (OOIDA), said the theory that sleep apnea causes accidents is "junk science."
"We've not see the impact in safety and health [of sleep apnea] that [the NTSB] talks about," Spencer said. "Generally when somebody's saying, 'This is--we're killing people, we're killing people,' they have an economic interest in pursuing this… either they're make money from treatment, they make money from diagnosis, they make money maybe through lawsuits."
But the DOT said one of its agencies, the Federal Motor Carrier Safety Administration, has begun research that could one day lead to sleep apnea regulation under a law President Obama signed last year.
However, Spencer worries about the cost of getting each driver or conductor tested.
"Just the cost of doing that test is over $2,600," he said. "That's a pretty big piece of change, and that's just for doing the test."
And medical testing is not the only solution. There is also a new low-speed, autonomous breaking device, already widely available in high-end cars, that has the technology to brake to avoid a collision and alert drivers as they start to nod off.
Spencer of the OOIDA is skeptical and believes "technology will never stop crashes," but the NTSB says these high-tech solutions, some of which are just beginning to be available as optional extras on trucks in the United States, hold promise.
"We specifically have looked at some things in rail and trucking and have made recommendations to find innovative technologies that could make a difference in alerting a driver to their fatigued state," Rosekind said.
Dr. Michael Caldwell of the ABC News Medical Unit contributed to this report