The U.S. Dept. of Justice (DOJ), on behalf of the Federal Motor Carrier Safety Administration (FMCSA) has filed a response to two lawsuits against the hours of service (HOS) rule filed by Public Citizen and the Owner Operator Independent Driver Assn. (OOIDA) to the U.S. Court of Appeals for the District of Columbia Circuit.

In the responses, FMCSA defended HOS from Public Citizen’s two core complaints which challenge the agency’s extension of allowable driving time from ten hours to eleven hours per day and the 34-hr. consecutive off-duty time to restart the weekly accumulation of hours.

FMCSA pointed to a study that concluded that drivers were averaging 6.28 hours of sleep per day under the 2003 rule, an increase of more than an hour compared to the previous one. The agency implied that under the less-flexible sleeper berth provision of the current (2005) rule, “sleeper berth drivers” would get more sleep than under the 2003 rule.

“And even for sleeper berth drivers, FMCSA changed the rule to require eight consecutive hours in the sleeper berth—precisely to ensure that these drivers would have the opportunity for seven to eight hours of sleep,” stated DOJ.

FMCSA argued that “the [economic] costs of imposing a ten-hour [driving] limit far outweigh the safety benefits” mainly because several operational and laboratory studies found “little or no statistically significant difference” in driver performance between the 10th and 11th hours of driving.

FMCSA said that the 34-hour recovery provision is reasonable because drivers appear to use this off-duty time for operational flexibility rather than to maximize driving hours.

“Despite fears that drivers would use the restart to maximize their weekly hours, FMCSA’s field survey found that 95% of the recovery periods exceeded 34 hours in duration, with 50% longer than 58 hours,” DOJ said.

Public Citizen had complained that under both the 2003 and 2005 rule, drivers could potentially accumulate as much as 77 hours in a seven-day period and 88 in an eight-day period.

“If the recovery provision increases crash risk by allowing drivers to build up cumulative fatigue, as [Public Citizen] contends, one would expect the crash statistics to reflect that,” DOJ said. “But the statistics from 2004 tell a different story. Not only do carriers report lower crash rates, but the [Fatality Analysis Reporting System] data indicate a reduction in fatigue-related crashes.”

FMCSA also defended against OOIDA’s assertion that the agency’s amendment to the 2003 HOS sleeper berth provision from splitting ten hours of daily off-duty time into two periods with each period no less than two hours to having one period being at least eight hours is arbitrary and capricious.

OOIDA had contended that drivers prefer to have the option of shorter driving periods and more frequent rests that the more-flexible sleeper berth provision that was in effect before the 2005 rule allowed.

“Splitting sleep into shorter periods, even if the periods add up to seven to eight hours, is not sufficient,” DOJ stated. “In one study, for instance, researchers concluded that splitting sleep into two periods in a sleeper berth, without eight consecutive hours, increased the risk of fatality over twofold.”

The less-flexible sleeper berth provision in the 2005 rule remains controversial among drivers, with some complaining that they are forced to drive tired.

The American Trucking Assns., which intervened in the Public Citizen-led lawsuit in support of FMCSA, sponsored a study being conducted by Circadian Technologies, a business consulting firm specializing in sleep patterns, to find a way the current rule could be improved. The study documents impractical work/sleep patterns drivers engage in to comply with the current rules, particularly the sleeper berth provision.

See Sleep experts weigh in on HOS

DOJ noted that the Court vacated the 2003 rule because FMCSA failed to fulfill its statutory obligation to consider drivers’ health. DOJ said FMCSA considered factors such as exposure to diesel exhaust, potential harm from driving noise and exposure to vibration in truck cabs to conclude that the number of hours permitted by HOS would not have a negative impact on driver health.

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