In an unusual Saturday evening vote, Congress passed a $1.1 trillion spending bill that the White House has indicated President Barack Obama will sign.

The bill is about more than spending. It includes regulations affecting everything from banking to the environment. It also includes an amendment to the hours-of-service rules for commercial drivers that was introduced over the summer by Maine Senator Susan Collins.

The amendment suspends for one year the requirement that drivers include two back-to-back 1 a.m. to 5 a.m. periods in any 34-hour “restart” period. That requirement is itself relatively new. It took effect in July 2013 along with the requirement that drivers take a 30-minute rest break within the first 8 hours.

The amendment also suspends a once-in-seven-days limit on the use of the restart, which was introduced in 2004 to allow drivers to begin a new 70-hour work week more quickly. Previously, truckers were required to be off-duty 48 hours between work weeks.

The regulations sought to reduce night-time driving, but they had an unintended consequence. They lead to more commercial vehicles on the road early in the morning, when commuters and school buses are out. Morning commute hours are considered by some studies to be less safe than night-time hours.

The Collins amendment maintains the 34-hour rest mandate but removes the requirement that it include two overnights, and it allows drivers to take more than one restart in a seven-day period, thereby starting a new 70-hour workweek.

The regulations that are affected are contained in 49 C.F.R. § 395.3:

. . .

(c)(1) Through June 30, 2013, any period of 7 consecutive days may end with the beginning of an off-duty period of 34 or more consecutive hours. After June 30, 2013, any period of 7 consecutive days may end with the beginning of an off-duty period of 34 or more consecutive hours that includes two periods from 1 a.m. to 5 a.m.

. . .

(d) A driver may not take an off-duty period allowed by paragraph (c) of this section to restart the calculation of 60 hours in 7 consecutive days or 70 hours in 8 consecutive days—or, in the case of drivers in Alaska, 70 hours in 7 consecutive days or 80 hours in 8 consecutive days—until 168 or more consecutive hours have passed since the beginning of the last such off-duty period. When a driver takes more than one off-duty period of 34 or more consecutive hours within a period of 168 consecutive hours, he or she must indicate in the Remarks section of the record of duty status which such off-duty period is being used to restart the calculation of 60 hours in 7 consecutive days or 70 hours in 8 consecutive days—or, in the case of drivers in Alaska, 70 hours in 7 consecutive days or 80 hours in 8 consecutive day

The spending bill passed Congress with a bipartisan 56-40 vote, sending the bill to President Obama, who is expected to sign it into law on or before Wednesday, December 17, 2014.