Hours of Service Exemption: Adverse Driving Conditions

Hwy_11_Ontario_WinterWe all know winter weather can make driving hazardous, but for truck drivers it can also affect Hours of Service regulations (HOS) set by the Federal Motor Carrier Safety Administration (FMCSA). Extreme weather and adverse road conditions can require extra road time, make parking difficult, etc., all of which can result in a driver exceeding the standard driving limit.

In response, the FMCSA created an “Adverse Driving Conditions” exemption, which states:

“If unexpected adverse driving conditions slow you down, you may drive up to 2 extra hours to complete what could have been driven in normal conditions. This means you could drive for up to 13 hours, which is 2 hours more than allowed under normal conditions. Adverse driving conditions mean things that you did not know about when you started your run, like snow, fog, or a shut-down of traffic due to a crash. Adverse driving conditions do not include situations that you should have known about, such as congested traffic during typical “rush hour” periods.

Even though you may drive 2 extra hours under this exception, you must not drive after the 14th consecutive hour after coming on duty, and you must comply with the minimum 30-minute rest break provisions.”

If you do use this exemption, be sure and record in your log, along with a notation describing the circumstances. Also include the FMCSA ruling number for reference: 395.1(b)(1).

To learn more, check out this booklet from the FMCSA:


Interstate Truck Driver’s Guide to Hours of Service



New Hours of Service Rules for Interstate Truck Drivers

image of driver using truck drivers log bookJuly 1st is quickly approaching, and with it comes new Hours of Service rules. On that date, the Federal Motor Carriers Safety Administration (FMCSA) will begin to enforce the remaining HOS regulations (selected regulations went into effect on February 27, 2012) for truck drivers.

The new guidelines apply only to commercial motor vehicles in interstate commerce activity. Drivers and trucking companies that drive within just one state are not required to comply, as the state rule will apply.

According to the FMSCA, the changes that will go into effect on July 1st for property-carrying CMV drivers:

Driving limit: 11 hours

Drivers may drive a maximum of 11 hours after 10 consecutive hours off.

14 hour limit

Drivers may not drive beyond the 14th consecutive hour after coming on duty, following 10 consecutive hours off duty.

Rest breaks

A driver may drive only if eight hours or less have passed since the end of his/hers last off-duty or sleeper berth period of at least 30 minutes.

60/70 hour on duty limit

Drivers may not drive after 60/70 hours on duty in 7/8 consecutive days. A driver can restart a 7/8 consecutive day period after taking 34 or more consecutive hours off duty. This must include two periods from 1am to 5am home terminal time, and can be used just once a week (168 hours), measured from the beginning of the previous restart.

Sleeper berth provisions

Drivers that use the sleeper berth provision are required to take at least eight consecutive hours in the sleeper berth, plus a separate two consecutive hours in either the sleeper berth, off duty, or a combination of the two.


For the full outline of the new Hours of Services rules and regulations, see the FMCSA publication, Interstate Truck Driver’s Guide to Hours of Service.

image of truck driver safety handbookWhen FMCSA regulations change, it’s important to have the most up-to-date information and supplies on-hand. Be sure to pick up our spiral-bound Federal Motor Carrier Safety Regulations (FMCSR) handbook and see our selection of driver log books.