Robert,
This will initially sound very complicated, hard to explain and understand, and unnecessarily complex but the rules were created and are manipulated by a government bureaucracy following congressional guidelines. They are intended to protect the trucking industry and the public from 80,000 pound or greater monsters hurtling down the highways at high speeds 24 hours/day 365 days/year in sunny and dry or rain, sleet, snow, or icy conditions, piloted by sometimes tired or angry drivers fighting the system to earn their living. The rules are enforced very strongly, even harshly, for eighteen wheel truckers. My state and probably most states offer free publications explaining the rules. You can buy logbooks at any truck stop and the rules are simply stated in each logbook.
DOT rules allow being on-duty either 70 hours out of every 8 day period or 60 hours in a 7 day period. Following that you must reset your logbook with 34 hours off duty which means out of the truck unless the truck has a sleeper compartment. A law enforcement officer can demand to see a motel receipt proving it unless you can convince him you stayed at a friend's house in a strange city. The 34 hour figure sounds arbitrary but is simply one night or 10 hours of rest plus an additional 24 hour day off for rest and recuperation. I have learned through experience that the rules actually work pretty well. My mind and body know if I stretch the rules.
A commercial driver can drive 11 hours/day and be on duty 4 hours/day for a total of 14 hours driving/on-duty following a 10 hour rest period.
On-duty time includes everything but actual driving or resting. It specifically includes pre-trip or post trip daily vehicle inspection (required), loading, unloading, repairs, breakdowns, DOT inspections, state port of entry inspections, waiting to load/unload, completing logbooks, records, and other administrative duties, etc.
The second driver can drive during your four hours on-duty but not driving which can allow the truck to travel for a total of 14 hours after the 10 hour rest period. This is a little difficult to explain and understand but basically, unless the truck has a sleeper compartment, the second driver cannot legally extend the driving period very much because you must be out of the truck resting after 14 hours. If the truck has a sleeper compartment another set of complex rules apply. The rules are established this way because DOT knows that you can't actually "rest" while another driver drives in a truck without a sleeper
If your equipment looks clean and well maintained and you the driver look reasonably well-groomed and rested, if you drive within the speed limits and obey all traffic rules and general road courtesy, if you don't come to the attention of a police officer, and if you don't have the misfortune to get caught up in someone else's bad luck or stupid driving, you may never be asked to produce a logbook. But, and this is a big but, the penalties for not keeping a log book and following DOT regulations can be very severe. Any young hotshot trooper or scale operator looking to change the world who happens to observe that you stop the truck and immediately exit without taking a minute to pull out your logbook and make an entry can demand to see the logbook. Ask any CDL over-the-road driver. Several TDR members who frequent these forums are professional drivers and maybe one will comment here.
I hope this helps. If I overlooked or misstated any of this I'm sure someone will correct me or clarify my explanation. When you first become aware of DOT regulations they sound overwhelming and near impossible to comply with but as your familiarity and understanding grow they become more reasonable and easier to accept and follow.
Harvey
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