Logs run like this:
1: You only need a log if travel over 100 AIR MILES (actually 115 statute miles) or work OVER a 12 hour day.
2: You can run two different "work weeks". 60 hours in 7 days or 70 hours in 8 days. IF you get a break in the middle of the week that is 32 or more hours, that resets the "work week". If you are in a position where you feel you will be keeping a log, you cannot swap what your "work week" is to make things happen. Choose one and stick with it.
3: Hours of Service (HOS) is this. You are allowed to work a 14 hour day, BUT, can only be behind the wheel for 11 of those hours. Once you hit 14, you are no longer allowed to drive, but you MAY continue to work as long as you want. BUT, here's the catch. You MUST have 10 hours continuous off before you can drive again. Lunches or breaks do not add to available time. Look at it this way, You have a 14 hour countdown timer when you start in the morning. NOTHING may stop or reset this timer except for 10 hours continuous off duty.
4: Just to throw a wrench into this supposedly "safety" oriented revenue generating set of rules, if you start and stop from the same point every day, once in between every 32 hour reset you can work up to 16 hours. BUT, you can still only be behind the wheel 11 hours total and still need 10 hours off before being able to drive.
Under 12 hours, under 100 miles, you do not need one. If, say once a month, you feel you are definitely within the required parameters, run a log for that day. IF you get stopped and they ask where the previous 7 days of log are, simply tell them "I never fit the requirements, but today I do" Let them do the footwork. Again, surrender nothing unless asked.
To me, being a contractor working locally, I'd not run a log. You have no timeclock, so it'd be pretty difficult for them to prove you had worked over 12 hours. They'd have to do one heck of a lot of investigation to catch you in a lie.
Now, here's a few tips. NEVER give more info in the log than what is required. NEVER do something such as "Wallahalla MI, fuel" in the remarks. This flag will have them asking for a fuel receipt. Write ONLY what the regulations ask for and nothing more. Always round the 15 minute "on duty, not driving" periods down if you can. They can even write tickets if your "Total miles traveled" and "On duty driving" math claim you are speeding.
Everything you need to know about logs can be found at the below links.
A word of advice, do your own homework with answering your log questions, many do not know what the rules are, as indicated by a few of the remarks I have read in this thread. Worst case scenario, Lack of a log is far cheaper than a tampered log if you get pushed into a corner.
In the first one, notice there is a different set of rules for "non-cdl" and "intrAstate" drivers. This may apply to you, but I am not sure. I only deal with interstate.
HOS Frequently Asked Questions (FAQ) - Federal Motor Carrier Safety Administration
Hours-of-Service Regulations - Federal Motor Carrier Safety Administration
Hours of service of drivers - Federal Motor Carrier Safety Administration
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