towing

the company i work for has now issued log books for the drivers to complete when towing anything other than a compressor or small tipping trailer with their single wheel transits ,due to the nature of the work ,callouts and long days are common , in the example they have sent out
the completed log book page has a number of days with duty time at 16 hours ,driving time 1.5 this would be fairly common for some gangs , someone has said that once you use the logbook and have been driving you can,t have that long a period of duty
can anyone help with the correct answer

cheers graham