I work in a shop and only drive occasionally. Do I have to comply with the 60/70 hour rule?

Yes, you do have to comply with the 60/70 hour rule. On the days you are in the shop, you should have a time record that the company keeps on file for six months, and you should start a log page for the days that you are required to log driving. 

If your company does not keep time records, you must have a record on your on-duty time for the last seven days at the carrier and start a log sheet for the day you are driving.