No – If you are manning the booth. Yes – If you are performing convention services in the state of Nevada, NRS 618.9925 “convention service work includes, without limitation: constructing, installing, maintaining, operating, or removing trade show or exhibition displays; loading and unloading equipment and materials; erecting or dismantling booths and structures; rigging display areas; and installing temporary electrical power for use in display areas.” There is no minimum time requirement.