Please be cautious with operating non hands free in a vehicle. Although it may not fall into classification of mobile telephone it may well be deemed to be driving without due care and attention as would eating an apple whilst driving.
I have handheld personal radio and van set at work but we are not permitted to use the hand held device even if on a broach mic or harness. Your comment of not doing anything to interfere with your driving would be sound advice.
M0RCX - Leeds