The following vehicles are not permitted to use the CLEM7:
- Vehicles and loads exceeding 4.6m high
- Vehicles carrying commercial quantities of dangerous goods and specifically any vehicle displaying a dangerous goods placard
Detection systems outside the tunnel will notify drivers of height limits. Warning signals will be initialised if the height limit is breached. All vehicles exceeding the height limit will be advised to take an alternate route.
If drivers of overheight vehicles proceed then entry will be physically prevented by an overheight barrier structure designed to protect tunnel infrastructure.