Under GB 7258-2017 (Clause 8.4) and GB 23254, what is the mandatory requirement for reflective contour markings (车身反光标识) on dangerous goods transport trucks?

1. High-grade retroreflective marking tape (red and white alternating) must be continuously applied along the full length of the sides and around the rear outline of the vehicle body
2. Reflective markings are only required on the front windshield wipers
3. Only black non-reflective duct tape is permitted on chemical transport trucks
4. Reflective markings are optional if the driver turns on the interior cab dome light