**Motorways and dual carriageways** are safer than **conventional roads** in terms of fatal accidents. This is due to several factors:

- **Fewer accidents:** Motorways and dual carriageways record fewer accidents compared to other roads. This is specifically mentioned in the context of fatal accidents, which are more frequent on roads outside towns or cities, but not so much on motorways and dual carriageways.

- **Road design:** Motorways and dual carriageways are designed to facilitate smoother and safer traffic, with separate lanes for each direction and no level intersections, which reduces the possibility of head-on collisions and other types of serious accidents.

- **Driving conditions:** On motorways and dual carriageways, driving conditions are usually more controlled, with higher speed limits but also fewer interruptions and crossings, which contributes to safer driving.

For these reasons, motorways and dual carriageways are considered safer than conventional roads in terms of fatal accidents.