**The Purpose of Black Tubes on Roads**

The black tubes stretched across roads are **pneumatic traffic counters**, vital tools in traffic management. These simple devices collect essential data on vehicle counts, speed, and road usage, helping transportation authorities plan safer, more efficient infrastructure.

**How They Work**
When a vehicle passes over the tube, it generates a burst of air that triggers an electrical signal in a connected counter. Single-tube setups count vehicles, while dual-tube configurations measure speed, direction, and vehicle classification.

**Why They Matter**
The data guides key decisions such as setting speed limits, placing signs, and planning repairs. Temporary installations capture snapshots of traffic patterns, while permanent ones provide long-term monitoring to track trends.

**Shaping Policies and Responding to Concerns**
These counters inform traffic policies, helping address issues like speeding or congestion. Agencies rely on the data to implement measures like speed bumps or signal adjustments, ensuring roads meet current and future demands.

Black tubes may seem minor, but they are crucial to keeping our roads safe and efficient.