India, Oct. 22 -- An Instagram video has triggered alarm over the reliability of SOS buttons installed in commercial cabs, after a commuter demonstrated that the emergency-alert mechanism failed to function despite being mandatory under government safety norms.

The video, shared by Instagram content creator Tiger Koul, shows him sitting inside a cab and attempting to press the SOS button installed near the passenger seat. Instead of triggering an alert, the indicator light switches off, suggesting a malfunction. Koul points out that while such systems are projected as a key safety feature, especially for women travelling alone, several of them may not be operational in reality.

Koul then questions the cab driver about the cost of the de...