What should be assessed during an inspection of a speed indicator?

During an inspection of a speed indicator, assessing the ability to indicate speeds accurately is crucial. This is because the primary function of a speed indicator is to provide precise speed readings to help ensure safe operations. Accurate speed readings are essential to comply with speed restrictions and safety protocols. If the speed indicator does not accurately reflect the speed, it can lead to unsafe situations, including derailments or accidents due to excessive speeds.

While other aspects, such as lights being operational or the indicator functioning at various track speeds, may be important for overall safety and visibility, the core requirement is that the speed indicator accurately conveys the speed of the train. This accuracy directly impacts the decision-making process of the crew and overall operational safety.