This document specifies the photometric and performance tests for headlamps used on railway vehicles. Unlike automotive headlamp standards (like ECE R112 for cars), railway headlamps operate under unique conditions: longer stopping distances, high vibration environments, dust, extreme weather, and the need for specific beam patterns that illuminate the track without blinding oncoming train drivers.

ISO 5948 is an international standard developed by the International Organization for Standardization (ISO). It specifies the requirements for the ultrasonic testing of solid wheels and tyres used on railway rolling stock.

It is vital to note that ISO standards are . While many websites may claim to offer a free "ISO 5948 PDF download," these are often unauthorized repositories that may be hosting outdated or altered versions. Using an unauthorized copy in a professional safety context can lead to legal liability and, more importantly, safety risks if the document is not the latest revision.