What standards are used to assess LEV system performance?

The primary standard used to assess LEV system performance in the UK is HSG258, published by the Health and Safety Executive. This guidance outlines how systems should be examined and tested, and what constitutes adequate performance.

HSG258 focuses on whether the LEV system is doing its job, namely controlling exposure at source. It covers airflow measurements, hood capture effectiveness, and visual checks of the system’s condition. The emphasis isn’t just on numbers, but on practical control.

In some cases, design benchmarks or industry-specific guidance may also be referenced, particularly where unusual processes are involved. However, HSG258 remains the core document inspectors and duty holders rely on.

Using the correct standard ensures consistency and makes test results defensible during audits or inspections.