HSG258 Guidelines: What LEV Operators Need To Know
If you operate local exhaust ventilation (LEV) in your facility, HSG258 is a document you shouldn't ignore. Whether you manage a plastics processing line, a woodworking shop, or a chemical handling operation, understanding what HSG258 requires — and how it connects to your legal duties — is essential.
Find more air quality advice for the Industrial Sector here.
What Is HSG258?
HSG258, formally titled Controlling Airborne Contaminants at Work: A Guide to Local Exhaust Ventilation, is the Health and Safety Executive's definitive technical guidance on LEV systems. It covers the entire lifecycle of an LEV system: design, installation, commissioning, daily use, maintenance, and the formal examination and testing process.
It is guidance, not law — but in practice the distinction matters less than it sounds. COSHH Regulation 9 requires employers to maintain LEV and have it examined and tested at suitable intervals, and HSE inspectors use HSG258 as their benchmark for what adequate LEV management looks like. If your LEV programme doesn't follow HSG258, you will likely struggle to demonstrate COSHH compliance.
What is TExT in HSG 258?
The Thorough Examination and Test — known as TExT — is the formal inspection process set out in HSG258 and required by COSHH Regulation 9. For most LEV systems, this must be carried out at least every 14 months by a competent person.
TExT is not a simple visual check. It requires:
- Measurement of airflow performance against the original commissioning data
- Assessment of hood condition, ductwork integrity, and filter condition
- A written report confirming whether the system is performing adequately — or identifying where it has fallen short
Records must be kept for a minimum of five years and made available to HSE inspectors on request.
What HSG258 Expects From Operators
Beyond the 14-month TExT, HSG258 places ongoing responsibilities on the people who use and manage LEV day to day:
Daily and weekly checks. Operators should visually inspect hoods and confirm airflow indicators are reading correctly before use. Simple checks, but they form part of the documented maintenance regime HSG258 expects.
Commissioning data. Every LEV system should have a commissioning report that records baseline airflow performance. Without this, there is no reference point against which future TExT results can be measured. If your system doesn't have one, that gap needs to be addressed.
Competent person. HSG258 is clear that both the design and the TExT examination must be carried out by someone with the knowledge and experience to do so correctly. For TExT, the relevant qualification is BOHS P601 (or equivalent).
Where Sector-Specific Guidance Applies
HSG258 sets the standard that applies across all industries. For specific sectors, additional guidance layers on top of it. In plastics manufacturing, for example, PPIS13 identifies the particular fumes produced by moulding, extrusion and similar processes and references HSG258 as the standard those control measures must meet. The substances themselves, and their maximum permitted concentrations, are set out in EH40.
Understanding where your sector-specific obligations sit within that hierarchy — COSHH as the law, HSG258 as the method, and sector guidance as the application — is the foundation of a defensible LEV compliance programme.
Getting Your LEV Programme in Order
If you are unsure whether your current LEV testing and maintenance regime meets HSG258 expectations, the starting point is usually a review of your commissioning data and TExT records. From there, any gaps become clear.
ARM Environments carries out LEV testing, TExT examinations, and industrial fume tests across a wide range of industrial sectors. If you'd like to discuss your current programme or arrange an examination, get in touch with the team.
