Client Overview
A UK-based food manufacturer producing a wide range of freshly prepared, high-quality food products. Operations include pastries, breads, and powdered ingredients supplied to leading food retailers.
The Challenge
On-site production includes tray cleaning and sieving operations, both of which generate airborne flour dust. Effective control of this dust is critical to protect operatives’ health and to maintain food safety standards.
To comply with the Control of Substances Hazardous to Health (COSHH) Regulations 2002, Regulation 9, the site’s Local Exhaust Ventilation (LEV) systems required a Thorough Examination and Test (TExT).
Two LEV systems were in use:
- Tray cleaning dust control system
- Sieving dust extraction system for powdered food ingredients, including flour and sugar
Neither system had been examined for a prolonged period. Both were designed to recirculate filtered air back into the workplace, increasing the importance of effective filtration, system integrity, and ongoing performance monitoring.
An initial appraisal identified that neither system could be fully assessed for compliance due to a combination of:
- Mechanical defects
- Degraded filter media
- Ductwork design limitations
Flour dust is a known respiratory sensitiser and can cause occupational asthma. It has a Workplace Exposure Limit (WEL) of:
- 10 mg/m³ (8-hour TWA)
- 30 mg/m³ (15-minute STEL)
However, as flour dust is an asthmagen, exposure should be reduced as far below the WEL as reasonably practicable. HSE guidance indicates that, with good control practice, levels below 2 mg/m³ (8-hour TWA) are typically achievable, and health surveillance is usually required.
Our Solution
We carried out an Initial Thorough Examination and Test (TExT) on both LEV systems in accordance with:
- COSHH Regulation 9
- HSG 258 – Controlling Airborne Contaminants at Work
Tray Cleaning Dust Control System
The system comprised a Donaldson Torit DCE reverse-jet filter with an integral 15 kW fan, serving two extraction points.
At the time of inspection, the associated machines and extraction hoods had not yet been installed, meaning full performance testing was not possible. The examination identified several critical issues requiring attention before the system could be safely returned to service, including:
- Failed filter media
- A damaged explosion relief membrane
- No differential pressure monitoring across the filters
Sieving Dust Extraction System
This system also utilised a Donaldson Torit DCE reverse-jet filter, serving two sieve tipping hoods used during the handling of powdered ingredients.
The inspection identified:
- Failed and contaminated filter media
- Incorrect fan rotation significantly reducing airflow
- Ductwork configuration contributing to low conveying velocities
Explosion protection measures were also reviewed to confirm suitability and compliance with DSEAR requirements.
For both systems, we provided detailed test data, observations, and clear remedial recommendations to help the client restore safe, effective, and compliant LEV operation.
The Result
The Thorough Examination and Test gave the client a clear and comprehensive understanding of the condition and performance of their LEV systems, identifying critical defects that required rectification before compliance could be achieved.
Once the recommended remedial works are completed, both systems can be:
- Fully assessed and benchmarked
- Maintained in line with COSHH, HSG 258, and DSEAR guidance
The assessment also established a robust baseline for future inspections, helping the client improve dust control, reduce exposure risks, and maintain a safe working environment.
Is your LEV system due for a Thorough Examination and Test? Contact us today for a free, no-obligation quote.