Managing Hazardous Substances Exposure in a Specialist Workshop Environment

The Challenge

A specialist workshop facility carrying out mould-making, model-making and pottery activities required independent occupational hygiene support to assess employee exposure to a range of substances hazardous to health, including:

• Inhalable and respirable dust.
• Respirable crystalline silica (RCS).
• Volatile Organic Compounds (VOCs), including styrene.
• Refractory ceramic fibres.
• Isocyanates.

While general ventilation and PPE were in use, the organisation needed clear, defensible evidence to:

• Demonstrate compliance with COSHH Regulations and EH40 Workplace Exposure Limits (WELs).
• Understand exposure patterns across varied, task-based activities.
• Identify whether additional controls were required to maintain exposure ALARP.
• Provide reassurance to workers operating in a non-traditional manufacturing environment.

The Approach

Sysco Environmental carried out a structured COSHH air monitoring assessment in line with:

• COSHH Regulations 2002 (as amended).
• HSE guidance L5 and EH40.
• MDHS methodologies and BS EN 689:2018.
   

The assessment included:

• Personal exposure monitoring within operatives’ breathing zones.
• Static air monitoring to assess background concentrations and contaminant spread.
• Monitoring for dusts, fibres, VOCs, silica and isocyanates.
• Observation of work practices, ventilation arrangements and PPE use.
• Review of housekeeping, training and health surveillance arrangements.
• UKAS-accredited laboratory analysis.

Monitoring was undertaken during normal working activities to reflect realistic exposure conditions.

The Findings

The assessment identified that:

• All personal exposure results were below the relevant Workplace Exposure Limits.
• Inhalable and respirable dust levels were generally low to moderate, depending on task.
• VOC and styrene concentrations were well controlled under existing practices.
• Isocyanate exposures were below short-term limits but required ongoing precautionary control due to their sensitising nature.
• Respirable crystalline silica results were below the detection limit; however, due to the low WEL, these results were treated cautiously and managed as potentially significant.
• Static monitoring identified localised airborne concentrations, highlighting the need to prevent unnecessary spread.

While compliance was achieved, the findings reinforced that low results do not remove the duty to improve control, particularly for carcinogenic and sensitising substances.

The Recommendations

Sysco Environmental provided proportionate, forward-looking recommendations focused on maintaining control and preventing future risk, including:

• Installing purpose-designed Local Exhaust Ventilation (LEV) to capture contaminants at source.
• Avoiding dry sweeping, replacing it with HEPA-filtered vacuuming or wet cleaning methods.
• Improving RPE management, including face-fit testing, filter change protocols and suitability for task duration.
• Reinforcing training and instruction on hazardous substances and control measures.
• Introducing health surveillance questionnaires for workers exposed to sensitisers and carcinogens.
• Reviewing processes to identify opportunities for elimination or substitution of higher-risk materials

The Outcome

The assessment delivered:

• Clear, defensible evidence of COSHH compliance.
• Increased confidence that exposure risks were understood and proportionately controlled.
• Practical insight into where engineering controls would offer the greatest benefit.
• A structured basis for continuous improvement and future monitoring

Most importantly, it replaced assumptions with measured reassurance, ensuring worker health protection was demonstrable and robust.

Why This Matters

In environments where creative and manufacturing processes overlap, hazardous substances risks can be easily underestimated. This case study highlights the value of proactive occupational hygiene monitoring — not only to meet legal limits, but to ensure exposure is genuinely controlled, understood and responsibly managed.