COSHH Air Monitoring

COSHH Air Monitoring UK for Workplace Exposure Assessment, WEL Compliance and Risk Reduction

COSHH air monitoring measures airborne contaminants in the workplace so you can assess exposure risk, verify controls, and demonstrate compliance with Workplace Exposure Limits (WELs) where applicable. If your activities generate dusts, fumes, vapours or aerosols, exposure monitoring provides objective evidence to support risk assessments, protect worker health, and reduce enforcement and liability risk. Monitoring is especially important where processes change, controls are upgraded, complaints occur, or health surveillance flags potential issues.

When COSHH Air Monitoring Is Required

COSHH air monitoring is typically required where:

• There is potential exposure to airborne hazardous substances (dust, silica, welding fume, solvents, isocyanates, acids, fumes)
• You need to assess compliance against Workplace Exposure Limits (WELs)
• Local exhaust ventilation (LEV) or RPE is relied upon and you need evidence controls are effective
• Processes, materials or production volumes change and exposures may increase
• Risk assessments are outdated or based on assumptions rather than measured data
• Health surveillance, worker feedback or incidents indicate potential exposure concerns

Purpose of COSHH Air Monitoring

The purpose is to quantify exposure so controls can be targeted and proportionate. Monitoring helps you answer: what is in the air, who is exposed, for how long, how exposures compare to limits, and what control improvements will reduce risk most effectively.

How COSHH Air Monitoring Works in Practice

A robust exposure assessment considers tasks, duration, variability, workforce roles and control measures. Monitoring may include personal exposure sampling (preferred for WEL comparison) and targeted static/background sampling where relevant. Results are interpreted alongside work practices, LEV performance, housekeeping, RPE use and maintenance records so actions are practical and evidence-led.

What COSHH Monitoring Can Cover

Monitoring scope is tailored to your substances and processes. Where breathing air is supplied for RPE, see Breathing Air Quality Testing.

• Inhalable and respirable dust (including task-based exposure assessment)
• Respirable crystalline silica (RCS) where relevant to cutting, grinding, demolition or materials handling
• Welding fume and metal fume exposure assessment
• Solvent vapours and VOCs (cleaning, coating, printing, manufacturing)
• Acid mists and process aerosols where applicable

What the Service Delivers

• A monitoring strategy aligned to your COSHH objectives and exposure scenarios
• Sampling results presented clearly with exposure interpretation against relevant criteria
• Identification of high-exposure tasks and priority control opportunities
• Practical recommendations (LEV improvements, work practice changes, RPE governance, housekeeping)
• A report suitable for COSHH assessments, audits, contractor assurance and internal governance

Standards, Guidance and Regulatory Context

COSHH monitoring and exposure assessment commonly align to HSE COSHH (Control of Substances Hazardous to Health), HSE EH40 Workplace Exposure Limits (WELs), and HSE HSG258 Local Exhaust Ventilation (LEV) guidance.

Who COSHH Air Monitoring Is For

• Manufacturing and industrial sites with airborne dusts, fumes or vapours
• Construction and demolition teams managing dust and silica exposure risk
• Operators using solvents, coatings or chemicals with inhalation hazards
• Facilities strengthening audit readiness and compliance evidence systems