Isocyanate Testing: What Employers Need to Know as HSE Inspections Increase

In recent months, we’ve seen a sharp rise in enquiries from businesses that use paints and coatings containing isocyanates – particularly bodyshops, vehicle repair businesses and other spray‑based operations.

This increase is not accidental. The Health and Safety Executive (HSE) has launched a programme of targeted inspections focusing on workplaces where isocyanate exposure is a known risk, especially within the motor vehicle repair sector.

If your business uses two‑pack (2K) paints or similar products, it’s worth understanding what isocyanate testing involves, why the HSE is focusing on it, and what practical steps you can take now.

What are isocyanates – and why is the HSE concerned?

Isocyanates are a group of chemicals commonly found in:

• Two‑pack (2K) paints and lacquers

• Coatings and finishes

• Foams, adhesives and sealants

They are one of the leading causes of occupational asthma in the UK, particularly among vehicle spray painters.

A key issue is that:

• Isocyanates can be invisible and odourless

• Exposure can occur through inhalation or skin contact

• Once a worker becomes sensitised, even very small future exposures can trigger severe reactions

Because of this, the HSE expects employers to do more than rely on PPE alone and to actively verify that their control measures are working.

Why is isocyanate testing important?

Under the Control of Substances Hazardous to Health (COSHH) Regulations, employers must:

• Assess the risks from isocyanate exposure

• Put appropriate control measures in place

• Monitor exposure where necessary

• Provide health surveillance for workers at risk

For workplaces using isocyanate‑based paints, this commonly includes biological monitoring, usually via urine testing.

Biological monitoring:

• Confirms whether existing controls (spray booths, ventilation, RPE) are actually effective

• Acts as an early warning before health problems develop

• Is recommended by the HSE as a practical and cost‑effective way of assessing exposure

This is exactly what HSE inspectors are now asking businesses to demonstrate during visits.

Increased demand – and what that means for results times

Because of the current HSE inspection focus, demand for isocyanate testing has increased significantly across the UK.

At present, the Health and Safety Laboratory (HSL), which processes a large proportion of these samples, is experiencing testing delays of around two months due to volume, not quality or compliance issues.

This is important to be aware of:

• The delay is industry‑wide and reflects increased demand

• It does not affect the validity of the testing

• Results are still processed and reported in order

The practical takeaway is simple: starting the testing process sooner helps avoid unnecessary waiting later.

What employers can do now

If your workers may be exposed to isocyanates, sensible next steps include:

• Reviewing your COSHH risk assessment to ensure it reflects current working practices

• Checking that health surveillance and biological monitoring are in place where required

• Planning testing early, particularly if you are in a sector currently being inspected

• Making sure employees understand why testing is being done and how it protects them

Proactive action can help demonstrate compliance, protect worker health, and reduce stress if an inspection does take place.

Local support for employers in Kent, London, Sussex and Essex

We’re currently supporting a growing number of businesses across Kent, London, Sussex and Essex with isocyanate‑related occupational health advice and health surveillance.

If you’d like to discuss isocyanate testing, health surveillance, or wider occupational health support in a calm, practical way, you’re welcome to get in touch with our team.

Early advice and planning can make the process much smoother – for employers and employees alike.