What are Isocyanates?
Isocyanates are a group of highly reactive chemicals commonly found in 2-pack paints, coatings and polyurethane products used in automotive refinishing, joinery, furniture production, metal fabrication and more. These chemicals help paint harden and achieve a durable finish, but they can easily become airborne as vapour, mist or fine droplets during spraying and sanding.
Why Are They Dangerous?
What makes isocyanates especially hazardous is that they are often odourless and colourless — meaning you may not realise you’re exposed until symptoms start.
Even low-level exposure can cause serious health effects:
Respiratory Sensitisation & Occupational Asthma
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Inhalation of isocyanate vapours or mist can irritate the lungs and airways.
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With repeated exposure, workers can develop isocyanate-induced asthma — a form of occupational asthma that can be permanent.
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Once sensitised, even tiny amounts of isocyanates can trigger serious breathing difficulties.
Other Health Risks
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Skin and mucous membrane irritation (eyes, nose, throat).
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Dermatitis & chronic skin sensitisation from contact.
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Symptoms like coughing, wheezing, chest tightness, breathlessness and irritation may occur during or after work.
According to occupational health studies and WHS guides, isocyanates are among the most common causes of occupational asthma worldwide, particularly in spray-painting environments.
Why Standard Gas Filters Aren’t Enough
Many workers rely on disposable gas masks or standard respirators. However:
For isocyanates, Safe Work Australia and Worksafe guidelines state that supplied-air respiratory protection (e.g., airline respirators) is required when spraying these materials. Organic vapour cartridges or powered air-purifying respirators (PAPRs) do not provide adequate protection against isocyanate vapours and aerosols.
That means the common respirator many workers wear isn’t enough — especially in high-exposure tasks like spray painting or sanding unfinished surfaces.
Which Jobs Are Most At Risk?
Workers commonly exposed include:
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Automotive panel beaters, refinishers, body shops and painters
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Construction spray-coaters and joinery finishing crews
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Industrial coating operators and woodworkers
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Furniture and cabinet makers using polyurethane paints and coatings
Protecting Your Team
Good workplace controls should include:
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Proper ventilation and spray booths
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Supplied-air respirators (not just cartridge-style masks)
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Full protective clothing and eye protection
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Training on handling hazardous chemicals
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Health monitoring for workers at risk
What Does a Supplied-Air System Actually Look Like?
A typical supplied-air respirator system used for spraying 2-pack paints consists of:
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A full-face mask or hood (such as a visor-style mask)
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A belt-mounted regulator with dual outlets, allowing both the spray gun and the respirator to run from the same compressed air supply, meaning no duplicated hoses or second compressor are required
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An airline hose
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A dedicated clean air source, usually a workshop air compressor fitted with the correct filtration
Instead of filtering contaminated air, a supplied-air system delivers clean, breathable air directly to the user, completely isolating them from isocyanate vapours and spray mist. This is why supplied air is recommended — and in many cases required — when working with isocyanate-containing products.
Systems like the CleanAIR UniMask supplied-air kits are designed specifically for these environments, providing a continuous flow of fresh air while maintaining visibility, comfort, and compliance during extended spray work.
Important: Standard disposable masks, reusable cartridge respirators and even PAPR systems rely on filtering the surrounding air. When it comes to isocyanates, filtering is not enough — a supplied-air system is the correct control.
👉 View our supplied-air respirator range here or get in touch with our team to make sure your setup is right for your application.
The Bottom Line
Isocyanates are a serious health hazard — especially because workers can be sensitised without obvious warning signs, and once sensitised, even small exposures can be dangerous. Understanding these risks and using the right protective equipment isn’t just compliance — it’s protecting lives.
Find Out More
If you work with 2-pack paints, coatings or polyurethane products and want help assessing risk or supplying the correct supplied-air respiratory protection systems for your team, get in touch — we can help you keep your people safe and compliant.