Safe work with dyestuffs epoxy and isocyanates
The chemistry behind thermoset plastic and composite demands respect — how to protect yourself in practice
Plastic is not just a solid, finished material — during production you often work with reactive chemicals that only become the hardened plastic you know. Styrene in polyester resin as well as epoxy and isocyanates in adhesives, varnishes and certain resin types are substances that require you to know and follow the rules for safe work. The Work Authority has published specific guidelines on these substance groups because they are so widespread in industry.
§Styrene in fiberglass plastic
Styrene is the solvent that makes unsaturated polyester resin liquid before it hardens. The substance evaporates easily and can both be inhaled and absorbed through the skin. According to a review in Ugeskriftet.dk, the average styrene exposure level in the Danish fiberglass plastic industry has fallen significantly over decades — from around 100 ppm in the 1960s to around 10 ppm in the 1990s — with better ventilation, more closed processes and the spread of so-called LSE polyester (Low Styrene Emission), which releases less styrene during processing.
- 01Use spot extraction close to the laminating or spray point, not just general room ventilation.
- 02Prefer closed processes like vacuum infusion where possible — it significantly reduces evaporation.
- 03Use the personal protective equipment specified in the safety data sheet — typically gloves and eye protection, and respiratory protection at high concentration or poor ventilation.
- 04Change work clothes that have been wetted with resin, so skin contact doesn't continue the rest of the day.
§Epoxy and isocyanates
Epoxy adhesive
§Safety data sheets and workplace instruction
Every chemical product you work with must have a Safety Data Sheet from the supplier. Section 8 of the SDS provides, among other things, limit values and requirements for personal protective equipment. At each workplace, the SDS is translated into a workplace use instruction (APB), which is the practical guidance on how your specific product is handled safely at your workplace — including first aid if an accident occurs.
| Assignment | Typical personal protective equipment | Why |
|---|---|---|
| Hand lamination with polyester/styrene | Nitrile gloves, eye protection, point extraction | Styrene is absorbed through skin and inhalation |
| Work with epoxy adhesive or resin | Chemical-resistant gloves, long-sleeved clothing | Risk of contact eczema and sensitization |
| Spraying with isocyanate-containing varnish | Supplied air respiratory protection, full-face mask | Isocyanates can trigger asthma if inhaled |
If the accident happens
If resin, glue or lacquer comes into contact with skin or eyes, the area must be rinsed immediately with plenty of water, and a doctor should be sought if irritation persists. The workplace instruction manual must always describe the specific first aid procedure for the exact product you are working with — general advice does not replace local instructions.
“What you can't see or smell clearly is often what damages most in the long run.”
— Basic principle in chemical working environment