Work with epoxy and isocyanates

Epoxy and isocyanates (including polyurethane, PUR) are reactive chemical products used for adhesives, sealants, floor coatings, paints, casting and foam. They have strong properties but are also among the substances that can cause the most widespread work-related allergies and respiratory diseases. Therefore the work is subject to requirements for special training.

You may only work professionally with epoxy and isocyanates if you have completed the mandatory training. The training ensures that you know the hazards of the substances, know how the work is planned and carried out safely, and can use the protective equipment correctly. The requirement is in § 16 and Annex 10 of the Executive Order on occupational health and safety training (BEK no. 1978/2021) and in Annex 2, item 7 of the Executive Order on work with substances and materials (BEK no. 581/2026).

The rules in Annex 2 apply to these substances and materials:

• 01Epoxy with an average molecular weight of 700 or less, and materials containing 1 percent by weight or more of it.
• 02Reactive solvents with epoxy groups, and materials containing 0.2 percent by weight or more of them.
• 03Monomeric diisocyanates, and materials with 0.1 percent by weight or more of them.
• 04Materials with 0.5 percent by weight of prepolymers or more.

Percent by weight is how large a share of the product's weight the substance makes up. 1 percent by weight is 1 gram per 100 grams of product.

Anyone who carries out epoxy work must have the training. For isocyanates, the requirement applies both to the person who carries out the work and to the person who supervises it. The requirement does not apply to the manufacture of the substances themselves.

• 01Skin contact can cause eczema and allergic contact allergy
• 02Inhalation of fumes spray mist or dust can cause airway irritation and asthma
• 03Isocyanates can trigger airway hypersensitivity even at low concentrations
• 04Splashes in the eyes can cause serious irritation

Work is planned so skin and inhalation contact is avoided. This means shielding, good ventilation or process extraction and working as closed as possible. Hands are protected with suitable gloves and you avoid touching your face, phone and handles with contaminated gloves. Spillage is wiped up immediately and contaminated material is disposed of as hazardous waste.

The products must be applied with a filler knife, brush, roller or caulking gun. Spraying is only allowed in closed systems, spray booths and spray enclosures — and in some special exceptions: ships, offshore, bridges, tanks, sports floors and outdoor courts.

Under the exceptions, spraying is allowed for at most 2 periods of 2 hours per day. If conditions are optimal, up to 5 hours. In spaces with very difficult access the limit is 2 × 1 hour, and in strenuous working postures 3 × 1 hour. The exceptions must be notified in writing to the Danish Working Environment Authority (Arbejdstilsynet) at least 14 days in advance.

• 01A washbasin with running, lukewarm water. The taps must not be hand-operated.
• 02Shower rooms.
• 03Separate changing rooms where street clothes and work clothes are kept apart.
• 04No food, drink or smoking at the workplace.
• 05Spills and used towels go in labelled containers.
• 06An eyewash bottle within reach.

Protective equipment is chosen according to the product safety data sheet: chemical-resistant gloves of the right type, safety glasses or visor, protective suit and — with vapours or spraying — suitable respiratory protection with the correct filter. The protective equipment must match the specific product being used; wrong glove material can be penetrated.

Each product has a Safety Data Sheet that describes hazards, personal protective equipment, first aid and disposal. It is read before work. The package's hazard labelling and H- and P-statements tell you what to watch out for. In case of skin contact or splash in the eyes, follow the first aid instructions immediately.

The air may contain at most this much diisocyanate:

NCO means that the value is measured as the isocyanate groups attached to the substance. The diisocyanates have the note H. It means that the substance can be absorbed through the skin.

If you get eczema, breathing difficulties, chemical burns or eye injuries, you must see a doctor.