Color is the first thing the eye sees — and the last thing the customer remembers.

Concrete layer and brick layer is largely about earth, concrete and stone, but some of the materials you encounter along the way are chemically dangerous if handled incorrectly. Isocyanate-containing products, epoxy, cold asphalt and bitumen as well as asbestos in older buildings all require special knowledge and in several cases documented training before you are allowed to work with them.

Isocyanates are found in certain grouts, adhesives, PUR foam and surface treatments, among other things, and the substance can cause serious and chronic airway damage if inhaled. The Danish Working Environment Authority tightened the training requirement for work with isocyanate-containing products from August 24, 2023: both the person performing the work and the person training or supervising it must have completed an approved course – typically a one-day course developed by Industry's Joint Committee under AMU. If you already have isocyanate training from before 2023, it must be renewed by 2028.

Epoxy products and bitumen-containing materials such as cold asphalt are used among other things for damp-proofing, bonding and repair work. They can cause allergic reactions and eczema on skin contact, and some of them give off vapours that must be kept away from breathing. The education's competence objectives therefore require that you can take ergonomic and safety measures, including choosing and using personal protective equipment, and that you can carry out work with cold asphalt, bitumen, epoxy and isocyanate products in accordance with Arbejdstilsynet (Danish Working Environment Authority) regulations and education requirements.

In older buildings and systems, you may encounter asbestos-containing materials, which were common until the ban in the 1980s. Asbestos fibres are carcinogenic when inhaled, and the rule is therefore simple: you must be able to recognise the risk and know when work requires substitution — that is, a dangerous material is replaced by a safe alternative — based on a concrete risk assessment. Actual demolition or removal of asbestos requires special authorisation and training beyond ordinary carpentry.

• 01Read the workplace instruction manual (APV), before you start with a new product
• 02Choose the right respiratory protection, gloves and protective suit for the task
• 03Avoid skin contact with epoxy and bitumen—wash immediately if spilled.
• 04Ensure ventilation or extraction when working in enclosed spaces
• 05Use substitution where a hazardous substance can be replaced by a less hazardous one

Even with proper precautions spills or splashes can occur. If a chemical product gets in your eyes or on your skin rinse immediately with plenty of water — the workplace instructions tell you how long and with what. If you suspect inhalation of fumes or dust from eg isocyanates or asbestos get fresh air immediately and contact a doctor if symptoms do not quickly subside. The faster you react the less risk of permanent damage — that is why it is important to know first aid for exactly the substances you work with before the accident happens.

It may sound like a minor thing alongside soil and concrete, but chemical safety is just as much a part of the trade as bracing an excavation. The better you know the substances, the safer you can work with them — without it costing you a whole career.

The rules are continuously tightened as new knowledge about the harmful effects of substances emerges, and it is therefore an area where you as a professional must keep yourself updated throughout your working life – not just remember what you learned in basic training.

“The most dangerous chemistry on a construction site is often the one you don't notice — because you don't know you're working with it.”