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, among other things, some sealants, adhesives, PUR foam and surface coatings, and the substance can cause serious and chronic airway damage when inhaled. The Danish Working Environment Authority tightened the training requirement for work with isocyanate products in 2023: since 15 April 2023 both the person doing the work and the person supervising it must hold the training certificate (AMU 47942, 2 days), and since 24 August 2023 work with increased risk – e.g. spraying outside a booth or open handling above 45 °C – also requires a supplementary 1-day course (AMU 21204). The training must be renewed at least every 5 years, and if you have isocyanate training from before 15 April 2023, it must be renewed by 24 August 2028 at the latest.

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 safety data sheet and the workplace's instructions before you start using 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 the right precautions, spills or splashes can happen. If a chemical product gets into your eyes or onto your skin, rinse thoroughly with plenty of water immediately – section 4 on first aid in the safety data sheet tells you for how long and with what. If you suspect inhalation of vapours or dust from e.g. isocyanates or asbestos, get fresh air immediately and contact a doctor if the symptoms do not quickly subside. The faster you react, the lower the risk of permanent damage – which is why it is important to know the first aid for the particular substances you work with before an 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.”