Hazardous substances

The purpose of this article is to provide you with insight into cases where bricks may be contaminated and therefore cannot be reused.

Disclaimer: This is not a comprehensive guide on how to perform the renovation or demolition of structures containing hazardous substances, but an introduction to some of the key considerations one should be aware of.

Teacher's guide:

10. Brick_EN.pdf

Hazardous substances and protective gear

Reusing reduces the impact on the environment. However, there are cases where embedded materials may have been contaminated by hazardous substances and therefore cannot be reused. Additionally, you should be aware that, during the processing or demolition of building materials, it may be necessary for you to protect yourself with protective equipment.

Chimney

Materials in a chimney are typically neither reusable nor recyclable, as the brick has become contaminated with soot and heavy metals from smoke and combustion. Therefore, it is crucial to have a detailed plan for how the materials are broken down and handled before the work begins. It is essential that the executing craftsman wears protective equipment to ensure that the hazardous material does not harm them.

If there is doubt about whether the waste is contaminated, samples can be taken. These samples can document the presence of hazardous substances, allowing the appropriate safety measures to be taken. The samples can also specify the type of waste generated and thus determine where the waste should be deposited.

Duration: 60 minutes

Preparation: 10 minutes

Task and Reading: 50 minutes

En skorsten af mursten der er dækket af sod.
En murstensmur med et vindue.

Reveals on windows with elastic seals

In recent years, elastic seals have been used between masonry reveals and window and door sections. At times, the sealant material has contained various hazardous substances. Some of these hazardous substances have the ability to diffuse (spread) into adjacent structural components, leading to examples of bricks contaminated with hazardous substances.

To limit the spread of hazardous substances, these bricks should not be reused or recycled.

It can be investigated whether hazardous substances have diffused from the elastic seals into the masonry by taking a sample.

Glazed roof tiles

The glaze on glazed roof tiles contains heavy metals, including lead. It is still legal to use glazed roof tiles in new constructions, although, in almost all cases, they are deposited after removal. Before the removal of glazed roof tiles, a plan is made to ensure that the workers are not exposed to unnecessary health risks. The removal of roof tiles should be carried out in a manner that minimizes dust, as the dust may contain heavy metals that can be inhaled.

Surfaces on brick constructions

Many brick constructions have surface treatments. Some of these surface treatments contain hazardous substances. Before the demolition and renovation of brick constructions that have been surface-treated, it should be investigated whether the surface treatment contains hazardous substances. These samples are taken by specially trained personnel who should collect and analyze the samples before the demolition work begins.

Tile adhesive

In tile adhesive, various minerals that have later been found to be harmful to health have been used in the past. Typically, there is no cause for concern as long as the tile and adhesive are intact. During demolition, dust containing the hazardous minerals will typically be generated in most cases.

This is particularly true for asbestos, which was banned in the 1980s, but other hazardous substances may also be present in old tile adhesives.

General precautions

It is the employer's responsibility to protect employees from health hazards while work is being performed. Therefore, the employer must create a plan and provide detailed instructions to the workers before work involving hazardous substances begins. If in doubt, ask questions and seek more information in industry guidelines from the governing body.

Et sort tegltag der skinner i solen.

Task (50 minutes)

In this task, you, as a group, should focus on a demolition or renovation project that you or a group member have participated in or are familiar with. You need to determine whether there could potentially have been hazardous substances in the materials that were demolished. Remember to write down all your answers.

Start by reading the text if you haven't already. Then, provide a brief description of the project (15 minutes):

  1. What works were carried out?
  2. In which year was the house or building originally constructed?
  3. Has the house or building been renovated since? If yes, approximately when? (if unknown, then estimate)

Considerations (20 minutes):

  1. What hazardous substances could have been in the demolished materials during the work? Feel free to search the internet to solve the task. 

    • To help you find out which hazardous substances may be present in different types of constructions, you can use the overview below. The overview shows which hazardous substances could potentially be in constructions from specific time periods.

  2. How did you ensure protection against the hazardous substances?

  3. How should you have ensured protection against the hazardous substances?

Share your answers with the class (15 minutes):