Analysing asbestos in road materials
Do you need to check for asbestos in a road surface, asphalt mix or recycled asphalt aggregate? Lab’Eau-Air-Sol analyses road materials from resurfacing, milling, demolition and material recovery projects.
What is asbestos?
Asbestos is a group of naturally occurring minerals with a fibrous structure. It can occur in road materials because it was added to a mix or because asbestos minerals occur naturally in some aggregates.
Asbestos in asphalt mixes
Some older asphalt mixes in Quebec may contain asbestos. Chrysotile was added to certain mixes in the past. Asbestos fibres, including actinolite or tremolite, may also be associated with natural aggregates used to manufacture asphalt mixes.
Recycled asphalt aggregates
Aggregates recovered through road milling or resurfacing may contain asbestos from older asphalt mixes or from aggregates used in those mixes.
What the analysis involves
An asphalt or granular material sample is examined in the laboratory to look for asbestos. Asphalt is a complex matrix: asbestos may be present in the bituminous binder or associated with the aggregate fraction. Characterization must take this particular matrix into account.
Materials that can be analysed
Depending on the assignment, the laboratory can analyse:
- Asphalt mixes.
- Materials recovered through road milling.
- Recycled asphalt aggregates.
- Aggregates used in road structures.
- Granular materials associated with roadwork.
Preparation suited to bituminous materials
The bituminous matrix can make analysis more complex than conventional building materials. The potentially low asbestos concentration and the properties of bitumen must be considered when preparing a sample.
Lab’Eau-Air-Sol has developed a preparation approach suited to bituminous samples to help detect low asbestos concentrations. The analysis and preparation required may vary with the sample and project objectives.
When to request this analysis
- Before roadwork requiring characterization of an asphalt mix.
- To check for asbestos in recycled asphalt aggregates.
- Before milling, resurfacing or pavement demolition.
- Before reusing or recovering road materials.
- To document the presence or absence of asbestos in road materials before a project.
Checking for asbestos can be important before handling, reusing, recovering or disposing of road materials, including disposal at an engineered landfill. Analysis provides data on the submitted sample to support project professionals’ decisions.
This analysis can serve contractors, municipalities, consulting engineering firms and infrastructure managers who need to characterize road materials.
Before sending your samples
If you are unsure about the type or quantity of material to collect, contact our team before sampling. Consult the sampling instructions and include the appropriate request form with your samples.