Inorganic particulates are among the most common airborne hazards encountered in occupational and indoor environments. They include mineral dusts, acid mists, salts, fibres, and general particulate matter generated during manufacturing, construction, maintenance, and material handling processes.
For EHS consultants, accurate assessment of inorganic particulates requires more than measuring “total dust.” The chemical identity of the material, its solubility, and its particle size fraction (inhalable vs. respirable) directly influence toxicological relevance and regulatory interpretation. Selecting the correct sampling strategy and analytical method is essential for defensible exposure assessments.
Below is a structured overview of laboratory tests commonly used to evaluate inorganic particulates, excluding metals.
Non-Volatile Acids
Acid mists and droplets may be generated in battery operations, chemical processing, fertilizer production, and surface treatment processes. Even when classified as non-volatile, these substances can form airborne aerosols under certain conditions.
Typical analytes include:
- Sulfuric acid
- Phosphoric acid
Sampling and analysis support comparison with occupational exposure limits and evaluation of engineering controls.
Inorganic Salts
Airborne salts may be produced during mixing, drying, grinding, or packaging operations. Their health impact depends on solubility and chemical composition.
Commonly assessed compounds include:
- Soluble fluorides
- Soluble cyanides
Laboratory results help determine inhalation exposure and support compliance assessments.
Metals Oxides and Mineral Dusts
Mineral-based dusts are widely encountered in construction, mining, ceramics, cement production, and material processing. In many cases, particle size fraction is critical for regulatory comparison.
Examples include:
- Welding fumes
- Crystalline silica
- Talc
- Cement dust
Respirable crystalline silica, in particular, requires precise sampling and analytical techniques due to its well-established health risks and stringent exposure limits.
Fibres
Inorganic fibrous materials require specialized collection and microscopy-based identification. Fibre morphology, size distribution, and counting rules depend on the regulatory framework and project scope.
Relevant categories include:
- Asbestos fibres
- Refractory ceramic fibres
- Glass fibres (reported as fibres or total dust where applicable)
Proper method selection is essential to ensure that results are legally and technically defensible.
Particulates Not Otherwise Regulated (PNOR)
When substance-specific exposure limits do not apply, general dust categories may be used:
Size-selective sampling is fundamental, as inhalable and respirable fractions represent different deposition regions within the respiratory system.
Laboratory Support
LCS Laboratory Inc. provides laboratory analysis and air sampling equipment rental to support occupational exposure assessments and indoor air quality investigations. A complete list of available tests is provided on the price list page. For project-specific questions or to arrange laboratory services, consultants are encouraged to contact our laboratory directly. ©
